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991.
992.
Guinever E. Imperio Mohsen Javam Phetcharawan Lye Andrea Constantinof Caroline E. Dunk Fernando M. Reis Stephen J. Lye William Gibb Stephen G. Matthews Tania Maria Ortiga‐Carvalho Enrrico Bloise 《Journal of cellular and molecular medicine》2019,23(1):610-618
The ATP‐binding cassette (ABC) transporters control placental transfer of several nutrients, steroids, immunological factors, chemicals, and drugs at the maternal‐fetal interface. We and others have demonstrated a gestational age‐dependent expression pattern of two ABC transporters, P‐glycoprotein and breast cancer resistance protein throughout pregnancy. However, no reports have comprehensively elucidated the expression pattern of all 50 ABC proteins, comparing first trimester and term human placentae. We hypothesized that placental ABC transporters are expressed in a gestational‐age dependent manner in normal human pregnancy. Using the TaqMan® Human ABC Transporter Array, we assessed the mRNA expression of all 50 ABC transporters in first (first trimester, n = 8) and third trimester (term, n = 12) human placentae and validated the resulting expression of selected ABC transporters using qPCR, Western blot and immunohistochemistry. A distinct gene expression profile of 30 ABC transporters was observed comparing first trimester vs. term placentae. Using individual qPCR in selected genes, we validated the increased expression of ABCA1 (P < 0.01), ABCA6 (P < 0.001), ABCA9 (P < 0.001) and ABCC3 (P < 0.001), as well as the decreased expression of ABCB11 (P < 0.001) and ABCG4 (P < 0.01) with advancing gestation. One important lipid transporter, ABCA6, was selected to correlate protein abundance and characterize tissue localization. ABCA6 exhibited increased protein expression towards term and was predominantly localized to syncytiotrophoblast cells. In conclusion, expression patterns of placental ABC transporters change as a function of gestational age. These changes are likely fundamental to a healthy pregnancy given the critical role that these transporters play in the regulation of steroidogenesis, immunological responses, and placental barrier function and integrity. 相似文献
993.
Qingzhi An Qing Sun Andreas Weu David Becker‐Koch Fabian Paulus Sebastian Arndt Fabian Stuck A. Stephen K. Hashmi Nir Tessler Yana Vaynzof 《Liver Transplantation》2019,9(33)
Four π‐extended phosphoniumfluorene electrolytes (π‐PFEs) are introduced as hole‐blocking layers (HBL) in inverted architecture planar perovskite solar cells with the structure of ITO/PEDOT:PSS/MAPbI3/PCBM/HBL/Ag. The deep‐lying highest occupied molecular orbital energy level of the π‐PFEs effectively blocks holes, decreasing contact recombination. It is demonstrated that the incorporation of π‐PFEs introduces a dipole moment at the PCBM/Ag interface, resulting in significant enhancement of the built‐in potential of the device. This enhancement results in an increase in the open‐circuit voltage of the device by up to 120 mV, when compared to the commonly used bathocuproine HBL. The results are confirmed both experimentally and by numerical simulation. This work demonstrates that interfacial engineering of the transport layer/contact interface by small molecule electrolytes is a promising route to suppress nonradiative recombination in perovskite devices and compensates for a nonideal energetic alignment at the hole‐transport layer/perovskite interface. 相似文献
994.
Gangadharan Nishanthi Turner Richard Field Ray Oliver Stephen G. Slater Nigel Dikicioglu Duygu 《Bioprocess and biosystems engineering》2019,42(9):1399-1408
Bioprocess and Biosystems Engineering - There is a growing interest in mining and handling of big data, which has been rapidly accumulating in the repositories of bioprocess industries.... 相似文献
995.
Stephen A. Kelly Thomas S. Moody Brendan F. Gilmore 《Engineering in Life Science》2019,19(10):721-725
The increasing demand for freshwater and the continued depletion of available resources has led to a deepening global water crisis. Significant water consumption required by many biotechnological processes contributes to both the environmental and economic cost of this problem. Relatively few biocatalytic processes have been developed to utilize the more abundant supply of seawater, with seawater composition and salinity limiting its use with many mesophilic enzymes. We recently reported a salt tolerant ω‐transaminase enzyme, Ad2‐TAm, isolated from the genome of a halophilic bacterium, Halomonas sp. CSM‐2, from a Triassic period salt mine. In this study we aimed to demonstrate its applicability to biocatalytic reactions carried out in a seawater‐based medium. Ad2‐TAm was examined for its ability to aminate the industrially relevant substrate, furfural, in both seawater and freshwater‐based reaction systems. Furfural was aminated with 53.6% conversion in a buffered seawater system, displaying improved function versus freshwater. Ad2‐TAm outperformed the commonly employed commercial ω‐TAms from Chromobacterium violaceum and Vibrio fluvialis, both of which showed decreased conversion in seawater. Given the increasingly precarious availability of global freshwater, such applications of enzymes from halophiles have the ability to reduce demand for freshwater in large‐scale industrial processes, delivering considerable environmental and economic benefits. 相似文献
996.
Jun Zhang Kevin A. Fengler John L. Van Hemert Rajeev Gupta Nick Mongar Jindong Sun William B. Allen Yang Wang Benjamin Weers Hua Mo Renee Lafitte Zhenglin Hou Angela Bryant Farag Ibraheem Jennifer Arp Kankshita Swaminathan Stephen P. Moose Bailin Li Bo Shen 《Plant biotechnology journal》2019,17(12):2272-2285
997.
998.
Robyn F. Powell Anthony R. Magee Felix Forest Robyn S. Cowan J. Stephen Boatwright 《分类学与生物多样性》2019,17(2):110-123
The Bushmanland Inselberg Region (BIR) of South Africa provides an ideal system to study population interactions, as these inselbergs function as islands of Succulent Karoo surrounded by Nama Karoo vegetation. The population genetics of four Conophytum taxa endemic to the quartz-associated habitats of inselbergs in the BIR were investigated using amplified fragment length polymorphisms (AFLP), namely C. marginatum subsp. haramoepense, C. marginatum subsp. marginatum, C. maughanii, and C. ratum. Conophytum marginatum colonizes the quartz outcrops on the summits of the inselbergs, while C. maughanii and C. ratum occupy quartz patches at the summit and base of the inselbergs. A total of 24 populations were sampled to assess genetic differentiation between populations of each species, specifically between summit and base populations of C. ratum, eastern and western populations of C. maughanii and populations of the two subspecies of C. marginatum. Moderate levels of genetic differentiation were recovered between the summit and base populations of C. ratum, with an indication of some genetic connectivity between the populations. Slight differentiation between the eastern and western populations of C. maughanii was recovered, however, this was not reflected in the PCoA and STRUCTURE results. In C. marginatum, no significant genetic differentiation was recovered between populations of the subspecies. These results may reflect evidence of different dispersal mechanisms in the species, with the genetic connectivity between populations of C. ratum possibly indicating dispersal through hygrochastic capsules, while genetic connectivity between populations of C. maughanii and C. marginatum may, for the first time, suggest long-distance dispersal, i.e. anemochory. This study provides the first insights into population interactions across the BIR and highlights the importance of conservation in the region, particularly of the Gamsberg, in light of the recent mining activities. 相似文献
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