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121.
Aliza K. De Nobrega Eric J. Noakes Natalie A. Storch Alana P. Mellers Lisa C. Lyons 《International journal of molecular sciences》2022,23(20)
Alcohol abuse is a significant public health problem. While considerable research has shown that alcohol use affects sleep, little is known about the role of sleep deprivation in alcohol toxicity. We investigated sleep as a factor modulating alcohol toxicity using Drosophila melanogaster, a model for studies of sleep, alcohol, and aging. Following 24 h of sleep deprivation using a paradigm that similarly affects males and females and induces rebound sleep, flies were given binge-like alcohol exposures. Sleep deprivation increased mortality, with no sex-dependent differences. Sleep deprivation also abolished functional tolerance measured at 24 h after the initial alcohol exposure, although there was no effect on alcohol absorbance or clearance. We investigated the effect of chronic sleep deprivation using mutants with decreased sleep, insomniac and insulin-like peptide 2, finding increased alcohol mortality. Furthermore, we investigated whether pharmacologically inducing sleep prior to alcohol exposure using the GABAA-receptor agonist 4,5,6,7-tetrahydroisoxazolo(5,4-c)pyridin-3-ol (THIP) mitigated the effects of alcohol toxicity on middle-aged flies, flies with environmentally disrupted circadian clocks, and flies with short sleep. Pharmacologically increasing sleep prior to alcohol exposure decreased alcohol-induced mortality. Thus, sleep prior to binge-like alcohol exposure affects alcohol-induced mortality, even in vulnerable groups such as aging flies and those with circadian dysfunction. 相似文献
122.
Anne-Louise Gannon Annalucia L. Darbey Grace Chensee Ben M. Lawrence Liza ODonnell Joanna Kelso Natalie Reed Shanmathi Parameswaran Sarah Smith Lee B. Smith Diane Rebourcet 《International journal of molecular sciences》2022,23(23)
Glucocorticoids are steroids involved in key physiological processes such as development, metabolism, inflammatory and stress responses and are mostly used exogenously as medications to treat various inflammation-based conditions. They act via the glucocorticoid receptor (GR) expressed in most cells. Exogenous glucocorticoids can negatively impact the function of the Leydig cells in the testis, leading to decreased androgen production. However, endogenous glucocorticoids are produced by the adrenal and within the testis, but whether their action on GR in Leydig cells regulates steroidogenesis is unknown. This study aimed to define the role of endogenous GR signalling in adult Leydig cells. We developed and compared two models; an inducible Cre transgene driven by expression of the Cyp17a1 steroidogenic gene (Cyp17-iCre) that depletes GR during development and a viral vector-driven Cre (AAV9-Cre) to deplete GR in adulthood. The delivery of AAV9-Cre ablated GR in adult mouse Leydig cells depleted Leydig cell GR more efficiently than the Cyp17-iCre model. Importantly, adult depletion of GR in Leydig cells caused reduced expression of luteinising hormone receptor (Lhcgr) and of steroidogenic enzymes required for normal androgen production. These findings reveal that Leydig cell GR signalling plays a physiological role in the testis and highlight that a normal balance of glucocorticoid activity in the testis is important for steroidogenesis. 相似文献
123.
Natasha de Alwis Bianca R. Fato Sally Beard Natalie K. Binder Tuuhevaha J. Kaituu-Lino Kenji Onda Natalie J. Hannan 《International journal of molecular sciences》2022,23(17)
Previously, we demonstrated that the proton pump inhibitor, esomeprazole magnesium hydrate (MH), could have potential as a repurposed treatment against preeclampsia, a serious obstetric condition. In this study we investigate the difference in the preclinical effectiveness between 100 µM of esomeprazole MH and its hydration isomer, esomeprazole magnesium trihydrate (MTH). Here, we found that both treatments reduced secretion of sFLT-1 (anti-angiogenic factor) from primary cytotrophoblast, but only esomeprazole MH reduced sFLT-1 secretion from primary human umbilical vein endothelial cells (assessed via ELISA). Both drugs could mitigate expression of the endothelial dysfunction markers, vascular cell adhesion molecule-1 and endothelin-1 (via qPCR). Neither esomeprazole MH nor MTH quenched cytotrophoblast reactive oxygen species production in response to sodium azide (ROS assay). Finally, using wire myography, we demonstrated that both compounds were able to induce vasodilation of human omental arteries at 100 µM. Esomeprazole is safe to use in pregnancy and a candidate treatment for preeclampsia. Using primary human tissues and cells, we validated that esomeprazole is effective in enhancing vascular relaxation, and can reduce key factors associated with preeclampsia, including sFLT-1 and endothelial dysfunction. However, esomeprazole MH was more efficacious than esomeprazole MTH in our in vitro studies. 相似文献
124.
Mohammed H. Abuwarwar Alfie T. Baker Jeffrey Harding Natalie L. Payne Andras Nagy Konstantin Knoblich Anne L. Fletcher 《International journal of molecular sciences》2021,22(4)
T cell immunotherapy is now a mainstay therapy for several blood-borne cancers as well as metastatic melanoma. Unfortunately, many epithelial tumors respond poorly to immunotherapy, and the reasons for this are not well understood. Cancer-associated fibroblasts (CAFs) are the most frequent non-neoplastic cell type in most solid tumors, and they are emerging as a key player in immunotherapy resistance. A range of immortalized CAF lines will be essential tools that will allow us to understand immune responses against cancer and develop novel strategies for cancer immunotherapy. To study the effect of CAFs on T cell proliferation, we created and characterized a number of novel immortalized human CAFs lines (Im-CAFs) from human breast, colon, and pancreatic carcinomas. Im-CAFs shared similar phenotypes, matrix remodeling and contraction capabilities, and growth and migration rates compared to the primary CAFs. Using primary isolates from breast carcinoma, colorectal carcinoma, and pancreatic ductal adenocarcinoma, we report that CAFs across major tumor types are able to potently suppress T cell proliferation in vitro. Im-CAFs retained this property. Im-CAFs are a key tool that will provide important insights into the mechanisms of CAF-mediated T cell suppression through techniques such as CRISPR-Cas9 modification, molecular screens, and pipeline drug testing. 相似文献
125.
Kruse Natalie Hawkins Caleb López Dina L. Johnson Kelly 《Mine Water and the Environment》2019,38(4):718-734
Mine Water and the Environment - The East Branch of Raccoon Creek, Ohio is highly impacted by pre-regulation coal mining and contains 10 steel slag leach beds that passively treat the low pH, and... 相似文献
126.
Jeffrey R. Henig Thomas T. Holyoke Natalie Lacireno‐Paquet Michele Moser 《Journal of Urban Affairs》2003,25(1):37-54
Abstract In this article we re‐examine the dualist theory of public and private sector providers of public services. While this theory holds that private sector providers exhibit a behavior substantively different from those of the public sector, i.e., they respond to external pressures with market‐oriented behavior instead of political behavior, we argue that these actors actually can and often do respond in a political manner. Furthermore, we argue that a political response is as likely to be exhibited by for‐profit providers, who should be the most free‐market oriented, as nonprofit organizations. We provide evidence for our proposition drawn from our study of the behavior of charter schools, market‐based providers of public education, and charter school advocates in the District of Columbia and find that when faced with numerous challenges, charters responded by lobbying government for assistance instead of competing in the market place. We conclude that the line of demarcation between the behavior of public and private sector providers is actually quite blurred and when faced with similar problems in the delivery of public services, both forms of providers will respond in a similar manner. 相似文献
127.
Investigated how 58 managers from 9 organizations describe productivity, productivity improvement, and office automation's potential contribution. Ss used a wide range of terms to describe organizational and departmental productivity. Answers to questions on productivity improvement bore little resemblance to answers on definitions of productivity. Results are discussed in terms of the distinction Ss made between the process of productivity improvement (means) and the productivity evaluation criteria (ends). Questions are raised about the apparent lack of congruence between productivity definitions and productivity improvement and about how Ss enacted the relationship between the evaluation criteria of productivity and productivity improvement. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
128.
Compton Donald L.; Olinghouse Natalie G.; Elleman Amy; Vining Jan; Appleton Amanda C.; Vail Jennifer; Summers Marci 《Canadian Metallurgical Quarterly》2005,97(1):55
The authors explored a new means of assessing responsiveness to decoding-skill intervention to model individual differences in the transfer of decoding-skill gains to other aspects of reading acquisition in 35 children, Grades 3 through 5, with reading disabilities. Seven different parameters, representing responsiveness to decoding instruction, were estimated for each child and used to predict gains on standardized reading tests assessing word attack, word identification, and text reading accuracy, fluency, and comprehension. Results indicated that several estimates of an individual's responsiveness to instruction were related to gains in other aspects of reading. Results also suggested that the most appropriate unit of analysis for examining transfer is the individual, not the group. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
129.
Fastenau Philip S.; Denburg Natalie L.; Abeles Norman 《Canadian Metallurgical Quarterly》1996,11(1):140
Age differences in processing resources seem salient to age-related declines in secondary (or "recent") memory. Community-dwelling adults (N?=?90, ages 30–80) completed 4 memory tests: Wechsler Memory Scale—Revised (WMS-R), Logical Memory (LM), Cowboy Story (CS), WMS-R Visual Reproductions (VR), and Extended Complex Figure Test (ECFT; Fastenau, in press). Two space-capacity measures (WMS-R Digit Span and Visual Memory Span) and 4 processing speed measures (cancellation and mental-tracking tasks) assessed processing resources. A statistical control procedure was used to isolate retrieval efficiency and measure contributions of age and processing resources to retrieval. A negative relationship between age and retrieval efficiency emerged on all measures (p? 相似文献
130.
Natalie Boehnke Jacquelin K. Kammeyer Robert Damoiseaux Heather D. Maynard 《Advanced functional materials》2018,28(10)
Glucagon is a peptide hormone used for the treatment of hypoglycemia; however, its clinical potential is limited by its insolubility and instability in solution. Herein, the encapsulation, stabilization, and release of glucagon by trehalose glycopolymer nanogels are reported. Methacrylate‐functionalized trehalose is copolymerized with pyridyl disulfide ethyl methacrylate using free radical polymerization conditions to form trehalose glycopolymers with thiol‐reactive handles. Glucagon is chemically modified to contain two thiol groups and is subsequently utilized as the cross‐linker to form redox‐responsive trehalose nanogels with greater than 80% conjugation yield. Nanogel formation and subsequent glucagon stabilization are characterized using polyacrylamide gel electrophoresis, dynamic light scattering, and transmission electron microscopy. It is determined that the solution stability of the glucagon increased from less than 24 h to at least three weeks in the nanogel form. Additionally, in vitro activity of the synthesized glucagon analog and released glucagon is investigated, demonstrating that the glucagon remains active after modification. It is anticipated that these glucagon–nanogel conjugates will be useful as a stabilizing glucagon formulation, allowing for cargo release under mild reducing conditions. 相似文献