bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unexpectedly long half‐life of metformin elimination in cases of metformin accumulation
Authors: Kajbaf F. , Bennis Y. , Hurtel‐Lemaire A.‐S. , Andréjak M. , Lalau J.‐D. 
Published: September 2015

AbstractIntroductionIn a study of the oral administration of a single dose of metformin to healthy participants, the estimated half‐life (t½) for the elimination of the drug from erythrocytes was found to be 23.4 h (compared with 2.7 h for metformin in plasma). However, these pharmacokinetic indices have not been well defined in metformin accumulation.MethodsWe systematically reviewed all the data on plasma and erythrocyte metformin assays available in our centre. We then selected patients with a plasma metformin concentration ≥ 5 mg/l and in whom the metformin concentration had been remeasured once or more at least 5 days after admission.ResultsTwelve patients met the aforementioned criteria. All but one of these patients displayed generally severe lactic acidosis on admission (mean ± sd pH and lactate: 6.88 ± 0.35 and 14.8 ± 6.56 mmol/l, respectively) and 11 were treated with dialysis. The mean ± sd time interval between the first and last blood sample collections for metformin measurement was 8.3 ± 3.2 days (range 5–14 days). Five days after the first sample had been collected, metformin was still detectable in plasma and in erythrocytes in all patients. Metformin remained detectable for up to 13 days (both in plasma and in erythrocytes). The estimated mean terminal t½ for metformin in plasma and erythrocytes was 51.9 and 43.4 h, respectively.ConclusionsThe prolonged elimination of accumulated metformin (even after dialysis therapy) challenges the traditional view that the drug clears rapidly because of a short half‐life in plasma.
Plants mediate soil organic matter decomposition in response to sea level rise
Authors: Mueller Peter , Jensen Kai , Megonigal James Patrick 
Published: September 2015

AbstractTidal marshes have a large capacity for producing and storing organic matter, making their role in the global carbon budget disproportionate to land area. Most of the organic matter stored in these systems is in soils where it contributes 2–5 times more to surface accretion than an equal mass of minerals. Soil organic matter (SOM) sequestration is the primary process by which tidal marshes become perched high in the tidal frame, decreasing their vulnerability to accelerated relative sea level rise (RSLR). Plant growth responses to RSLR are well understood and represented in century‐scale forecast models of soil surface elevation change. We understand far less about the response of SOM decomposition to accelerated RSLR. Here we quantified the effects of flooding depth and duration on SOM decomposition by exposing planted and unplanted field‐based mesocosms to experimentally manipulated relative sea level over two consecutive growing seasons. SOM decomposition was quantified as CO2 efflux, with plant‐ and SOM‐derived CO2 separated via δ13CO2. Despite the dominant paradigm that decomposition rates are inversely related to flooding, SOM decomposition in the absence of plants was not sensitive to flooding depth and duration. The presence of plants had a dramatic effect on SOM decomposition, increasing SOM‐derived CO2 flux by up to 267% and 125% (in 2012 and 2013, respectively) compared to unplanted controls in the two growing seasons. Furthermore, plant stimulation of SOM decomposition was strongly and positively related to plant biomass and in particular aboveground biomass. We conclude that SOM decomposition rates are not directly driven by relative sea level and its effect on oxygen diffusion through soil, but indirectly by plant responses to relative sea level. If this result applies more generally to tidal wetlands, it has important implications for models of SOM accumulation and surface elevation change in response to accelerated RSLR.
Beyond just sea‐level rise: considering macroclimatic drivers within coastal wetland vulnerability assessments to climate change
Authors: Osland Michael J. , Enwright Nicholas M. , Day Richard H. , Gabler Christopher A. , Stagg Camille L. , Grace James B. 
Published: September 2015

AbstractDue to their position at the land‐sea interface, coastal wetlands are vulnerable to many aspects of climate change. However, climate change vulnerability assessments for coastal wetlands generally focus solely on sea‐level rise without considering the effects of other facets of climate change. Across the globe and in all ecosystems, macroclimatic drivers (e.g., temperature and rainfall regimes) greatly influence ecosystem structure and function. Macroclimatic drivers have been the focus of climate change‐related threat evaluations for terrestrial ecosystems, but largely ignored for coastal wetlands. In some coastal wetlands, changing macroclimatic conditions are expected to result in foundation plant species replacement, which would affect the supply of certain ecosystem goods and services and could affect ecosystem resilience. As examples, we highlight several ecological transition zones where small changes in macroclimatic conditions would result in comparatively large changes in coastal wetland ecosystem structure and function. Our intent in this communication is not to minimize the importance of sea‐level rise. Rather, our overarching aim is to illustrate the need to also consider macroclimatic drivers within vulnerability assessments for coastal wetlands.
Winter severity determines functional trait composition of phytoplankton in seasonally ice‐covered lakes
Authors: Özkundakci Deniz , Gsell Alena S. , Hintze Thomas , Täuscher Helgard , Adrian Rita 
Published: September 2015

AbstractHow climate change will affect the community dynamics and functionality of lake ecosystems during winter is still little understood. This is also true for phytoplankton in seasonally ice‐covered temperate lakes which are particularly vulnerable to the presence or absence of ice. We examined changes in pelagic phytoplankton winter community structure in a north temperate lake (Müggelsee, Germany), covering 18 winters between 1995 and 2013. We tested how phytoplankton taxa composition varied along a winter‐severity gradient and to what extent winter severity shaped the functional trait composition of overwintering phytoplankton communities using multivariate statistical analyses and a functional trait‐based approach. We hypothesized that overwintering phytoplankton communities are dominated by taxa with trait combinations corresponding to the prevailing winter water column conditions, using ice thickness measurements as a winter‐severity indicator. Winter severity had little effect on univariate diversity indicators (taxon richness and evenness), but a strong relationship was found between the phytoplankton community structure and winter severity when taxon trait identity was taken into account. Species responses to winter severity were mediated by the key functional traits: motility, nutritional mode, and the ability to form resting stages. Accordingly, one or the other of two functional groups dominated the phytoplankton biomass during mild winters (i.e., thin or no ice cover; phototrophic taxa) or severe winters (i.e., thick ice cover; exclusively motile taxa). Based on predicted milder winters for temperate regions and a reduction in ice‐cover durations, phytoplankton communities during winter can be expected to comprise taxa that have a relative advantage when the water column is well mixed (i.e., need not be motile) and light is less limiting (i.e., need not be mixotrophic). A potential implication of this result is that winter severity promotes different communities at the vernal equinox, which may have different nutritional quality for the next trophic level and ecosystem‐scale effects.
Algorithm of medication review in frail older people: Focus on minimizing the use of high‐risk medications
Authors: Poudel Arjun , Ballokova Anna , Hubbard Ruth E , Gray Leonard C , Mitchell Charles A , Nissen Lisa M , Scott Ian A 
Published: September 2015

AimFrail older people typically suffer several chronic diseases, receive multiple medications and are more likely to be institutionalized in residential aged care facilities. In such patients, optimizing prescribing and avoiding use of high‐risk medications might prevent adverse events. The present study aimed to develop a pragmatic, easily applied algorithm for medication review to help clinicians identify and discontinue potentially inappropriate high‐risk medications.MethodsThe literature was searched for robust evidence of the association of adverse effects related to potentially inappropriate medications in older patients to identify high‐risk medications. Prior research into the cessation of potentially inappropriate medications in older patients in different settings was synthesized into a four‐step algorithm for incorporation into clinical assessment protocols for patients, particularly those in residential aged care facilities.ResultsThe algorithm comprises several steps leading to individualized prescribing recommendations: (i) identify a high‐risk medication; (ii) ascertain the current indications for the medication and assess their validity; (iii) assess if the drug is providing ongoing symptomatic benefit; and (iv) consider withdrawing, altering or continuing medications. Decision support resources were developed to complement the algorithm in ensuring a systematic and patient‐centered approach to medication discontinuation. These include a comprehensive list of high‐risk medications and the reasons for inappropriateness, lists of alternative treatments, and suggested medication withdrawal protocols.ConclusionsThe algorithm captures a range of different clinical scenarios in relation to potentially inappropriate medications, and offers an evidence‐based approach to identifying and, if appropriate, discontinuing such medications. Studies are required to evaluate algorithm effects on prescribing decisions and patient outcomes. Geriatr Gerontol Int 2016; 16: 1002–1013.
Estimating Aquifer Properties Using Derivative Analysis of Water Level Time Series from Active Well Fields
Authors: Lewis Alan R. , Ronayne Michael J. , Sale Thomas C. 
Published: September 2015

AbstractWater level time series from groundwater production wells offer a transient dataset that can be used to estimate aquifer properties in areas with active groundwater development. This article describes a new parameter estimation method to infer aquifer properties from such datasets. Specifically, the method analyzes long‐term water level measurements from multiple, interacting groundwater production wells and relies on temporal water level derivatives to estimate the aquifer transmissivity and storativity. Analytically modeled derivatives are compared to derivatives calculated directly from the observed water level data; an optimization technique is used to identify best‐fitting transmissivity and storativity values that minimize the difference between modeled and observed derivatives. We demonstrate how the consideration of derivative (slope) behavior eliminates uncertainty associated with static water levels and well‐loss coefficients, enabling effective use of water level data from groundwater production wells. The method is applied to time‐series data collected over a period of 6 years from a municipal well field operating in the Denver Basin, Colorado (USA). The estimated aquifer properties are shown to be consistent with previously published values. The parameter estimation method is further tested using synthetic water level time series generated with a numerical model that incorporates the style of heterogeneity that occurs in the Denver Basin sandstone aquifers.
Comparative study of development parameters of four Ooencyrtus spp. (Hymenoptera: Encyrtidae) on natural and factitious hosts
Authors: Samra S. , Ghanim M. , Protasov A. , Mendel Z. 
Published: September 2015

AbstractBiological control approaches such as seeding and augmentation releases of populations of natural enemies mostly rely on the indoor production of predator or parasitoid species, often with the use of alternative prey/host species. In this study, we investigated several development parameters of four egg parasitoid species: Ooencyrtus fecundus, O. near fecundus, O. pityocampae and O. telenomicida, and compared their performance on their natural host, the variegated caper bug (CB) Stenozygum coloratum, and on an alternative, factitious host, the silk moth (SM) Bombyx mori. Survival was higher and development duration shorter in CB eggs, making the CB a better host for these congeners. However, adult longevity was generally longer for individuals that developed in SM eggs. Moreover, O. fecundus and O. pityocampae females that had developed in SM eggs displayed higher fecundity than all other female/host combinations. Survival also varied according to the age of the SM eggs: parasitoid survival rates were significantly higher in 9‐ to 12‐month‐old (post‐diapausing) eggs than in young (about 1 month old) ones. These results were probably influenced by differences among the egg sizes of the studied hosts. The number of non‐laying females and self‐superparasitism rates were exceptionally high in O. near fecundus. These findings suggest that SM eggs, and especially those which are being utilized after a long storage, could serve for mass rearing of the studied Ooencyrtus spp.
Driving with Mild Cognitive Impairment or Dementia: Cognitive Test Performance and Proxy Report of Daily Life Function in Older Women
Authors: Vaughan Leslie , Hogan Patricia E. , Rapp Stephen R. , Dugan Elizabeth , Marottoli Richard A. , Snively Beverly M. , Shumaker Sally A. , Sink Kaycee M. 
Published: September 2015

ObjectivesTo investigate associations between proxy report of cognitive and functional limitations and cognitive performance and current or former driving status in older women with mild cognitive impairment (MCI) and all‐cause dementia.DesignCross‐sectional data analysis of retrospectively identified older women with adjudicated MCI and all‐cause dementia in the Women's Health Initiative Memory Study—Epidemiology of Cognitive Health Outcomes (WHIMS‐ECHO).SettingAcademic medical center.ParticipantsWomen (mean age ± standard deviation 83.7 ± 3.5) adjudicated with MCI or dementia during Year 1, 2, 3, or 4 of the WHIMS‐ECHO follow‐up period (N = 385).MeasurementsThe telephone‐administered cognitive battery included tests of attention, verbal learning and memory, verbal fluency, executive function, working memory, and global cognitive function plus self‐report measures of depressive symptomatology. The Dementia Questionnaire (DQ) was administered to a knowledgeable proxy (family member, friend).ResultsSixty percent of women with MCI and 40% of those with dementia are current drivers. Proxy reports of functional limitations in instrumental activities of daily living (IADLs) are associated with current driving status in women with MCI, whereas performance‐based cognitive tests are not. In women with dementia, proxy reports of functional limitations in IADLs and performance‐based cognitive tests are associated with current driving status, as expected.ConclusionThese findings have clinical implications for the importance of evaluating driving concurrently with other instrumental functional abilities in MCI and dementia. Additional work is needed to determine whether proxy report of cognitive and functional impairments should help guide referrals for driving assessment and rehabilitation or counseling for driving transition.
Long‐lasting effect of NMDA receptor antagonist memantine on ethanol‐cue association and relapse
Authors: Vengeliene Valentina , Olevska Anastasia , Spanagel Rainer 
Published: September 2015

AbstractIt is well known that the glutamatergic system plays a crucial role in alcohol addiction and especially in relapse‐like behaviour. However, results of clinical studies on compounds that influence the activity of the glutamatergic system have been disappointing so far. The aim of our study was to establish treatment conditions under which the N‐methyl‐d‐aspartate receptor (NMDAR) antagonist memantine may produce more reliable treatment effect with respect to alcohol relapse‐like behaviour. For this purpose, male Wistar rats were trained to associate several discrete stimuli with ethanol delivery. Thereafter, half of the animals received a brief memory reactivation session followed by two administrations of 20 mg/kg of memantine, while the other half received the same treatment without memory reactivation. Afterwards, a cue‐induced ethanol‐seeking behaviour test was performed followed by repeated extinction sessions and a reacquisition test. Our data show that administration of memantine reduced responding on the ethanol‐associated lever in a cue‐induced ethanol‐seeking test. This reduction did not depend on whether or not a memory reactivation session was introduced prior to memantine administration. Following extinction, however, reacquisition of ethanol self‐administration was only impaired in the group where memantine was given after a short memory reactivation session, showing that this schedule of drug administration produced a long‐lasting disruption of the association between the conditioned stimuli and the delivery of ethanol. In conclusion, we show that memantine disrupted the drug‐cue association, which consequently interfered with relapse‐like behaviour supporting the possibility that memantine is a treatment option for alcoholism.
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Our data supports the possibility that memantine is a treatment option for alcoholism. However, the effectiveness of this drug seems to lie in its ability to disrupt conditioned behaviours and should be given in conjunction with exposure to conditioned drug stimuli.
Soluble amyloid precursor protein alpha inhibits tau phosphorylation through modulation of GSK3β signaling pathway
Authors: Deng Juan , Habib Ahsan , Obregon Demian F. , Barger Steven W. , Giunta Brian , Wang Yan‐Jiang , Hou Huayan , Sawmiller Darrell , Tan Jun 
Published: September 2015

AbstractWe recently found that sAPPα decreases amyloid‐beta generation by directly associating with β‐site amyloid precursor protein (APP)‐converting enzyme 1 (BACE1), thereby modulating APP processing. Because inhibition of BACE1 decreases glycogen synthase kinase 3 beta (GSK3β)‐mediated Alzheimer's disease (AD)‐like tau phosphorylation in AD patient‐derived neurons, we determined whether sAPPα also reduces GSK3β‐mediated tau phosphorylation. We initially found increased levels of inhibitory phosphorylation of GSK3β (Ser9) in primary neurons from sAPPα over‐expressing mice. Further, recombinant human sAPPα evoked the same phenomenon in SH‐SY5Y cells. Further, in SH‐SY5Y cells over‐expressing BACE1, and HeLa cells over‐expressing human tau, sAPPα reduced GSK3β activity and tau phosphorylation. Importantly, the reductions in GSK3β activity and tau phosphorylation elicited by sAPPα were prevented by BACE1 but not γ‐secretase inhibition. In accord, AD mice over‐expressing human sAPPα had less GSK3β activity and tau phosphorylation compared with controls. These results implicate a direct relationship between APP β‐processing and GSK3β‐mediated tau phosphorylation and further define the central role of sAPPα in APP autoregulation and AD pathogenesis.
imageHypothesized pathway for sAPPα‐mediated reduction of tau phosphorylation: Soluble amyloid precursor protein alpha (sAPPα) increases glycogen synthase kinase 3 beta (GSK3β) inhibitory phosphorylation by inhibiting β‐site APP‐converting enzyme 1 (BACE1) and followed by reduction of tau phosphorylation. BACE1 inhibition also results in a decrease of amyloid‐beta (Aβ) production. We believe these findings might provide a new strategy to use sAPPα, in treating both Aβ and tau pathology.
Deficiencies in Dermatologic Training in Pediatric Residency: Perspective of Pediatric Residency Program Directors
Authors: Khorsand Kate , Brandling‐Bennett Heather A. 
Published: September 2015

AbstractBackground/ObjectivesChildren with skin‐related problems commonly present to general pediatricians, and dermatology is among the top specialty areas that pediatricians have identified as having inadequate training to support their practice. This study was designed to document current opportunities for dermatologic training during pediatric residency and provides suggestions for improvement.MethodsPediatric residency program directors were contacted to participate in an online survey focusing on dermatologic training during pediatric residency. The survey was sent to 199 programs, from which 78 responses were received (response rate 39.2%). Required or elective rotations, other educational opportunities, and adequacy of dermatology training during pediatric residency were assessed and compared between institutions with zero, one, or two or more affiliated pediatric dermatologists.ResultsEighty‐four percent of pediatric residency programs offer clinical training in dermatology. This training is required in only 19% of programs and is elective in 73%. Fewer than one‐quarter of eligible residents participate in the elective option. Didactic dermatology lectures are available at all of the programs. Overall, only 6% of residency program directors felt that their graduating residents received very adequate training in dermatology and 26% felt their residents received inadequate training.ConclusionsExposure to dermatology clinics was perceived to be the most desirable training modality for pediatric residents, but a minority of residents receive this exposure. Many pediatric residency program directors felt that residents receive inadequate dermatology training, which indicates a need to address educational deficiencies. Supporting a pediatric dermatologist on staff and requiring a rotation in pediatric dermatology could improve dermatologic curricula for pediatric residents.
Facing up to Ignorance and Privilege: Philosophy of Whiteness as Public Intellectualism
Authors: MacMullan Terrance 
Published: September 2015

AbstractThis article offers an overview on current trends and future research possibilities within the philosophy of whiteness. It examines the sub‐field of the philosophy of whiteness within the context of the larger field of the philosophy of race in order to assess the viability and relevance of this field of study. Some of the topics on whiteness examined in the article include the problems of white ignorance and privilege, the invisibility of white supremacist racism to white people, and how all these problems can be understood either as examples of epistemologies of ignorance or as unexamined habits in the sense used by pragmatist philosophy. The article argues that the current state of this field calls for a greater emphasis on public intellectualism on whiteness that would incorporate many ideas that are widely accepted by critical race scholars into the under‐informed public discourse on race and whiteness. It also argues that the increasing prevalence of negative liberty movements in the United States should be examined in light of established research on the philosophy of whiteness.