Barriers and Facilitators to Implementing a Change Initiative in Long-Term Care Using the INTERACT® Quality Improvement Program.

PubMed

Tappen, Ruth M; Wolf, David G; Rahemi, Zahra; Engstrom, Gabriella; Rojido, Carolina; Shutes, Jill M; Ouslander, Joseph G

Implementation of major organizational change initiatives presents a challenge for long-term care leadership. Implementation of the INTERACT® (Interventions to Reduce Acute Care Transfers) quality improvement program, designed to improve the management of acute changes in condition and reduce unnecessary emergency department visits and hospitalizations of nursing home residents, serves as an example to illustrate the facilitators and barriers to major change in long-term care. As part of a larger study of the impact of INTERACT® on rates of emergency department visits and hospitalizations, staff of 71 nursing homes were called monthly to follow-up on their progress and discuss successful facilitating strategies and any challenges and barriers they encountered during the yearlong implementation period. Themes related to barriers and facilitators were identified. Six major barriers to implementation were identified: the magnitude and complexity of the change (35%), instability of facility leadership (27%), competing demands (40%), stakeholder resistance (49%), scarce resources (86%), and technical problems (31%). Six facilitating strategies were also reported: organization-wide involvement (68%), leadership support (41%), use of administrative authority (14%), adequate training (66%), persistence and oversight on the part of the champion (73%), and unfolding positive results (14%). Successful introduction of a complex change such as the INTERACT® quality improvement program in a long-term care facility requires attention to the facilitators and barriers identified in this report from those at the frontline.

Pharmacological Rescue of Long-Term Potentiation in Alzheimer Diseased Synapses

PubMed Central

Berchtold, Nicole C.; Lynch, Gary; Cotman, Carl W.

2017-01-01

Long-term potentiation (LTP) is an activity-dependent and persistent increase in synaptic transmission. Currently available techniques to measure LTP are time-intensive and require highly specialized expertise and equipment, and thus are not well suited for screening of multiple candidate treatments, even in animal models. To expand and facilitate the analysis of LTP, here we use a flow cytometry-based method to track chemically induced LTP by detecting surface AMPA receptors in isolated synaptosomes: fluorescence analysis of single-synapse long-term potentiation (FASS-LTP). First, we demonstrate that FASS-LTP is simple, sensitive, and models electrically induced LTP recorded in intact circuitries. Second, we conducted FASS-LTP analysis in two well-characterized Alzheimer's disease (AD) mouse models (3xTg and Tg2576) and, importantly, in cryopreserved human AD brain samples. By profiling hundreds of synaptosomes, our data provide the first direct evidence to support the idea that synapses from AD brain are intrinsically defective in LTP. Third, we used FASS-LTP for drug evaluation in human synaptosomes. Testing a panel of modulators of cAMP and cGMP signaling pathways, FASS-LTP identified vardenafil and Bay-73–6691 (phosphodiesterase-5 and -9 inhibitors, respectively) as potent enhancers of LTP in synaptosomes from AD cases. These results indicate that our approach could provide the basis for protocols to study LTP in both healthy and diseased human brains, a previously unattainable goal. SIGNIFICANCE STATEMENT Learning and memory depend on the ability of synapses to strengthen in response to activity. Long-term potentiation (LTP) is a rapid and persistent increase in synaptic transmission that is thought to be affected in Alzheimer's disease (AD). However, direct evidence of LTP deficits in human AD brain has been elusive, primarily due to methodological limitations. Here, we analyze LTP in isolated synapses from AD brain using a novel approach that allows

Social Isolation During Adolescence Strengthens Retention of Fear Memories and Facilitates Induction of Late-Phase Long-Term Potentiation.

PubMed

Liu, Ji-Hong; You, Qiang-Long; Wei, Mei-Dan; Wang, Qian; Luo, Zheng-Yi; Lin, Song; Huang, Lang; Li, Shu-Ji; Li, Xiao-Wen; Gao, Tian-Ming

2015-12-01

Social isolation during the vulnerable period of adolescence produces emotional dysregulation that often manifests as abnormal behavior in adulthood. The enduring consequence of isolation might be caused by a weakened ability to forget unpleasant memories. However, it remains unclear whether isolation affects unpleasant memories. To address this, we used a model of associative learning to induce the fear memories and evaluated the influence of isolation mice during adolescence on the subsequent retention of fear memories and its underlying cellular mechanisms. Following adolescent social isolation, we found that mice decreased their social interaction time and had an increase in anxiety-related behavior. Interestingly, when we assessed memory retention, we found that isolated mice were unable to forget aversive memories when tested 4 weeks after the original event. Consistent with this, we observed that a single train of high-frequency stimulation (HFS) enabled a late-phase long-term potentiation (L-LTP) in the hippocampal CA1 region of isolated mice, whereas only an early-phase LTP was observed with the same stimulation in the control mice. Social isolation during adolescence also increased brain-derived neurotrophic factor (BDNF) expression in the hippocampus, and application of a tropomyosin-related kinase B (TrkB) receptor inhibitor ameliorated the facilitated L-LTP seen after isolation. Together, our results suggest that adolescent isolation may result in mental disorders during adulthood and that this may stem from an inability to forget the unpleasant memories via BDNF-mediated synaptic plasticity. These findings may give us a new strategy to prevent mental disorders caused by persistent unpleasant memories.

The experience of facilitators and participants of long term condition self-management group programmes: A qualitative synthesis.

PubMed

Hughes, Stephen; Lewis, Sophie; Willis, Karen; Rogers, Anne; Wyke, Sally; Smith, Lorraine

2017-12-01

Our aim was to systematically review the qualitative literature about the experiences of both facilitators and participants in a range of group-based programmes to support the self-management of long-term conditions. We searched 7 databases using the terms 'self-management', 'group' and 'qualitative'. Full text articles meeting the inclusion criteria were retrieved for review. A thematic synthesis approach was used to analyse the studies. 2126 articles were identified and 24 were included for review. Group participants valued being with similar others and perceived peer support benefits. Facilitators (HCP and lay) had limited group specific training, were uncertain of purpose and prioritised education and medical conformity over supportive group processes and the promotion of self-management agency and engagement. Overall, studies prioritised positive descriptions. Group programmes' medical self-management focus may reduce their ability to contribute to patient-valued outcomes. Further research is needed to explore this disconnect. This review supports broadening the scope of group-based programmes to foreground shared learning, social support and development of agency. It is of relevance to developers and facilitators of group self-management programmes and their ability to address the burden of long-term conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Hippocampal Focal Knockout of CBP Affects Specific Histone Modifications, Long-Term Potentiation, and Long-Term Memory

PubMed Central

Barrett, Ruth M; Malvaez, Melissa; Kramar, Eniko; Matheos, Dina P; Arrizon, Abraham; Cabrera, Sara M; Lynch, Gary; Greene, Robert W; Wood, Marcelo A

2011-01-01

To identify the role of the histone acetyltransferase (HAT) CREB-binding protein (CBP) in neurons of the CA1 region of the hippocampus during memory formation, we examine the effects of a focal homozygous knockout of CBP on histone modifications, gene expression, synaptic plasticity, and long-term memory. We show that CBP is critical for the in vivo acetylation of lysines on histones H2B, H3, and H4. CBP's homolog p300 was unable to compensate for the loss of CBP. Neurons lacking CBP maintained phosphorylation of the transcription factor CREB, yet failed to activate CREB:CBP-mediated gene expression. Loss of CBP in dorsal CA1 of the hippocampus resulted in selective impairments to long-term potentiation and long-term memory for contextual fear and object recognition. Together, these results suggest a necessary role for specific chromatin modifications, selectively mediated by CBP in the consolidation of memories. PMID:21508930

Effect of agmatine on long-term potentiation in morphine-treated rats.

PubMed

Lu, Wei; Dong, Hua-Jin; Bi, Guo-Hua; Zhao, Yong-Qi; Yang, Zheng; Su, Rui-Bin; Li, Jin

2010-08-01

Agmatine is an endogenous amine derived from l-arginine that potentiates morphine analgesia and inhibits naloxone precipitated abstinent symptoms in morphine dependent rats. In this study, the effects of agmatine on long-term potentiation (LTP) in the lateral perforant path (LPP)-granule cell synapse of the rat dentate gyrus (DG) on saline or morphine-treated rats were investigated. Population spikes (PS), evoked by stimulation of the LPP, was recorded from DG region. Acute agmatine (2.5-10mg/kg, s.c.) treatment facilitated hippocampal LTP. Acute morphine (30mg/kg, s.c.) treatment significantly attenuated hippocampal LTP and agmatine (10mg/kg, s.c.) restored the amplitude of PS that was attenuated by morphine. Chronic morphine treatment resulted in the enhancement of hippocampal LTP, agmatine co-administered with morphine significantly attenuated the enhancement of morphine on hippocampal LTP. Imidazoline receptor antagonist idazoxan (5mg/kg, i.p.) reversed the effect of agmatine. These results suggest that agmatine attenuated the effect of morphine on hippocampal LTP, possibly through activation of imidazoline receptor. Crown Copyright 2010. Published by Elsevier Inc. All rights reserved.

Chronic treatment with ginsenoside Rg1 promotes memory and hippocampal long-term potentiation in middle-aged mice.

PubMed

Zhu, G; Wang, Y; Li, J; Wang, J

2015-04-30

Ginseng serves as a potential candidate for the treatment of aging-related memory decline or memory loss. However, the related mechanism is not fully understood. In this study, we applied an intraperitoneal injection of ginsenoside Rg1, an active compound from ginseng in middle-aged mice and detected memory improvement and the underlying mechanisms. Our results showed that a period of 30-day administration of ginsenoside Rg1 enhanced long-term memory in the middle-aged animals. Consistent with the memory improvement, ginsenoside Rg1 administration facilitated weak theta-burst stimulation (TBS)-induced long-term potentiation (LTP) in acute hippocampal slices from middle-aged animals. Ginsenoside Rg1 administration increased the dendritic apical spine numbers and area in the CA1 region. In addition, ginsenoside Rg1 administration up-regulated the expression of hippocampal p-AKT, brain-derived neurotrophic factor (BDNF), proBDNF and glutamate receptor 1 (GluR1), but not p-ERK. Interestingly, the phosphatase and tensin homolog deleted on chromosome ten (PTEN) inhibitor (bpV) mimicked the ginsenoside Rg1 effects, including increasing p-AKT expression, promoting hippocampal basal synaptic transmission, LTP and memory. Taken together, our data suggest that ginsenoside Rg1 treatment improves memory in middle-aged mice possibly through regulating the PI3K/AKT pathway, altering apical spines and facilitating hippocampal LTP. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Effectiveness of a program to facilitate recovery for people with long-term mental illness in Japan.

PubMed

Chiba, Rie; Miyamoto, Yuki; Kawakami, Norito; Harada, Naoko

2014-09-01

Recovery is defined as the process of developing new meaning and purpose in life as one grows beyond the catastrophic effects of mental illness. This study aimed to develop a program to facilitate recovery and examine its effectiveness in a randomized controlled trial. The program was developed with three components that enhance benefit finding, personal meaning, and a sense of happiness. Sixty-three participants with long-term mental illness were randomly allocated to the intervention group (n = 32) or the control group (n = 31). The intervention group attended eight 2-h group sessions, with one held every week. Recovery was assessed at baseline, post-intervention, and at a three-month follow-up. In the per-protocol analysis, after excluding those who dropped out, the intervention group showed significant improvement in recovery compared with the control group (P < 0.05). In the intention-to-treat analysis, a repeated measures analysis of variance did not show any significant intervention effect (time × group) (P > 0.05). The program had the potential to facilitate recovery. © 2013 Wiley Publishing Asia Pty Ltd.

Sustained transfer of knowledge to practice in long-term care: facilitators and barriers of a mental health learning initiative.

PubMed

Stolee, Paul; McAiney, Carrie A; Hillier, Loretta M; Harris, Diane; Hamilton, Pam; Kessler, Linda; Madsen, Victoria; Le Clair, J Kenneth

2009-01-01

This article explores facilitators and barriers to the impact and sustainability of a learning initiative to increase capacity of long-term care (LTC) homes to manage the mental health needs of older persons, through development of in-house Psychogeriatric Resource Persons (PRPs). Twenty interviews were conducted with LTC staff. Management support, particularly designation of time for PRP activities, development of PRP teams, and supportive learning strategies were significant factors affecting sustained knowledge transfer. Continuing education that is provided and evaluated on an ongoing basis, secures management commitment, is integrated within a broader system strategy, and provides on-the-job support has the greatest potential to affect care.

Fasting launches CRTC to facilitate long-term memory formation in Drosophila.

PubMed

Hirano, Yukinori; Masuda, Tomoko; Naganos, Shintaro; Matsuno, Motomi; Ueno, Kohei; Miyashita, Tomoyuki; Horiuchi, Junjiro; Saitoe, Minoru

2013-01-25

Canonical aversive long-term memory (LTM) formation in Drosophila requires multiple spaced trainings, whereas appetitive LTM can be formed after a single training. Appetitive LTM requires fasting prior to training, which increases motivation for food intake. However, we found that fasting facilitated LTM formation in general; aversive LTM formation also occurred after single-cycle training when mild fasting was applied before training. Both fasting-dependent LTM (fLTM) and spaced training-dependent LTM (spLTM) required protein synthesis and cyclic adenosine monophosphate response element-binding protein (CREB) activity. However, spLTM required CREB activity in two neural populations--mushroom body and DAL neurons--whereas fLTM required CREB activity only in mushroom body neurons. fLTM uses the CREB coactivator CRTC, whereas spLTM uses the coactivator CBP. Thus, flies use distinct LTM machinery depending on their hunger state.

The discovery of long-term potentiation.

PubMed

Lømo, Terje

2003-04-29

This paper describes circumstances around the discovery of long-term potentiation (LTP). In 1966, I had just begun independent work for the degree of Dr medicinae (PhD) in Per Andersen's laboratory in Oslo after an eighteen-month apprenticeship with him. Studying the effects of activating the perforant path to dentate granule cells in the hippocampus of anaesthetized rabbits, I observed that brief trains of stimuli resulted in increased efficiency of transmission at the perforant path-granule cell synapses that could last for hours. In 1968, Tim Bliss came to Per Andersen's laboratory to learn about the hippocampus and field potential recording for studies of possible memory mechanisms. The two of us then followed up my preliminary results from 1966 and did the experiments that resulted in a paper that is now properly considered to be the basic reference for the discovery of LTP.

The discovery of long-term potentiation.

PubMed Central

Lømo, Terje

2003-01-01

This paper describes circumstances around the discovery of long-term potentiation (LTP). In 1966, I had just begun independent work for the degree of Dr medicinae (PhD) in Per Andersen's laboratory in Oslo after an eighteen-month apprenticeship with him. Studying the effects of activating the perforant path to dentate granule cells in the hippocampus of anaesthetized rabbits, I observed that brief trains of stimuli resulted in increased efficiency of transmission at the perforant path-granule cell synapses that could last for hours. In 1968, Tim Bliss came to Per Andersen's laboratory to learn about the hippocampus and field potential recording for studies of possible memory mechanisms. The two of us then followed up my preliminary results from 1966 and did the experiments that resulted in a paper that is now properly considered to be the basic reference for the discovery of LTP. PMID:12740104

Early-life exposure to fibroblast growth factor-2 facilitates context-dependent long-term memory in developing rats.

PubMed

Graham, Bronwyn M; Richardson, Rick

2010-06-01

Fibroblast growth factor-2 (FGF2) is a potent neurotrophic factor that is involved in brain development and the formation of long-term memory. It has recently been shown that acute FGF2, administered at the time of learning, enhances long-term memory for contextual fear conditioning as well as extinction of conditioned fear in developing rats. As other research has shown that administering FGF2 on the first day of life leads to long-term morphological changes in the hippocampus, in the present study we investigated whether early life exposure to FGF2 affects contextual fear conditioning, and renewal following extinction, later in life. Experiment 1 demonstrated that a single injection of FGF2 on Postnatal Day (PND) 1 did not lead to any detectable changes in contextual fear conditioning in PND 16 or PND 23 rats. Experiments 2 and 3 demonstrated that 5 days of injections of FGF2 (from PND 1-5) facilitated contextual fear conditioning in PND 16 and PND 23 rats. Experiment 4 demonstrated that the observed facilitation of memory was not due to FGF2 increasing rats' sensitivity to foot shock. Experiment 5 showed that early life exposure to FGF2 did not affect learning about a discrete conditioned stimulus, but did allow PND 16 rats to use contextual information in more complex ways, leading to context-dependent extinction of conditioned fear. These results further implicate FGF2 as a critical signal involved in the development of learning and memory.

Endocannabinoid-Dependent Long-Term Potentiation of Synaptic Transmission at Rat Barrel Cortex.

PubMed

Maglio, Laura Eva; Noriega-Prieto, José Antonio; Maraver, Maria Jesús; Fernández de Sevilla, David

2018-05-01

Brain-derived neurotrophic factor (BDNF) plays a critical role in modulating plasticity in sensory cortices. Indeed, a BDNF-dependent long-term potentiation (LTP) at distal basal excitatory synapses of Layer 5 pyramidal neurons (L5PNs) has been demonstrated in disinhibited rat barrel cortex slices. Although it is well established that this LTP requires the pairing of excitatory postsynaptic potentials (PSPs) with Ca2+ spikes, its induction when synaptic inhibition is working remains unexplored. Here we show that low-frequency stimulation at basal dendrites of L5PNs is able to trigger a PSP followed by an action potential (AP) and a slow depolarization (termed PSP-Ca2+ response) in thalamocortical slices without blocking synaptic inhibition. We demonstrate that AP barrage-mediated release of endocannabinoids (eCBs) from the recorded L5PNs induces PSP-Ca2+ response facilitation and BDNF-dependent LTP. Indeed, this LTP requires the type 1 cannabinoid receptors activation, is prevented by postsynaptic intracellular 1,2-bis(2-aminophenoxy) ethane-N,N,N,N'-tetraacetic acid (BAPTA) or the anandamide membrane transporter inhibitor AM404, and only occurs in L5PNs neurons showing depolarization-induced suppression of inhibition. Additionally, electrical stimulation at the posteromedial thalamic nucleus induced similar response and LTP. These results reveal a novel form of eCB-dependent LTP at L5PNs that could be relevant in the processing of sensory information in the barrel cortex.

Heterosynaptic changes accompany long-term but not short-term potentiation of the perforant path in the anaesthetized rat.

PubMed

Abraham, W C; Bliss, T V; Goddard, G V

1985-06-01

Brief high-frequency trains of electrical stimulation delivered to the perforant path result in long-term potentiation (l.t.p.) of field potentials recorded extracellularly from granule cells of the dentate gyrus. L.t.p. of the population spike is often disproportionately greater than l.t.p. of the population excitatory post-synaptic potential (e.p.s.p.). We have investigated the basis of this effect in rats anaesthetized with sodium pentobarbitone. A series of graded stimuli were given before and after tetanization of the perforant path. From data obtained in this way, we plotted stimulus-response curves, and the relation (E-S curve) between the slope of the population e.p.s.p. (E) and the amplitude of the population spike (S). Curves relating spike onset latency to the slope of the e.p.s.p. were also constructed. Tetanization of the combined medial and lateral components of the perforant path led to long-term changes in the relation between the e.p.s.p. and the population spike. For a given e.p.s.p., the corresponding population spike was of greater amplitude and earlier onset. This E-S potentiation was marked by a shift to the left of the E-S amplitude curve and a downward displacement of the E-S latency curve. Tetanization of the lateral component of the perforant path had two long-term effects on responses evoked by test stimuli to the untetanized medial component: (1) long-term depression of the medial e.p.s.p. and (2) long-term E-S potentiation. The net result of these two heterosynaptically induced effects was to leave unaltered information transfer across medial perforant path-granule cell synapses; for a given test volley the e.p.s.p. was smaller, but because of E-S potentiation the population spike remained relatively unaffected. Short-term potentiation, which has a time course of only a few minutes and is presumed to be mediated by presynaptic mechanisms, was not accompanied by E-S potentiation or by corresponding changes in spike latency. Possible

Protein synthesis during acquisition of long-term facilitation is needed for the persistent loss of regulatory subunits of the Aplysia cAMP-dependent protein kinase.

PubMed Central

Bergold, P J; Sweatt, J D; Winicov, I; Weiss, K R; Kandel, E R; Schwartz, J H

1990-01-01

Depending on the number or the length of exposure, application of serotonin can produce either short-term or long-term presynaptic facilitation of Aplysia sensory-to-motor synapses. The cAMP-dependent protein kinase, a heterodimer of two regulatory and two catalytic subunits, has been shown to become stably activated only during long-term facilitation. Both acquisition of long-term facilitation and persistent activation of the kinase is blocked by anisomycin, an effective, reversible, and specific inhibitor of protein synthesis in Aplysia. We report here that 2-hr exposure of pleural sensory cells to serotonin lowers the concentration of regulatory subunits but does not change the concentration of catalytic subunits, as assayed 24 hr later; 5-min exposure to serotonin has no effect on either type of subunit. Increasing intracellular cAMP with a permeable analog of cAMP together with the phosphodiesterase inhibitor isobutyl methylxanthine also decreased regulatory subunits, suggesting that cAMP is the second messenger mediating serotonin action. Anisomycin blocked the loss of regulatory subunits only when applied with serotonin; application after the 2-hr treatment with serotonin had no effect. In the Aplysia accessory radula contractor muscle, prolonged exposure to serotonin or to the peptide transmitter small cardioactive peptide B, both of which produce large increases in intracellular cAMP, does not decrease regulatory subunits. This mechanism of regulating the cAMP-dependent protein kinase therefore may be specific to the nervous system. We conclude that during long-term facilitation, new protein is synthesized in response to the facilitatory stimulus, which changes the ratio of subunits of the cAMP-dependent protein kinase. This alteration in ratio could persistently activate the kinase and produce the persistent phosphorylation seen in long-term facilitated sensory cells. Images PMID:1692622

Long term potentiation, but not depression, in interlamellar hippocampus CA1.

PubMed

Sun, Duk-Gyu; Kang, Hyeri; Tetteh, Hannah; Su, Junfeng; Lee, Jihwan; Park, Sung-Won; He, Jufang; Jo, Jihoon; Yang, Sungchil; Yang, Sunggu

2018-03-26

Synaptic plasticity in the lamellar CA3 to CA1 circuitry has been extensively studied while interlamellar CA1 to CA1 connections have not yet received much attention. One of our earlier studies demonstrated that axons of CA1 pyramidal neurons project to neighboring CA1 neurons, implicating information transfer along a longitudinal interlamellar network. Still, it remains unclear whether long-term synaptic plasticity is present within this longitudinal CA1 network. Here, we investigate long-term synaptic plasticity between CA1 pyramidal cells, using in vitro and in vivo extracellular recordings and 3D holography glutamate uncaging. We found that the CA1-CA1 network exhibits NMDA receptor-dependent long-term potentiation (LTP) without direction or layer selectivity. By contrast, we find no significant long-term depression (LTD) under various LTD induction protocols. These results implicate unique synaptic properties in the longitudinal projection suggesting that the interlamellar CA1 network could be a promising structure for hippocampus-related information processing and brain diseases.

Role of platelet-activating factor in long-term potentiation of the rat medial vestibular nuclei.

PubMed

Grassi, S; Francescangeli, E; Goracci, G; Pettorossi, V E

1998-06-01

In rat brain stem slices, we investigated the role of platelet activating factor (PAF) in long-term potentiation (LTP) induced in the ventral part of the medial vestibular nuclei (MVN) by high-frequency stimulation (HFS) of the primary vestibular afferent. The synaptosomal PAF receptor antagonist, BN-52021 was administered before and after HFS. BN-52021 did not modify the vestibular potentials under basal conditions, but it reduced the magnitude of potentiation induced by HFS, which completely developed after the drug wash-out. The same effect was obtained by using CV-62091, a more potent PAF antagonist at microsomal binding sites, but with concentrations higher than those of BN-52021. By contrast both BN-52021 and CV-6209 had no effect on the potentiation once induced. This demonstrates that PAF is involved in the induction but not in the maintenance of vestibular long-term effect through activation of synaptosomal PAF receptors. In addition, we analyzed the effect of the PAF analogue, 1-O-hexadecyl-2-O- (methylcarbamyl)-sn-glycero-3-phosphocoline (MC-PAF) and the inactive PAF metabolite, 1-O-hexadecyl-sn-glycero-3-phosphocoline (Lyso-PAF) on vestibular responses. Our results show that MC-PAF, but not Lyso-PAF induced potentiation. This potentiation was prevented by D,L-2-amino 5-phosphonopentanoic acid, suggesting an involvement of N-methyl-D-aspartate receptors. Furthermore, under BN-52021 and CV-6209, the MC-PAF potentiation was reduced or abolished. The dose-effect curve of MC-PAF showed a shift to the right greater under BN-52021 than under CV-6209, confirming the main dependence of MC-PAF potentiation on the activation of synaptosomal PAF receptors. Our results suggest that PAF can be released in the MVN after the activation of postsynaptic mechanisms triggering LTP, and it may act as a retrograde messenger which activates the presynaptic mechanisms facilitating synaptic plasticity.

Oral administration of fisetin promotes the induction of hippocampal long-term potentiation in vivo.

PubMed

He, Wen-Bin; Abe, Kazuho; Akaishi, Tatsuhiro

2018-01-01

To explore memory enhancing effect of the flavonoid fisetin, we investigated the effect of oral administration of flavonoids on the induction of long-term potentiation (LTP) at hippocampal CA1 synapses of anesthetized rats. Among four flavonoids (fisetin, quercetin, luteolin and myricetin) tested, only fisetin significantly facilitated the induction of hippocampal LTP. The effect of oral fisetin was abolished by intracerebroventricular injection of U0126, an agent that was previously found to inhibit its effect in hippocampal slices in vitro. These results suggest that orally administered fisetin crosses the blood-brain barrier and promotes synaptic functions in the hippocampus. Copyright © 2018 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

Hippocampal CA1 Kindling but Not Long-Term Potentiation Disrupts Spatial Memory Performance

ERIC Educational Resources Information Center

Leung, L. Stan; Shen, Bixia

2006-01-01

Long-term synaptic enhancement in the hippocampus has been suggested to cause deficits in spatial performance. Synaptic enhancement has been reported after hippocampal kindling that induced repeated electrographic seizures or afterdischarges (ADs) and after long-term potentiation (LTP) defined as synaptic enhancement without ADs. We studied…

Calcitonin gene-related peptide erases the fear memory and facilitates long-term potentiation in the central nucleus of the amygdala in rats.

PubMed

Wu, Xin; Zhang, Jie-Ting; Liu, Jue; Yang, Si; Chen, Tao; Chen, Jian-Guo; Wang, Fang

2015-11-01

Calcitonin gene-related peptide (CGRP) is a 37 amino acid neuropeptide, which plays a critical role in the central nervous system. CGRP binds to G protein-coupled receptors, including CGRP1, which couples positively to adenylyl cyclase (AC) and protein kinase A (PKA) activation. CGRP and CGRP1 receptors are enriched in central nucleus of the amygdala (CeA), the main part of the amygdala, which regulates conditioned fear memories. Here, we reported the importance of CGRP and CGRP1 receptor for synaptic plasticity in the CeA and the extinction of fear memory in rats. Our electrophysiological and behavioral in vitro and in vivo results showed exogenous application of CGRP induced an immediate and lasting long-term potentiation in the basolateral nucleus of amygdala-CeA pathway, but not in the lateral nucleus of amygdala-CeA pathway, while bilateral intra-CeA infusion CGRP (0, 5, 13 and 21 μM/side) dose dependently enhanced fear memory extinction. The effects were blocked by CGRP1 receptor antagonist (CGRP8-37 ), N-methyl-d-aspartate receptors antagonist MK801 and PKA inhibitor H89. These results demonstrate that CGRP can lead to long-term potentiation of basolateral nucleus of amygdala-CeA pathway through a PKA-dependent postsynaptic mechanism that involved N-methyl-d-aspartate receptors and enhance the extinction of fear memory in rats. Together, the results strongly support a pivotal role of CGRP in the synaptic plasticity of CeA and extinction of fear memory. Calcitonin gene-related peptide (CGRP) plays an essential role in synaptic plasticity in the amygdala and fear memory. We found that CGRP-induced chemical long-term potentiation (LTP) in a dose-dependent way in the BLA-CeA (basolateral and central nucleus of amygdala, respectively) pathway and enhanced fear memory extinction in rats through a protein kinase A (PKA)-dependent postsynaptic mechanism that involved NMDA receptors. These results support a pivotal role of CGRP in amygdala. © 2015 International

Long-Term Economic Benefits of Preschool Services and the Potential Impact of Privatization.

ERIC Educational Resources Information Center

Kendall, Earline D.

This paper addresses the importance of a high quality preschool education for children living in poverty, the long-term effects of such an educational experience, the long-term economic benefits to the children enrolled and their families, and the potential impact of privatization on preschool services. The cost-effectiveness and cost-benefits of…

Dissecting the Components of Long-Term Potentiation

PubMed Central

Blundon, Jay A.; Zakharenko, Stanislav S.

2009-01-01

The formation of memories relies on plastic changes at synapses between neurons. Although the mechanisms of synaptic plasticity have been studied extensively over several decades, many aspects of this process remain controversial. The cellular locus of expression of long-term potentiation (LTP), a major form of synaptic plasticity, is one of the most important unresolved phenomena. In this article, we summarize some recent advances in this area made possible by the development of new imaging tools. These studies have demonstrated that LTP is compound in nature and consists of both presynaptic and postsynaptic components. We also review some features of presynaptic and postsynaptic changes during compound LTP. PMID:18940785

Sustained Transfer of Knowledge to Practice in Long-Term Care: Facilitators and Barriers of a Mental Health Learning Initiative

ERIC Educational Resources Information Center

Stolee, Paul; McAiney, Carrie A.; Hillier, Loretta M.; Harris, Diane; Hamilton, Pam; Kessler, Linda; Madsen, Victoria; Le Clair, J. Kenneth

2009-01-01

This article explores facilitators and barriers to the impact and sustainability of a learning initiative to increase capacity of long-term care (LTC) homes to manage the mental health needs of older persons, through development of in-house Psychogeriatric Resource Persons (PRPs). Twenty interviews were conducted with LTC staff. Management…

Fire effects on soils in Lake States forests: A compilation of published research to facilitate long-term investigations

Treesearch

Jessica Miesel; P. Goebel; R. Corace; David Hix; Randall Kolka; Brian Palik; David Mladenoff

2012-01-01

Fire-adapted forests of the Lake States region are poorly studied relative to those of the western and southeastern United States and our knowledge base of regional short- and long-term fire effects on soils is limited. We compiled and assessed the body of literature addressing fire effects on soils in Lake States forests to facilitate the re-measurement of previous...

Barriers and Facilitators of Transition from Pediatric to Adult Long-Term Follow-Up Care in Childhood Cancer Survivors.

PubMed

Rosenberg-Yunger, Zahava R S; Klassen, Anne F; Amin, Leila; Granek, Leeat; D'Agostino, Norma M; Boydell, Katherine M; Greenberg, Mark; Barr, Ronald D; Nathan, Paul C

2013-09-01

Despite the risk for late effects in adult survivors of cancer in childhood or adolescence, many survivors fail to transition from pediatric to adult long-term follow-up (LTFU) care. The purpose of this study was to identify the barriers and facilitators of transition from pediatric to adult LTFU care. In this qualitative study, 38 Canadian survivors of cancer in childhood or adolescence, currently aged 15-26 years, were interviewed using semi-structured, open-ended questions. Participants belonged to one of four groups: pre-transition (n=10), successful transition (n=11), failed to transition (n=7), and transitioned to an adult center but then dropped out of adult care (n=10). A constructivist grounded theory approach was used to analyze the interview data. This approach consisted of coding transcripts line by line to develop categories and using constant comparison to examine relationships within and across codes and categories. Interviewing continued until saturation was reached. Three interrelated themes were identified that affected the transition process: micro-level patient factors (e.g., due diligence, anxiety), meso-level support factors (e.g., family, friends), and macro-level system factors (e.g., appointments, communication, healthcare providers). Factors could act as facilitators to transition (e.g., family support), barriers to transition (e.g., difficulty booking appointments), or as both a barrier and a facilitator (e.g., anxiety). This study illustrates the interaction between multiple factors that facilitate and/or prevent transition from pediatric to adult LTFU cancer care. A number of recommendations are presented to address potential macro-level system barriers to successful transition.

Synapse Specificity of Long-Term Potentiation Breaks Down with Aging

ERIC Educational Resources Information Center

Ris, Laurence; Godaux, Emile

2007-01-01

Memory shows age-related decline. According to the current prevailing theoretical model, encoding of memories relies on modifications in the strength of the synapses connecting the different cells within a neuronal network. The selective increases in synaptic weight are thought to be biologically implemented by long-term potentiation (LTP). Here,…

Urethane inhibits genioglossal long-term facilitation in un-paralyzed anesthetized rats.

PubMed

Cao, Ying; Ling, Liming

2010-06-25

For approximately 3 decades, urethane has been (partially or solely) used as a successful anesthetic in numerous respiratory long-term facilitation (LTF) studies, which were performed on anesthetized, paralyzed, vagotomized and artificially ventilated animals of several different species. However, things become complicated when LTF of muscle activity is studied in un-paralyzed animals. For example, a commonly used acute intermittent hypoxia (AIH) protocol failed to induce muscle LTF in anesthetized, spontaneously breathing rats. But muscle LTF could be induced when hypoxic episode number was increased and/or anesthetics other than urethane were used. In these studies however, neither anesthetic nor paralysis was mentioned as a potential factor influencing AIH-induced muscle LTF. This study tested whether urethane inhibits AIH-induced genioglossal LTF (gLTF) in un-paralyzed ventilated rats, and if so, determined whether reducing urethane dose reverses this inhibition. Three groups of adult male Sprague-Dawley rats were anesthetized (Group 1: approximately 1.6 g kg(-1) urethane; Group 2: 50 mg kg(-1) alpha-chloralose +0.9-1.2 g kg(-1) urethane; Group 3: 0.9 g kg(-1) urethane +200-400 microg kg(-1) min(-1) alphaxalone), vagotomized and mechanically ventilated. Integrated genioglossus activity was measured before, during and after AIH (5 episodes of 3-min isocapnic 12% O(2), separated by 3-min hyperoxic intervals). The AIH-induced gLTF was absent in Group 1 rats (success rate was only approximately 1/7), but was present in Group 2 (in 10/12 rats) and Group 3 (in 11/11 rats) rats. The genioglossal response to hypoxia was not significantly different among the 3 groups. Collectively, these data suggest that urethane dose-dependently inhibits gLTF in un-paralyzed anesthetized rats. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Repeated pulses of serotonin required for long-term facilitation activate mitogen-activated protein kinase in sensory neurons of Aplysia

PubMed Central

Michael, Dan; Martin, Kelsey C.; Seger, Rony; Ning, Ming-Ming; Baston, Rene; Kandel, Eric R.

1998-01-01

Long-term facilitation of the connections between the sensory and motor neurons of the gill-withdrawal reflex in Aplysia requires five repeated pulses of serotonin (5-HT). The repeated pulses of 5-HT initiate a cascade of gene activation that leads ultimately to the growth of new synaptic connections. Several genes in this process have been identified, including the transcriptional regulators apCREB-1, apCREB-2, apC/EBP, and the cell adhesion molecule apCAM, which is thought to be involved in the formation of new synaptic connections. Here we report that the transcriptional regulators apCREB-2 and apC/EBP, as well as a peptide derived from the cytoplasmic domain of apCAM, are phosphorylated in vitro by Aplysia mitogen-activated protein kinase (apMAPK). We have cloned the cDNA encoding apMAPK and show that apMAPK activity is increased in sensory neurons treated with repeated pulses of 5-HT and by the cAMP pathway. These results suggest that apMAPK may participate with cAMP-dependent protein kinase during long-term facilitation in sensory cells by modifying some of the key elements involved in the consolidation of short- to long-lasting changes in synaptic strength. PMID:9465108

Compensation for PKMζ in long-term potentiation and spatial long-term memory in mutant mice.

PubMed

Tsokas, Panayiotis; Hsieh, Changchi; Yao, Yudong; Lesburguères, Edith; Wallace, Emma Jane Claire; Tcherepanov, Andrew; Jothianandan, Desingarao; Hartley, Benjamin Rush; Pan, Ling; Rivard, Bruno; Farese, Robert V; Sajan, Mini P; Bergold, Peter John; Hernández, Alejandro Iván; Cottrell, James E; Shouval, Harel Z; Fenton, André Antonio; Sacktor, Todd Charlton

2016-05-17

PKMζ is a persistently active PKC isoform proposed to maintain late-LTP and long-term memory. But late-LTP and memory are maintained without PKMζ in PKMζ-null mice. Two hypotheses can account for these findings. First, PKMζ is unimportant for LTP or memory. Second, PKMζ is essential for late-LTP and long-term memory in wild-type mice, and PKMζ-null mice recruit compensatory mechanisms. We find that whereas PKMζ persistently increases in LTP maintenance in wild-type mice, PKCι/λ, a gene-product closely related to PKMζ, persistently increases in LTP maintenance in PKMζ-null mice. Using a pharmacogenetic approach, we find PKMζ-antisense in hippocampus blocks late-LTP and spatial long-term memory in wild-type mice, but not in PKMζ-null mice without the target mRNA. Conversely, a PKCι/λ-antagonist disrupts late-LTP and spatial memory in PKMζ-null mice but not in wild-type mice. Thus, whereas PKMζ is essential for wild-type LTP and long-term memory, persistent PKCι/λ activation compensates for PKMζ loss in PKMζ-null mice.

Leptin: a potential anxiolytic by facilitation of fear extinction.

PubMed

Wang, Wei; Liu, Song-Lin; Li, Kuan; Chen, Yu; Jiang, Bo; Li, Yan-Kun; Xiao, Jun-Li; Yang, Si; Chen, Tao; Chen, Jian-Guo; Li, Jia-Geng; Wang, Fang

2015-05-01

Anxiety disorders are characterized by a deficient extinction of fear memory. Evidence is growing that leptin influences numerous neuronal functions. The aims of this study were to investigate the effects and the mechanism of leptin on fear extinction. Leptin (1 mg/kg, i.p) was applied to evaluate the anxiolytic effect in rat behavioral tests. Field potentials recording were used to investigate the changes in synaptic transmission in the thalamic-lateral amygadala (LA) pathway of rat. We found that leptin produced strong anxiolytic effects under basal condition and after acute stress. Systemic administration and intra-LA infusions of leptin facilitated extinction of conditioned fear responses. The antagonist of NMDA receptor, MK-801, blocked the effect of leptin on fear extinction completely. Furthermore, these effects of leptin on fear extinction were accompanied by a reversal of conditioning-induced synaptic potentiation in the LA. Leptin facilitated NMDA receptor-mediated synaptic transmission, and reversed amygdala long-term potentiation (LTP) in a dose-dependent manner in vitro, and this LTP depotentiation effect was mediated by NMDA receptor and MAPK signaling pathway. These results identify a key role of leptin in dampening fear conditioning-induced synaptic potentiation in the LA through NMDA receptor and indicate a new strategy for treating anxiety disorders. © 2015 John Wiley & Sons Ltd.

Learning modifies subsequent induction of long-term potentiation-like and long-term depression-like plasticity in human motor cortex.

PubMed

Ziemann, Ulf; Ilić, Tihomir V; Iliać, Tihomir V; Pauli, Christian; Meintzschel, Frank; Ruge, Diane

2004-02-18

Learning may alter rapidly the output organization of adult motor cortex. It is a long-held hypothesis that modification of synaptic strength along cortical horizontal connections through long-term potentiation (LTP) and long-term depression (LTD) forms one important mechanism for learning-induced cortical plasticity. Strong evidence in favor of this hypothesis was provided for rat primary motor cortex (M1) by showing that motor learning reduced subsequent LTP but increased LTD. Whether a similar relationship exists in humans is unknown. Here, we induced LTP-like and LTD-like plasticity in the intact human M1 by an established paired associative stimulation (PAS) protocol. PAS consisted of 200 pairs of electrical stimulation of the right median nerve, followed by focal transcranial magnetic stimulation of the hand area of the left M1 at an interval equaling the individual N20 latency of the median nerve somatosensory-evoked cortical potential (PAS(N20)) or N20-5 msec (PAS(N20-5)). PAS(N20) induced reproducibly a LTP-like long-lasting (>30 min) increase in motor-evoked potentials from the left M1 to a thumb abductor muscle of the right hand, whereas PAS(N20-5) induced a LTD-like decrease. Repeated fastest possible thumb abduction movements resulted in learning, defined by an increase in maximum peak acceleration of the practiced movements, and prevented subsequent PAS(N20)-induced LTP-like plasticity but enhanced subsequent PAS(N20-5)-induced LTD-like plasticity. The same number of repeated slow thumb abduction movements did not result in learning and had no effects on PAS-induced plasticity. Findings support the view that learning in human M1 occurs through LTP-like mechanisms.

Compensation for PKMζ in long-term potentiation and spatial long-term memory in mutant mice

PubMed Central

Tsokas, Panayiotis; Hsieh, Changchi; Yao, Yudong; Lesburguères, Edith; Wallace, Emma Jane Claire; Tcherepanov, Andrew; Jothianandan, Desingarao; Hartley, Benjamin Rush; Pan, Ling; Rivard, Bruno; Farese, Robert V; Sajan, Mini P; Bergold, Peter John; Hernández, Alejandro Iván; Cottrell, James E; Shouval, Harel Z; Fenton, André Antonio; Sacktor, Todd Charlton

2016-01-01

PKMζ is a persistently active PKC isoform proposed to maintain late-LTP and long-term memory. But late-LTP and memory are maintained without PKMζ in PKMζ-null mice. Two hypotheses can account for these findings. First, PKMζ is unimportant for LTP or memory. Second, PKMζ is essential for late-LTP and long-term memory in wild-type mice, and PKMζ-null mice recruit compensatory mechanisms. We find that whereas PKMζ persistently increases in LTP maintenance in wild-type mice, PKCι/λ, a gene-product closely related to PKMζ, persistently increases in LTP maintenance in PKMζ-null mice. Using a pharmacogenetic approach, we find PKMζ-antisense in hippocampus blocks late-LTP and spatial long-term memory in wild-type mice, but not in PKMζ-null mice without the target mRNA. Conversely, a PKCι/λ-antagonist disrupts late-LTP and spatial memory in PKMζ-null mice but not in wild-type mice. Thus, whereas PKMζ is essential for wild-type LTP and long-term memory, persistent PKCι/λ activation compensates for PKMζ loss in PKMζ-null mice. DOI: http://dx.doi.org/10.7554/eLife.14846.001 PMID:27187150

Long Latency Auditory Evoked Potential in Term and Premature Infants

PubMed Central

Didoné, Dayane Domeneghini; Garcia, Michele Vargas; da Silveira, Aron Ferreira

2013-01-01

Introduction The research in long latency auditory evokes potentials (LLAEP) in newborns is recent because of the cortical structure maturation, but studies note that these potentials may be evidenced at this age and could be considered as indicators of cognitive development. Purpose To research the exogenous potentials in term and premature infants during their first month of life. Materials and Methods The sample consisted of 25 newborns, 15 term and 10 premature infants. The infants with gestational age under 37 weeks were considered premature. To evaluate the cortical potentials, the infants remained in natural sleep. The LLAEPs were researched binaurally, through insertion earphones, with frequent /ba/ and rare /ga/ speech stimuli in the intensity of 80 dB HL (decibel hearing level). The frequent stimuli presented a total of 80% of the presentations, and the rare, 20%. The data were statistically analyzed. Results The average gestational age of the term infants was 38.9 weeks (± 1.3) and for the premature group, 33.9 weeks (± 1.6). It was possible to observe only the potentials P1 and N1 in both groups, but there was no statistically significant difference for the latencies of the components P1 and N1 (p > 0.05) between the groups. Conclusion It was possible to observe the exogenous components P1 and N1 of the cortical potentials in both term and preterm newborns of no more than 1 month of age. However, there was no difference between the groups. PMID:25992057

Potential breeding distributions of U.S. birds predicted with both short-term variability and long-term average climate data.

PubMed

Bateman, Brooke L; Pidgeon, Anna M; Radeloff, Volker C; Flather, Curtis H; VanDerWal, Jeremy; Akçakaya, H Resit; Thogmartin, Wayne E; Albright, Thomas P; Vavrus, Stephen J; Heglund, Patricia J

2016-12-01

Climate conditions, such as temperature or precipitation, averaged over several decades strongly affect species distributions, as evidenced by experimental results and a plethora of models demonstrating statistical relations between species occurrences and long-term climate averages. However, long-term averages can conceal climate changes that have occurred in recent decades and may not capture actual species occurrence well because the distributions of species, especially at the edges of their range, are typically dynamic and may respond strongly to short-term climate variability. Our goal here was to test whether bird occurrence models can be predicted by either covariates based on short-term climate variability or on long-term climate averages. We parameterized species distribution models (SDMs) based on either short-term variability or long-term average climate covariates for 320 bird species in the conterminous USA and tested whether any life-history trait-based guilds were particularly sensitive to short-term conditions. Models including short-term climate variability performed well based on their cross-validated area-under-the-curve AUC score (0.85), as did models based on long-term climate averages (0.84). Similarly, both models performed well compared to independent presence/absence data from the North American Breeding Bird Survey (independent AUC of 0.89 and 0.90, respectively). However, models based on short-term variability covariates more accurately classified true absences for most species (73% of true absences classified within the lowest quarter of environmental suitability vs. 68%). In addition, they have the advantage that they can reveal the dynamic relationship between species and their environment because they capture the spatial fluctuations of species potential breeding distributions. With this information, we can identify which species and guilds are sensitive to climate variability, identify sites of high conservation value where climate

Restoration of Long-Term Potentiation in Middle-Aged Hippocampus After Induction of Brain-Derived Neurotrophic Factor

PubMed Central

Rex, Christopher S.; Lauterborn, Julie C.; Lin, Ching-Yi; Kramár, Eniko A.; Rogers, Gary A.; Gall, Christine M.; Lynch, Gary

2006-01-01

Rex, Christopher S., Julie C. Lauterborn, Ching-Yi Lin, Eniko A. Kramár, Gary A. Rogers, Christine M. Gall, and Gary Lynch. Restoration of long-term potentiation in middle-aged hippocampus after induction of brain-derived neurotrophic factor. J Neurophysiol 96: 677-685, 2006. First published May 17, 2006; doi:10.1152/jn.00336.2006. Restoration of neuronal viability and synaptic plasticity through increased trophic support is widely regarded as a potential therapy for the cognitive declines that characterize aging. Previous studies have shown that in the hippocampal CA1 basal dendritic field deficits in the stabilization of long-term potentiation (LTP) are evident by middle age. The present study tested whether increasing endogenous brain-derived neurotrophic factor (BDNF) could reverse this age-related change. We report here that in middle-aged (8- to 10-mo-old) rats, in vivo treatments with a positive AMPA-type glutamate receptor modulator both increase BDNF protein levels in the cortical telencephalon and restore stabilization of basal dendritic LTP as assessed in acute hippocampal slices 18 h after the last drug treatment. These effects were not attributed to enhanced synaptic transmission or to facilitation of burst responses used to induce LTP. Increasing extracellular levels of BDNF by exogenous application to slices of middle-aged rats was also sufficient to rescue the stabilization of basal dendritic LTP. Finally, otherwise stable LTP in ampakine-treated middle-aged rats can be eliminated by infusion of the extracellular BDNF scavenger TrkB-Fc. Together these results indicate that increases in endogenous BDNF signaling can offset deficits in the postinduction processes that stabilize LTP. PMID:16707719

Subplots facilitate assessment of corn yield losses from weed competition in a long-term systems experiment

USDA-ARS?s Scientific Manuscript database

Weeds can potentially limit crop yield, particularly in organic systems where herbicide technologies are unavailable. Weedy and weed-free subplots were established within full plots of a long-term cropping systems experiment, the Farming Systems Project, at Beltsville, Maryland, USA, to determine t...

Dual Influence of Endocannabinoids on Long-Term Potentiation of Synaptic Transmission

PubMed Central

Silva-Cruz, Armando; Carlström, Mattias; Ribeiro, Joaquim A.; Sebastião, Ana M.

2017-01-01

Cannabinoid receptor 1 (CB1R) is widely distributed in the central nervous system, in excitatory and inhibitory neurons, and in astrocytes. CB1R agonists impair cognition and prevent long-term potentiation (LTP) of synaptic transmission, but the influence of endogenously formed cannabinoids (eCBs) on hippocampal LTP remains ambiguous. Based on the knowledge that eCBs are released upon high frequency neuronal firing, we hypothesized that the influence of eCBs upon LTP could change according to the paradigm of LTP induction. We thus tested the influence of eCBs on hippocampal LTP using two θ-burst protocols that induce either a weak or a strong LTP. LTP induced by a weak-θ-burst protocol is facilitated while preventing the endogenous activation of CB1Rs. In contrast, the same procedures lead to inhibition of LTP induced by the strong-θ-burst protocol, suggestive of a facilitatory action of eCBs upon strong LTP. Accordingly, an inhibitor of the metabolism of the predominant eCB in the hippocampus, 2-arachidonoyl-glycerol (2-AG), facilitates strong LTP. The facilitatory action of endogenous CB1R activation does not require the activity of inhibitory A1 adenosine receptors, is not affected by inhibition of astrocytic metabolism, but involves inhibitory GABAergic transmission. The continuous activation of CB1Rs via exogenous cannabinoids, or by drugs known to prevent metabolism of the non-prevalent hippocampal eCB, anandamide, inhibited LTP. We conclude that endogenous activation of CB1Rs by physiologically formed eCBs exerts a fine-tune homeostatic control of LTP in the hippocampus, acting as a high-pass filter, therefore likely reducing the signal-to-noise ratio of synaptic strengthening. PMID:29311928

Acute stress causes rapid synaptic insertion of Ca2+-permeable AMPA receptors to facilitate long-term potentiation in the hippocampus

PubMed Central

Jo, Jihoon; Hogg, Ellen L.; Piers, Thomas; Kim, Dong-Hyun; Seaton, Gillian; Seok, Heon; Bru-Mercier, Gilles; Son, Gi Hoon; Regan, Philip; Hildebrandt, Lars; Waite, Eleanor; Kim, Byeong-Chae; Kerrigan, Talitha L.; Kim, Kyungjin; Whitcomb, Daniel J.; Lightman, Stafford L.

2013-01-01

The neuroendocrine response to episodes of acute stress is crucial for survival whereas the prolonged response to chronic stress can be detrimental. Learning and memory are particularly susceptible to stress with cognitive deficits being well characterized consequences of chronic stress. Although there is good evidence that acute stress can enhance cognitive performance, the mechanism(s) for this are unclear. We find that hippocampal slices, either prepared from rats following 30 min restraint stress or directly exposed to glucocorticoids, exhibit an N-methyl-d-aspartic acid receptor-independent form of long-term potentiation. We demonstrate that the mechanism involves an NMDA receptor and PKA-dependent insertion of Ca2+-permeable AMPA receptors into synapses. These then trigger the additional NMDA receptor-independent form of LTP during high frequency stimulation. PMID:24271563

Long-term moderate elevation of corticosterone facilitates avian food-caching behaviour and enhances spatial memory.

PubMed

Pravosudov, Vladimir V

2003-12-22

It is widely assumed that chronic stress and corresponding chronic elevations of glucocorticoid levels have deleterious effects on animals' brain functions such as learning and memory. Some animals, however, appear to maintain moderately elevated levels of glucocorticoids over long periods of time under natural energetically demanding conditions, and it is not clear whether such chronic but moderate elevations may be adaptive. I implanted wild-caught food-caching mountain chickadees (Poecile gambeli), which rely at least in part on spatial memory to find their caches, with 90-day continuous time-release corticosterone pellets designed to approximately double the baseline corticosterone levels. Corticosterone-implanted birds cached and consumed significantly more food and showed more efficient cache recovery and superior spatial memory performance compared with placebo-implanted birds. Thus, contrary to prevailing assumptions, long-term moderate elevations of corticosterone appear to enhance spatial memory in food-caching mountain chickadees. These results suggest that moderate chronic elevation of corticosterone may serve as an adaptation to unpredictable environments by facilitating feeding and food-caching behaviour and by improving cache-retrieval efficiency in food-caching birds.

Learning, memory and long-term potentiation are altered in Nedd4 heterozygous mice.

PubMed

Camera, Daria; Coleman, Harold A; Parkington, Helena C; Jenkins, Trisha A; Pow, David V; Boase, Natasha; Kumar, Sharad; Poronnik, Philip

2016-04-15

The consolidation of short-term memory into long-term memory involves changing protein level and activity for the synaptic plasticity required for long-term potentiation (LTP). AMPA receptor trafficking is a key determinant of LTP and recently ubiquitination by Nedd4 has been shown to play an important role via direct action on the GluA1 subunit, although the physiological relevance of these findings are yet to be determined. We therefore investigated learning and memory in Nedd4(+/-) mice that have a 50% reduction in levels of Nedd4. These mice showed decreased long-term spatial memory as evidenced by significant increases in the time taken to learn the location of and subsequently find a platform in the Morris water maze. In contrast, there were no significant differences between Nedd4(+/+) and Nedd4(+/-) mice in terms of short-term spatial memory in a Y-maze test. Nedd4(+/-) mice also displayed a significant reduction in post-synaptic LTP measured in hippocampal brain slices. Immunofluorescence of Nedd4 in the hippocampus confirmed its expression in hippocampal neurons of the CA1 region. These findings indicate that reducing Nedd4 protein by 50% significantly impairs LTP and long-term memory thereby demonstrating an important role for Nedd4 in these processes. Copyright © 2016 Elsevier B.V. All rights reserved.

Mobile phone messaging for facilitating self-management of long-term illnesses.

PubMed

de Jongh, Thyra; Gurol-Urganci, Ipek; Vodopivec-Jamsek, Vlasta; Car, Josip; Atun, Rifat

2012-12-12

Long-term illnesses affect a significant proportion of the population in developed and developing countries. Mobile phone messaging applications, such as Short Message Service (SMS) and Multimedia Message Service (MMS), may present convenient, cost-effective ways of supporting self-management and improving patients' self-efficacy skills through, for instance, medication reminders, therapy adjustments or supportive messages. To assess the effects of mobile phone messaging applications designed to facilitate self-management of long-term illnesses, in terms of impact on health outcomes and patients' capacity to self-manage their condition. Secondary objectives include assessment of: user evaluation of the intervention; health service utilisation and costs; and possible risks and harms associated with the intervention. We searched the Cochrane Central Register of Controlled Trials (CENTRAL,The Cochrane Library 2009, Issue 2), MEDLINE (OvidSP) (January 1993 to June 2009), EMBASE (OvidSP) (January 1993 to June 2009), PsycINFO (OvidSP) (January 1993 to June 2009), CINAHL (EbscoHOST) (January 1993 to June 2009), LILACS (January 1993 to June 2009) and African Health Anthology (January 1993 to June 2009).We also reviewed grey literature (including trial registers) and reference lists of articles. We included randomised controlled trials (RCTs), quasi-randomised controlled trials (QRCTs), controlled before-after (CBA) studies, or interrupted time series (ITS) studies with at least three time points before and after the intervention. We selected only studies where it was possible to assess the effects of mobile phone messaging independent of other technologies or interventions. Two review authors independently assessed all studies against the inclusion criteria, with any disagreements resolved by a third review author. Study design features, characteristics of target populations, interventions and controls, and results data were extracted by two review authors and confirmed by

Long-term course of opioid addiction.

PubMed

Hser, Yih-Ing; Evans, Elizabeth; Grella, Christine; Ling, Walter; Anglin, Douglas

2015-01-01

Opioid addiction is associated with excess mortality, morbidities, and other adverse conditions. Guided by a life-course framework, we review the literature on the long-term course of opioid addiction in terms of use trajectories, transitions, and turning points, as well as other factors that facilitate recovery from addiction. Most long-term follow-up studies are based on heroin addicts recruited from treatment settings (mostly methadone maintenance treatment), many of whom are referred by the criminal justice system. Cumulative evidence indicates that opioid addiction is a chronic disorder with frequent relapses. Longer treatment retention is associated with a greater likelihood of abstinence, whereas incarceration is negatively related to subsequent abstinence. Over the long term, the mortality rate of opioid addicts (overdose being the most common cause) is about 6 to 20 times greater than that of the general population; among those who remain alive, the prevalence of stable abstinence from opioid use is low (less than 30% after 10-30 years of observation), and many continue to use alcohol and other drugs after ceasing to use opioids. Histories of sexual or physical abuse and comorbid mental disorders are associated with the persistence of opioid use, whereas family and social support, as well as employment, facilitates recovery. Maintaining opioid abstinence for at least five years substantially increases the likelihood of future stable abstinence. Recent advances in pharmacological treatment options (buprenorphine and naltrexone) include depot formulations offering longer duration of medication; their impact on the long-term course of opioid addiction remains to be assessed.

Intermittent hypercapnic hypoxia during sleep does not induce ventilatory long-term facilitation in healthy males.

PubMed

Deacon, Naomi L; McEvoy, R Doug; Stadler, Daniel L; Catcheside, Peter G

2017-09-01

Intermittent hypoxia-induced ventilatory neuroplasticity is likely important in obstructive sleep apnea pathophysiology. Although concomitant CO 2 levels and arousal state critically influence neuroplastic effects of intermittent hypoxia, no studies have investigated intermittent hypercapnic hypoxia effects during sleep in humans. Thus the purpose of this study was to investigate if intermittent hypercapnic hypoxia during sleep induces neuroplasticity (ventilatory long-term facilitation and increased chemoreflex responsiveness) in humans. Twelve healthy males were exposed to intermittent hypercapnic hypoxia (24 × 30 s episodes of 3% CO 2 and 3.0 ± 0.2% O 2 ) and intermittent medical air during sleep after 2 wk washout period in a randomized crossover study design. Minute ventilation, end-tidal CO 2 , O 2 saturation, breath timing, upper airway resistance, and genioglossal and diaphragm electromyograms were examined during 10 min of stable stage 2 sleep preceding gas exposure, during gas and intervening room air periods, and throughout 1 h of room air recovery. There were no significant differences between conditions across time to indicate long-term facilitation of ventilation, genioglossal or diaphragm electromyogram activity, and no change in ventilatory response from the first to last gas exposure to suggest any change in chemoreflex responsiveness. These findings contrast with previous intermittent hypoxia studies without intermittent hypercapnia and suggest that the more relevant gas disturbance stimulus of concomitant intermittent hypercapnia frequently occurring in sleep apnea influences acute neuroplastic effects of intermittent hypoxia. These findings highlight the need for further studies of intermittent hypercapnic hypoxia during sleep to clarify the role of ventilatory neuroplasticity in the pathophysiology of sleep apnea. NEW & NOTEWORTHY Both arousal state and concomitant CO 2 levels are known modulators of the effects of intermittent hypoxia on

Long-term effect of set potential on biocathodes in microbial fuel cells: electrochemical and phylogenetic characterization.

PubMed

Xia, Xue; Sun, Yanmei; Liang, Peng; Huang, Xia

2012-09-01

The long-term effect of set potential on oxygen reducing biocathodes was investigated in terms of electrochemical and biological characteristics. Three biocathodes were poised at 200, 60 and -100 mV vs. saturated calomel electrode (SCE) for 110 days, including the first 17 days for startup. Electrochemical analyses showed that 60 mV was the optimum potential during long-term operation. The performance of all the biocathodes kept increasing after startup, suggesting a period longer than startup time needed to make potential regulation more effective. The inherent characteristics without oxygen transfer limitation were studied. Different from short-term regulation, the amounts of biomass were similar while the specific electrochemical activity was significantly influenced by potential. Moreover, potential showed a strong selection for cathode bacteria. Clones 98% similar with an uncultured Bacteroidetes bacterium clone CG84 accounted for 75% to 80% of the sequences on the biocathodes that showed higher electrochemical activity (60 and -100 mV). Copyright © 2012 Elsevier Ltd. All rights reserved.

GluA2-dependent AMPA receptor endocytosis and the decay of early and late long-term potentiation: possible mechanisms for forgetting of short- and long-term memories.

PubMed

Hardt, Oliver; Nader, Karim; Wang, Yu-Tian

2014-01-05

The molecular processes involved in establishing long-term potentiation (LTP) have been characterized well, but the decay of early and late LTP (E-LTP and L-LTP) is poorly understood. We review recent advances in describing the mechanisms involved in maintaining LTP and homeostatic plasticity. We discuss how these phenomena could relate to processes that might underpin the loss of synaptic potentiation over time, and how they might contribute to the forgetting of short-term and long-term memories. We propose that homeostatic downscaling mediates the loss of E-LTP, and that metaplastic parameters determine the decay rate of L-LTP, while both processes require the activity-dependent removal of postsynaptic GluA2-containing AMPA receptors.

Synaptic characteristics with strong analog potentiation, depression, and short-term to long-term memory transition in a Pt/CeO2/Pt crossbar array structure

NASA Astrophysics Data System (ADS)

Kim, Hyung Jun; Park, Daehoon; Yang, Paul; Beom, Keonwon; Kim, Min Ju; Shin, Chansun; Kang, Chi Jung; Yoon, Tae-Sik

2018-06-01

A crossbar array of Pt/CeO2/Pt memristors exhibited the synaptic characteristics such as analog, reversible, and strong resistance change with a ratio of ∼103, corresponding to wide dynamic range of synaptic weight modulation as potentiation and depression with respect to the voltage polarity. In addition, it presented timing-dependent responses such as paired-pulse facilitation and the short-term to long-term memory transition by increasing amplitude, width, and repetition number of voltage pulse and reducing the interval time between pulses. The memory loss with a time was fitted with a stretched exponential relaxation model, revealing the relation of memory stability with the input stimuli strength. The resistance change was further enhanced but its stability got worse as increasing measurement temperature, indicating that the resistance was changed as a result of voltage- and temperature-dependent electrical charging and discharging to alter the energy barrier for charge transport. These detailed synaptic characteristics demonstrated the potential of crossbar array of Pt/CeO2/Pt memristors as artificial synapses in highly connected neuron-synapse network.

Synaptic characteristics with strong analog potentiation, depression, and short-term to long-term memory transition in a Pt/CeO2/Pt crossbar array structure.

PubMed

Kim, Hyung Jun; Park, Daehoon; Yang, Paul; Beom, Keonwon; Kim, Min Ju; Shin, Chansun; Kang, Chi Jung; Yoon, Tae-Sik

2018-06-29

A crossbar array of Pt/CeO 2 /Pt memristors exhibited the synaptic characteristics such as analog, reversible, and strong resistance change with a ratio of ∼10 3 , corresponding to wide dynamic range of synaptic weight modulation as potentiation and depression with respect to the voltage polarity. In addition, it presented timing-dependent responses such as paired-pulse facilitation and the short-term to long-term memory transition by increasing amplitude, width, and repetition number of voltage pulse and reducing the interval time between pulses. The memory loss with a time was fitted with a stretched exponential relaxation model, revealing the relation of memory stability with the input stimuli strength. The resistance change was further enhanced but its stability got worse as increasing measurement temperature, indicating that the resistance was changed as a result of voltage- and temperature-dependent electrical charging and discharging to alter the energy barrier for charge transport. These detailed synaptic characteristics demonstrated the potential of crossbar array of Pt/CeO 2 /Pt memristors as artificial synapses in highly connected neuron-synapse network.

Facilitating long-term changes in student approaches to learning science.

PubMed

Buchwitz, Brian J; Beyer, Catharine H; Peterson, Jon E; Pitre, Emile; Lalic, Nevena; Sampson, Paul D; Wakimoto, Barbara T

2012-01-01

Undergraduates entering science curricula differ greatly in individual starting points and learning needs. The fast pace, high enrollment, and high stakes of introductory science courses, however, limit students' opportunities to self-assess and modify learning strategies. The University of Washington's Biology Fellows Program (BFP) intervenes through a 20-session, premajors course that introduces students to the rigor expected of bioscience majors and assists their development as science learners. This study uses quantitative and qualitative approaches to assess whether the 2007-2009 BFP achieved its desired short- and long-term impacts on student learning. Adjusting for differences in students' high school grade point average and Scholastic Aptitude Test scores, we found that participation in the BFP was associated with higher grades in two subsequent gateway biology courses, across multiple quarters and instructors. Two to 4 yr after participating in the program, students attributed changes in how they approached learning science to BFP participation. They reported having learned to "think like a scientist" and to value active-learning strategies and learning communities. In addition, they reported having developed a sense of belonging in bioscience communities. The achievement of long-term impacts for a short-term instructional investment suggests a practical means to prepare diverse students for the rigors of science curricula.

Facilitating Long-Term Changes in Student Approaches to Learning Science

PubMed Central

Buchwitz, Brian J.; Beyer, Catharine H.; Peterson, Jon E.; Pitre, Emile; Lalic, Nevena; Sampson, Paul D.; Wakimoto, Barbara T.

2012-01-01

Undergraduates entering science curricula differ greatly in individual starting points and learning needs. The fast pace, high enrollment, and high stakes of introductory science courses, however, limit students’ opportunities to self-assess and modify learning strategies. The University of Washington's Biology Fellows Program (BFP) intervenes through a 20-session, premajors course that introduces students to the rigor expected of bioscience majors and assists their development as science learners. This study uses quantitative and qualitative approaches to assess whether the 2007–2009 BFP achieved its desired short- and long-term impacts on student learning. Adjusting for differences in students’ high school grade point average and Scholastic Aptitude Test scores, we found that participation in the BFP was associated with higher grades in two subsequent gateway biology courses, across multiple quarters and instructors. Two to 4 yr after participating in the program, students attributed changes in how they approached learning science to BFP participation. They reported having learned to “think like a scientist” and to value active-learning strategies and learning communities. In addition, they reported having developed a sense of belonging in bioscience communities. The achievement of long-term impacts for a short-term instructional investment suggests a practical means to prepare diverse students for the rigors of science curricula. PMID:22949424

Different contributions of platelet-activating factor and nitric oxide in long-term potentiation of the rat medial vestibular nuclei.

PubMed

Pettorossi, V E; Grassi, S

2001-01-01

In rat brainstem slices, we investigated the differential role of nitric oxide (NO) and platelet-activating factor (PAF) in long-term potentiation (LTP) induced in the ventral portion of the medial vestibular nuclei (MVN) by high-frequency stimulation (HFS) of the primary vestibular afferents. The NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (carboxy-PTIO) and the PAF receptor antagonist ginkgolide B (BN-52021) were administered before and after induction of potentiation. The effect of carboxy-PTIO was to completely prevent LTP. By contrast, BN-52021 only reduced the amplitude of HFS potentiation, which could develop fully at the drug washout or decline to zero, becoming a short-term phenomenon, in the case of long-lasting PAF receptor block. Both drugs, when given after HFS, had no effect on the already established potentiation, but whilst BN-52021 showed an influence within 5 min of the LTP induction, carboxy-PTIO did not affect the response once HFS was delivered. Moreover, we showed that the NO donor, sodium nitroprusside, and methylcarbamyl PAF (mc-PAF) induced LTP which was associated with an increase in glutamate release as shown by reduction in the paired-pulse facilitation ratio. The mc-PAF LTP was prevented by the NO scavenger, while NO LTP was only reduced by BN-52021. We suggest that NO and PAF are implicated as retrograde messengers in two different phases of vestibular LTP: NO in the induction phase; and PAF in the full expression phase.

Facilitating Long-Term Retention of Vocabulary: The Second-Hand Cloze.

ERIC Educational Resources Information Center

Laufer, Batia; Osimo, Helen

1991-01-01

Investigates whether the consistent use of a vocabulary reinforcement technique referred to as "second-hand cloze" can result in a significant improvement in long-term retention of words. It is suggested that, although the second-hand cloze embodies some characteristics of other memorization techniques, it also overcomes their shortcomings. (21…

Virtual Models of Long-Term Care

ERIC Educational Resources Information Center

Phenice, Lillian A.; Griffore, Robert J.

2012-01-01

Nursing homes, assisted living facilities and home-care organizations, use web sites to describe their services to potential consumers. This virtual ethnographic study developed models representing how potential consumers may understand this information using data from web sites of 69 long-term-care providers. The content of long-term-care web…

Estradiol and the Relationship between Dendritic Spines, NR2B Containing NMDA Receptors, and the Magnitude of Long-Term Potentiation at Hippocampal CA3-CA1 Synapses

PubMed Central

Smith, Caroline C.; Vedder, Lindsey C.; McMahon, Lori L.

2009-01-01

Summary When circulating estrogen levels decline as a natural consequence of menopause and aging in women, there is an increased incidence of deficits in working memory. In many cases, these deficits are rescued by estrogen replacement therapy. These clinical data therefore highlight the importance of defining the biological pathways linking estrogen to the cellular substrates of learning and memory. It has been known for nearly two decades that estrogen enhances dendritic spine density on apical dendrites of CA1 pyramidal cells in hippocampus, a brain region required for learning. Interestingly, at synapses between CA3-CA1 pyramidal cells, estrogen has also been shown to enhance synaptic NMDA receptor current and the magnitude of long term potentiation, a cellular correlate of learning and memory. Given that synapse density, NMDAR function, and long term potentiation at CA3-CA1 synapses in hippocampus are associated with normal learning, it is likely that modulation of these parameters by estrogen facilitates the improvement in learning observed in rats, primates and humans following estrogen replacement. To facilitate the design of clinical strategies to potentially prevent or reverse the age-related decline in learning and memory during menopause, the relationship between the estrogen-induced morphological and functional changes in hippocampus must be defined and the role these changes play in facilitating learning must be elucidated. The aim of this report is to provide a summary of the proposed mechanisms by which this hormone increases synaptic function and in doing so, it briefly addresses potential mechanisms contributing to the estrogen-induced increase in synaptic morphology and plasticity, as well as important future directions. PMID:19596521

Surprises and insights from long-term aquatic datasets and experiments

Treesearch

Walter K. Dodds; Christopher T. Robinson; Evelyn E. Gaiser; Gretchen J.A. Hansen; Heather Powell; Joseph M. Smith; Nathaniel B. Morse; Sherri L. Johnson; Stanley V. Gregory; Tisza Bell; Timothy K. Kratz; William H. McDowell

2012-01-01

Long-term research on freshwater ecosystems provides insights that can be difficult to obtain from other approaches. Widespread monitoring of ecologically relevant water-quality parameters spanning decades can facilitate important tests of ecological principles. Unique long-term data sets and analytical tools are increasingly available, allowing for powerful and...

Exogenous glutamate induces short and long-term potentiation in the rat medial vestibular nuclei.

PubMed

Grassi, S; Frondaroli, A; Pessia, M; Pettorossi, V E

2001-08-08

In rat brain stem slices, high concentrations of exogenous glutamate induce long-term potentiation (LTP) of the field potentials evoked in the medial vestibular nuclei (MVN) by vestibular afferent stimulation. At low concentrations, glutamate can also induce short-term potentiation (STP), indicating that LTP and STP are separate events depending on the level of glutamatergic synapse activation. LTP and STP are prevented by blocking NMDA receptors and nitric oxide (NO) synthesis. Conversely, blocking platelet-activating factor (PAF) and group I metabotropic glutamate receptors only prevents the full development of LTP. Moreover, in the presence of blocking agents, glutamate causes transient inhibition, suggesting that when potentiation is impeded, exogenous glutamate can activate presynaptic mechanisms that reduce glutamate release.

Long-term potentiation in the rat medial vestibular nuclei depends on locally synthesized 17beta-estradiol.

PubMed

Grassi, Silvarosa; Frondaroli, Adele; Dieni, Cristina; Scarduzio, Mariangela; Pettorossi, Vito E

2009-08-26

In male rat brainstem slices, we investigated the involvement of locally synthesized 17beta-estradiol (E(2)) in the induction in the medial vestibular nucleus (MVN) of long-term potentiation (LTP) by high-frequency stimulation (HFS) of the primary vestibular afferents. We demonstrated that the blockade of aromatase by letrozole or of E(2) receptors (ERalpha and ERbeta) by ICI 182,780 prevented the HFS-induced LTP of the N1 wave of the evoked field potential (FP) without affecting baseline responses. Only prolonged afferent activation could induce low LTP. In contrast, HFS applied under a combined blockade of GABA(A) receptors and aromatase or ERs was still able to induce LTP, but it was significantly lower and slower. These findings demonstrate that E(2) does not have a tonic influence on the activity of the MVN neurons and provide the first evidence of the crucial role played by local synthesis of E(2) in inducing LTP. We suggest that the synthesis of E(2) occurs after aromatase activation during HFS and facilitates the development of vestibular synaptic plasticity by influencing glutamate and GABA transmission.

Improved spatial learning is associated with increased hippocampal but not prefrontal long-term potentiation in mGluR4 knockout mice.

PubMed

Iscru, E; Goddyn, H; Ahmed, T; Callaerts-Vegh, Z; D'Hooge, R; Balschun, D

2013-08-01

Although much information about metabotropic glutamate receptors (mGluRs) and their role in normal and pathologic brain function has been accumulated during the last decades, the role of group III mGluRs is still scarcely documented. Here, we examined mGluR4 knockout mice for types of behavior and synaptic plasticity that depend on either the hippocampus or the prefrontal cortex (PFC). We found improved spatial short- and long-term memory in the radial arm maze, which was accompanied by enhanced long-term potentiation (LTP) in hippocampal CA1 region. In contrast, LTP in the PFC was unchanged when compared with wild-type controls. Changes in paired-pulse facilitation that became overt in the presence of the GABAA antagonist picrotoxin indicated a function of mGluR4 in maintaining the excitation/inhibition balance, which is of crucial importance for information processing in the brain and the deterioration of these processes in neuropsychological disorders such as autism, epilepsy and schizophrenia. © 2013 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

How the definition of acceptable antigens and epitope analysis can facilitate transplantation of highly sensitized patients with excellent long-term graft survival.

PubMed

Heidt, Sebastiaan; Haasnoot, Geert W; Claas, Frans H J

2018-05-24

Highly sensitized patients awaiting a renal transplant have a low chance of receiving an organ offer. Defining acceptable antigens and using this information for allocation purposes can vastly enhance transplantation of this subgroup of patients, which is the essence of the Eurotransplant Acceptable Mismatch program. Acceptable antigens can be determined by extensive laboratory testing, as well as on basis of human leukocyte antigen (HLA) epitope analyses. Within the Acceptable Mismatch program, there is no effect of HLA mismatches on long-term graft survival. Furthermore, patients transplanted through the Acceptable Mismatch program have similar long-term graft survival to nonsensitized patients transplanted through regular allocation. Although HLA epitope analysis is already being used for defining acceptable HLA antigens for highly sensitized patients in the Acceptable Mismatch program, increasing knowledge on HLA antibody - epitope interactions will pave the way toward the definition of acceptable epitopes for highly sensitized patients in the future. Allocation based on acceptable antigens can facilitate transplantation of highly sensitized patients with excellent long-term graft survival.

Low-carbohydrate diets: what are the potential short- and long-term health implications?

PubMed

Bilsborough, Shane A; Crowe, Timothy C

2003-01-01

Low-carbohydrate diets for weight loss are receiving a lot of attention of late. Reasons for this interest include a plethora of low-carbohydrate diet books, the over-sensationalism of these diets in the media and by celebrities, and the promotion of these diets in fitness centres and health clubs. The re-emergence of low-carbohydrate diets into the spotlight has lead many people in the general public to question whether carbohydrates are inherently 'bad' and should be limited in the diet. Although low-carbohydrate diets were popular in the 1970s they have resurged again yet little scientific fact into the true nature of how these diets work or, more importantly, any potential for serious long-term health risks in adopting this dieting practice appear to have reached the mainstream literature. Evidence abounds that low-carbohydrate diets present no significant advantage over more traditional energy-restricted, nutritionally balanced diets both in terms of weight loss and weight maintenance. Studies examining the efficacy of using low-carbohydrate diets for long-term weight loss are few in number, however few positive benefits exist to promote the adoption of carbohydrate restriction as a realistic, and more importantly, safe means of dieting. While short-term carbohydrate restriction over a period of a week can result in a significant loss of weight (albeit mostly from water and glycogen stores), of serious concern is what potential exists for the following of this type of eating plan for longer periods of months to years. Complications such as heart arrhythmias, cardiac contractile function impairment, sudden death, osteoporosis, kidney damage, increased cancer risk, impairment of physical activity and lipid abnormalities can all be linked to long-term restriction of carbohydrates in the diet. The need to further explore and communicate the untoward side-effects of low-carbohydrate diets should be an important public health message from nutrition professionals.

Long-Term Exposure to American and European Movies and Television Series Facilitates Caucasian Face Perception in Young Chinese Watchers.

PubMed

Wang, Yamin; Zhou, Lu

2016-10-01

Most young Chinese people now learn about Caucasian individuals via media, especially American and European movies and television series (AEMT). The current study aimed to explore whether long-term exposure to AEMT facilitates Caucasian face perception in young Chinese watchers. Before the experiment, we created Chinese, Caucasian, and generic average faces (generic average face was created from both Chinese and Caucasian faces) and tested participants' ability to identify them. In the experiment, we asked AEMT watchers and Chinese movie and television series (CMT) watchers to complete a facial norm detection task. This task was developed recently to detect norms used in facial perception. The results indicated that AEMT watchers coded Caucasian faces relative to a Caucasian face norm better than they did to a generic face norm, whereas no such difference was found among CMT watchers. All watchers coded Chinese faces by referencing a Chinese norm better than they did relative to a generic norm. The results suggested that long-term exposure to AEMT has the same effect as daily other-race face contact in shaping facial perception. © The Author(s) 2016.

Long-term variability of the thunderstorm and hail potential in Europe

NASA Astrophysics Data System (ADS)

Mohr, Susanna; Kunz, Michael; Speidel, Johannes; Piper, David

2016-04-01

Severe thunderstorms and associated hazardous weather events such as hail frequently cause considerable damage to buildings, crops, and automobiles, resulting in large monetary costs in many parts of Europe and the world. To relate single extreme hail events to the historic context and to estimate their return periods and possible trends related to climate change, long-term statistics of hail events are required. Due to the local-scale nature of hail and a lack of suitable observation systems, however, hailstorms are not captured reliably and comprehensively for a long period of time. In view of this fact, different proxies (indirect climate data) obtained from sounding stations and regional climate models can be used to infer the probability and intensity of thunderstorms or hailstorms. In contrast to direct observational data, such proxies are available homogeneously over a long time period. The aim of the study is to investigate the potential for severe thunderstorms and their changes over past decades. Statistical analyses of sounding data show that the convective potential over the past 20 - 30 years has significantly increased over large parts of Central Europe, making severe thunderstorms more likely. A similar picture results from analyses of weather types that are most likely associated with damaging hailstorms. These weather patterns have increased, even if only slightly but nevertheless statistically significantly, in the time period from 1971 to 2000. To improve the diagnostics of hail events in regional climate models, a logistic hail model has been developed by means of a multivariate analysis method. The model is based on a combination of appropriate hail-relevant meteorological parameters. The output of the model is a new index that estimates the potential of the atmosphere for hailstorm development, referred to as potential hail index (PHI). Applied to a high-resolved reanalysis run for Europe driven by NCEP/NCAR1, long-term changes of the PHI for

Long-Term Visuo-Gustatory Appetitive and Aversive Conditioning Potentiate Human Visual Evoked Potentials

PubMed Central

Christoffersen, Gert R. J.; Laugesen, Jakob L.; Møller, Per; Bredie, Wender L. P.; Schachtman, Todd R.; Liljendahl, Christina; Viemose, Ida

2017-01-01

Human recognition of foods and beverages are often based on visual cues associated with flavors. The dynamics of neurophysiological plasticity related to acquisition of such long-term associations has only recently become the target of investigation. In the present work, the effects of appetitive and aversive visuo-gustatory conditioning were studied with high density EEG-recordings focusing on late components in the visual evoked potentials (VEPs), specifically the N2-P3 waves. Unfamiliar images were paired with either a pleasant or an unpleasant juice and VEPs evoked by the images were compared before and 1 day after the pairings. In electrodes located over posterior visual cortex areas, the following changes were observed after conditioning: the amplitude from the N2-peak to the P3-peak increased and the N2 peak delay was reduced. The percentage increase of N2-to-P3 amplitudes was asymmetrically distributed over the posterior hemispheres despite the fact that the images were bilaterally symmetrical across the two visual hemifields. The percentage increases of N2-to-P3 amplitudes in each experimental subject correlated with the subject’s evaluation of positive or negative hedonic valences of the two juices. The results from 118 scalp electrodes gave surface maps of theta power distributions showing increased power over posterior visual areas after the pairings. Source current distributions calculated from swLORETA revealed that visual evoked currents rose as a result of conditioning in five cortical regions—from primary visual areas and into the inferior temporal gyrus (ITG). These learning-induced changes were seen after both appetitive and aversive training while a sham trained control group showed no changes. It is concluded that long-term visuo-gustatory conditioning potentiated the N2-P3 complex, and it is suggested that the changes are regulated by the perceived hedonic valence of the US. PMID:28983243

Short-term plasticity and long-term potentiation mimicked in single inorganic synapses

NASA Astrophysics Data System (ADS)

Ohno, Takeo; Hasegawa, Tsuyoshi; Tsuruoka, Tohru; Terabe, Kazuya; Gimzewski, James K.; Aono, Masakazu

2011-08-01

Memory is believed to occur in the human brain as a result of two types of synaptic plasticity: short-term plasticity (STP) and long-term potentiation (LTP; refs , , , ). In neuromorphic engineering, emulation of known neural behaviour has proven to be difficult to implement in software because of the highly complex interconnected nature of thought processes. Here we report the discovery of a Ag2S inorganic synapse, which emulates the synaptic functions of both STP and LTP characteristics through the use of input pulse repetition time. The structure known as an atomic switch, operating at critical voltages, stores information as STP with a spontaneous decay of conductance level in response to intermittent input stimuli, whereas frequent stimulation results in a transition to LTP. The Ag2S inorganic synapse has interesting characteristics with analogies to an individual biological synapse, and achieves dynamic memorization in a single device without the need of external preprogramming. A psychological model related to the process of memorizing and forgetting is also demonstrated using the inorganic synapses. Our Ag2S element indicates a breakthrough in mimicking synaptic behaviour essential for the further creation of artificial neural systems that emulate characteristics of human memory.

Homolog of protein kinase Mζ maintains context aversive memory and underlying long-term facilitation in terrestrial snail Helix

PubMed Central

Balaban, Pavel M.; Roshchin, Matvey; Timoshenko, Alia Kh.; Zuzina, Alena B.; Lemak, Maria; Ierusalimsky, Victor N.; Aseyev, Nikolay A.; Malyshev, Aleksey Y.

2015-01-01

It has been shown that a variety of long-term memories in different regions of the brain and in different species are quickly erased by local inhibition of protein kinase Mζ (PKMζ), a persistently active protein kinase. Using antibodies to mammalian PKMζ, we describe in the present study the localization of immunoreactive molecules in the nervous system of the terrestrial snail Helix lucorum. Presence of a homolog of PKMζ was confirmed with transcriptomics. We have demonstrated in behavioral experiments that contextual fear memory disappeared under a blockade of PKMζ with a selective peptide blocker of PKMζ zeta inhibitory peptide (ZIP), but not with scrambled ZIP. If ZIP was combined with a “reminder” (20 min in noxious context), no impairment of the long-term contextual memory was observed. In electrophysiological experiments we investigated whether PKMζ takes part in the maintenance of long-term facilitation (LTF) in the neural circuit mediating tentacle withdrawal. LTF of excitatory synaptic inputs to premotor interneurons was induced by high-frequency nerve stimulation combined with serotonin bath applications and lasted at least 4 h. We found that bath application of 2 × 10−6 M ZIP at the 90th min after the tetanization reduced the EPSP amplitude to the non-tetanized EPSP values. Applications of the scrambled ZIP peptide at a similar time and concentration didn’t affect the EPSP amplitudes. In order to test whether effects of ZIP are specific to the synapses, we performed experiments with LTF of somatic membrane responses to local glutamate applications. It was shown earlier that serotonin application in such an “artificial synapse” condition elicits LTF of responses to glutamate. It was found that ZIP had no effect on LTF in these conditions, which may be explained by the very low concentration of PKMζ molecules in somata of these identified neurons, as evidenced by immunochemistry. Obtained results suggest that the Helix homolog of PKM�

Near-Term Actions to Address Long-Term Climate Risk

NASA Astrophysics Data System (ADS)

Lempert, R. J.

2014-12-01

Addressing climate change requires effective long-term policy making, which occurs when reflecting on potential events decades or more in the future causes policy makers to choose near-term actions different than those they would otherwise pursue. Contrary to some expectations, policy makers do sometimes make such long-term decisions, but not as commonly and successfully as climate change may require. In recent years however, the new capabilities of analytic decision support tools, combined with improved understanding of cognitive and organizational behaviors, has significantly improved the methods available for organizations to manage longer-term climate risks. In particular, these tools allow decision makers to understand what near-term actions consistently contribute to achieving both short- and long-term societal goals, even in the face of deep uncertainty regarding the long-term future. This talk will describe applications of these approaches for infrastructure, water, and flood risk management planning, as well as studies of how near-term choices about policy architectures can affect long-term greenhouse gas emission reduction pathways.

Long-term potentiation and depression after unilateral labyrinthectomy in the medial vestibular nucleus of rats.

PubMed

Pettorossi, Vito Enrico; Dutia, Mayank; Frondaroli, Adele; Dieni, Cristina; Grassi, Silvarosa

2003-01-01

We previously demonstrated in rat brainstem slices that high-frequency stimulation (HFS) of the vestibular afferents induces long-term potentiation (LTP) in the ventral part (Vp) of the medial vestibular nucleus (MVN) and long-term depression (LTD) in the dorsal part (Dp). Both LTP and LTD depend on N-methyl-D-aspartate receptor activation, which increases synaptic efficacy; however, in the Dp, LTP reverses to LTD because of the activation of gamma-aminobutyric acid-ergic neurons. Here we show that the probability of inducing long-term effects in the MVN of rat brainstem slices is altered after unilateral labyrinthectomy (UL). In fact, LTP occurs less frequently in the ventral contra-lesional side compared with sham-operated rats. In the dorsal ipsi-lesional side, LTD is reduced and LTP enhanced, while the opposite occurs in the dorsal contra-lesional side. These changes in synaptic plasticity may be useful for re-balancing the tonic discharge of the MVN of the two sides during vestibular compensation, and for enhancing the dynamic responses of the deafferented MVN neurons in the long term.

Factors affecting electronic health record adoption in long-term care facilities.

PubMed

Cherry, Barbara; Carter, Michael; Owen, Donna; Lockhart, Carol

2008-01-01

Electronic health records (EHRs) hold the potential to significantly improve the quality of care in long-term care (LTC) facilities, yet limited research has been done on how facilities decide to adopt these records. This study was conducted to identify factors that hinder and facilitate EHR adoption in LTC facilities. Study participants were LTC nurses, administrators, and corporate executives. Primary barriers identified were costs, the need for training, and the culture change required to embrace technology. Primary facilitators were training programs, well-defined implementation plans, government assistance with implementation costs, evidence that EHRs will improve care outcomes, and support from state regulatory agencies. These results offer a framework of action for policy makers, LTC Leaders, and researchers.

Barriers and Facilitators in Pain Management in Long-Term Care Institutions: A Qualitative Study

ERIC Educational Resources Information Center

Fox, Patricia; Solomon, Patricia; Raina, Parminder; Jadad, Alejandro R.

2004-01-01

The purpose of this study was to identify barriers to the management of pain in long-term care institutions. Formal caregivers practising in four long-term care institutions in Hamilton, Ontario participated in eight focus groups. Participants included 6 physicians, 19 registered nurses, 8 registered practical nurses, 13 health care aides and 8…

Starting where I am: a grounded theory exploration of mindfulness as a facilitator of transition in living with a long-term condition.

PubMed

Long, Jaqui; Briggs, Michelle; Long, Andrew; Astin, Felicity

2016-10-01

To explore how practising mindfulness affects people's experiences of living with a long-term condition. Increasing evidence suggest that mindfulness meditation-based interventions benefit people with long-term conditions, particularly in terms of psychological well-being. Most evidence, however, relates to short-term outcomes and limited information exists about how people use mindfulness in the longer term and how this affects their experience of living with their condition. A qualitative study using constructivist-informed grounded theory. Using interviews, diaries and focus groups, data were collected between 2011 - 2012 from participants and/or trainers of Breathworks' mindfulness intervention. Phased recruitment enabled theoretical sampling, with data analysed concurrently using Charmaz's two-stage coding strategy. The final sample comprised 41 adults with diverse physical and/or mental health conditions. Participants reported predominantly positive experiences, almost all identifying significant changes in thinking and behaviour. A core process of 'Starting where I am' was formulated, highlighting how people became more aware and accepting of their condition and thus able to self-care more effectively. The process was encapsulated in five themes: Getting a new perspective; Feeling equipped to cope; Doing life differently; Seeing a change; and Finding mindfulness difficult. Strong resonances were identified between participants' experiences and the process of transition through which people come to terms with challenging life events. Mindfulness can be conceptualized as a facilitator of transition, enabling people to adapt to living with a long-term condition. Transition is associated with improved, self-directed self-management, which is significant to both people with long-term conditions and healthcare providers. © 2016 John Wiley & Sons Ltd.

Aspiring to physical health: The role of aspirations for physical health in facilitating long-term tobacco abstinence

PubMed Central

Niemiec, Christopher P.; Ryan, Richard M.; Deci, Edward L.; Williams, Geoffrey C.

2009-01-01

Objective To assess aspirations for physical health over 18 months. To examine whether maintained importance of aspirations for physical health mediated and/or moderated the effect of an intensive intervention on long-term tobacco abstinence. Methods Participants were randomly assigned to an intervention based on self-determination theory or to community care, and provided data at baseline and at 18 and 30 months post-randomization. Results Aspirations for physical health were better maintained over 18 months among participants in the intervention (mean change = .05), relative to community care (mean change = -.13), t = 2.66, p < .01. Maintained importance of aspirations for physical health partially mediated the treatment condition effects on seven-day point prevalence tobacco abstinence (z′ = 1.68, p < .01) and the longest number of days not smoking (z′ = 2.16, p < .01), and interacted with treatment condition to facilitate the longest number of days not smoking (β = .08, p < .05). Conclusion Maintained importance of aspirations for physical health facilitated tobacco abstinence. Practice implications Smokers may benefit from discussing aspirations for physical health within autonomy-supportive interventions. Patients may benefit from discussing aspirations during counseling about therapeutic lifestyle change and medication use. PMID:18838243

Aspiring to physical health: the role of aspirations for physical health in facilitating long-term tobacco abstinence.

PubMed

Niemiec, Christopher P; Ryan, Richard M; Deci, Edward L; Williams, Geoffrey C

2009-02-01

To assess aspirations for physical health over 18 months. To examine whether maintained importance of aspirations for physical health mediated and/or moderated the effect of an intensive intervention on long-term tobacco abstinence. Participants were randomly assigned to an intervention based on self-determination theory or to community care, and provided data at baseline and at 18 and 30 months post-randomization. Aspirations for physical health were better maintained over 18 months among participants in the intervention (mean change=.05), relative to community care (mean change=-.13), t=2.66, p<.01. Maintained importance of aspirations for physical health partially mediated the treatment condition effects on seven-day point prevalence tobacco abstinence (z'=1.68, p<.01) and the longest number of days not smoking (z'=2.16, p<.01), and interacted with treatment condition to facilitate the longest number of days not smoking (beta=.08, p<.05). Maintained importance of aspirations for physical health facilitated tobacco abstinence. Smokers may benefit from discussing aspirations for physical health within autonomy-supportive interventions. Patients may benefit from discussing aspirations during counseling about therapeutic lifestyle change and medication use.

Differences in kainate receptor involvement in hippocampal mossy fibre long-term potentiation depending on slice orientation.

PubMed

Sherwood, John L; Amici, Mascia; Dargan, Sheila L; Culley, Georgia R; Fitzjohn, Stephen M; Jane, David E; Collingridge, Graham L; Lodge, David; Bortolotto, Zuner A

2012-09-01

Long-term potentiation (LTP) is a well-established experimental model used to investigate the synaptic basis of learning and memory. LTP at mossy fibre - CA3 synapses in the hippocampus is unusual because it is normally N-methyl-d-aspartate (NMDA) receptor-independent. Instead it seems that the trigger for mossy fibre LTP involves kainate receptors (KARs). Although it is generally accepted that pre-synaptic KARs play an essential role in frequency facilitation and LTP, their subunit composition remains a matter of significant controversy. We have reported previously that both frequency facilitation and LTP can be blocked by selective antagonism of GluK1 (formerly GluR5/Glu(K5))-containing KARs, but other groups have failed to reproduce this effect. Moreover, data from receptor knockout and mRNA expression studies argue against a major role of GluK1, supporting a more central role for GluK2 (formerly GluR6/Glu(K6)). A potential reason underlying the controversy in the pharmacological experiments may reside in differences in the preparations used. Here we show differences in pharmacological sensitivity of synaptic plasticity at mossy fibre - CA3 synapses depend critically on slice orientation. In transverse slices, LTP of fEPSPs was invariably resistant to GluK1-selective antagonists whereas in parasagittal slices LTP was consistently blocked by GluK1-selective antagonists. In addition, there were pronounced differences in the magnitude of frequency facilitation and the sensitivity to the mGlu2/3 receptor agonist DCG-IV. Using anterograde labelling of granule cells we show that slices of both orientations possess intact mossy fibres and both large and small presynaptic boutons. Transverse slices have denser fibre tracts but a smaller proportion of giant mossy fibre boutons. These results further demonstrate a considerable heterogeneity in the functional properties of the mossy fibre projection. Copyright © 2012 Elsevier Ltd. All rights reserved.

Modality-specific alpha modulations facilitate long-term memory encoding in the presence of distracters.

PubMed

Jiang, Haiteng; van Gerven, Marcel A J; Jensen, Ole

2015-03-01

It has been proposed that long-term memory encoding is not only dependent on engaging task-relevant regions but also on disengaging task-irrelevant regions. In particular, oscillatory alpha activity has been shown to be involved in shaping the functional architecture of the working brain because it reflects the functional disengagement of specific regions in attention and memory tasks. We here ask if such allocation of resources by alpha oscillations generalizes to long-term memory encoding in a cross-modal setting in which we acquired the ongoing brain activity using magnetoencephalography. Participants were asked to encode pictures while ignoring simultaneously presented words and vice versa. We quantified the brain activity during rehearsal reflecting subsequent memory in the different attention conditions. The key finding was that successful long-term memory encoding is reflected by alpha power decreases in the sensory region of the to-be-attended modality and increases in the sensory region of the to-be-ignored modality to suppress distraction during rehearsal period. Our results corroborate related findings from attention studies by demonstrating that alpha activity is also important for the allocation of resources during long-term memory encoding in the presence of distracters.

Long-term environmental monitoring for assessment of change: measurement inconsistencies over time and potential solutions.

PubMed

Ellingsen, Kari E; Yoccoz, Nigel G; Tveraa, Torkild; Hewitt, Judi E; Thrush, Simon F

2017-10-30

The importance of long-term environmental monitoring and research for detecting and understanding changes in ecosystems and human impacts on natural systems is widely acknowledged. Over the last decades, a number of critical components for successful long-term monitoring have been identified. One basic component is quality assurance/quality control protocols to ensure consistency and comparability of data. In Norway, the authorities require environmental monitoring of the impacts of the offshore petroleum industry on the Norwegian continental shelf, and in 1996, a large-scale regional environmental monitoring program was established. As a case study, we used a sub-set of data from this monitoring to explore concepts regarding best practices for long-term environmental monitoring. Specifically, we examined data from physical and chemical sediment samples and benthic macroinvertebrate assemblages from 11 stations from six sampling occasions during the period 1996-2011. Despite the established quality assessment and quality control protocols for this monitoring program, we identified several data challenges, such as missing values and outliers, discrepancies in variable and station names, changes in procedures without calibration, and different taxonomic resolution. Furthermore, we show that the use of different laboratories over time makes it difficult to draw conclusions with regard to some of the observed changes. We offer recommendations to facilitate comparison of data over time. We also present a new procedure to handle different taxonomic resolution, so valuable historical data is not discarded. These topics have a broader relevance and application than for our case study.

Opposing Actions of Chronic[Deta][superscript 9] Tetrahydrocannabinol and Cannabinoid Antagonists on Hippocampal Long-Term Potentiation

ERIC Educational Resources Information Center

Hoffman, Alexander F.; Oz, Murat; Yang, Ruiqin; Lichtman, Aron H.; Lupica, Carl R.

2007-01-01

Memory deficits produced by marijuana arise partly via interaction of the psychoactive component, [Deta][superscript 9]-tetrahydrocannabinol ([Deta][superscript 9]-THC), with cannabinoid receptors in the hippocampus. Although cannabinoids acutely reduce glutamate release and block hippocampal long-term potentiation (LTP), a potential substrate for…

Restoration of long-term potentiation in middle-aged hippocampus after induction of brain-derived neurotrophic factor.

PubMed

Rex, Christopher S; Lauterborn, Julie C; Lin, Ching-Yi; Kramár, Eniko A; Rogers, Gary A; Gall, Christine M; Lynch, Gary

2006-08-01

Restoration of neuronal viability and synaptic plasticity through increased trophic support is widely regarded as a potential therapy for the cognitive declines that characterize aging. Previous studies have shown that in the hippocampal CA1 basal dendritic field deficits in the stabilization of long-term potentiation (LTP) are evident by middle age. The present study tested whether increasing endogenous brain-derived neurotrophic factor (BDNF) could reverse this age-related change. We report here that in middle-aged (8- to 10-mo-old) rats, in vivo treatments with a positive AMPA-type glutamate receptor modulator both increase BDNF protein levels in the cortical telencephalon and restore stabilization of basal dendritic LTP as assessed in acute hippocampal slices 18 h after the last drug treatment. These effects were not attributed to enhanced synaptic transmission or to facilitation of burst responses used to induce LTP. Increasing extracellular levels of BDNF by exogenous application to slices of middle-aged rats was also sufficient to rescue the stabilization of basal dendritic LTP. Finally, otherwise stable LTP in ampakine-treated middle-aged rats can be eliminated by infusion of the extracellular BDNF scavenger TrkB-Fc. Together these results indicate that increases in endogenous BDNF signaling can offset deficits in the postinduction processes that stabilize LTP.

Intelligent power wheelchair use in long-term care: potential users' experiences and perceptions.

PubMed

Rushton, Paula W; Mortenson, Ben W; Viswanathan, Pooja; Wang, Rosalie H; Miller, William C; Hurd Clarke, Laura

2017-10-01

Long-term care (LTC) residents with cognitive impairments frequently experience limited mobility and participation in preferred activities. Although a power wheelchair could mitigate some of these mobility and participation challenges, this technology is often not prescribed for this population due to safety concerns. An intelligent power wheelchair (IPW) system represents a potential intervention that could help to overcome these concerns. The purpose of this study was to explore a) how residents experienced an IPW that used three different modes of control and b) what perceived effect the IPW would have on their daily lives. We interviewed 10 LTC residents with mild or moderate cognitive impairment twice, once before and once after testing the IPW. Interviews were conducted using a semi-structured interview guide, audio recorded and transcribed verbatim for thematic analyses. Our analyses identified three overarching themes: (1) the difference an IPW would make, (2) the potential impact of the IPW on others and (3) IPW-related concerns. Findings from this study confirm the need for and potential benefits of IPW use in LTC. Future studies will involve testing IPW improvements based on feedback and insights from this study. Implications for rehabilitation Intelligent power wheelchairs may enhance participation and improve safety and feelings of well-being for long-term care residents with cognitive impairments. Intelligent power wheelchairs could potentially have an equally positive impact on facility staff, other residents, and family and friends by decreasing workload and increasing safety.

Circadian Regulation of Hippocampal Long-Term Potentiation

PubMed Central

Chaudhury, Dipesh; Wang, Louisa M.; Colwell, Christopher S.

2008-01-01

The goal of this study is to investigate the possible circadian regulation of hippocampal excitability and long-term potentiation (LTP) measured by stimulating the Schaffer collaterals (SC) and recording the field excitatory postsynaptic potential (fEPSP) from the CA1 dendritic layer or the population spike (PS) from the soma in brain slices of C3H and C57 mice. These 2 strains of mice were of interest because the C3H mice secrete melatonin rhythmically while the C57 mice do not. The authors found that the magnitude of the enhancement of the PS was significantly greater in LTP recorded from night slices compared to day slices of both C3H and C57 mice. They also found significant diurnal variation in the decay of LTP measured with fEPSPs, with the decay slower during the night in both strains of mice. There was evidence for a diurnal rhythm in the input/output function of pyramidal neurons measured at the soma in C57 but not C3H mice. Furthermore, LTP in the PS, measured in slices prepared during the day but recorded during the night, had a profile remarkably similar to the night group. Finally, PS recordings were carried out in slices from C3H mice maintained in constant darkness prior to experimentation. Again, the authors found that the magnitude of the enhancement of the PS was significantly greater in LTP recorded from subjective night slices compared to subjective day slices. These results provide the 1st evidence that an endogenous circadian oscillator modulates synaptic plasticity in the hippocampus. PMID:15851529

Hyaluronan preserves the proliferation and differentiation potentials of long-term cultured murine adipose-derived stromal cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, P.-Y.; Huang, Lynn L.H.; Hsieh, H.-J.

2007-08-17

For long-term culture, murine adipose-derived stromal cells (mADSCs) at latter passages demonstrated a marked decline in proliferative activity, exhibited senescent morphology and reduced differentiation potentials, particularly osteogenesis. To extend the lifespan of mADSCs, two culture conditions containing hyaluronan (HA) was compared in our study, one as a culture medium supplement (SHA), and the other where HA was pre-coated on culture surface (CHA). mADSCs cultivated with SHA exhibited a prolonged lifespan, reduced cellular senescence, and enhanced osteogenic potential compared to regular culture condition (control). Upon CHA treatment, mADSCs tended to form cell aggregates with gradual growth profiles, while their differentiation activitiesmore » remained similar to SHA groups. After transferring mADSCs from CHA to control surface, they were shown to have an extended lifespan and an increase of osteogenic potential. Our results suggested that HA can be useful for preserving the proliferation and differentiation potentials of long-term cultured mADSCs.« less

Long-term data archiving

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moore, David Steven

2009-01-01

Long term data archiving has much value for chemists, not only to retain access to research and product development records, but also to enable new developments and new discoveries. There are some recent regulatory requirements (e.g., FDA 21 CFR Part 11), but good science and good business both benefit regardless. A particular example of the benefits of and need for long term data archiving is the management of data from spectroscopic laboratory instruments. The sheer amount of spectroscopic data is increasing at a scary rate, and the pressures to archive come from the expense to create the data (or recreatemore » it if it is lost) as well as its high information content. The goal of long-term data archiving is to save and organize instrument data files as well as any needed meta data (such as sample ID, LIMS information, operator, date, time, instrument conditions, sample type, excitation details, environmental parameters, etc.). This editorial explores the issues involved in long-term data archiving using the example of Raman spectral databases. There are at present several such databases, including common data format libraries and proprietary libraries. However, such databases and libraries should ultimately satisfy stringent criteria for long term data archiving, including readability for long times into the future, robustness to changes in computer hardware and operating systems, and use of public domain data formats. The latter criterion implies the data format should be platform independent and the tools to create the data format should be easily and publicly obtainable or developable. Several examples of attempts at spectral libraries exist, such as the ASTM ANDI format, and the JCAMP-DX format. On the other hand, proprietary library spectra can be exchanged and manipulated using proprietary tools. As the above examples have deficiencies according to the three long term data archiving criteria, Extensible Markup Language (XML; a product of the World Wide

Dopaminergic neurotransmission dysfunction induced by amyloid-β transforms cortical long-term potentiation into long-term depression and produces memory impairment.

PubMed

Moreno-Castilla, Perla; Rodriguez-Duran, Luis F; Guzman-Ramos, Kioko; Barcenas-Femat, Alejandro; Escobar, Martha L; Bermudez-Rattoni, Federico

2016-05-01

Alzheimer's disease (AD) is a neurodegenerative condition manifested by synaptic dysfunction and memory loss, but the mechanisms underlying synaptic failure are not entirely understood. Although dopamine is a key modulator of synaptic plasticity, dopaminergic neurotransmission dysfunction in AD has mostly been associated to noncognitive symptoms. Thus, we aimed to study the relationship between dopaminergic neurotransmission and synaptic plasticity in AD models. We used a transgenic model of AD (triple-transgenic mouse model of AD) and the administration of exogenous amyloid-β (Aβ) oligomers into wild type mice. We found that Aβ decreased cortical dopamine levels and converted in vivo long-term potentiation (LTP) into long-term depression (LTD) after high-frequency stimulation delivered at basolateral amygdaloid nucleus-insular cortex projection, which led to impaired recognition memory. Remarkably, increasing cortical dopamine and norepinephrine levels rescued both high-frequency stimulation -induced LTP and memory, whereas depletion of catecholaminergic levels mimicked the Aβ-induced shift from LTP to LTD. Our results suggest that Aβ-induced dopamine depletion is a core mechanism underlying the early synaptopathy and memory alterations observed in AD models and acts by modifying the threshold for the induction of cortical LTP and/or LTD. Copyright © 2016 Elsevier Inc. All rights reserved.

Long-Term Memory Biases Auditory Spatial Attention

ERIC Educational Resources Information Center

Zimmermann, Jacqueline F.; Moscovitch, Morris; Alain, Claude

2017-01-01

Long-term memory (LTM) has been shown to bias attention to a previously learned visual target location. Here, we examined whether memory-predicted spatial location can facilitate the detection of a faint pure tone target embedded in real world audio clips (e.g., soundtrack of a restaurant). During an initial familiarization task, participants…

The flavonoid baicalein promotes NMDA receptor-dependent long-term potentiation and enhances memory.

PubMed

Wang, Wei; Wang, Fang; Yang, Yuan-Jian; Hu, Zhuang-Li; Long, Li-Hong; Fu, Hui; Xie, Na; Chen, Jian-Guo

2011-03-01

There is growing interest in the physiological functions of flavonoids, especially in their effects on cognitive function and on neurodegenerative diseases. The aim of the current investigation was to evaluate the role of the flavonoid baicalein in long-term potentiation (LTP) in the hippocampal CA1 region and cognitive behavioural performance. Effects of baicalein on LTP in rat hippocampal slices were investigated by electrophysiological methods. Phosphorylation of Akt (at Ser(473)), the extracellular signal-regulated kinase (ERK1/2) and the transcription factor cAMP response element-binding protein (CREB) (at Ser(133)) were analysed by Western blot. Fear conditioning was used to determine whether baicalein could improve learning and memory in rats. Baicalein enhanced the N-methyl-d-aspartate glutamate receptor-dependent LTP in a bell-shaped concentration-dependent manner. Addition of the lipoxygenase metabolites 12(S)-HETE and 12(S)-HPETE did not reverse these effects of baicalein. Baicalein treatment enhanced phosphorylation of Akt during induction of LTP with the same bell-shaped dose-response curve. LTP potentiation induced by baicalein was blocked by inhibitors of phosphoinositide 3-kinase. CREB phosphorylation was also increased in the CA1 region of baicalein-treated slices. Baicalein-treated rats performed significantly better than controls in a hippocampus-dependent contextual fear conditioning task. Furthermore, baicalein treatment selectively increased the phosphorylation of Akt and CREB in the CA1 region of hippocampus, but not in the prefrontal cortex, after fear conditioning training. Our results demonstrate that the flavonoid baicalein can facilitate memory, and therefore it might be useful in the treatment of patients with memory disorders. © 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society.

Delegation in Long-term Care: Scope of practice or job description?

PubMed

Corazzini, Kirsten N; Anderson, Ruth A; Rapp, Carla Gene; Mueller, Christine; McConnell, Eleanor S; Lekan, Deborah

2010-05-31

This study is a qualitative, descriptive study of how registered nurses (RNs) (N=33) in leadership roles in institutionalized long-term care settings delegate care, including their strategies and processes for delegating care, and their perceptions of barriers to effective delegation and potential benefits of delegation. Findings indicate two key approaches to delegation, including the "follow the job description" approach, emphasizing adherence to facility-level roles and job descriptions, and the "consider the scope of practice" approach, emphasizing consideration of multiple aspects of scope of practice and licensure, and the context of care. While the former resulted in more clarity and certainty for the RN, the latter facilitated a focus on quality of resident care outcomes as linked to the delegation process. Barriers to effective delegation were comparable among RNs using either approach to delegation, and almost all RNs could describe benefits of delegation for long-term care.

Long-term antibiotic delivery by chitosan-based composite coatings with bone regenerative potential

NASA Astrophysics Data System (ADS)

Ordikhani, F.; Simchi, A.

2014-10-01

Composite coatings with bone-bioactivity and drug-eluting capacity are considered as promising materials for titanium bone implants. In this work, drug-eluting chitosan-bioactive glass coatings were fabricated by a single-step electrophoretic deposition technique. Drug-loading and -releasing capacity of the composite coatings were carried out using the vancomycin antibiotic. Uniform coatings with a thickness of ∼55 μm containing 23.7 wt% bioactive glass particles and various amounts of the antibiotic (380-630 μg/cm2) were produced. The coatings were bioactive in terms of apatite-forming ability in simulated body fluid and showed favorable cell adhesion and growth. In vitro biological tests also indicated that the composite coatings had better cellular affinity than pristine chitosan coatings. The in vitro elution kinetics of the composite coating revealed an initial burst release of around 40% of the drug within the first elution step of 1 h and following by a continuous eluting over 4 weeks, revealing long-term drug-delivering potential. Antibacterial tests using survival assay against Gram-positive Staphylococcus aureus bacteria determined the effect of vancomycin release on reduction of infection risk. Almost no bacteria were survived on the coatings prepared from the EPD suspension containing ≥0.5 g/l vancomycin. The developed chitosan-based composite coatings with bone bioactivity and long-term drug-delivery ability may be potentially useful for metallic implants to reduce infection risk.

An overview of potential labor-saving and quality-improving innovations in long-term care for older people.

PubMed

Thoma-Lürken, Theresa; Bleijlevens, Michel H C; Lexis, Monique A S; Hamers, Jan P H; de Witte, Luc P

2015-06-01

Increasing demands in long-term care for older people and a decrease in workforce availability can be expected in the future. These developments challenge the sustainability and quality of long-term care for older people. To address these challenges, long-term care organizations are forced to innovate. The aim of this study is to provide an overview of potential labor-saving and quality-improving innovations long-term care organizations are working on and to assess the self-reported extent of effectiveness. This is a descriptive cross-sectional study. In total, 32 long-term care organizations in the region of Limburg in The Netherlands were invited to participate in the study. The inventory was performed by means of semistructured interviews with chief executive officers, managers, and staff members of the long-term care organizations. Based on the interview data, all innovations were described in a standardized form and subsequently checked by the participants. All innovations were clustered into product, process, organizational, and marketing innovations. In total, 26 long-term care organizations delivering home and/or institutional long-term care for older people participated in the study. Overall, 228 innovations were identified; some innovations were described in a similar way by different organizations. The majority of innovations were product innovations (n = 96), followed by organizational innovations (n = 75), and process innovations (n = 42). In addition to the main types, 15 other innovations incorporating characteristics of different types of innovations were detected. Little evidence about the effectiveness of the innovations was reported by the organizations. This study shows that a large number and a broad variety of innovations have been implemented or are currently being developed in long-term care organizations for older people. However, according to the organizations, there is relatively little (scientific) evidence confirming the effectiveness

Metabotropic glutamate receptors are required for the induction of long-term potentiation

NASA Technical Reports Server (NTRS)

Zheng, F.; Gallagher, J. P.

1992-01-01

Recent observations have led to the suggestion that the metabotropic glutamate receptor may play a role in the induction or maintenance of long-term potentiation (LTP). However, experimental evidence supporting a role for this receptor in the induction of LTP is still inconclusive and controversial. Here we report that, in rat dorsolateral septal nucleus (DLSN) neurons, which have the highest density of metabotropic receptors and show functional responses, the induction of LTP is not blocked by the NMDA receptor antagonist 2-amino-5-phosphonovalerate, but is blocked by two putative metabotropic glutamate receptor antagonists, L-2-amino-3-phosphonopropionic acid and L-2-amino-4-phosphonobutyrate. Furthermore, superfusion of (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid, a selective metabotropic glutamate agonist, resulted in a long-lasting potentiation of synaptic transmission similar to that induced by tetanic stimuli. Our results demonstrated that activation of postsynaptic metabotropic receptors is both necessary and sufficient for the induction of LTP in the DLSN, and we suggest that such a mechanism may be important at other CNS synapses.

Chronic Intermittent Hypoxia Blunts the Expression of Ventilatory Long Term Facilitation in Sleeping Rats.

PubMed

Edge, Deirdre; O'Halloran, Ken D

2015-01-01

We have previously reported that chronic intermittent hypoxia (CIH), a central feature of human sleep-disordered breathing, causes respiratory instability in sleeping rats (Edge D, Bradford A, O'halloran KD. Adv Exp Med Biol 758:359-363, 2012). Long term facilitation (LTF) of respiratory motor outputs following exposure to episodic, but not sustained, hypoxia has been described. We hypothesized that CIH would enhance ventilatory LTF during sleep. We examined the effects of 3 and 7 days of CIH exposure on the expression of ventilatory LTF in sleeping rats. Adult male Wistar rats were exposed to 20 cycles of normoxia and hypoxia (5 % O(2) at nadir; SaO(2) ~ 80 %) per hour, 8 h per day for 3 or 7 consecutive days (CIH, N = 7 per group). Corresponding sham groups (N = 7 per group) were subjected to alternating cycles of air under identical experimental conditions in parallel. Following gas exposures, breathing during sleep was assessed in unrestrained, unanaesthetized animals using the technique of whole-body plethysmography. Rats were exposed to room air (baseline) and then to an acute IH (AIH) protocol consisting of alternating periods of normoxia (7 min) and hypoxia (FiO(2) 0.1, 5 min) for 10 cycles. Breathing was monitored during the AIH exposure and for 1 h in normoxia following AIH exposure. Baseline ventilation was elevated after 3 but not 7 days of CIH exposure. The hypoxic ventilatory response was equivalent in sham and CIH animals after 3 days but ventilatory responses to repeated hypoxic challenges were significantly blunted following 7 days of CIH. Minute ventilation was significantly elevated following AIH exposure compared to baseline in sham but not in CIH exposed animals. LTF, determined as the % increase in minute ventilation from baseline following AIH exposure, was significantly blunted in CIH exposed rats. In summary, CIH leads to impaired ventilatory responsiveness to AIH. Moreover, CIH blunts ventilatory LTF. The physiological

Anti-Hebbian long-term potentiation in the hippocampal feedback inhibitory circuit.

PubMed

Lamsa, Karri P; Heeroma, Joost H; Somogyi, Peter; Rusakov, Dmitri A; Kullmann, Dimitri M

2007-03-02

Long-term potentiation (LTP), which approximates Hebb's postulate of associative learning, typically requires depolarization-dependent glutamate receptors of the NMDA (N-methyl-D-aspartate) subtype. However, in some neurons, LTP depends instead on calcium-permeable AMPA-type receptors. This is paradoxical because intracellular polyamines block such receptors during depolarization. We report that LTP at synapses on hippocampal interneurons mediating feedback inhibition is "anti-Hebbian":Itis induced by presynaptic activity but prevented by postsynaptic depolarization. Anti-Hebbian LTP may occur in interneurons that are silent during periods of intense pyramidal cell firing, such as sharp waves, and lead to their altered activation during theta activity.

A Critical Role for the Nucleus Reuniens in Long-Term, But Not Short-Term Associative Recognition Memory Formation.

PubMed

Barker, Gareth R I; Warburton, Elizabeth Clea

2018-03-28

Recognition memory for single items requires the perirhinal cortex (PRH), whereas recognition of an item and its associated location requires a functional interaction among the PRH, hippocampus (HPC), and medial prefrontal cortex (mPFC). Although the precise mechanisms through which these interactions are effected are unknown, the nucleus reuniens (NRe) has bidirectional connections with each regions and thus may play a role in recognition memory. Here we investigated, in male rats, whether specific manipulations of NRe function affected performance of recognition memory for single items, object location, or object-in-place associations. Permanent lesions in the NRe significantly impaired long-term, but not short-term, object-in-place associative recognition memory, whereas single item recognition memory and object location memory were unaffected. Temporary inactivation of the NRe during distinct phases of the object-in-place task revealed its importance in both the encoding and retrieval stages of long-term associative recognition memory. Infusions of specific receptor antagonists showed that encoding was dependent on muscarinic and nicotinic cholinergic neurotransmission, whereas NMDA receptor neurotransmission was not required. Finally, we found that long-term object-in-place memory required protein synthesis within the NRe. These data reveal a specific role for the NRe in long-term associative recognition memory through its interactions with the HPC and mPFC, but not the PRH. The delay-dependent involvement of the NRe suggests that it is not a simple relay station between brain regions, but, rather, during high mnemonic demand, facilitates interactions between the mPFC and HPC, a process that requires both cholinergic neurotransmission and protein synthesis. SIGNIFICANCE STATEMENT Recognizing an object and its associated location, which is fundamental to our everyday memory, requires specific hippocampal-cortical interactions, potentially facilitated by the

SNAP-25 in hippocampal CA3 region is required for long-term memory formation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hou Qiuling; Gao Xiang; Lu Qi

SNAP-25 is a synaptosomal protein of 25 kDa, a key component of synaptic vesicle-docking/fusion machinery, and plays a critical role in exocytosis and neurotransmitter release. We previously reported that SNAP-25 in the hippocampal CA1 region is involved in consolidation of contextual fear memory and water-maze spatial memory (Hou et al. European J Neuroscience, 20: 1593-1603, 2004). SNAP-25 is expressed not only in the CA1 region, but also in the CA3 region, and the SNAP-25 mRNA level in the CA3 region is higher than in the CA1 region. Here, we provide evidence that SNAP-25 in the CA3 region is also involvedmore » in learning/memory. Intra-CA3 infusion of SNAP-25 antisense oligonucleotide impaired both long-term contextual fear memory and water-maze spatial memory, with short-term memory intact. Furthermore, the SNAP-25 antisense oligonucleotide suppressed the long-term potentiation (LTP) of field excitatory post-synaptic potential (fEPSP) in the mossy-fiber pathway (DG-CA3 pathway), with no effect on paired-pulse facilitation of the fEPSP. These results are consistent with the notion that SNAP-25 in the hippocampal CA3 region is required for long-term memory formation.« less

Maternity Leave and Mothers' Long-Term Sickness Absence: Evidence From West Germany.

PubMed

Guertzgen, Nicole; Hank, Karsten

2018-04-01

Exploiting unique German administrative data, we estimate the association between an expansion in maternity leave duration from two to six months in 1979 and mothers' postbirth long-term sickness absence over a period of three decades after childbirth. Adopting a difference-in-difference approach, we first assess the reform's labor market effects and, subsequently, prebirth and postbirth maternal long-term sickness absence, accounting for the potential role of the reform in mothers' selection into employment. Consistent with previous research, our estimates show that the leave extension caused mothers to significantly delay their return to work within the first year after childbirth. We then provide difference-in-difference estimates for the number and length of spells of long-term sickness absence among returned mothers. Our findings suggest that among those returned, mothers subject to the leave extension exhibit a higher incidence of long-term sickness absence compared with mothers who gave birth before the reform. This also holds true after we control for observable differences in prebirth illness histories. At the same time, we find no pronounced effects on mothers' medium-run labor market attachment following the short-run delay in return to work, which might rationalize a negative causal health effect. Breaking down the results by mothers' prebirth health status suggests that the higher incidence of long-term sickness absence among mothers subject to the reform may be explained by the fact that the reform facilitated the reentry of a negative health selection into the labor market.

Hypoxia-Induced neonatal seizures diminish silent synapses and long-term potentiation in hippocampal CA1 neurons

PubMed Central

Zhou, Chengwen; Bell, Jocelyn J. Lippman; Sun, Hongyu; Jensen, Frances E.

2012-01-01

Neonatal seizures can lead to epilepsy and long-term cognitive deficits in adulthood. Using a rodent model of the most common form of human neonatal seizures, hypoxia-induced seizures (HS), we aimed to determine whether these seizures modify long-term potentiation (LTP) and “silent” N-methyl-D-aspartate receptor (NMDAR)-only synapses in hippocampal CA1. At 48-72 hours (hrs) post-HS, electrophysiology and immunofluorescent confocal microscopy revealed a significant decrease in the incidence of silent synapses, and an increase in amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) at the synapses. Coincident with this decrease in silent synapses, there was an attenuation of LTP elicited by either tetanic stimulation of Schaffer collaterals or a pairing protocol, and persistent attenuation of LTP in slices removed in later adulthood after P10 HS. Furthermore, post-seizure treatment in vivo with the AMPAR antagonist 2,3-dihydroxy-6-nitro-7-sulfonyl-benzo[f]quinoxaline (NBQX) protected against the HS-induced depletion of silent synapses and preserved LTP. Thus, this study demonstrates a novel mechanism by which early-life seizures could impair synaptic plasticity, suggesting a potential target for therapeutic strategies to prevent long-term cognitive deficits. PMID:22171027

Delegation in Long-term Care: Scope of practice or job description?

PubMed Central

Corazzini, Kirsten N.; Anderson, Ruth A.; Rapp, Carla Gene; Mueller, Christine; McConnell, Eleanor S.; Lekan, Deborah

2010-01-01

This study is a qualitative, descriptive study of how registered nurses (RNs) (N=33) in leadership roles in institutionalized long-term care settings delegate care, including their strategies and processes for delegating care, and their perceptions of barriers to effective delegation and potential benefits of delegation. Findings indicate two key approaches to delegation, including the “follow the job description” approach, emphasizing adherence to facility-level roles and job descriptions, and the “consider the scope of practice” approach, emphasizing consideration of multiple aspects of scope of practice and licensure, and the context of care. While the former resulted in more clarity and certainty for the RN, the latter facilitated a focus on quality of resident care outcomes as linked to the delegation process. Barriers to effective delegation were comparable among RNs using either approach to delegation, and almost all RNs could describe benefits of delegation for long-term care. PMID:25006330

Overexpression of Protein Kinase Mζ in the Hippocampus Enhances Long-Term Potentiation and Long-Term Contextual But Not Cued Fear Memory in Rats.

PubMed

Schuette, Sven R M; Fernández-Fernández, Diego; Lamla, Thorsten; Rosenbrock, Holger; Hobson, Scott

2016-04-13

The persistently active protein kinase Mζ (PKMζ) has been found to be involved in the formation and maintenance of long-term memory. Most of the studies investigating PKMζ, however, have used either putatively unselective inhibitors or conventional knock-out animal models in which compensatory mechanisms may occur. Here, we overexpressed an active form of PKMζ in rat hippocampus, a structure highly involved in memory formation, and embedded in several neural networks. We investigated PKMζ's influence on synaptic plasticity using electrophysiological recordings of basal transmission, paired pulse facilitation, and LTP and combined this with behavioral cognitive experiments addressing formation and retention of both contextual memory during aversive conditioning and spatial memory during spontaneous exploration. We demonstrate that hippocampal slices overexpressing PKMζ show enhanced basal transmission, suggesting a potential role of PKMζ in postsynaptic AMPAR trafficking. Moreover, the PKMζ-overexpressing slices augmented LTP and this effect was not abolished by protein-synthesis blockers, indicating that PKMζ induces enhanced LTP formation in a protein-synthesis-independent manner. In addition, we found selectively enhanced long-term memory for contextual but not cued fear memory, underlining the theory of the hippocampus' involvement in the contextual aspect of aversive reinforced tasks. Memory for spatial orientation during spontaneous exploration remained unaltered, suggesting that PKMζ may not affect the neural circuits underlying spontaneous tasks that are different from aversive tasks. In this study, using an overexpression strategy as opposed to an inhibitor-based approach, we demonstrate an important modulatory role of PKMζ in synaptic plasticity and selective memory processing. Most of the literature investigating protein kinase Mζ (PKMζ) used inhibitors with selectivity that has been called into question or conventional knock-out animal

Long-term metapopulation study of the Glanville fritillary butterfly (Melitaea cinxia): survey methods, data management, and long-term population trends.

PubMed

Ojanen, Sami P; Nieminen, Marko; Meyke, Evgeniy; Pöyry, Juha; Hanski, Ilkka

2013-10-01

Long-term observational studies conducted at large (regional) spatial scales contribute to better understanding of landscape effects on population and evolutionary dynamics, including the conditions that affect long-term viability of species, but large-scale studies are expensive and logistically challenging to keep running for a long time. Here, we describe the long-term metapopulation study of the Glanville fritillary butterfly (Melitaea cinxia) that has been conducted since 1991 in a large network of 4000 habitat patches (dry meadows) within a study area of 50 by 70 km in the Åland Islands in Finland. We explain how the landscape structure has been described, including definition, delimitation, and mapping of the habitat patches; methods of field survey, including the logistics, cost, and reliability of the survey; and data management using the EarthCape biodiversity platform. We describe the long-term metapopulation dynamics of the Glanville fritillary based on the survey. There has been no long-term change in the overall size of the metapopulation, but the level of spatial synchrony and hence the amplitude of fluctuations in year-to-year metapopulation dynamics have increased over the years, possibly due to increasing frequency of exceptional weather conditions. We discuss the added value of large-scale and long-term population studies, but also emphasize the need to integrate more targeted experimental studies in the context of long-term observational studies. For instance, in the case of the Glanville fritillary project, the long-term study has produced an opportunity to sample individuals for experiments from local populations with a known demographic history. These studies have demonstrated striking differences in dispersal rate and other life-history traits of individuals from newly established local populations (the offspring of colonizers) versus individuals from old, established local populations. The long-term observational study has stimulated the

Long-term metapopulation study of the Glanville fritillary butterfly (Melitaea cinxia): survey methods, data management, and long-term population trends

PubMed Central

Ojanen, Sami P; Nieminen, Marko; Meyke, Evgeniy; Pöyry, Juha; Hanski, Ilkka

2013-01-01

Long-term observational studies conducted at large (regional) spatial scales contribute to better understanding of landscape effects on population and evolutionary dynamics, including the conditions that affect long-term viability of species, but large-scale studies are expensive and logistically challenging to keep running for a long time. Here, we describe the long-term metapopulation study of the Glanville fritillary butterfly (Melitaea cinxia) that has been conducted since 1991 in a large network of 4000 habitat patches (dry meadows) within a study area of 50 by 70 km in the Åland Islands in Finland. We explain how the landscape structure has been described, including definition, delimitation, and mapping of the habitat patches; methods of field survey, including the logistics, cost, and reliability of the survey; and data management using the EarthCape biodiversity platform. We describe the long-term metapopulation dynamics of the Glanville fritillary based on the survey. There has been no long-term change in the overall size of the metapopulation, but the level of spatial synchrony and hence the amplitude of fluctuations in year-to-year metapopulation dynamics have increased over the years, possibly due to increasing frequency of exceptional weather conditions. We discuss the added value of large-scale and long-term population studies, but also emphasize the need to integrate more targeted experimental studies in the context of long-term observational studies. For instance, in the case of the Glanville fritillary project, the long-term study has produced an opportunity to sample individuals for experiments from local populations with a known demographic history. These studies have demonstrated striking differences in dispersal rate and other life-history traits of individuals from newly established local populations (the offspring of colonizers) versus individuals from old, established local populations. The long-term observational study has stimulated the

Proteasome Inhibition Enhances the Induction and Impairs the Maintenance of Late-Phase Long-Term Potentiation

ERIC Educational Resources Information Center

Dong, Chenghai; Upadhya, Sudarshan C.; Ding, Lan; Smith, Thuy K.; Hegde, Ashok N.

2008-01-01

Protein degradation by the ubiquitin-proteasome pathway plays important roles in synaptic plasticity, but the molecular mechanisms by which proteolysis regulates synaptic strength are not well understood. We investigated the role of the proteasome in hippocampal late-phase long-term potentiation (L-LTP), a model for enduring synaptic plasticity.…

Consider long-term care as service alternative.

PubMed

Loria, L S

1987-04-01

The increasing demand for elderly care services, pressures on inpatient average length of stay and payment levels, and potential financial rewards from providing additional services, makes long-term care look attractive to hospitals. Long-term care, however, is not for every hospital. Before deciding to establish long-term care services, management should examine how the service fits within the hospital's strategic plan. The action plan below provides guidance in evaluating a decision to use hospital facilities for long-term care. Examine how long-term care services fit within the hospital's strategic plan. Study area demographics and competitors to assess the need and supply of long-term care services. Survey the medical staff, consumers and payers to determine attitudes, perceptions and interests regarding long-term care services. Develop a facility plan that identifies areas of excess capacity that can be most easily converted into long-term care with minimal effects on hospital operations. Prepare a financial feasibility analysis of the contribution margin and return on investment attributable to long-term care services. Include an impact analysis on hospital operations. Establish a management task force to develop a detailed implementation plan including assigned individual responsibilities and related timetable. Develop an effective marketing plan designed to generate increased patient market share.

Long-term potential and actual evapotranspiration of two different forests on the Atlantic Coastal Plain

Treesearch

Devendra Amatya; S. Tian; Z. Dai; Ge Sun

2016-01-01

A reliable estimate of potential evapotranspiration (PET) for a forest ecosystem is critical in ecohydrologic modeling related with water supply, vegetation dynamics, and climate change and yet is a challenging task due to its complexity. Based on long-term on-site measured hydro-climatic data and predictions from earlier validated hydrologic modeling studies...

Long-term potentiation expands information content of hippocampal dentate gyrus synapses.

PubMed

Bromer, Cailey; Bartol, Thomas M; Bowden, Jared B; Hubbard, Dusten D; Hanka, Dakota C; Gonzalez, Paola V; Kuwajima, Masaaki; Mendenhall, John M; Parker, Patrick H; Abraham, Wickliffe C; Sejnowski, Terrence J; Harris, Kristen M

2018-03-06

An approach combining signal detection theory and precise 3D reconstructions from serial section electron microscopy (3DEM) was used to investigate synaptic plasticity and information storage capacity at medial perforant path synapses in adult hippocampal dentate gyrus in vivo. Induction of long-term potentiation (LTP) markedly increased the frequencies of both small and large spines measured 30 minutes later. This bidirectional expansion resulted in heterosynaptic counterbalancing of total synaptic area per unit length of granule cell dendrite. Control hemispheres exhibited 6.5 distinct spine sizes for 2.7 bits of storage capacity while LTP resulted in 12.9 distinct spine sizes (3.7 bits). In contrast, control hippocampal CA1 synapses exhibited 4.7 bits with much greater synaptic precision than either control or potentiated dentate gyrus synapses. Thus, synaptic plasticity altered total capacity, yet hippocampal subregions differed dramatically in their synaptic information storage capacity, reflecting their diverse functions and activation histories.

Guidelines for the collection of long-term pavement performance data

DOT National Transportation Integrated Search

2006-03-01

A set of data collection guidelines has been provided for the collection of all data obtained for the Long-Term Pavement Performance (LTPP) program. These guidelines were provided to the Regional Support Contractors (RSC) to facilitate data collectio...

Effects of intrahippocampal aniracetam treatment on Y-maze avoidance learning performance and behavioral long-term potentiation in dentate gyrus in rat.

PubMed

Rao, Y; Xiao, P; Xu, S

2001-02-09

Effects of intrahippocampal treatment of aniracetam, a selective agonist for DL-alpha-amino-3-hydroxy-5-methyl-4-isoxazoleproionic acid (AMPA) receptors, on Y-maze avoidance learning task and behavioral long-term potentiation (LTP) in perforant path-dentate gyrus were studied in freely moving rats by using in vivo electrophysiology combined with behavioral tests. The results were as follows: (1) intrahippocampal treatment of aniracetam reversibly enhanced basal synaptic transmission in perforant path to dentate gyrus in a dosage dependent manner; (2) aniracetam produced improvement in Y-maze learning performance when administration occurred 5 min prior to maze learning; (3) aniracetam administration significantly facilitated behavioral LTP in dentate gyrus, while the maximal amplitude of LTP has no significant difference when compared to saline group. The present results indicate that hippocampal AMPA receptors are involved in learning and memory.

Development of a Self-Assessment Tool to Facilitate Decision-Making in Choosing a Long Term Care Administration Major

ERIC Educational Resources Information Center

Johs-Artisensi, Jennifer L.; Olson, Douglas M.; Nahm, Abraham Y.

2016-01-01

Long term care administrators need a broad base of knowledge, skills, and interests to provide leadership and be successful in managing a fiscally responsible, quality long term care organization. Researchers developed a tool to help students assess whether a long term care administration major is a compatible fit. With input from professionals in…

Prognostic Factors and Decision Tree for Long-term Survival in Metastatic Uveal Melanoma.

PubMed

Lorenzo, Daniel; Ochoa, María; Piulats, Josep Maria; Gutiérrez, Cristina; Arias, Luis; Català, Jaum; Grau, María; Peñafiel, Judith; Cobos, Estefanía; Garcia-Bru, Pere; Rubio, Marcos Javier; Padrón-Pérez, Noel; Dias, Bruno; Pera, Joan; Caminal, Josep Maria

2017-12-04

The purpose of this study was to demonstrate the existence of a bimodal survival pattern in metastatic uveal melanoma. Secondary aims were to identify the characteristics and prognostic factors associated with long-term survival and to develop a clinical decision tree. The medical records of 99 metastatic uveal melanoma patients were retrospectively reviewed. Patients were classified as either short (≤ 12 months) or long-term survivors (> 12 months) based on a graphical interpretation of the survival curve after diagnosis of the first metastatic lesion. Ophthalmic and oncological characteristics were assessed in both groups. Of the 99 patients, 62 (62.6%) were classified as short-term survivors, and 37 (37.4%) as long-term survivors. The multivariate analysis identified the following predictors of long-term survival: age ≤ 65 years (p=0.012) and unaltered serum lactate dehydrogenase levels (p=0.018); additionally, the size (smaller vs. larger) of the largest liver metastasis showed a trend towards significance (p=0.063). Based on the variables significantly associated with long-term survival, we developed a decision tree to facilitate clinical decision-making. The findings of this study demonstrate the existence of a bimodal survival pattern in patients with metastatic uveal melanoma. The presence of certain clinical characteristics at diagnosis of distant disease is associated with long-term survival. A decision tree was developed to facilitate clinical decision-making and to counsel patients about the expected course of disease.

Long-term outcomes of acute kidney injury.

PubMed

Coca, Steven G

2010-05-01

The goal of this review is to summarize the recent plethora of data that relate to long-term outcomes after acute kidney injury (AKI). Surviving patients with AKI are still at high risk for long-term adverse outcomes, even if serum creatinine returns to normal. After adjusting for potential confounders, many recent studies have demonstrated that AKI is independently associated with chronic kidney disease, end-stage renal disease, and premature death. Unfortunately, definitive evidence from randomized controlled trials demonstrating that prevention or treatment of AKI prevents long-term adverse outcomes is not yet available. AKI is clearly a prognostic marker for poor long-term outcomes, but more studies will be needed to determine whether AKI is truly causal and whether or not the risk is modifiable.

Long-Term Opioid Therapy Reconsidered

PubMed Central

Von Korff, Michael; Kolodny, Andrew; Deyo, Richard A.; Chou, Roger

2012-01-01

In the past 20 years, primary care physicians have greatly increased prescribing of long-term opioid therapy. However, the rise in opioid prescribing has outpaced the evidence regarding this practice. Increased opioid availability has been accompanied by an epidemic of opioid abuse and overdose. The rate of opioid addiction among patients receiving long-term opioid therapy remains unclear, but research suggests that opioid misuse is not rare. Recent studies report increased risks for serious adverse events, including fractures, cardiovascular events, and bowel obstruction, although further research on medical risks is needed. New data indicate that opioid-related risks may increase with dose. From a societal perspective, higher-dose regimens account for the majority of opioids dispensed, so cautious dosing may reduce both diversion potential and patient risks for adverse effects. Limiting long-term opioid therapy to patients for whom it provides decisive benefits could also reduce risks. Given the warning signs and knowledge gaps, greater caution and selectivity are needed in prescribing long-term opioid therapy. Until stronger evidence becomes available, clinicians should err on the side of caution when considering this treatment. PMID:21893626

Mechanisms of Enhanced Phrenic Long-Term Facilitation in SOD1G93A Rats

PubMed Central

Satriotomo, Irawan; Grebe, Ashley M.

2017-01-01

Amyotrophic lateral sclerosis (ALS) is a degenerative motor neuron disease, causing muscle paralysis and death from respiratory failure. Effective means to preserve/restore ventilation are necessary to increase the quality and duration of life in ALS patients. At disease end-stage in a rat ALS model (SOD1G93A), acute intermittent hypoxia (AIH) restores phrenic nerve activity to normal levels via enhanced phrenic long-term facilitation (pLTF). Mechanisms enhancing pLTF in end-stage SOD1G93A rats are not known. Moderate AIH-induced pLTF is normally elicited via cellular mechanisms that require the following: Gq-protein-coupled 5-HT2 receptor activation, new BDNF synthesis, and MEK/ERK signaling (the Q pathway). In contrast, severe AIH elicits pLTF via a distinct mechanism that requires the following: Gs-protein-coupled adenosine 2A receptor activation, new TrkB synthesis, and PI3K/Akt signaling (the S pathway). In end-stage male SOD1G93A rats and wild-type littermates, we investigated relative Q versus S pathway contributions to enhanced pLTF via intrathecal (C4) delivery of small interfering RNAs targeting BDNF or TrkB mRNA, and MEK/ERK (U0126) or PI3 kinase/Akt (PI828) inhibitors. In anesthetized, paralyzed and ventilated rats, moderate AIH-induced pLTF was abolished by siBDNF and UO126, but not siTrkB or PI828, demonstrating that enhanced pLTF occurs via the Q pathway. Although phrenic motor neuron numbers were decreased in end-stage SOD1G93A rats (∼30% survival; p < 0.001), BDNF and phosphorylated ERK expression were increased in spared phrenic motor neurons (p < 0.05), consistent with increased Q-pathway contributions to pLTF. Our results increase understanding of respiratory plasticity and its potential to preserve/restore breathing capacity in ALS. SIGNIFICANCE STATEMENT Since neuromuscular disorders, such as amyotrophic lateral sclerosis (ALS), end life via respiratory failure, the ability to harness respiratory motor plasticity to improve breathing

Narrative organisation at encoding facilitated children's long-term episodic memory.

PubMed

Wang, Qi; Bui, Van-Kim; Song, Qingfang

2015-01-01

This study examined the effect of narrative organisation at encoding on long-term episodic memory in a sample of five- to seven-year-old children (N = 113). At an initial interview, children were asked to narrate a story from a picture book. Six months later, they were interviewed again and asked to recall the story and answer a series of direct questions about the story. Children who initially encoded more information in narrative and produced more complete, complex, cohesive and coherent narratives remembered the story in greater detail and accuracy following the six-month interval, independent of age and verbal skills. The relation between narrative organisation and memory was consistent across culture and gender. These findings provide new insight into the critical role of narrative in episodic memory.

Structural and molecular remodeling of dendritic spine substructures during long-term potentiation

PubMed Central

Bosch, Miquel; Castro, Jorge; Saneyoshi, Takeo; Matsuno, Hitomi; Sur, Mriganka; Hayashi, Yasunori

2014-01-01

SUMMARY Synapses store information by long-lasting modifications of their structure and molecular composition, but the precise chronology of these changes has not been studied at single synapse resolution in real time. Here we describe the spatiotemporal reorganization of postsynaptic substructures during long-term potentiation (LTP) at individual dendritic spines. Proteins translocated to the spine in four distinct patterns through three sequential phases. In the initial phase, the actin cytoskeleton was rapidly remodeled while active cofilin was massively transported to the spine. In the stabilization phase, cofilin formed a stable complex with F-actin, was persistently retained at the spine, and consolidated spine expansion. In contrast, the postsynaptic density (PSD) was independently remodeled, as PSD scaffolding proteins did not change their amount and localization until a late protein synthesis-dependent third phase. Our findings show how and when spine substructures are remodeled during LTP and explain why synaptic plasticity rules change over time. PMID:24742465

What Legislators Need to Know about Long-Term Care Insurance.

ERIC Educational Resources Information Center

Landes, David

This booklet discusses the potential importance to states of long-term care insurance, describes general policy characteristics, and summarizes state actions to both regulate and promote long-term care insurance. It is intended as a resource for legislators and others involved in long-term care financing and public policy formulation. Long-term…

Long-Term Memory Performance in Adult ADHD.

PubMed

Skodzik, Timo; Holling, Heinz; Pedersen, Anya

2017-02-01

Memory problems are a frequently reported symptom in adult ADHD, and it is well-documented that adults with ADHD perform poorly on long-term memory tests. However, the cause of this effect is still controversial. The present meta-analysis examined underlying mechanisms that may lead to long-term memory impairments in adult ADHD. We performed separate meta-analyses of measures of memory acquisition and long-term memory using both verbal and visual memory tests. In addition, the influence of potential moderator variables was examined. Adults with ADHD performed significantly worse than controls on verbal but not on visual long-term memory and memory acquisition subtests. The long-term memory deficit was strongly statistically related to the memory acquisition deficit. In contrast, no retrieval problems were observable. Our results suggest that memory deficits in adult ADHD reflect a learning deficit induced at the stage of encoding. Implications for clinical and research settings are presented.

Retrospective attention in short-term memory has a lasting effect on long-term memory across age.

PubMed

Strunk, Jonathan; Morgan, Lauren; Reaves, Sarah; Verhaeghen, Paul; Duarte, Audrey

2018-04-13

Declines in both short- and long-term memory are typical of healthy aging. Recent findings suggest that retrodictive attentional cues ("retro-cues") that indicate the location of to-be-probed items in short-term memory (STM) have a lasting impact on long-term memory (LTM) performance in young adults. Whether older adults can also use retro-cues to facilitate both STM and LTM is unknown. Young and older adults performed a visual STM task in which spatially informative retro-cues or non-informative neutral-cues were presented during STM maintenance of real-world objects. We tested participants' memory at both STM and LTM delays for objects that were previously cued with retrodictive or neutral cues during STM order to measure the lasting impact of retrospective attention on LTM. Older adults showed reduced STM and LTM capacity compared to young adults. However, they showed similar magnitude retro-cue memory benefits as young adults at both STM and LTM delays. To the best of our knowledge, this is the first study to investigate whether retro-cues in STM facilitate the encoding of objects into LTM such that they are more likely to be subsequently retrieved by older adults. Our results support the idea that retrospective attention can be an effective means by which older adults can improve their short and long-term memory performance, even in the context of reduced memory capacity.

Long-term climate change mitigation potential with organic matter management on grasslands.

PubMed

Ryals, Rebecca; Hartman, Melannie D; Parton, William J; DeLonge, Marcia S; Silver, Whendee L

2015-03-01

Compost amendments to grasslands have been proposed as a strategy to mitigate climate change through carbon (C) sequestration, yet little research exists exploring the net mitigation potential or the long-term impacts of this strategy. We used field data and the DAYCENT biogeochemical model to investigate the climate change mitigation potential of compost amendments to grasslands in California, USA. The model was used to test ecosystem C and greenhouse gas responses to a range of compost qualities (carbon to nitrogen [C:N] ratios of 11.1, 20, or 30) and application rates (single addition of 14 Mg C/ha or 10 annual additions of 1.4 Mg C · ha(-1) · yr(-1)). The model was parameterized using site-specific weather, vegetation, and edaphic characteristics and was validated by comparing simulated soil C, nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2) fluxes, and net primary production (NPP) with three years of field data. All compost amendment scenarios led to net greenhouse gas sinks that persisted for several decades. Rates of climate change mitigation potential ranged from 130 ± 3 g to 158 ± 8 g CO2-eq · m(-2) ·yr(-1) (where "eq" stands for "equivalents") when assessed over a 10-year time period and 63 ± 2 g to 84 ± 10 g CO2- eq · m(-2) · yr(-1) over a 30-year time period. Both C storage and greenhouse gas emissions increased rapidly following amendments. Compost amendments with lower C:N led to higher C sequestration rates over time. However, these soils also experienced greater N20 fluxes. Multiple smaller compost additions resulted in similar cumulative C sequestration rates, albeit with a time lag, and lower cumulative N2O emissions. These results identify a trade-off between maximizing C sequestration and minimizing N2O emissions following amendments, and suggest that compost additions to grassland soils can have a long-term impact on C and greenhouse gas dynamics that contributes to climate change mitigation.

Conversion of short-term to long-term memory in the novel object recognition paradigm.

PubMed

Moore, Shannon J; Deshpande, Kaivalya; Stinnett, Gwen S; Seasholtz, Audrey F; Murphy, Geoffrey G

2013-10-01

It is well-known that stress can significantly impact learning; however, whether this effect facilitates or impairs the resultant memory depends on the characteristics of the stressor. Investigation of these dynamics can be confounded by the role of the stressor in motivating performance in a task. Positing a cohesive model of the effect of stress on learning and memory necessitates elucidating the consequences of stressful stimuli independently from task-specific functions. Therefore, the goal of this study was to examine the effect of manipulating a task-independent stressor (elevated light level) on short-term and long-term memory in the novel object recognition paradigm. Short-term memory was elicited in both low light and high light conditions, but long-term memory specifically required high light conditions during the acquisition phase (familiarization trial) and was independent of the light level during retrieval (test trial). Additionally, long-term memory appeared to be independent of stress-mediated glucocorticoid release, as both low and high light produced similar levels of plasma corticosterone, which further did not correlate with subsequent memory performance. Finally, both short-term and long-term memory showed no savings between repeated experiments suggesting that this novel object recognition paradigm may be useful for longitudinal studies, particularly when investigating treatments to stabilize or enhance weak memories in neurodegenerative diseases or during age-related cognitive decline. Copyright © 2013 Elsevier Inc. All rights reserved.

Conversion of short-term to long-term memory in the novel object recognition paradigm

PubMed Central

Moore, Shannon J.; Deshpande, Kaivalya; Stinnett, Gwen S.; Seasholtz, Audrey F.; Murphy, Geoffrey G.

2013-01-01

It is well-known that stress can significantly impact learning; however, whether this effect facilitates or impairs the resultant memory depends on the characteristics of the stressor. Investigation of these dynamics can be confounded by the role of the stressor in motivating performance in a task. Positing a cohesive model of the effect of stress on learning and memory necessitates elucidating the consequences of stressful stimuli independently from task-specific functions. Therefore, the goal of this study was to examine the effect of manipulating a task-independent stressor (elevated light level) on short-term and long-term memory in the novel object recognition paradigm. Short-term memory was elicited in both low light and high light conditions, but long-term memory specifically required high light conditions during the acquisition phase (familiarization trial) and was independent of the light level during retrieval (test trial). Additionally, long-term memory appeared to be independent of stress-mediated glucocorticoid release, as both low and high light produced similar levels of plasma corticosterone, which further did not correlate with subsequent memory performance. Finally, both short-term and long-term memory showed no savings between repeated experiments suggesting that this novel object recognition paradigm may be useful for longitudinal studies, particularly when investigating treatments to stabilize or enhance weak memories in neurodegenerative diseases or during age-related cognitive decline. PMID:23835143

BAF53b, a Neuron-Specific Nucleosome Remodeling Factor, Is Induced after Learning and Facilitates Long-Term Memory Consolidation.

PubMed

Yoo, Miran; Choi, Kwang-Yeon; Kim, Jieun; Kim, Mujun; Shim, Jaehoon; Choi, Jun-Hyeok; Cho, Hye-Yeon; Oh, Jung-Pyo; Kim, Hyung-Su; Kaang, Bong-Kiun; Han, Jin-Hee

2017-03-29

Although epigenetic mechanisms of gene expression regulation have recently been implicated in memory consolidation and persistence, the role of nucleosome-remodeling is largely unexplored. Recent studies show that the functional loss of BAF53b, a postmitotic neuron-specific subunit of the BAF nucleosome-remodeling complex, results in the deficit of consolidation of hippocampus-dependent memory and cocaine-associated memory in the rodent brain. However, it is unclear whether BAF53b expression is regulated during memory formation and how BAF53b regulates fear memory in the amygdala, a key brain site for fear memory encoding and storage. To address these questions, we used viral vector approaches to either decrease or increase BAF53b function specifically in the lateral amygdala of adult mice in auditory fear conditioning paradigm. Knockdown of Baf53b before training disrupted long-term memory formation with no effect on short-term memory, basal synaptic transmission, and spine structures. We observed in our qPCR analysis that BAF53b was induced in the lateral amygdala neurons at the late consolidation phase after fear conditioning. Moreover, transient BAF53b overexpression led to persistently enhanced memory formation, which was accompanied by increase in thin-type spine density. Together, our results provide the evidence that BAF53b is induced after learning, and show that such increase of BAF53b level facilitates memory consolidation likely by regulating learning-related spine structural plasticity. SIGNIFICANCE STATEMENT Recent works in the rodent brain begin to link nucleosome remodeling-dependent epigenetic mechanism to memory consolidation. Here we show that BAF53b, an epigenetic factor involved in nucleosome remodeling, is induced in the lateral amygdala neurons at the late phase of consolidation after fear conditioning. Using specific gene knockdown or overexpression approaches, we identify the critical role of BAF53b in the lateral amygdala neurons for

Phrenic long-term facilitation following intrapleural CTB-SAP-induced respiratory motor neuron death.

PubMed

Nichols, Nicole L; Craig, Taylor A; Tanner, Miles A

2017-08-16

Amyotrophic lateral sclerosis (ALS) is a devastating disease leading to progressive motor neuron degeneration and death by ventilatory failure. In a rat model of ALS (SOD1 G93A ), phrenic long-term facilitation (pLTF) following acute intermittent hypoxia (AIH) is enhanced greater than expected at disease end-stage but the mechanism is unknown. We suggest that one trigger for this enhancement is motor neuron death itself. Intrapleural injections of cholera toxin B fragment conjugated to saporin (CTB-SAP) selectively kill respiratory motor neurons and mimic motor neuron death observed in SOD1 G93A rats. This CTB-SAP model allows us to study the impact of respiratory motor neuron death on breathing without many complications attendant to ALS. Here, we tested the hypothesis that phrenic motor neuron death is sufficient to enhance pLTF. pLTF was assessed in anesthetized, paralyzed and ventilated Sprague Dawley rats 7 and 28days following bilateral intrapleural injections of: 1) CTB-SAP (25μg), or 2) un-conjugated CTB and SAP (control). CTB-SAP enhanced pLTF at 7 (CTB-SAP: 162±18%, n=8 vs. 63±3%; n=8; p<0.05), but not 28days post-injection (CTB-SAP: 64±10%, n=10 vs. 60±13; n=8; p>0.05). Thus, pLTF at 7 (not 28) days post-CTB-SAP closely resembles pLTF in end-stage ALS rats, suggesting that processes unique to the early period of motor neuron death enhance pLTF. This project increases our understanding of respiratory plasticity and its implications for breathing in motor neuron disease. Copyright © 2017 Elsevier B.V. All rights reserved.

Implicit short- and long-term memory direct our gaze in visual search.

PubMed

Kruijne, Wouter; Meeter, Martijn

2016-04-01

Visual attention is strongly affected by the past: both by recent experience and by long-term regularities in the environment that are encoded in and retrieved from memory. In visual search, intertrial repetition of targets causes speeded response times (short-term priming). Similarly, targets that are presented more often than others may facilitate search, even long after it is no longer present (long-term priming). In this study, we investigate whether such short-term priming and long-term priming depend on dissociable mechanisms. By recording eye movements while participants searched for one of two conjunction targets, we explored at what stages of visual search different forms of priming manifest. We found both long- and short- term priming effects. Long-term priming persisted long after the bias was present, and was again found even in participants who were unaware of a color bias. Short- and long-term priming affected the same stage of the task; both biased eye movements towards targets with the primed color, already starting with the first eye movement. Neither form of priming affected the response phase of a trial, but response repetition did. The results strongly suggest that both long- and short-term memory can implicitly modulate feedforward visual processing.

A single amino acid difference between the intracellular domains of amyloid precursor protein and amyloid-like precursor protein 2 enables induction of synaptic depression and block of long-term potentiation.

PubMed

Trillaud-Doppia, Emilie; Paradis-Isler, Nicolas; Boehm, Jannic

2016-07-01

Alzheimer disease (AD) is initially characterized as a disease of the synapse that affects synaptic transmission and synaptic plasticity. While amyloid-beta and tau have been traditionally implicated in causing AD, recent studies suggest that other factors, such as the intracellular domain of the amyloid-precursor protein (APP-ICD), can also play a role in the development of AD. Here, we show that the expression of APP-ICD induces synaptic depression, while the intracellular domain of its homolog amyloid-like precursor protein 2 (APLP2-ICD) does not. We are able to show that this effect by APP-ICD is due to a single alanine vs. proline difference between APP-ICD and APLP2-ICD. The alanine in APP-ICD and the proline in APLP2-ICD lie directly behind a conserved caspase cleavage site. Inhibition of caspase cleavage of APP-ICD prevents the induction of synaptic depression. Finally, we show that the expression of APP-ICD increases and facilitates long-term depression and blocks induction of long-term potentiation. The block in long-term potentiation can be overcome by mutating the aforementioned alanine in APP-ICD to the proline of APLP2. Based on our results, we propose the emergence of a new APP critical domain for the regulation of synaptic plasticity and in consequence for the development of AD. Copyright © 2016 Elsevier Inc. All rights reserved.

Mouse pancreas tissue slice culture facilitates long-term studies of exocrine and endocrine cell physiology in situ.

PubMed

Marciniak, Anja; Selck, Claudia; Friedrich, Betty; Speier, Stephan

2013-01-01

Studies on pancreatic cell physiology rely on the investigation of exocrine and endocrine cells in vitro. Particularly, in the case of the exocrine tissue these studies have suffered from a reduced functional viability of acinar cells in culture. As a result not only investigations on dispersed acinar cells and isolated acini were limited in their potential, but also prolonged studies on pancreatic exocrine and endocrine cells in an intact pancreatic tissue environment were unfeasible. To overcome these limitations, we aimed to establish a pancreas tissue slice culture platform to allow long-term studies on exocrine and endocrine cells in the intact pancreatic environment. Mouse pancreas tissue slice morphology was assessed to determine optimal long-term culture settings for intact pancreatic tissue. Utilizing optimized culture conditions, cell specificity and function of exocrine acinar cells and endocrine beta cells were characterized over a culture period of 7 days. We found pancreas tissue slices cultured under optimized conditions to have intact tissue specific morphology for the entire culture period. Amylase positive intact acini were present at all time points of culture and acinar cells displayed a typical strong cell polarity. Amylase release from pancreas tissue slices decreased during culture, but maintained the characteristic bell-shaped dose-response curve to increasing caerulein concentrations and a ca. 4-fold maximal over basal release. Additionally, endocrine beta cell viability and function was well preserved until the end of the observation period. Our results show that the tissue slice culture platform provides unprecedented maintenance of pancreatic tissue specific morphology and function over a culture period for at least 4 days and in part even up to 1 week. This analytical advancement now allows mid -to long-term studies on the cell biology of pancreatic disorder pathogenesis and therapy in an intact surrounding in situ.

Mouse Pancreas Tissue Slice Culture Facilitates Long-Term Studies of Exocrine and Endocrine Cell Physiology in situ

PubMed Central

Marciniak, Anja; Selck, Claudia; Friedrich, Betty; Speier, Stephan

2013-01-01

Studies on pancreatic cell physiology rely on the investigation of exocrine and endocrine cells in vitro. Particularly, in the case of the exocrine tissue these studies have suffered from a reduced functional viability of acinar cells in culture. As a result not only investigations on dispersed acinar cells and isolated acini were limited in their potential, but also prolonged studies on pancreatic exocrine and endocrine cells in an intact pancreatic tissue environment were unfeasible. To overcome these limitations, we aimed to establish a pancreas tissue slice culture platform to allow long-term studies on exocrine and endocrine cells in the intact pancreatic environment. Mouse pancreas tissue slice morphology was assessed to determine optimal long-term culture settings for intact pancreatic tissue. Utilizing optimized culture conditions, cell specificity and function of exocrine acinar cells and endocrine beta cells were characterized over a culture period of 7 days. We found pancreas tissue slices cultured under optimized conditions to have intact tissue specific morphology for the entire culture period. Amylase positive intact acini were present at all time points of culture and acinar cells displayed a typical strong cell polarity. Amylase release from pancreas tissue slices decreased during culture, but maintained the characteristic bell-shaped dose-response curve to increasing caerulein concentrations and a ca. 4-fold maximal over basal release. Additionally, endocrine beta cell viability and function was well preserved until the end of the observation period. Our results show that the tissue slice culture platform provides unprecedented maintenance of pancreatic tissue specific morphology and function over a culture period for at least 4 days and in part even up to 1 week. This analytical advancement now allows mid -to long-term studies on the cell biology of pancreatic disorder pathogenesis and therapy in an intact surrounding in situ. PMID:24223842

Nicotine Uses Neuron-Glia Communication to Enhance Hippocampal Synaptic Transmission and Long-term Memory

PubMed Central

López-Hidalgo, Mónica; Salgado-Puga, Karla; Alvarado-Martínez, Reynaldo; Medina, Andrea Cristina; Prado-Alcalá, Roberto A.; García-Colunga, Jesús

2012-01-01

Nicotine enhances synaptic transmission and facilitates long-term memory. Now it is known that bi-directional glia-neuron interactions play important roles in the physiology of the brain. However, the involvement of glial cells in the effects of nicotine has not been considered until now. In particular, the gliotransmitter D-serine, an endogenous co-agonist of NMDA receptors, enables different types of synaptic plasticity and memory in the hippocampus. Here, we report that hippocampal long-term synaptic plasticity induced by nicotine was annulled by an enzyme that degrades endogenous D-serine, or by an NMDA receptor antagonist that acts at the D-serine binding site. Accordingly, both effects of nicotine: the enhancement of synaptic transmission and facilitation of long-term memory were eliminated by impairing glial cells with fluoroacetate, and were restored with exogenous D-serine. Together, these results show that glial D-serine is essential for the long-term effects of nicotine on synaptic plasticity and memory, and they highlight the roles of glial cells as key participants in brain functions. PMID:23185511

Long-term changes in pigmentation of arctic Daphnia provide potential for reconstructing aquatic UV exposure

NASA Astrophysics Data System (ADS)

Nevalainen, Liisa; Rantala, Marttiina V.; Luoto, Tomi P.; Ojala, Antti E. K.; Rautio, Milla

2016-07-01

Despite the biologically damaging impacts of solar ultraviolet radiation (UV) in nature, little is known about its natural variability, forcing mechanisms, and long-term effects on ecosystems and organisms. Arctic zooplankton, for example the aquatic keystone genus Daphnia (Crustacea, Cladocera) responds to biologically damaging UV by utilizing photoprotective strategies, including pigmentation. We examined the preservation and content of UV-screening pigments in fossil Daphnia remains (ephippia) in two arctic lake sediment cores from Cornwallis Island (Lake R1), Canada, and Spitsbergen (Lake Fugledammen), Svalbard. The aims were to document changes in the degree of UV-protective pigmentation throughout the past centuries, elucidate the adaptive responses of zooplankton to long-term variations in UV exposure, and estimate the potential of fossil zooplankton pigments in reconstructing aquatic UV regimes. The spectroscopic absorbance measurements of fossil Daphnia ephippia under UV (280-400 nm) and visible light (400-700 nm) spectral ranges indicated that melanin (absorbance maxima at UV wavebands 280-350 nm) and carotenoids (absorbance maxima at 400-450 nm) pigments were preserved in the ephippia in both sediment cores. Downcore measurements of the most important UV-protective pigment melanin (absorbance measured at 305 and 340 nm) showed marked long-term variations in the degree of melanisation. These variations likely represented long-term trends in aquatic UV exposure and were positively related with solar radiation intensity. The corresponding trends in melanisation and solar activity were disrupted at the turn of the 20th century in R1, but remained as strong in Fugledammen. The reversed trends in the R1 core were simultaneous with a significant aquatic community reorganization taking place in the lake, suggesting that recent environmental changes, likely related to climate warming had a local effect on pigmentation strategies. This time horizon is also

Reconciling long-term cultural diversity and short-term collective social behavior.

PubMed

Valori, Luca; Picciolo, Francesco; Allansdottir, Agnes; Garlaschelli, Diego

2012-01-24

An outstanding open problem is whether collective social phenomena occurring over short timescales can systematically reduce cultural heterogeneity in the long run, and whether offline and online human interactions contribute differently to the process. Theoretical models suggest that short-term collective behavior and long-term cultural diversity are mutually excluding, since they require very different levels of social influence. The latter jointly depends on two factors: the topology of the underlying social network and the overlap between individuals in multidimensional cultural space. However, while the empirical properties of social networks are intensively studied, little is known about the large-scale organization of real societies in cultural space, so that random input specifications are necessarily used in models. Here we use a large dataset to perform a high-dimensional analysis of the scientific beliefs of thousands of Europeans. We find that interopinion correlations determine a nontrivial ultrametric hierarchy of individuals in cultural space. When empirical data are used as inputs in models, ultrametricity has strong and counterintuitive effects. On short timescales, it facilitates a symmetry-breaking phase transition triggering coordinated social behavior. On long timescales, it suppresses cultural convergence by restricting it within disjoint groups. Moreover, ultrametricity implies that these results are surprisingly robust to modifications of the dynamical rules considered. Thus the empirical distribution of individuals in cultural space appears to systematically optimize the coexistence of short-term collective behavior and long-term cultural diversity, which can be realized simultaneously for the same moderate level of mutual influence in a diverse range of online and offline settings.

[Participation as Target of Social Medicine and Nursing Care: - Legal Definition of Long-Term Care Dependency - Strategies to Prevent Long-Term Care Dependency].

PubMed

Nüchtern, Elisabeth; Gansweid, Barbara; Gerber, Hans; von Mittelstaedt, Gert

2017-01-01

Objective: By the "Second Bill to Strengthen Long-Term Care", a new concept of long-term care dependency will be introduced, valid from 2017. Long-term care dependency according to Social Code XI will be defined covering more aspects than today. Therefore, the working group "Nursing Care" of the division "Social Medicine in Practice and Rehabilitation" in the German Society for Social Medicine and Prevention presents their results after working on the social medicine perspective of the definition and prevention of long-term care dependency. Methods: Both the definition and strategies to prevent long-term care dependency are systematically taken into consideration from the point of view of social medicine on the basis of the International Classification of Functioning, Disability and Health (ICF), as long-term care dependency means a defined condition of disability. Results: Both the current and the new concept of long-term care dependency focus activity limitations. The perspective of social medicine considers the interactions of health condition, its effects on daily activities and personal as well as environmental factors. From this point of view approaches for social benefits concerning prevention and rehabilitation can be identified systematically so as to work against the development and progression of long-term care dependency. The reference to the ICF can facilitate the communication between different professions. The new "graduation" of long-term care dependency would allow an international "translation" referring to the ICF. Conclusion: Experts from the field of social medicine as well as those of nursing care, care-givers and nursing researchers have in common the objective that persons in need of nursing care can participate in as many aspects of life of importance to them in an autonomous and self-determined way. The point of view of social medicine on long-term care dependency is fundamental for all occupational groups that are involved and for their

Ex vivo expanded cord blood cells provide rapid engraftment in fetal sheep but lack long-term engrafting potential.

PubMed

McNiece, Ian K; Almeida-Porada, Graça; Shpall, Elizabeth J; Zanjani, Esmail

2002-06-01

Cord blood (CB) products are becoming routinely used in unrelated allogeneic transplantation for smaller pediatric patients. Because of the low numbers of cells in CB compared to bone marrow or peripheral blood progenitor cells, their use is more limited in larger adults. Therefore, we developed ex vivo expansion conditions for CB and currently are transplanting ex vivo expanded CB products to patients receiving high-dose chemotherapy. As there is concern that ex vivo expansion may exhaust long-term engrafting cells, the current clinical protocols consist of both an expanded fraction and an unexpanded fraction. To determine the effect of expansion culture on long-term engrafting cells, we evaluated the short- and long-term engrafting potential of ex vivo expanded CB using a fetal sheep xenogeneic transplant model. CD 34(+) cells were selected from CB products and cultured in a two-step procedure in the presence of stem cell factor, megakaryocyte growth and differentiation factor, and granulocyte colony-stimulating factor for 14 days. Starting cells (CD34(+) cells), and cultured cells (day 7 and day 14 cells) were transplanted in 60-day-old fetal sheep and evaluated at various time points post transplant for the presence of human cells. Long-term engrafting cells were assessed by serial passage into secondary and tertiary recipients. Day 14 expanded CB cells provided more rapid engraftment than either the day 7 expanded cells or the day 0 cells; however, this engraftment was transient, and no human cells were detectable at 16 months post transplant in the animals that received the day 14 expanded cells. Day 0 cells had engrafted animals at 2 months post transplant and both the day 0 and day 7 cells persisted to 16 months or longer. In the secondary animals, the day 0 and day 7 cells engrafted equivalently at 3 months post transplant; however, no secondary engraftment resulted from the day 14 cells. The levels of engraftment in secondary animals receiving day 7 cells

The APP-Interacting Protein FE65 is Required for Hippocampus-Dependent Learning and Long-Term Potentiation

ERIC Educational Resources Information Center

Wang, Yan; Zhang, Ming; Moon, Changjong; Hu, Qubai; Wang, Baiping; Martin, George; Sun, Zhongsheng; Wang, Hongbing

2009-01-01

FE65 is expressed predominantly in the brain and interacts with the C-terminal domain of [beta]-amyloid precursor protein (APP). We examined hippocampus-dependent memory and in vivo long-term potentiation (LTP) at the CA1 synapses with isoform-specific FE65 knockout (p97FE65[superscript -/-]) mice. When examined using the Morris water maze,…

Long-Term Memories Bias Sensitivity and Target Selection in Complex Scenes

PubMed Central

Patai, Eva Zita; Doallo, Sonia; Nobre, Anna Christina

2014-01-01

In everyday situations we often rely on our memories to find what we are looking for in our cluttered environment. Recently, we developed a new experimental paradigm to investigate how long-term memory (LTM) can guide attention, and showed how the pre-exposure to a complex scene in which a target location had been learned facilitated the detection of the transient appearance of the target at the remembered location (Summerfield, Lepsien, Gitelman, Mesulam, & Nobre, 2006; Summerfield, Rao, Garside, & Nobre, 2011). The present study extends these findings by investigating whether and how LTM can enhance perceptual sensitivity to identify targets occurring within their complex scene context. Behavioral measures showed superior perceptual sensitivity (d′) for targets located in remembered spatial contexts. We used the N2pc event-related potential to test whether LTM modulated the process of selecting the target from its scene context. Surprisingly, in contrast to effects of visual spatial cues or implicit contextual cueing, LTM for target locations significantly attenuated the N2pc potential. We propose that the mechanism by which these explicitly available LTMs facilitate perceptual identification of targets may differ from mechanisms triggered by other types of top-down sources of information. PMID:23016670

Long-term treatment of an addictive personality.

PubMed

Seymour, Peter M

2003-01-01

There is infrequent discussion of long-term psychotherapy of persons with addiction, particularly in the self-psychology literature. In addition, some question whether long-term psychotherapy can be helpful in severe psychiatric disorders. The author describes the treatment of a woman with multiple diagnoses, including bulimia and alcohol and drug addiction, which took place over a period of almost 7 years. These issues are addressed from a self-psychological perspective, with progression of the treatment from early facilitation of a selfobject transference to more intense selfobject transference-countertransference states. Behavioral interventions (e.g., recommendation of inpatient chemical dependency treatment) are also discussed. The author describes the patient's dramatic progress and subsequent regression. Finally, there is a discussion of the addiction from self-psychological and biological perspectives of this woman's particular developmental and treatment issues, as well as a discussion of the confrontation and limit setting in a self-psychologically oriented treatment.

Severe acute intermittent hypoxia elicits phrenic long-term facilitation by a novel adenosine-dependent mechanism

PubMed Central

Nichols, Nicole L.; Dale, Erica A.

2012-01-01

Acute intermittent hypoxia [AIH; 3, 5-min episodes; 35–45 mmHg arterial Po2 (PaO2)] elicits serotonin-dependent phrenic long-term facilitation (pLTF), a form of phrenic motor facilitation (pMF) initiated by Gq protein-coupled metabotropic 5-HT2 receptors. An alternate pathway to pMF is induced by Gs protein-coupled metabotropic receptors, including adenosine A2A receptors. AIH-induced pLTF is dominated by the serotonin-dependent pathway and is actually restrained via inhibition from the adenosine-dependent pathway. Here, we hypothesized that severe AIH shifts pLTF from a serotonin-dependent to an adenosine-dependent form of pMF. pLTF induced by severe (25–30 mmHg PaO2) and moderate (45–55 mmHg PaO2) AIH were compared in anesthetized rats, with and without intrathecal (C4) spinal A2A (MSX-3, 130 ng/kg, 12 μl) or 5-HT receptor antagonist (methysergide, 300 μg/kg, 15 μl) injections. During severe, but not moderate AIH, progressive augmentation of the phrenic response during hypoxic episodes was observed. Severe AIH (78% ± 8% 90 min post-AIH, n = 6) elicited greater pLTF vs. moderate AIH (41% ± 12%, n = 8; P < 0.05). MSX-3 (28% ± 6%; n = 6; P < 0.05) attenuated pLTF following severe AIH, but enhanced pLTF following moderate AIH (86% ± 26%; n = 8; P < 0.05). Methysergide abolished pLTF after moderate AIH (12% ± 5%; n = 6; P = 0.035), but had no effect after severe AIH (66 ± 13%; n = 5; P > 0.05). Thus severe AIH shifts pLTF from a serotonin-dependent to an adenosine-dependent mechanism; the adenosinergic pathway inhibits the serotonergic pathway following moderate AIH. Here we demonstrate a novel adenosine-dependent pathway to pLTF following severe AIH. Shifts in the mechanisms of respiratory plasticity provide the ventilatory control system greater flexibility as challenges that differ in severity are confronted. PMID:22403346

FXR1P Limits Long-Term Memory, Long-Lasting Synaptic Potentiation, and de novo GluA2 Translation

PubMed Central

Jones, Emma V.; Altimimi, Haider F.; Farmer, W. Todd; Gandin, Valentina; Hanna, Edith; Zong, Ruiting; Barbon, Alessandro; Nelson, David L.; Topisirovic, Ivan; Rochford, Joseph; Stellwagen, David; Béïque, Jean-Claude; Murai, Keith K.

2014-01-01

SUMMARY Translational control of mRNAs allows for rapid and selective changes in synaptic protein expression, changes that are required for long-lasting plasticity and memory formation in the brain. Fragile X Related Protein 1 (FXR1P) is an RNA-binding protein that controls mRNA translation in non-neuronal cells and co-localizes with translational machinery in neurons. However, its neuronal mRNA targets and role in the brain are unknown. Here, we demonstrate that removal of FXR1P from the forebrain of postnatal mice selectively enhances long-term storage of spatial memories, hippocampal late-phase LTP (L-LTP) and de novo GluA2 synthesis. Furthermore, FXR1P binds specifically to the 5’UTR of GluA2 mRNA to repress translation and limit the amount of GluA2 incorporated at potentiated synapses. This study uncovers a new mechanism for regulating long-lasting synaptic plasticity and spatial memory formation and reveals an unexpected divergent role of FXR1P among Fragile X proteins in brain plasticity. PMID:25456134

Long-term no-till and stover retention each decrease the global warming potential of irrigated continuous corn

USDA-ARS?s Scientific Manuscript database

Over the last 50 years, the most increase in cultivated land area globally has been due to a doubling of irrigated land. Long-term agronomic management impacts on soil organic carbon (SOC) stocks, soil greenhouse gas (GHG) emis-sions, and global warming potential (GWP) in irrigated systems, however,...

A Single Brief Burst Induces GluR1-Dependent Associative Short-Term Potentiation: A Potential Mechanism for Short-Term Memory

ERIC Educational Resources Information Center

Erickson, Martha A.; Maramara, Lauren A.; Lisman, John

2010-01-01

Recent work showed that short-term memory (STM) is selectively reduced in GluR1 knockout mice. This raises the possibility that a form of synaptic modification dependent on GluR1 might underlie STM. Studies of synaptic plasticity have shown that stimuli too weak to induce long-term potentiation induce short-term potentiation (STP), a phenomenon…

Space ventures and society long-term perspectives

NASA Technical Reports Server (NTRS)

Brown, W. M.

1985-01-01

A futuristic evaluation of mankind's potential long term future in space is presented. Progress in space will not be inhibited by shortages of the Earth's physical resources, since long term economic growth will be focused on ways to constrain industrial productivity by changing social values, management styles, or government competence. Future technological progress is likely to accelerate with an emphasis on international cooperation, making possible such large joint projects as lunar colonies or space stations on Mars. The long term future in space looks exceedingly bright even in relatively pessimistic scenarios. The principal driving forces will be technological progress, commercial and public-oriented satellites, space industrialization, space travel, and eventually space colonization.

A Protein Synthesis and Nitric Oxide-Dependent Presynaptic Enhancement in Persistent Forms of Long-Term Potentiation

ERIC Educational Resources Information Center

Johnstone, Victoria P. A.; Raymond, Clarke R.

2011-01-01

Long-term potentiation (LTP) is an important process underlying learning and memory in the brain. At CA3-CA1 synapses in the hippocampus, three discrete forms of LTP (LTP1, 2, and 3) can be differentiated on the basis of maintenance and induction mechanisms. However, the relative roles of pre- and post-synaptic expression mechanisms in LTP1, 2,…

Planning the Transition to Long-Term Stewardship for the River Corridor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cearlock, C.S.; Lerch, J.A.; Sands, J.P.

2007-07-01

Long-term stewardship refers to all activities necessary to ensure protection of human health and the environment following completion of remediation, disposal, or stabilization of a site or a portion of a site. Efforts to establish the proposed approach and criteria to be met for long-term stewardship in the river corridor of the Hanford Site in Richland, Washington, are currently being established and a draft plan is expected to be completed in mid-2007 to facilitate planning for a smooth and seamless transition to long-term stewardship. Once the initial criteria have been established, supporting information will be gathered as the work proceeds.more » Near the end of cleanup actions under the River Corridor Closure Contract, these criteria will be finalized in a long-term stewardship plan that documents how the criteria have been met. In addition, the final long-term stewardship plan will also contain a proposed Finding of Suitability to Transfer in accordance with Comprehensive Environmental Response, Compensation, and Liability Act of 1980 Section 120(h) [1]. This final long-term stewardship plan will provide the foundation for post-River Corridor Closure Contract and management activities in the river corridor pending actual property transfer from the U.S. Department of Energy. (authors)« less

Melatonin administration impairs visuo-spatial performance and inhibits neocortical long-term potentiation in rats.

PubMed

Soto-Moyano, Rubén; Burgos, Héctor; Flores, Francisco; Valladares, Luis; Sierralta, Walter; Fernández, Victor; Pérez, Hernán; Hernández, Paula; Hernández, Alejandro

2006-10-01

Melatonin has been shown to inhibit long-term potentiation (LTP) in hippocampal slices of rats. Since LTP may be one of the main mechanisms by which memory traces are encoded and stored in the central nervous system, it is possible that melatonin could modulate cognitive performance by interfering with the cellular and/or molecular mechanisms involved in LTP. We investigated in rats the effects of intraperitoneally-administered melatonin (0.1, 1 and 10 mg/kg), its saline-ethanol solvent, or saline alone, on the acquisition of visuo-spatial memory as well as on the ability of the cerebral cortex to develop LTP in vivo. Visuo-spatial performance was assessed daily in rats, for 10 days, in an 8-arm radial maze, 30 min after they received a single daily dose of melatonin. Visual cortex LTP was determined in sodium pentobarbital anesthetized rats (65 mg/kg i.p.), by potentiating transcallosal evoked responses with a tetanizing train (312 Hz, 500 ms duration) 30 min after administration of a single dose of melatonin. Results showed that melatonin impaired visuo-spatial performance in rats, as revealed by the greater number of errors committed and time spent to solve the task in the radial maze. Melatonin also prevented the induction of neocortical LTP. It is concluded that melatonin, at the doses utilized in this study, could alter some forms of neocortical plasticity involved in short- and long-term visuo-spatial memories in rats.

Potential long-term storage of the predatory mite Phytoseiulus persimilis

USDA-ARS?s Scientific Manuscript database

Increasing the ability to store mass-reared natural enemies during periods or seasons of low demand is a critical need of the biocontrol industry. We tested the hypothesis that cryoprotectant or carbohydrate molecules can enhance long-term cold storage of a predatory mite Phytoseiulus persimilis At...

Enabling Long-Term Earth Science Research: Changing Data Practices (Invited)

NASA Astrophysics Data System (ADS)

Baker, K. S.

2013-12-01

Data stewardship plans are shaped by our shared experiences. As a result, community engagement and collaborative activities are central to the stewardship of data. Since modes and mechanisms of engagement have changed, we benefit from asking anew: ';Who are the communities?' and ';What are the lessons learned?'. Data stewardship with its long-term care perspective, is enriched by reflection on community experience. This presentation draws on data management issues and strategies originating from within long-term research communities as well as on recent studies informed by library and information science. Ethnographic case studies that capture project activities and histories are presented as resources for comparative analysis. Agency requirements and funding opportunities are stimulating collaborative endeavors focused on data re-use and archiving. Research groups including earth scientists, information professionals, and data systems designers are recognizing the possibilities for new ways of thinking about data in the digital arena. Together, these groups are re-conceptualizing and reconfiguring for data management and data curation. A differentiation between managing data for local use and production of data for re-use remotely in locations and fields remote from the data origin is just one example of the concepts emerging to facilitate development of data management. While earth scientists as data generators have the responsibility to plan new workflows and documentation practices, data and information specialists have responsibility to promote best practices as well as to facilitate the development of community resources such as controlled vocabularies and data dictionaries. With data-centric activities and changing data practices, the potential for creating dynamic community information environments in conjunction with development of data facilities exists but remains elusive.

Long-Term Habituation of the C-Start Escape Response in Zebrafish Larvae

PubMed Central

Roberts, Adam C.; Pearce, Kaycey C.; Choe, Ronny C.; Alzagatiti, Joseph B.; Yeung, Anthony K.; Bill, Brent R.; Glanzman, David L.

2016-01-01

The cellular and molecular basis of long-term memory in vertebrates remains poorly understood. Knowledge regarding long-term memory has been impeded by the enormous complexity of the vertebrate brain, particularly the mammalian brain, as well as by the relative complexity of the behavioral alterations examined in most studies of long-term memory in vertebrates. Here, we demonstrate a long-term form of nonassociative learning—specifically, long-term habituation (LTH)—of a simple reflexive escape response, the C-start, in zebrafish larvae. The C-start is triggered by the activation of one of a pair of giant neurons in the zebrafish’s hindbrain, the Mauthner cells. We show that LTH of the C-start requires the activity of NMDA receptors and involves macromolecular synthesis. We further show that the long-term habituated reflex can by rapidly dishabituated by a brief tactile stimulus. Our results set the stage for rigorous, mechanistic investigations of the long-term memory for habituation of a reflexive behavioral response, one that is mediated by a relatively simple, neurobiologically tractable, neural circuit. Moreover, the demonstration of NMDAR and transcriptionally dependent LTH in a translucent vertebrate organism should facilitate the use of optical recording, and optogenetic manipulation, of neuronal activity to elucidate the cellular basis of a long-term vertebrate memory. PMID:27555232

Dendritic sodium spikes are required for long-term potentiation at distal synapses on hippocampal pyramidal neurons

PubMed Central

Kim, Yujin; Hsu, Ching-Lung; Cembrowski, Mark S; Mensh, Brett D; Spruston, Nelson

2015-01-01

Dendritic integration of synaptic inputs mediates rapid neural computation as well as longer-lasting plasticity. Several channel types can mediate dendritically initiated spikes (dSpikes), which may impact information processing and storage across multiple timescales; however, the roles of different channels in the rapid vs long-term effects of dSpikes are unknown. We show here that dSpikes mediated by Nav channels (blocked by a low concentration of TTX) are required for long-term potentiation (LTP) in the distal apical dendrites of hippocampal pyramidal neurons. Furthermore, imaging, simulations, and buffering experiments all support a model whereby fast Nav channel-mediated dSpikes (Na-dSpikes) contribute to LTP induction by promoting large, transient, localized increases in intracellular calcium concentration near the calcium-conducting pores of NMDAR and L-type Cav channels. Thus, in addition to contributing to rapid neural processing, Na-dSpikes are likely to contribute to memory formation via their role in long-lasting synaptic plasticity. DOI: http://dx.doi.org/10.7554/eLife.06414.001 PMID:26247712

Efficacy of lifestyle modification for long-term weight control.

PubMed

Wadden, Thomas A; Butryn, Meghan L; Byrne, Kirstin J

2004-12-01

A comprehensive program of lifestyle modification induces loss of approximately 10% of initial weight in 16 to 26 weeks, as revealed by a review of recent randomized controlled trials, including the Diabetes Prevention Program. Long-term weight control is facilitated by continued patient-therapist contact, whether provided in person or by telephone, mail, or e-mail. High levels of physical activity and the consumption of low-calorie, portion-controlled meals, including liquid meal replacements, can also help maintain weight loss. Additional studies are needed of the effects of macronutrient content (e.g., low-fat vs. low-carbohydrate diets) on long-term changes in weight and health. Research also is needed on effective methods of providing comprehensive weight loss control to the millions of Americans who need it.

Dynamical model of long-term synaptic plasticity

PubMed Central

Abarbanel, Henry D. I.; Huerta, R.; Rabinovich, M. I.

2002-01-01

Long-term synaptic plasticity leading to enhancement in synaptic efficacy (long-term potentiation, LTP) or decrease in synaptic efficacy (long-term depression, LTD) is widely regarded as underlying learning and memory in nervous systems. LTP and LTD at excitatory neuronal synapses are observed to be induced by precise timing of pre- and postsynaptic events. Modification of synaptic transmission in long-term plasticity is a complex process involving many pathways; for example, it is also known that both forms of synaptic plasticity can be induced by various time courses of Ca2+ introduction into the postsynaptic cell. We present a phenomenological description of a two-component process for synaptic plasticity. Our dynamical model reproduces the spike time-dependent plasticity of excitatory synapses as a function of relative timing between pre- and postsynaptic events, as observed in recent experiments. The model accounts for LTP and LTD when the postsynaptic cell is voltage clamped and depolarized (LTP) or hyperpolarized (LTD) and no postsynaptic action potentials are evoked. We are also able to connect our model with the Bienenstock, Cooper, and Munro rule. We give model predictions for changes in synaptic strength when periodic spike trains of varying frequency and Poisson distributed spike trains with varying average frequency are presented pre- and postsynaptically. When the frequency of spike presentation exceeds ≈30–40 Hz, only LTP is induced. PMID:12114531

Integrated modeling of long-term vegetation and hydrologic dynamics in Rocky Mountain watersheds

Treesearch

Robert Steven Ahl

2007-01-01

Changes in forest structure resulting from natural disturbances, or managed treatments, can have negative and long lasting impacts on water resources. To facilitate integrated management of forest and water resources, a System for Long-Term Integrated Management Modeling (SLIMM) was developed. By combining two spatially explicit, continuous time models, vegetation...

[Role of long-term potentiation in mechanism of the conditioned learning].

PubMed

Tsvetkov, E A; Suderevskaia, E I; Veselkin, N P

2011-01-01

The review analyzes the fundamental problem of study of the neuronal mechanisms underlying processes of learning and memory. As a neuronal models of these phenomena there was considered one of the cellular phenomena that has characteristics similar with those in the process of "remembering"--such as the long-term potentiation (LTP). LTP is easily reproduced in certain synapses of the central nervous system, specifically in synapses of hippocampus and amygdala. As to the behavioral model of learning, there was used the conditioned learning, in frames of which production of the context-dependent/independent conditioned reaction was considered. Analysis of literature data has allowed showing that various stages of LTP produced on synapses of hippocampus or amygdala can be comparable with certain phase of the process of learning. Based on the exposed material the authors conclude that plastic changes of synapses of hippocampus and amygdala can represent the morphological substrate of some kinds of learning and memory.

Long-term neurocognitive outcome and auditory event-related potentials after complex febrile seizures in children.

PubMed

Tsai, Min-Lan; Hung, Kun-Long; Tsan, Ying-Ying; Tung, William Tao-Hsin

2015-06-01

Whether prolonged or complex febrile seizures (FS) produce long-term injury to the hippocampus is a critical question concerning the neurocognitive outcome of these seizures. Long-term event-related evoked potential (ERP) recording from the scalp is a noninvasive technique reflecting the sensory and cognitive processes associated with attention tasks. This study aimed to investigate the long-term outcome of neurocognitive and attention functions and evaluated auditory event-related potentials in children who have experienced complex FS in comparison with other types of FS. One hundred and forty-seven children aged more than 6 years who had experienced complex FS, simple single FS, simple recurrent FS, or afebrile seizures (AFS) after FS and age-matched healthy controls were enrolled. Patients were evaluated with Wechsler Intelligence Scale for Children (WISC; Chinese WISC-IV) scores, behavior test scores (Chinese version of Conners' continuous performance test, CPT II V.5), and behavior rating scales. Auditory ERPs were recorded in each patient. Patients who had experienced complex FS exhibited significantly lower full-scale intelligence quotient (FSIQ), perceptual reasoning index, and working memory index scores than did the control group but did not show significant differences in CPT scores, behavior rating scales, or ERP latencies and amplitude compared with the other groups with FS. We found a significant decrease in the FSIQ and four indices of the WISC-IV, higher behavior rating scales, a trend of increased CPT II scores, and significantly delayed P300 latency and reduced P300 amplitude in the patients with AFS after FS. We conclude that there is an effect on cognitive function in children who have experienced complex FS and patients who developed AFS after FS. The results indicated that the WISC-IV is more sensitive in detecting cognitive abnormality than ERP. Cognition impairment, including perceptual reasoning and working memory defects, was identified in

Anticipatory eye movements and long-term memory in early infancy.

PubMed

Wong-Kee-You, Audrey M B; Adler, Scott A

2016-11-01

Advances in our understanding of long-term memory in early infancy have been made possible by studies that have used the Rovee-Collier's mobile conjugate reinforcement paradigm and its variants. One function that has been attributed to long-term memory is the formation of expectations (Rovee-Collier & Hayne, 1987); consequently, a long-term memory representation should be established during expectation formation. To examine this prediction and potentially open the door on a new paradigm for exploring infants' long-term memory, using the Visual Expectation Paradigm (Haith, Hazan, & Goodman, 1988), 3-month-old infants were trained to form an expectation for predictable color and spatial information of picture events and emit anticipatory eye movements to those events. One day later, infants' anticipatory eye movements decreased in number relative to the end of training when the predictable colors were changed but not when the spatial location of the predictable color events was changed. These findings confirm that information encoded during expectation formation are stored in long-term memory, as hypothesized by Rovee-Collier and colleagues. Further, this research suggests that eye movements are potentially viable measures of long-term memory in infancy, providing confirmatory evidence for early mnemonic processes. © 2016 Wiley Periodicals, Inc.

Adjuvant psychological therapy in long-term endocrine conditions.

PubMed

Daniels, J; Turner-Cobb, J M

2017-06-01

Consideration of psychological distress in long-term endocrine conditions is of vital importance given the prevalence of anxiety and depression in such disorders. Poor mental health can lead to compromised self-care, higher utilization of health services, lower rates of adherence, reduced quality of life and ultimately poorer outcomes. Adjuvant psychological therapy offers an effective resource to reduce distress in endocrine conditions. While the vast majority of work in this area has focused on psychological screening and intervention in diabetes, identification and recognition of psychological distress are equally important in other endocrinological conditions, with supportive evidence in polycystic ovary syndrome and Addison's disease. Referral pathways and recommendations set out by UK guidelines and the Department of Health mandate requires greater attention across a wider range of long-term endocrine conditions to facilitate improved quality of life and health outcome. © 2017 John Wiley & Sons Ltd.

Potential breeding distributions of U.S. birds predicted with both short-term variability and long-term average climate data

Treesearch

Brooke L. Bateman; Anna M. Pidgeon; Volker C. Radeloff; Curtis H. Flather; Jeremy VanDerWal; H. Resit Akcakaya; Wayne E. Thogmartin; Thomas P. Albright; Stephen J. Vavrus; Patricia J. Heglund

2016-01-01

Climate conditions, such as temperature or precipitation, averaged over several decades strongly affect species distributions, as evidenced by experimental results and a plethora of models demonstrating statistical relations between species occurrences and long-term climate averages. However, long-term averages can conceal climate changes that have occurred in...

Clinical trials with rasagiline: evidence for short-term and long-term effects.

PubMed

Siderowf, Andrew; Stern, Matthew

2006-05-23

Rasagiline (N-propargyl-1 (R)-aminoindan) is a selective, potent irreversible inhibitor of MAO-B that possesses neuroprotective and anti-apoptotic properties in a variety of in vitro and in vivo animal models relevant to Parkinson's disease (PD). Several randomized controlled clinical trials have demonstrated the safety and efficacy of rasagiline as monotherapy in PD and as adjunctive therapy for patients receiving levodopa. In addition, the 1-year randomized, delayed-start analysis of the TEMPO study suggests that rasagiline may slow the rate of progression of PD. The randomized delayed-start paradigm has potential to differentiate short-term symptomatic effects from long-term effects of anti-parkinsonian agents. In the future, long-term trials to examine the potential disease-modifying effects of rasagiline, which incorporate biological markers as well as clinical endpoints, may further elucidate the role of rasagiline in the treatment of both early and advanced PD.

Group long-term care insurance: decision-making factors and implications for financing long-term care.

PubMed

Stum, Marlene S

2008-01-01

This study proposes and tests a systemic family decision-making framework to understand group long-term care insurance (LTCI) enrollment decisions. A random sample of public employees who were offered group LTCI as a workplace benefit were examined. Findings reveal very good predictive efficacy for the overall conceptual framework with a pseudo R2 value of .687, and reinforced the contributions of factors within the family system. Enrollees were more likely to have discussed the decision with others, used information sources, and had prior experience when compared to non-enrollees. Perceived health status, financial knowledge, attitudes regarding the role of private insurance, risk taking, and coverage features were additional factors related to enrollment decisions. The findings help to inform policymakers about the potential of LTCI as one strategy for financing long-term care.

Long-term venous access using a subcutaneous implantable drug delivery system.

PubMed Central

Soo, K. C.; Davidson, T. I.; Selby, P.; Westbury, G.

1985-01-01

To facilitate long-term venous access in patients receiving chemotherapy, a subcutaneous totally implantable system (Port-a-Cath, Phamacia) has been used in 14 patients. The method of implantation and the advantages over conventional central venous catheters are discussed. The expense of the system necessitates careful patient selection. PMID:4037644

Using OpenTarget to Generate Potential Countermeasures for Long-Term Space Exposure from Data Available on GeneLab

NASA Technical Reports Server (NTRS)

Beheshti, Afshin

2018-01-01

GeneLab as a general tool for the scientific community; Utilizing GeneLab datasets to generate hypothesis and determining potential biological targets against health risks due to long-term space missions; How can OpenTarget be used to discover novel drugs to test as countermeasures that can be utilized by astronauts.

The expression of long-term potentiation: reconciling the preists and the postivists

PubMed Central

MacDougall, Matthew J.; Fine, Alan

2014-01-01

Long-term potentiation (LTP) of excitatory synaptic transmission in the hippocampus has been investigated in great detail over the past 40 years. Where and how LTP is actually expressed, however, remain controversial issues. Considerable evidence has been offered to support both pre- and postsynaptic contributions to LTP expression. Though it is widely held that postsynaptic expression mechanisms are the primary contributors to LTP expression, evidence for that conclusion is amenable to alternative explanations. Here, we briefly review some key contributions to the ‘locus’ debate and describe data that support a dominant role for presynaptic mechanisms. Recognition of the state-dependency of expression mechanisms, and consideration of the consequences of the spatial relationship between postsynaptic glutamate receptors and presynaptic vesicular release sites, lead to a model that may reconcile views from both sides of the synapse. PMID:24298138

Change in microbial community in landfill refuse contaminated with antibiotics facilitates denitrification more than the increase in ARG over long-term

NASA Astrophysics Data System (ADS)

Wu, Dong; Chen, Guanzhou; Zhang, Xiaojun; Yang, Kai; Xie, Bing

2017-01-01

In this study, the addition of sulfamethazine (SMT) to landfill refuse decreased nitrogen intermediates (e.g. N2O and NO) and dinitrogen (N2) gas fluxes to <0.5 μg-N/kg-refuse·h-1, while the N2O and N2 flux were at ~1.5 and 5.0 μg-N/kg-refuse·h-1 respectively in samples to which oxytetracycline (OTC) had been added. The ARG (antibiotic resistance gene) levels in the refuse increased tenfold after long-term exposure to antibiotics, followed by a fourfold increase in the N2 flux, but SMT-amended samples with the largest resistome facilitated the denitrification (the nitrogen accumulated as NO gas at ~6 μg-N/kg-refuse·h-1) to a lesser extent than OTC-amended samples. Further, deep sequencing results show that long-term OTC exposure partially substituted Hyphomicrobium, Fulvivirga, and Caldilinea (>5%) for the dominant bacterial hosts (Rhodothermus, ~20%) harboring nosZ and norB genes that significantly correlated with nitrogen emission pattern, while sulfamethazine amendment completely reduced the relative abundance of the “original inhabitants” functioning to produce NOx gas reduction. The main ARG carriers (Pseudomonas) that were substantially enriched in the SMT group had lower levels of denitrifying functional genes, which could imply that denitrification is influenced more by bacterial dynamics than by abundance of ARGs under antibiotic pressures.

Scientific Understanding from Long Term Observations: Insights from the Long Term Ecological Research (LTER) Program

NASA Astrophysics Data System (ADS)

Gosz, J.

2001-12-01

estuaries below by removing all incoming freshwater. At Toolik Lake, long-term experiments of removing top predators from the good web of lakes showed dramatic alterations of lake populations of small fish and zooplankton. In New Mexico, LTER research on small mammal populations is successfully predicting rodent increases and the potential for increased zoonotic diseases such as Hantavirus and bubonic plague. This ability to forecast based on El Nino prediction is being used to increase scientific awareness and public health awareness through media based communication with the public. In Oregon, the Andrews Forest LTER program has had long, strong links with natural resource policy and management. Basic understanding of forest-stream interactions, characteristics of old-growth forests, roles of woody debris in temperate forest ecosystems, invertebrate biodiversity and ecosystem function have been incorporated in management guidelines, plans and regulations for public and private lands throughout the Pacific Northwest. Other examples of the values of long-term research and monitoring will be presented.

Planning for Long-Term Follow-Up: Strategies Learned from Longitudinal Studies.

PubMed

Hill, Karl G; Woodward, Danielle; Woelfel, Tiffany; Hawkins, J David; Green, Sara

2016-10-01

Preventive interventions are often designed and tested with the immediate program period in mind, and little thought that the intervention sample might be followed up for years or even decades beyond the initial trial. However, depending on the type of intervention and the nature of the outcomes, long-term follow-up may well be appropriate. The advantages of long-term follow-up of preventive interventions are discussed and include the capacity to examine program effects across multiple later life outcomes, the ability to examine the etiological processes involved in the development of the outcomes of interest, and the ability to provide more concrete estimates of the relative benefits and costs of an intervention. In addition, researchers have identified potential methodological risks of long-term follow-up such as inflation of type 1 error through post hoc selection of outcomes, selection bias, and problems stemming from attrition over time. The present paper presents a set of seven recommendations for the design or evaluation of studies for potential long-term follow-up organized under four areas: Intervention Logic Model, Developmental Theory and Measurement Issues; Design for Retention; Dealing with Missing Data; and Unique Considerations for Intervention Studies. These recommendations include conceptual considerations in the design of a study, pragmatic concerns in the design and implementation of the data collection for long-term follow-up, as well as criteria to be considered for the evaluation of an existing intervention for potential for long-term follow-up. Concrete examples from existing intervention studies that have been followed up over the long term are provided.

Planning for Long-Term Follow-up: Strategies Learned from Longitudinal Studies

PubMed Central

Hill, Karl G.; Woodward, Danielle; Woelfel, Tiffany; Hawkins, J. David; Green, Sara

2017-01-01

Preventive interventions are often designed and tested with the immediate program period in mind, and little thought that the intervention sample might be followed up for years, or even decades beyond the initial trial. However, depending on the type of intervention and the nature of the outcomes, long-term follow-up may well be appropriate. The advantages of long-term follow-up of preventive interventions are discussed, and include the capacity to examine program effects across multiple later life outcomes, the ability to examine the etiological processes involved in the development of the outcomes of interest and the ability to provide more concrete estimates of the relative benefits and costs of an intervention. In addition, researchers have identified potential methodological risks of long-term follow-up such as inflation of type 1 error through post-hoc selection of outcomes, selection bias and problems stemming from attrition over time. The present paper presents a set of seven recommendations for the design or evaluation of studies for potential long-term follow-up organized under four areas: Intervention Logic Model, Developmental Theory and Measurement Issues; Design for Retention; Dealing with Missing Data; and Unique Considerations for Intervention Studies. These recommendations include conceptual considerations in the design of a study, pragmatic concerns in the design and implementation of the data collection for long-term follow-up, as well as criteria to be considered for the evaluation of an existing intervention for potential for long-term follow-up. Concrete examples from existing intervention studies that have been followed up over the long-term are provided. PMID:26453453

Long-term ecological research in a human-dominated world

Treesearch

G. Philip Robertson; Scott L. Collins; David R. Foster; Nicholas Brokaw; Hugh W. Ducklow; Ted L. Gragson; Corinna Gries; Stephen K. Hamilton; A. David McGuire; John C. Moore; Emily H. Stanley; Robert B. Waide; Mark W. Williams

2012-01-01

The US Long Term Ecological Research (LTER) Network enters its fourth decade with a distinguished record of achievement in ecological science. The value of long-term observations and experiments has never been more important for testing ecological theory and for addressing today’s most difficult environmental challenges. The network’s potential for tackling emergent...

Long-term potentiation in hilar circuitry modulates gating by the dentate gyrus.

PubMed

Wright, Brandon J; Jackson, Meyer B

2014-07-16

The dentate gyrus serves as a gateway to the hippocampus, filtering and processing sensory inputs as an animal explores its environment. The hilus occupies a strategic position within the dentate gyrus from which it can play a pivotal role in these functions. Inputs from dentate granule cells converge on the hilus, and excitatory hilar mossy cells redistribute these signals back to granule cells to transform a pattern of cortical input into a new pattern of output to the hippocampal CA3 region. Using voltage-sensitive dye to image electrical activity in rat hippocampal slices, we explored how long-term potentiation (LTP) of different excitatory synapses modifies the flow of information. Theta burst stimulation of the perforant path potentiated responses throughout the molecular layer, but left responses in the CA3 region unchanged. By contrast, theta burst stimulation of the granule cell layer potentiated responses throughout the molecular layer, as well as in the CA3 region. Theta burst stimulation of the granule cell layer potentiated CA3 responses not only to granule cell layer stimulation but also to perforant path stimulation. Potentiation of responses in the CA3 region reflected NMDA receptor-dependent LTP of upstream synapses between granule cells and mossy cells, with no detectable contribution from NMDA receptor-independent LTP of local CA3 mossy fiber synapses. Potentiation of transmission to the CA3 region required LTP in both granule cell→mossy cell and mossy cell→granule cell synapses. This bidirectional plasticity enables hilar circuitry to regulate the flow of information through the dentate gyrus and on to the hippocampus. Copyright © 2014 the authors 0270-6474/14/349743-11$15.00/0.

Dispositional optimism as predictor of outcome in short- and long-term psychotherapy.

PubMed

Heinonen, Erkki; Heiskanen, Tiia; Lindfors, Olavi; Härkäpää, Kristiina; Knekt, Paul

2017-09-01

Dispositional optimism predicts various beneficial outcomes in somatic health and treatment, but has been little studied in psychotherapy. This study investigated whether an optimistic disposition differentially predicts patients' ability to benefit from short-term versus long-term psychotherapy. A total of 326 adult outpatients with mood and/or anxiety disorder were randomized into short-term (solution-focused or short-term psychodynamic) or long-term psychodynamic therapy and followed up for 3 years. Dispositional optimism was assessed by patients at baseline with the self-rated Life Orientation Test (LOT) questionnaire. Outcome was assessed at baseline and seven times during the follow-up, in terms of depressive (BDI, HDRS), anxiety (SCL-90-ANX, HARS), and general psychiatric symptoms (SCL-90-GSI), all seven follow-up points including patients' self-reports and three including interview-based measures. Lower dispositional optimism predicted faster symptom reduction in short-term than in long-term psychotherapy. Higher optimism predicted equally rapid and eventually greater benefits in long-term, as compared to short-term, psychotherapy. Weaker optimism appeared to predict sustenance of problems early in long-term therapy. Stronger optimism seems to best facilitate engaging in and benefiting from a long-term therapy process. Closer research might clarify the psychological processes responsible for these effects and help fine-tune both briefer and longer interventions to optimize treatment effectiveness for particular patients and their psychological qualities. Weaker dispositional optimism does not appear to inhibit brief therapy from effecting symptomatic recovery. Patients with weaker optimism do not seem to gain added benefits from long-term therapy, but instead may be susceptible to prolonged psychiatric symptoms in the early stages of long-term therapy. © 2016 The British Psychological Society.

Alpha2-adrenoceptor modulation of long-term potentiation elicited in vivo in rat occipital cortex.

PubMed

Mondaca, Mauricio; Hernández, Alejandro; Pérez, Hernán; Valladares, Luis; Sierralta, Walter; Fernández, Victor; Soto-Moyano, Rubén

2004-09-24

Pretreatment with the alpha(2)-adrenoceptor agonist clonidine (31.25, 62.5, or 125 microg/kg, i.p.) dose-dependently reduced long-term potentiation (LTP) elicited in vivo in the occipital cortex of anesthetized rats, whereas pretreatment with the alpha(2)-adrenoceptor antagonist yohimbine (0.133, 0.4, or 1.2 mg/kg, i.p.) increased neocortical LTP in a dose-dependent fashion. These effects could be related to the reported disruptive and facilitatory actions induced on memory formation by pretreatment with alpha(2)-adrenoceptor agonists and antagonists, respectively.

Long-term stability of nanostructured thin film electrodes at operating potentials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahluwalia, Rajesh K.; Peng, J. -K.; Wang, X.

Long-term stability of nanostructured thin film (NSTF) catalysts at operating potentials has been investigated. Compared to high surface area Pt/C catalysts, NSTF electrodes show 20–50x smaller F – emission rates (FER) because of their high specific activity for oxygen reduction reaction (ORR), but are susceptible to poisoning by the products of membrane degradation because of their low electrochemically active surface area (ECSA). The observed voltage degradation rates at potentials corresponding to 1–1.5 A/cm 2 current density are much higher than the allowable 13–14 μV/h. Although F – is not itself responsible for performance decay, cumulative fluoride release (CFR) is amore » good marker for catalyst surface contamination. The observed performance decay is not only due to loss of active Pt sites but also adsorbed impurities impeding ORR kinetics. There is a strong correlation between measured CFR and observed decrease in specific ORR activity and limiting current density and increase in mass transfer overpotentials. Furthermore, the correlations indicate that the target of <10% lifetime performance degradation can be achieved by restricting CFR in NSTF electrodes to 0.7 μg/cm 2, as may be possible with more stable membranes, higher surface area NSTF catalysts, and cell operation at lower temperatures and higher relative humidities.« less

Long-term stability of nanostructured thin film electrodes at operating potentials

DOE PAGES

Ahluwalia, Rajesh K.; Peng, J. -K.; Wang, X.; ...

2017-02-09

Long-term stability of nanostructured thin film (NSTF) catalysts at operating potentials has been investigated. Compared to high surface area Pt/C catalysts, NSTF electrodes show 20–50x smaller F – emission rates (FER) because of their high specific activity for oxygen reduction reaction (ORR), but are susceptible to poisoning by the products of membrane degradation because of their low electrochemically active surface area (ECSA). The observed voltage degradation rates at potentials corresponding to 1–1.5 A/cm 2 current density are much higher than the allowable 13–14 μV/h. Although F – is not itself responsible for performance decay, cumulative fluoride release (CFR) is amore » good marker for catalyst surface contamination. The observed performance decay is not only due to loss of active Pt sites but also adsorbed impurities impeding ORR kinetics. There is a strong correlation between measured CFR and observed decrease in specific ORR activity and limiting current density and increase in mass transfer overpotentials. Furthermore, the correlations indicate that the target of <10% lifetime performance degradation can be achieved by restricting CFR in NSTF electrodes to 0.7 μg/cm 2, as may be possible with more stable membranes, higher surface area NSTF catalysts, and cell operation at lower temperatures and higher relative humidities.« less

Synaptic depolarization is more effective than back-propagating action potentials during induction of associative long-term potentiation in hippocampal pyramidal neurons.

PubMed

Hardie, Jason; Spruston, Nelson

2009-03-11

Long-term potentiation (LTP) requires postsynaptic depolarization that can result from EPSPs paired with action potentials or larger EPSPs that trigger dendritic spikes. We explored the relative contribution of these sources of depolarization to LTP induction during synaptically driven action potential firing in hippocampal CA1 pyramidal neurons. Pairing of a weak test input with a strong input resulted in large LTP (approximately 75% increase) when the weak and strong inputs were both located in the apical dendrites. This form of LTP did not require somatic action potentials. When the strong input was located in the basal dendrites, the resulting LTP was smaller (< or =25% increase). Pairing the test input with somatically evoked action potentials mimicked this form of LTP. Thus, back-propagating action potentials may contribute to modest LTP, but local synaptic depolarization and/or dendritic spikes mediate a stronger form of LTP that requires spatial proximity of the associated synaptic inputs.

Interaction of Inhibitory and Facilitatory Effects of Conditioning Trials on Long-Term Memory Formation

ERIC Educational Resources Information Center

Hosono, Shouhei; Matsumoto, Yukihisa; Mizunami, Makoto

2016-01-01

Animals learn through experience and consolidate the memories into long-time storage. Conditioning parameters to induce protein synthesis-dependent long-term memory (LTM) have been the subject of extensive studies in many animals. Here we found a case in which a conditioning trial inhibits or facilitates LTM formation depending on the intervals…

[Long-term psychiatric hospitalizations].

PubMed

Plancke, L; Amariei, A

2017-02-01

Long-term hospitalizations in psychiatry raise the question of desocialisation of the patients and the inherent costs. Individual indicators were extracted from a medical administrative database containing full-time psychiatric hospitalizations for the period 2011-2013 of people over 16 years old living in the French region of Nord-Pas-de-Calais. We calculated the proportion of people who had experienced a hospitalization with a duration of 292 days or more during the study period. A bivariate analysis was conducted, then ecological data (level of health-care offer, the deprivation index and the size of the municipalities of residence) were included into a multilevel regression model in order to identify the factors significantly related to variability of long-term hospitalization rates. Among hospitalized individuals in psychiatry, 2.6% had had at least one hospitalization of 292 days or more during the observation period; the number of days in long-term hospitalization represented 22.5% of the total of days of full-time hospitalization in psychiatry. The bivariate analysis revealed that seniority in the psychiatric system was strongly correlated with long hospitalization rates. In the multivariate analysis, the individual indicators the most related to an increased risk of long-term hospitalization were: total lack of autonomy (OR=9.0; 95% CI: 6.7-12.2; P<001); diagnoses of psychological development disorders (OR=9.7; CI95%: 4.5-20.6; P<.001); mental retardation (OR=4.5; CI95%: 2.5-8.2; P<.001): schizophrenia (OR=3.0; CI95%: 1.7-5.2; P<.001); compulsory hospitalization (OR=1.7; CI95%: 1.4-2.1; P<.001); having experienced therapeutic isolation (OR=1.8; CI95%: 1.5-2.1; P<.001). Variations of long-term hospitalization rates depending on the type of establishment were very high, but the density of hospital beds or intensity of ambulatory activity services were not significantly linked to long-term hospitalization. The inhabitants of small urban units had

Loganin enhances long-term potentiation and recovers scopolamine-induced learning and memory impairments.

PubMed

Hwang, Eun-Sang; Kim, Hyun-Bum; Lee, Seok; Kim, Min-Ji; Lee, Sung-Ok; Han, Seung-Moo; Maeng, Sungho; Park, Ji-Ho

2017-03-15

Although the incidence rate of dementia is rapidly growing in the aged population, therapeutic and preventive reagents are still suboptimal. Various model systems are used for the development of such reagents in which scopolamine is one of the favorable pharmacological tools widely applied. Loganin is a major iridoid glycoside obtained from Corni fructus (Cornusofficinalis et Zucc) and demonstrated to have anti-inflammatory, anti-tumor and osteoporosis prevention effects. It has also been found to attenuate Aβ-induced inflammatory reactions and ameliorate memory deficits induced by scopolamine. However, there has been limited information available on how loganin affects learning and memory both electrophysiologically and behaviorally. To assess its effect on learning and memory, we investigated the influence of acute loganin administration on long-term potentiation (LTP) using organotypic cultured hippocampal tissues. In addition, we measured the effects of loganin on the behavior performance related to avoidance memory, short-term spatial navigation memory and long-term spatial learning and memory in the passive avoidance, Y-maze, and Morris water maze learning paradigms, respectively. Loganin dose-dependently increased the total activity of fEPSP after high frequency stimulation and attenuated scopolamine-induced blockade of fEPSP in the hippocampal CA1 area. In accordance with these findings, loganin behaviorally attenuated scopolamine-induced shortening of step-through latency in the passive avoidance test, reduced the percent alternation in the Y-maze, and increased memory retention in the Morris water maze test. These results indicate that loganin can effectively block cholinergic muscarinic receptor blockade -induced deterioration of LTP and memory related behavioral performance. Based on these findings, loganin may aid in the prevention and treatment of Alzheimer's disease and learning and memory-deficit disorders in the future. Copyright © 2017 Elsevier

Platelet-activating factor and group I metabotropic glutamate receptors interact for full development and maintenance of long-term potentiation in the rat medial vestibular nuclei.

PubMed

Grassi, S; Francescangeli, E; Goracci, G; Pettorossi, V E

1999-01-01

In rat brainstem slices, we investigated the interaction between platelet-activating factor and group I metabotropic glutamate receptors in mediating long-term potentiation within the medial vestibular nuclei. We analysed the N1 field potential wave evoked in the ventral portion of the medial vestibular nuclei by primary vestibular afferent stimulation. The group I metabotropic glutamate receptor antagonist, (R,S)-1-aminoindan-1,5-dicarboxylic acid, prevented long-term potentiation induced by a platelet-activating factor analogue [1-O-hexadecyl-2-O-(methylcarbamyl)-sn-glycero-3-phosphocholine], as well as the full development of potentiation, induced by high-frequency stimulation under the blocking agent for synaptosomal platelet-activating factor receptors (ginkolide B), at drug washout. However, potentiation directly induced by the group I glutamate metabotropic receptor agonist, (R,S)-3,5-dihydroxyphenylglycine, was reduced by ginkolide B. These findings suggest that platelet-activating factor, whether exogenous or released following potentiation induction, exerts its effect through presynaptic group I metabotropic glutamate receptors, mediating the increase of glutamate release. In addition, we found that this mechanism, which led to full potentiation through presynaptic group I metabotropic glutamate receptor activation, was inactivated soon after application of potentiation-inducing stimulus. In fact, the long-lasting block of the platelet-activating factor and metabotropic glutamate receptors prevented the full potentiation development and the induced potentiation progressively declined to null. Moreover, ginkolide B, given when high-frequency-dependent potentiation was established, only reduced it within 5 min after potentiation induction. We conclude that to fully develop vestibular long-term potentiation requires presynaptic events. Platelet-activating factor, released after the activation of postsynaptic mechanisms which induce potentiation, is necessary

Cytokines and cytokine networks target neurons to modulate long-term potentiation

PubMed Central

Prieto, G. Aleph; Cotman, Carl W.

2017-01-01

Cytokines play crucial roles in the communication between brain cells including neurons and glia, as well as in the brain-periphery interactions. In the brain, cytokines modulate long-term potentiation (LTP), a cellular correlate of memory. Whether cytokines regulate LTP by direct effects on neurons or by indirect mechanisms mediated by non-neuronal cells is poorly understood. Elucidating neuron-specific effects of cytokines has been challenging because most brain cells express cytokine receptors. Moreover, cytokines commonly increase the expression of multiple cytokines in their target cells, thus increasing the complexity of brain cytokine networks even after single-cytokine challenges. Here, we review evidence on both direct and indirect-mediated modulation of LTP by cytokines. We also describe novel approaches based on neuron- and synaptosome-enriched systems to identify cytokines able to directly modulate LTP, by targeting neurons and synapses. These approaches can test multiple samples in parallel, thus allowing the study of multiple cytokines simultaneously. Hence, a cytokine networks perspective coupled with neuron-specific analysis may contribute to delineation of maps of the modulation of LTP by cytokines. PMID:28377062

Long-term potentiation and memory processes in the psychological works of Sigmund Freud and in the formation of neuropsychiatric symptoms.

PubMed

Centonze, D; Siracusano, A; Calabresi, P; Bernardi, G

2005-01-01

Far from disproving the model of mind functioning proposed by psychoanalysis, the recent advances in neuropsychiatrical research confirmed the crucial ideas of Sigmund Freud. The hypothesis that the origin of mental illnesses lies in the impossibility for a subject to erase the long-term effects of a remote adverse event is in tune with the view that several psychiatric disturbances reflect the activation of aberrant unconscious memory processes. Freud's insights did not stop here, but went on to describe in an extremely precise manner the neural mechanisms of memory formation almost a century before the description of long-term synaptic potentiation.

The potential benefits of a new poliovirus vaccine for long-term poliovirus risk management.

PubMed

Duintjer Tebbens, Radboud J; Thompson, Kimberly M

2016-12-01

To estimate the incremental net benefits (INBs) of a hypothetical ideal vaccine with all of the advantages and no disadvantages of existing oral and inactivated poliovirus vaccines compared with current vaccines available for future outbreak response. INB estimates based on expected costs and polio cases from an existing global model of long-term poliovirus risk management. Excluding the development costs, an ideal poliovirus vaccine could offer expected INBs of US$1.6 billion. The ideal vaccine yields small benefits in most realizations of long-term risks, but great benefits in low-probability-high-consequence realizations. New poliovirus vaccines may offer valuable insurance against long-term poliovirus risks and new vaccine development efforts should continue as the world gathers more evidence about polio endgame risks.

Short-term and long-term plasticity interaction in human primary motor cortex.

PubMed

Iezzi, Ennio; Suppa, Antonio; Conte, Antonella; Li Voti, Pietro; Bologna, Matteo; Berardelli, Alfredo

2011-05-01

Repetitive transcranial magnetic stimulation (rTMS) over primary motor cortex (M1) elicits changes in motor evoked potential (MEP) size thought to reflect short- and long-term forms of synaptic plasticity, resembling short-term potentiation (STP) and long-term potentiation/depression (LTP/LTD) observed in animal experiments. We designed this study in healthy humans to investigate whether STP as elicited by 5-Hz rTMS interferes with LTP/LTD-like plasticity induced by intermittent and continuous theta-burst stimulation (iTBS and cTBS). The effects induced by 5-Hz rTMS and iTBS/cTBS were indexed as changes in MEP size. We separately evaluated changes induced by 5-Hz rTMS, iTBS and cTBS applied alone and those induced by iTBS and cTBS delivered after priming 5-Hz rTMS. Interactions between 5-Hz rTMS and iTBS/cTBS were investigated under several experimental conditions by delivering 5-Hz rTMS at suprathreshold and subthreshold intensity, allowing 1 and 5 min intervals to elapse between 5-Hz rTMS and TBS, and delivering one and ten 5-Hz rTMS trains. We also investigated whether 5-Hz rTMS induces changes in intracortical excitability tested with paired-pulse transcranial magnetic stimulation. When given alone, 5-Hz rTMS induced short-lasting and iTBS/cTBS induced long-lasting changes in MEP amplitudes. When M1 was primed with 10 suprathreshold 5-Hz rTMS trains at 1 min before iTBS or cTBS, the iTBS/cTBS-induced after-effects disappeared. The 5-Hz rTMS left intracortical excitability unchanged. We suggest that STP elicited by suprathreshold 5-Hz rTMS abolishes iTBS/cTBS-induced LTP/LTD-like plasticity through non-homeostatic metaplasticity mechanisms. Our study provides new information on interactions between short-term and long-term rTMS-induced plasticity in human M1. © 2011 The Authors. European Journal of Neuroscience © 2011 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

Disparities in long-term care: building equity into market-based reforms.

PubMed

Konetzka, R Tamara; Werner, Rachel M

2009-10-01

A growing body of evidence documents pervasive racial, ethnic, and class disparities in long-term care in the United States. At the same time, major quality improvement initiatives are being implemented that rely on market-based incentives, many of which may have the unintended consequence of exacerbating disparities. We review existing evidence on disparities in the use and quality of long-term care services, analyze current market-based policy initiatives in terms of their potential to ameliorate or exacerbate these disparities, and suggest policies and policy modifications that may help decrease disparities. We find that racial disparities in the use of formal long-term care have decreased over time. Disparities in quality of care are more consistently documented and appear to be related to racial and socioeconomic segregation of long-term care facilities as opposed to within-provider discrimination. Market-based incentives policies should explicitly incorporate the goal of mitigating the potential unintended consequence of increased disparities.

In vivo wireless biodiagnosis system for long-term bioactivity monitoring network

NASA Astrophysics Data System (ADS)

Chen, Chun-Kuang; Wu, Wen-Jong; Yu, Shih-An; Huang, Jhen-Gang; Lin, Yun-Han; Chen, Yih-Fan; Jin, Ming-Hui; Wen, Chih-Min; Kao, Cheng-Yan; Lin, Shi-Ming; Lu, Shey-Shi; Lin, Chii-Wann; Yen, Jia-Yush; Jaw, Fu-Shan; Chen, Chi-An; Liao, Fang-Jen; Chiu, Nan-Fu; Chien, Chia-Nan; Lee, Chih-Kung

2004-07-01

Attempts to develop a Wireless Health Advanced Mobile Bio-diagnostic System (abbreviated as WHAM-BioS) have arisen from the need to monitor the health status of patients under long-term care programs. The proposed WHAM-BioS as presented here was developed by integrating various technologies: nano/MEMS technology, biotechnology, network/communication technology, and information technology. The biochips proposed not only detect certain diseases but will also report any abnormal status readings on the patient to the medical personnel immediately through the network system. Since long-term home care is typically involved, the parameters monitored must be analyzed and traced continuously over a long period of time. To minimize the intrusion to the patients, a wireless sensor embedded within a wireless network is highly recommended. To facilitate the widest possible use of various biochips, a smart sensor node concept was implemented. More specifically, various technologies and components such as built-in micro power generators, energy storage devices, initialization processes, no-waste bio-detection methodologies, embedded controllers, wireless warning signal transmissions, and power/data management were merged and integrated to create this novel technology. The design methodologies and the implementation schemes are detailed. Potential expansions of this newly developed technology to other applications regimes will be presented as well.

Living Gerontology: Providing Long-Distance, Long-term Care.

PubMed

Kivnick, Helen Q

2017-02-01

My own living and working through normative family transitions of parent care (as both a professional gerontologist and an intergenerational family member) facilitated five important kinds of growth: (a) providing parent care with optimal integrity; (b) understanding, elaborating, and teaching life-cycle theory with increasing depth; (c) using this theory to enrich practice approaches to long-term care; (d) identifying valuable new research directions; and (e) creating a multidimensional professional life that furthers theoretical development and identifies practice principles that promote individual, familial, and societal experiences of a "good old age." This reflective essay addresses these different kinds of growth, as they emerged from and contribute to the ever-developing gerontological domains of theory and practice. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Inflammatory markers in relation to long-term air pollution.

PubMed

Mostafavi, Nahid; Vlaanderen, Jelle; Chadeau-Hyam, Marc; Beelen, Rob; Modig, Lars; Palli, Domenico; Bergdahl, Ingvar A; Vineis, Paolo; Hoek, Gerard; Kyrtopoulos, Soterios Α; Vermeulen, Roel

2015-08-01

Long-term exposure to ambient air pollution can lead to chronic health effects such as cancer, cardiovascular and respiratory disease. Systemic inflammation has been hypothesized as a putative biological mechanism contributing to these adverse health effects. We evaluated the effect of long-term exposure to air pollution on blood markers of systemic inflammation. We measured a panel of 28 inflammatory markers in peripheral blood samples from 587 individuals that were biobanked as part of a prospective study. Participants were from Varese and Turin (Italy) and Umea (Sweden). Long-term air pollution estimates of nitrogen oxides (NOx) were available from the European Study of Cohorts for Air Pollution Effects (ESCAPE). Linear mixed models adjusted for potential confounders were applied to assess the association between NOx and the markers of inflammation. Long-term exposure to NOx was associated with decreased levels of interleukin (IL)-2, IL-8, IL-10 and tumor necrosis factor-α in Italy, but not in Sweden. NOx exposure levels were considerably lower in Sweden than in Italy (Sweden: median (5th, 95th percentiles) 6.65 μg/m(3) (4.8, 19.7); Italy: median (5th, 95th percentiles) 94.2 μg/m(3) (7.8, 124.5)). Combining data from Italy and Sweden we only observed a significant association between long-term exposure to NOx and decreased levels of circulating IL-8. We observed some indication for perturbations in the inflammatory markers due to long-term exposure to NOx. Effects were stronger in Italy than in Sweden, potentially reflecting the difference in air pollution levels between the two cohorts. Copyright © 2015 Elsevier Ltd. All rights reserved.

The metabotropic glutamate receptor mGluR3 is critically required for hippocampal long-term depression and modulates long-term potentiation in the dentate gyrus of freely moving rats.

PubMed

Pöschel, Beatrice; Wroblewska, Barbara; Heinemann, Uwe; Manahan-Vaughan, Denise

2005-09-01

Group II metabotropic glutamate receptors (mGluRs) play an important role in the regulation of hippocampal synaptic plasticity in vivo: long-term potentiation (LTP) is inhibited and long-term depression (LTD) is enhanced by activation of these receptors. The contribution, in vivo, of the individual group II mGluR subtypes has not been characterized. We analysed the involvement of the subtype mGluR3 in LTD and LTP. Rats were implanted with electrodes to enable chronic measurement of evoked potentials from medial perforant path-dentate gyrus synapses. Neither the selective mGluR3 agonist, N-acetylaspartylglutamate (NAAG), nor the antagonist beta-NAAG, given intracerebrally, affected basal synaptic transmission. beta-NAAG significantly inhibited LTD expression. NAAG exhibited transient inhibitory effects on the intermediate phase of LTD. Whereas NAAG altered paired-pulse responses, beta-NAAG had no effect, suggesting that antagonism of mGluR3 prevents LTD via a postsynaptic mechanism, whereas agonist activation of mGluR3 modulates LTD at a presynaptic locus. NAAG impaired the expression of LTP, whereas beta-NAAG had no effect. NAAG effects on LTP were blocked by EGLU, a selective group II mGluR antagonist. Our data suggest an essential role for mGluR3 in LTD, and a modulatory role for mGluR3 in LTP, with effects being mediated by distinct pre- and post-synaptic loci.

Contextual consistency facilitates long-term memory of perceptual detail in barely seen images.

PubMed

Gronau, Nurit; Shachar, Meytal

2015-08-01

It is long known that contextual information affects memory for an object's identity (e.g., its basic level category), yet it is unclear whether schematic knowledge additionally enhances memory for the precise visual appearance of an item. Here we investigated memory for visual detail of merely glimpsed objects. Participants viewed pairs of contextually related and unrelated stimuli, presented for an extremely brief duration (24 ms, masked). They then performed a forced-choice memory-recognition test for the precise perceptual appearance of 1 of 2 objects within each pair (i.e., the "memory-target" item). In 3 experiments, we show that memory-target stimuli originally appearing within contextually related pairs are remembered better than targets appearing within unrelated pairs. These effects are obtained whether the target is presented at test with its counterpart pair object (i.e., when reiterating the original context at encoding) or whether the target is presented alone, implying that the contextual consistency effects are mediated predominantly by processes occurring during stimulus encoding, rather than during stimulus retrieval. Furthermore, visual detail encoding is improved whether object relations involve implied action or not, suggesting that, contrary to some prior suggestions, action is not a necessary component for object-to-object associative "grouping" processes. Our findings suggest that during a brief glimpse, but not under long viewing conditions, contextual associations may play a critical role in reducing stimulus competition for attention selection and in facilitating rapid encoding of sensory details. Theoretical implications with respect to classic frame theories are discussed. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

The potential use of diisononyl phthalate metabolites hair as biomarkers to assess long-term exposure demonstrated by a rat model.

PubMed

Hsu, Jen-Yi; Ho, Hsin-Hui; Liao, Pao-Chi

2015-01-01

Diisononyl phthalate (DINP) is a widely used industrial plasticizer. People come into contact with this chemical by using plastic products made with it. Human health can be adversely affected by long-term DINP exposure. However, because the body rapidly excretes DINP metabolites, the use of single-point urine analysis to assess long-term exposure may produce inconsistent results in epidemiologic studies. Hair analysis has a useful place in biomonitoring, particularly in estimating long-term or historical exposure for some chemicals. Several studies have reported using hair analysis to assess the concentrations of heavy metals, drugs and organic pollutants in humans. As a biomarker, DINP metabolites were measured in rat hair in animal experiments to evaluated long-term exposure to DINP. In addition, we evaluated the correlation between the levels of DINP metabolites in hair and in urine. The levels of DINP metabolites in rat hair were significantly higher in the exposure group, relative to the control group (p<0.05). DINP metabolites had a positive correlation with increasing administered dose. Significant positive correlations for MINP, MOINP and MHINP were found between hair and urine (r=0.86, r=0.79 and r=0.74, respectively, p<0.05). Several metabolites in urine showed earlier saturation than in hair. In this report, we detected eight metabolites in hair and demonstrate that hair analysis has potential applications in the assessment of long-term exposure to DINP. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Role of Long-Term Memory in a Test of Visual Working Memory: Proactive Facilitation but No Proactive Interference

ERIC Educational Resources Information Center

Oberauer, Klaus; Awh, Edward; Sutterer, David W.

2017-01-01

We report 4 experiments examining whether associations in visual working memory are subject to proactive interference from long-term memory (LTM). Following a long-term learning phase in which participants learned the colors of 120 unique objects, a working memory (WM) test was administered in which participants recalled the precise colors of 3…

Influence of visual experience on developmental shift from long-term depression to long-term potentiation in the rat medial vestibular nuclei.

PubMed

Grassi, Silvarosa; Dieni, Cristina; Frondaroli, Adele; Pettorossi, Vito Enrico

2004-11-01

The influence of visual experience deprivation on changes in synaptic plasticity during postnatal development was studied in the ventral part of the rat medial vestibular nuclei (vMVN). We analysed the differences in the occurrence, expressed as a percentage, of long-term depression (LTD) and long-term potentiation (LTP) induced by high frequency stimulation (HFS) of the primary vestibular afferents in rats reared in the light (LR) and those in the dark (DR). In LR rats, HFS only induced LTD in the early stages of development, but the occurrence of LTD progressively decreased to zero before their eyes opened, while that of LTP enhanced from zero to about 50%. Once the rats' eyes had opened, LTD was no longer inducible while LTP occurrence gradually reached the normal adult value (70%). In DR rats, a similar shift from LTD to LTP was observed before their eyes opened, showing only a slightly slower LTD decay and LTP growth, and the LTD annulment was delayed by 1 day. By contrast, the time courses of LTD and LTP development in DR and LR rats showed remarkable differences following eye opening. In fact, LTD occurrence increased to about 50% in a short period of time and remained high until the adult stage. In addition, the occurrence of LTP slowly decreased to less than 20%. The effect of light-deprivation was reversible, since the exposure of DR rats to light, 5 days after eye opening, caused a sudden disappearance of LTD and a partial recover of LTP occurrence. In addition, we observed that a week of light deprivation in LR adult rats did not affect the normal adult LTP occurrence. These results provide evidence that in a critical period of development visual input plays a crucial role in shaping synaptic plasticity of the vMVN, and suggest that the visual guided shift from LTD to LTP during development may be necessary to refine and consolidate vestibular circuitry.

Influence of visual experience on developmental shift from long-term depression to long-term potentiation in the rat medial vestibular nuclei

PubMed Central

Grassi, Silvarosa; Dieni, Cristina; Frondaroli, Adele; Pettorossi, Vito Enrico

2004-01-01

The influence of visual experience deprivation on changes in synaptic plasticity during postnatal development was studied in the ventral part of the rat medial vestibular nuclei (vMVN). We analysed the differences in the occurrence, expressed as a percentage, of long-term depression (LTD) and long-term potentiation (LTP) induced by high frequency stimulation (HFS) of the primary vestibular afferents in rats reared in the light (LR) and those in the dark (DR). In LR rats, HFS only induced LTD in the early stages of development, but the occurrence of LTD progressively decreased to zero before their eyes opened, while that of LTP enhanced from zero to about 50%. Once the rats' eyes had opened, LTD was no longer inducible while LTP occurrence gradually reached the normal adult value (70%). In DR rats, a similar shift from LTD to LTP was observed before their eyes opened, showing only a slightly slower LTD decay and LTP growth, and the LTD annulment was delayed by 1 day. By contrast, the time courses of LTD and LTP development in DR and LR rats showed remarkable differences following eye opening. In fact, LTD occurrence increased to about 50% in a short period of time and remained high until the adult stage. In addition, the occurrence of LTP slowly decreased to less than 20%. The effect of light-deprivation was reversible, since the exposure of DR rats to light, 5 days after eye opening, caused a sudden disappearance of LTD and a partial recover of LTP occurrence. In addition, we observed that a week of light deprivation in LR adult rats did not affect the normal adult LTP occurrence. These results provide evidence that in a critical period of development visual input plays a crucial role in shaping synaptic plasticity of the vMVN, and suggest that the visual guided shift from LTD to LTP during development may be necessary to refine and consolidate vestibular circuitry. PMID:15331680

Amyloid-β Peptide Is Needed for cGMP-Induced Long-Term Potentiation and Memory.

PubMed

Palmeri, Agostino; Ricciarelli, Roberta; Gulisano, Walter; Rivera, Daniela; Rebosio, Claudia; Calcagno, Elisa; Tropea, Maria Rosaria; Conti, Silvia; Das, Utpal; Roy, Subhojit; Pronzato, Maria Adelaide; Arancio, Ottavio; Fedele, Ernesto; Puzzo, Daniela

2017-07-19

High levels of amyloid-β peptide (Aβ) have been related to Alzheimer's disease pathogenesis. However, in the healthy brain, low physiologically relevant concentrations of Aβ are necessary for long-term potentiation (LTP) and memory. Because cGMP plays a key role in these processes, here we investigated whether the cyclic nucleotide cGMP influences Aβ levels and function during LTP and memory. We demonstrate that the increase of cGMP levels by the phosphodiesterase-5 inhibitors sildenafil and vardenafil induces a parallel release of Aβ due to a change in the approximation of amyloid precursor protein (APP) and the β-site APP cleaving enzyme 1. Moreover, electrophysiological and behavioral studies performed on animals of both sexes showed that blocking Aβ function, by using anti-murine Aβ antibodies or APP knock-out mice, prevents the cGMP-dependent enhancement of LTP and memory. Our data suggest that cGMP positively regulates Aβ levels in the healthy brain which, in turn, boosts synaptic plasticity and memory. SIGNIFICANCE STATEMENT Amyloid-β (Aβ) is a key pathogenetic factor in Alzheimer's disease. However, low concentrations of endogenous Aβ, mimicking levels of the peptide in the healthy brain, enhance hippocampal long-term potentiation (LTP) and memory. Because the second messenger cGMP exerts a central role in LTP mechanisms, here we studied whether cGMP affects Aβ levels and function during LTP. We show that cGMP enhances Aβ production by increasing the APP/BACE-1 convergence in endolysosomal compartments. Moreover, the cGMP-induced enhancement of LTP and memory was disrupted by blockade of Aβ, suggesting that the physiological effect of the cyclic nucleotide on LTP and memory is dependent upon Aβ. Copyright © 2017 the authors 0270-6474/17/376926-12$15.00/0.

A Short-Term Biological Indicator for Long-Term Kidney Damage after Radionuclide Therapy in Mice

PubMed Central

Pellegrini, Giovanni; Siwowska, Klaudia; Haller, Stephanie; Antoine, Daniel J.; Schibli, Roger; Kipar, Anja; Müller, Cristina

2017-01-01

Folate receptor (FR)-targeted radionuclide therapy using folate radioconjugates is of interest due to the expression of the FR in a variety of tumor types. The high renal accumulation of radiofolates presents, however, a risk of radionephropathy. A potential option to address this challenge would be to use radioprotectants, such as amifostine. Methods for early detection of kidney damage that—in this case—cannot be predicted based on dose estimations, would facilitate the development of novel therapies. The aim of this study was, therefore, to assess potentially changing levels of plasma and urine biomarkers and to determine DNA damage at an early stage after radiofolate application. The identification of an early indicator for renal damage in mice would be useful since histological changes become apparent only several months after treatment. Mice were injected with different quantities of 177Lu-folate (10 MBq, 20 MBq and 30 MBq), resulting in mean absorbed kidney doses of ~23 Gy, ~46 Gy and ~69 Gy, respectively, followed by euthanasia two weeks (>85% of the mean renal radiation dose absorbed) or three months later. Whereas all investigated biomarkers remained unchanged, the number of γ-H2AX-positive nuclei in the renal cortex showed an evident dose-dependent increase as compared to control values two weeks after treatment. Comparison with the extent of kidney injury determined by histological changes five to eight months after administration of the same 177Lu-folate activities suggested that the quantitative assessment of double-strand breaks can be used as a biological indicator for long-term radiation effects in the kidneys. This method may, thus, enable faster assessment of radiopharmaceuticals and protective measures by preventing logistically challenging long-term investigations to detect kidney damage. PMID:28635637

Drug-nutrient interactions in three long-term-care facilities.

PubMed

Lewis, C W; Frongillo, E A; Roe, D A

1995-03-01

To assess the risk of drug-nutrient interactions (DNIs) in three long-term-care facilities. Retrospective audit of charts. Three long-term-care facilities in central New York State. Fifty-three patients selected randomly from each facility. Data were collected from the medical record of each patient for a period of 6 months. A computerized algorithm was used to assess the risk for DNIs. Mean drug use, most frequently consumed drugs, incidence of potential DNIs, and the most commonly observed potential DNIs are reported. In facilities A, B, and C, respectively, patients consumed a mean of 4.86, 4.04, and 5.27 drugs per patient per month and were at risk for a mean of 1.43, 2.69, and 1.43 potential DNIs per patient per month. The most commonly observed potential DNIs were gastrointestinal interactions affecting drug bioavailability and interactions affecting electrolyte status. Patients in long-term-care facilities, who are primarily elderly and chronically ill and who consume multiple medications, are at notable risk for certain DNIs. Efforts need to be made to ensure appropriate pharmacologic and nutrition therapies as well as adequate and timely monitoring of patients in these facilities. Dietitians can play an important role in training other health professionals and in designing policies to prevent DNIs.

Long-Term Environmental Research Programs - Evolving Capacity for Discovery

NASA Astrophysics Data System (ADS)

Swanson, F. J.

2008-12-01

Long-term forestry, watershed, and ecological research sites have become critical, productive nodes for environmental science research and in some cases for work in the social sciences and humanities. The Forest Service's century-old Experimental Forests and Ranges and the National Science Foundation's 28- year-old Long-Term Ecological Research program have been remarkably productive in both basic and applied sciences, including characterization of acid rain and old-growth ecosystems and development of forest, watershed, and range management systems for commercial and other land use objectives. A review of recent developments suggests steps to enhance the function of collections of long-term research sites as interactive science networks. The programs at these sites have evolved greatly, especially over the past few decades, as the questions addressed, disciplines engaged, and degree of science integration have grown. This is well displayed by small, experimental watershed studies, which first were used for applied hydrology studies then more fundamental biogeochemical studies and now examination of complex ecosystem processes; all capitalizing on the legacy of intensive studies and environmental monitoring spanning decades. In very modest ways these collections of initially independent sites have functioned increasingly as integrated research networks addressing inter-site questions by using common experimental designs, being part of a single experiment, and examining long-term data in a common analytical framework. The network aspects include data sharing via publicly-accessible data-harvester systems for climate and streamflow data. The layering of one research or environmental monitoring network upon another facilitates synergies. Changing climate and atmospheric chemistry highlight a need to use these networks as continental-scale observatory systems for assessing the impacts of environmental change on ecological services. To better capitalize on long-term

Neurogranin restores amyloid β-mediated synaptic transmission and long-term potentiation deficits.

PubMed

Kaleka, Kanwardeep Singh; Gerges, Nashaat Z

2016-03-01

Amyloid β (Aβ) is widely considered one of the early causes of cognitive deficits observed in Alzheimer's disease. Many of the deficits caused by Aβ are attributed to its disruption of synaptic function represented by its blockade of long-term potentiation (LTP) and its induction of synaptic depression. Identifying pathways that reverse these synaptic deficits may open the door to new therapeutic targets. In this study, we explored the possibility that Neurogranin (Ng)-a postsynaptic calmodulin (CaM) targeting protein that enhances synaptic function-may rescue Aβ-mediated deficits in synaptic function. Our results show that Ng is able to reverse synaptic depression and LTP deficits induced by Aβ. Furthermore, Ng's restoration of synaptic transmission is through the insertion of GluA1-containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid glutamate receptors (AMPARs). These restorative effects of Ng are dependent on the interaction of Ng and CaM and CaM-dependent activation of CaMKII. Overall, this study identifies a novel mechanism to rescue synaptic deficits induced by Aβ oligomers. It also suggests Ng and CaM signaling as potential therapeutic targets for Alzheimer's disease as well as important tools to further explore the pathophysiology underlying the disease. Copyright © 2015 Elsevier Inc. All rights reserved.

Long-term Morbidity of Testicular Cancer Treatment.

PubMed

Fung, Chunkit; Fossa, Sophie D; Williams, Annalynn; Travis, Lois B

2015-08-01

Second malignant neoplasms, cardiovascular disease, neurotoxicity and ototoxicity, pulmonary complications, hypogonadism, and nephrotoxicity are potentially life-threatening long-term complications of testicular cancer and its therapy. This article describes the pathogenesis, risks, and management of these late effects experienced by long-term testicular cancer survivors, who are defined as individuals who are disease free 5 years or more after primary treatment. Testicular cancer survivors should follow applicable national guidelines for cancer screening and management of cardiovascular disease risk factors. In addition, health care providers should capitalize on the time of cancer diagnosis as a teachable moment to introduce and promote lifestyle changes. Copyright © 2015 Elsevier Inc. All rights reserved.

Long-Term Care Financing: Lessons From France

PubMed Central

Doty, Pamela; Nadash, Pamela; Racco, Nathalie

2015-01-01

Context An aging population leads to a growing demand for long-term services and supports (LTSS). In 2002, France introduced universal, income-adjusted, public long-term care coverage for adults 60 and older, whereas the United States funds means-tested benefits only. Both countries have private long-term care insurance (LTCI) markets: American policies create alternatives to out-of-pocket spending and protect purchasers from relying on Medicaid. Sales, however, have stagnated, and the market's viability is uncertain. In France, private LTCI supplements public coverage, and sales are growing, although its potential to alleviate the long-term care financing problem is unclear. We explore whether France's very different approach to structuring public and private financing for long-term care could inform the United States’ long-term care financing reform efforts. Methods We consulted insurance experts and conducted a detailed review of public reports, academic studies, and other documents to understand the public and private LTCI systems in France, their advantages and disadvantages, and the factors affecting their development. Findings France provides universal public coverage for paid assistance with functional dependency for people 60 and older. Benefits are steeply income adjusted and amounts are low. Nevertheless, expenditures have exceeded projections, burdening local governments. Private supplemental insurance covers 11% of French, mostly middle-income adults (versus 3% of Americans 18 and older). Whether policyholders will maintain employer-sponsored coverage after retirement is not known. The government's interest in pursuing an explicit public/private partnership has waned under President François Hollande, a centrist socialist, in contrast to the previous center-right leader, President Nicolas Sarkozy, thereby reducing the prospects of a coordinated public/private strategy. Conclusions American private insurers are showing increasing interest in long-term

Electrical high-frequency stimulation of the human thoracolumbar fascia evokes long-term potentiation-like pain amplification.

PubMed

Schilder, Andreas; Magerl, Walter; Hoheisel, Ulrich; Klein, Thomas; Treede, Rolf-Detlef

2016-10-01

Nociceptive long-term potentiation, a use dependent increase in synaptic efficacy in the dorsal horn of the spinal cord is thought to contribute to the development of persistent pain states. So far, no study has analyzed the effects of high-frequency stimulation (HFS) of afferents from deep tissues (muscle and fascia) on pain perception in the back in humans. In 16 healthy volunteers, the multifidus muscle and the overlying thoracolumbar fascia were stimulated with electrical high-frequency pulses (5 × 100 pulses at 100 Hz) through bipolar concentric needle electrodes placed at lumbar level (L3/L4). Electrical pain thresholds were lower (P < 0.001) and pain ratings were higher for fascia compared with muscle stimulation (P < 0.05). For both tissues, pain ratings increased significantly across the five 100 Hz trains (from 15 to 22 numerical rating scale for fascia, from 8 to 12 numerical rating scale for muscle; both P < 0.01). Fascia HFS increased fascia pain ratings 2.17 times compared with the unconditioned control site (P < 0.001), but had no significant effect on pain sensitivity of the muscle. The HFS in muscle had no significant effect on muscle pain, but decreased pain sensitivity of the overlying fascia by 20% (P < 0.05). In additional experiments using the same electrodes and followed over >60 minutes post-HFS, potentiation by fascia HFS was similar to that of skin HFS. These findings show that the spinal input from the fascia can induce long-term changes in pain sensitivity for at least 60 minutes making it a candidate potentially contributing to nonspecific low back pain.

D-Serine rescues the deficits of hippocampal long-term potentiation and learning and memory induced by sodium fluoroacetate.

PubMed

Han, Huili; Peng, Yan; Dong, Zhifang

2015-06-01

It is well known that bidirectional glia-neuron interactions play important roles in the neurophysiological and neuropathological processes. It is reported that impairing glial functions with sodium fluoroacetate (FAC) impaired hippocampal long-term depression (LTD) and spatial memory retrieval. However, it remains unknown whether FAC impairs hippocampal long-term potentiation (LTP) and learning and/or memory, and if so, whether pharmacological treatment with exogenous d-serine can recuse the impairment. Here, we reported that systemic administration of FAC (3mg/kg, i.p.) before training resulted in dramatic impairments of spatial learning and memory in water maze and fear memory in contextual fear conditioning. Furthermore, the behavioral deficits were accompanied by impaired LTP induction in the hippocampal CA1 area of brain slices. More importantly, exogenous d-serine treatment succeeded in recusing the deficits of hippocampal LTP and learning and memory induced by FAC. Together, these results suggest that astrocytic d-serine may be essential for hippocampal synaptic plasticity and memory, and that alteration of its levels may be relevant to the induction and potentially treatment of psychiatric and neurological disorders. Copyright © 2015 Elsevier Inc. All rights reserved.

Long-term repetition priming with symmetrical polygons and words.

PubMed

Kersteen-Tucker, Z

1991-01-01

In two different tasks, subjects were asked to make lexical decisions (word or nonword) and symmetry judgments (symmetrical or nonsymmetrical) about two-dimensional polygons. In both tasks, every stimulus was repeated at one of four lags (0, 1, 4, or 8 items interposed between the first and second stimulus presentations). This paradigm, known as repetition priming, revealed comparable short-term priming (Lag 0) and long-term priming (Lags 1, 4, and 8) both for symmetrical polygons and for words. A shorter term component (Lags 0 and 1) of priming was observed for nonwords, and only very short-term priming (Lag 0) was observed for nonsymmetrical polygons. These results indicate that response facilitation accruing from repeated exposure can be observed for stimuli that have no preexisting memory representations and suggest that perceptual factors contribute to repetition-priming effects.

Locus Coeruleus Stimulation Facilitates Long-Term Depression in the Dentate Gyrus That Requires Activation of β-Adrenergic Receptors

PubMed Central

Hansen, Niels; Manahan-Vaughan, Denise

2015-01-01

Synaptic plasticity comprises a cellular mechanism through which the hippocampus most likely enables memory formation. Neuromodulation, related to arousal, is a key aspect in information storage. The activation of locus coeruleus (LC) neurons by novel experience leads to noradrenaline release in the hippocampus at the level of the dentate gyrus (DG). We explored whether synaptic plasticity in the DG is influenced by activation of the LC via electrical stimulation. Coupling of test-pulses that evoked stable basal synaptic transmission in the DG with stimulation of the LC induced β-adrenoreceptor-dependent long-term depression (LTD) at perforant path–DG synapses in adult rats. Furthermore, persistent LTD (>24 h) induced by perforant path stimulation also required activation of β-adrenergic receptors: Whereas a β-adrenergic receptor antagonist (propranolol) prevented, an agonist (isoproterenol) strengthened the persistence of LTD for over 24 h. These findings support the hypothesis that persistent LTD in the DG is modulated by β-adrenergic receptors. Furthermore, LC activation potently facilitates DG LTD. This suggests in turn that synaptic plasticity in the DG is tightly regulated by activity in the noradrenergic system. This may reflect the role of the LC in selecting salient information for subsequent synaptic processing in the hippocampus. PMID:24464942

Cytokines and cytokine networks target neurons to modulate long-term potentiation.

PubMed

Prieto, G Aleph; Cotman, Carl W

2017-04-01

Cytokines play crucial roles in the communication between brain cells including neurons and glia, as well as in the brain-periphery interactions. In the brain, cytokines modulate long-term potentiation (LTP), a cellular correlate of memory. Whether cytokines regulate LTP by direct effects on neurons or by indirect mechanisms mediated by non-neuronal cells is poorly understood. Elucidating neuron-specific effects of cytokines has been challenging because most brain cells express cytokine receptors. Moreover, cytokines commonly increase the expression of multiple cytokines in their target cells, thus increasing the complexity of brain cytokine networks even after single-cytokine challenges. Here, we review evidence on both direct and indirect-mediated modulation of LTP by cytokines. We also describe novel approaches based on neuron- and synaptosome-enriched systems to identify cytokines able to directly modulate LTP, by targeting neurons and synapses. These approaches can test multiple samples in parallel, thus allowing the study of multiple cytokines simultaneously. Hence, a cytokine networks perspective coupled with neuron-specific analysis may contribute to delineation of maps of the modulation of LTP by cytokines. Copyright © 2017 Elsevier Ltd. All rights reserved.

Long-term Ecosystem Experiments, Data Assimilation, and Meta-Analysis

NASA Astrophysics Data System (ADS)

Hungate, B. A.; Van Groenigen, K. J.; Osenberg, C. W.; van Gestel, N.

2015-12-01

Land ecosystems affect climate and the atmosphere, and climate and atmospheric change affects ecosystems. Syntheses of ecosystem experiments investigating their responses to environmental change holds promise for understanding how to model these interactions, and thereby gain insight into Earth's future biosphere, atmosphere, and climate. Long-term experiments examining ecosystem responses are thought to be especially important in this effort, for their potential to reveal cumulative and progressive effects, subtle effects initially undetectable experimentally, but manifest more clearly over time, often with stronger implications for modeled responses than the more dramatic, short-term experimental responses. Here, we present new analyses of long-term experiments manipulating temperature, CO2 concentration, and precipitation, testing the general hypothesis that there are common temporal patterns of responses that reveal general biogeochemical characterizing ecosystem responses to these environmental changes. For example, we show that increased carbon input with elevated CO2 stimulates emissions of nitrous oxide and methane, important greenhouse gases, and that effects show no signs of diminishing over the duration of experiments that have documented responses. At the same time, we show that the temporal resolution for this response is limited, pointing to a potential limitation in the ability of experiments to address clearly long-term hypotheses. We also show that warming tends to have limited cumulative effects on total soil carbon stocks in long-term experiments, and explore the mechanisms underlying this response. Finally, we discuss the implications of these findings for models used to simulate long-term ecosystem responses to these environmental forcings, as well as the implications of these findings for the next generation of terrestrial ecosystem experiments.

Distinct Roles of PKCι/λ and PKMζ in the Initiation and Maintenance of Hippocampal Long-Term Potentiation and Memory.

PubMed

Wang, Shaoli; Sheng, Tao; Ren, Siqiang; Tian, Tian; Lu, Wei

2016-08-16

PKMζ has been proposed to be essential for maintenance of long-term potentiation (LTP) and long-term memory (LTM). However, recent data from PKMζ-knockout mice has called this role into question. Instead, the other atypical isoform, protein kinase C iota/lambda (PKCι/λ), has emerged as a potential alternative player. Therefore, the nature of the "memory molecule" maintaining learned information remains uncertain. Here, we report knockdown (KD) of PKCι/λ and PKMζ in the dorsal hippocampus and find deficits in early expression and late maintenance, respectively, during both LTP and hippocampus-dependent LTM. Sequential increases in the active form of PKCι/λ and PKMζ are detected during LTP or fear conditioning. Importantly, PKMζ, but not PKCι/λ, KD disrupts previously established LTM. Thus, PKCι/λ and PKMζ have distinct functions in LTP and memory, with PKMζ playing a specific role in memory maintenance. This relaying pattern may represent a precise molecular mechanism by which atypical PKCs regulate the different stages of memory. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Ibogaine signals addiction genes and methamphetamine alteration of long-term potentiation.

PubMed

Onaivi, Emmanuel S; Ali, Syed F; Chirwa, Sanika S; Zwiller, Jean; Thiriet, Nathalie; Akinshola, B Emmanuel; Ishiguro, Hiroki

2002-06-01

The mapping of the human genetic code will enable us to identify potential gene products involved in human addictions and diseases that have hereditary components. Thus, large-scale, parallel gene-expression studies, made possible by advances in microarray technologies, have shown insights into the connection between specific genes, or sets of genes, and human diseases. The compulsive use of addictive substances despite adverse consequences continues to affect society, and the science underlying these addictions in general is intensively studied. Pharmacological treatment of drug and alcohol addiction has largely been disappointing, and new therapeutic targets and hypotheses are needed. As the usefulness of the pharmacotherapy of addiction has been limited, an emerging potential, yet controversial, therapeutic agent is the natural alkaloid ibogaine. We have continued to investigate programs of gene expression and the putative signaling molecules used by psychostimulants such as amphetamine in in vivo and in vitro models. Our work and that of others reveal that complex but defined signal transduction pathways are associated with psychostimulant administration and that there is broad-spectrum regulation of these signals by ibogaine. We report that the actions of methamphetamine were similar to those of cocaine, including the propensity to alter long-term potentiation (LTP) in the hippocampus of the rat brain. This action suggests that there may be a "threshold" beyond which the excessive brain stimulation that probably occurs with compulsive psychostimulant use results in the occlusion of LTP. The influence of ibogaine on immediate early genes (IEGs) and other candidate genes possibly regulated by psychostimulants and other abused substances requires further evaluation in compulsive use, reward, relapse, tolerance, craving and withdrawal reactions. It is therefore tempting to suggest that ibogaine signals addiction gene products.

Effect of climate fluctuation on long-term vegetation dynamics in Carolina bay wetlands

Treesearch

Chrissa Stroh; Diane De Steven; Glenn Guntenspergen

2008-01-01

Carolina bays and similar depression wetlands of the U. S. Southeastern Coastal Plain have hydrologic regimes that are driven primarily by rainfall. Therefore, climate fluctuations such as drought cycles have the potential to shape long-term vegetation dynamics. Models suggest two potential long-term responses to hydrologic fluctuations, either cyclic change...

Subchronic MK-801 treatment and post-weaning social isolation in rats: differential effects on locomotor activity and hippocampal long-term potentiation.

PubMed

Ashby, Donovan M; Habib, Diala; Dringenberg, Hans C; Reynolds, James N; Beninger, Richard J

2010-09-01

Subchronic NMDA receptor antagonist treatment and post-weaning social isolation are two animal models of schizophrenia symptoms. However, behavioral and physiological changes following a combination of these two procedures have not been investigated. Thus, we examined effects of a novel, "double hit" model combining these two treatments, comparing them to standard models involving only NMDA antagonist treatment or social isolation. Male, Sprague-Dawley rats were either group-housed or maintained in social isolation (starting at postnatal day [PD] 21 and continuing throughout the study). Each housing condition was further subdivided into two groups, receiving either subchronic treatment with either saline or MK-801 (0.5mg/kg, i.p., 2xday for seven days starting at PD 56). Post-weaning social isolation increased locomotor activity (assessed at PD 70) in response to a novel environment and an acute amphetamine injection, while subchronic MK-801 increased only amphetamine induced locomotor activity. Subsequent electrophysiological experiments (under urethane anesthesia) assessing changes in plasticity of hippocampal synapses showed that subchronic MK-801 treatment resulted in an increase in long-term potentiation in area CA1 in response to high frequency stimulation of the contralateral CA3 area, while housing condition had no effect. No other changes in hippocampal electrophysiology (input-output curves, paired-pulse facilitation) were observed. These data are the first to demonstrate an enhancement in hippocampal long-term plasticity in vivo following subchronic MK-801 administration, an effect that may be related to the well-characterized changes in glutamatergic and GABAergic systems seen after subchronic NMDA receptor blockade. That lack of additive or synergistic effects in the "double hit model" suggests that combining isolation and subchronic MK-801 treatment does not necessarily produce greater behavioral or physiological dysfunction than that seen with either

Long-term use of short- and long-acting nitrates in stable angina pectoris.

PubMed

Kosmicki, Marek Antoni

2009-05-01

Long-acting nitrates are effective antianginal drugs during initial treatment. However, their therapeutic value is compromised by the rapid development of tolerance during sustained therapy, which means that their clinical efficacy is decreased during long-term use. Sublingual nitroglycerin (NTG), a short-acting nitrate, is suitable for the immediate relief of angina. In patients with stable angina treated with oral long-acting nitrates, NTG maintains its full anti-ischemic effect both after initial oral ingestion and after intermittent long-term oral administration. However, NTG attenuates this effect during continuous treatment, when tolerance to oral nitrates occurs, and this is called cross-tolerance. In stable angina long-acting nitrates are considered third-line therapy because a nitrate-free interval is required to avoid the development of tolerance. Nitrates vary in their potential to induce the development of tolerance. During long-lasting nitrate therapy, except pentaerythritol tetranitrate (PETN), one can observe the development of reactive oxygen species (ROS) inside the muscular cell of a vessel wall, and these bind with nitric oxide (NO). This leads to decreased NO activity, thus, nitrate tolerance. PETN has no tendency to form ROS, and therefore during long-term PETN therapy, there is probably no tolerance or cross-tolerance, as during treatment with other nitrates.

Randomized controlled trial evaluating the temporal effects of high-intensity exercise on learning, short-term and long-term memory, and prospective memory.

PubMed

Frith, Emily; Sng, Eveleen; Loprinzi, Paul D

2017-11-01

The broader purpose of this study was to examine the temporal effects of high-intensity exercise on learning, short-term and long-term retrospective memory and prospective memory. Among a sample of 88 young adult participants, 22 were randomized into one of four different groups: exercise before learning, control group, exercise during learning, and exercise after learning. The retrospective assessments (learning, short-term and long-term memory) were assessed using the Rey Auditory Verbal Learning Test. Long-term memory including a 20-min and 24-hr follow-up assessment. Prospective memory was assessed using a time-based procedure by having participants contact (via phone) the researchers at a follow-up time period. The exercise stimulus included a 15-min bout of progressive maximal exertion treadmill exercise. High-intensity exercise prior to memory encoding (vs. exercise during memory encoding or consolidation) was effective in enhancing long-term memory (for both 20-min and 24-h follow-up assessments). We did not observe a differential temporal effect of high-intensity exercise on short-term memory (immediate post-memory encoding), learning or prospective memory. The timing of high-intensity exercise may play an important role in facilitating long-term memory. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Persistent inhibition of hippocampal long-term potentiation in vivo by learned helplessness stress.

PubMed

Ryan, Benedict K; Vollmayr, Barbara; Klyubin, Igor; Gass, Peter; Rowan, Michael J

2010-06-01

The persistent cognitive disruptive effects of stress have been strongly implicated in the pathophysiology of depression and post-traumatic stress disorder. Here we examined factors influencing the time course of recovery from the inhibitory effect of acute inescapable stressors on the ability to induce long-term potentiation (LTP) in the dorsal hippocampus in vivo. We tested different forms of LTP, different stressors and different inbred strains of rats. Acute elevated platform stress completely, but transiently (<3 h), inhibited induction of both NMDA receptor-dependent LTP induced by a standard high frequency (200 Hz) conditioning stimulus and an additional LTP that required voltage-dependent Ca(2+) channel activation triggered by strong (400 Hz) conditioning stimulation. In contrast, acute inescapable footshock stress, used to study learned helplessness, inhibited LTP for at least 4 weeks. Contrary to expectations, there was no clear relationship between the ability of the footshock to trigger helpless behavior, a model of stress-induced depression, and the magnitude of LTP inhibition. Moreover, LTP did not appear to be affected by genetic susceptibility to learned helplessness, a model of genetic vulnerability to depression. This long-lasting synaptic plasticity disruption may underlie persistent impairment of hippocampus-dependent cognition by excessive acute inescapable stress.

Mechanisms of hippocampal long-term depression are required for memory enhancement by novelty exploration.

PubMed

Dong, Zhifang; Gong, Bo; Li, Hongjie; Bai, Yanrui; Wu, Xiaoyan; Huang, Yan; He, Wenting; Li, Tingyu; Wang, Yu Tian

2012-08-29

It is well known that novel environments can enhance learning and memory. However, the underlying mechanisms remain poorly understood. Here, we report that, in freely moving rats, novelty exploration facilitates the production of hippocampal CA1 long-term depression (LTD), a well characterized form of synaptic plasticity believed to be a cellular substrate of spatial learning, and thereby converts short-term memory (STM) into long-term memory (LTM) in an inhibitory avoidance learning procedure. Blocking the induction or the expression of CA1 LTD with two mechanistically and structurally distinct inhibitors prevents not only novelty acquisition but also the novelty exploration-promoted conversion of STM into LTM. Moreover, production of LTD with a strong electrical stimulation induction protocol or facilitation of hippocampal LTD by pharmacological inhibition of glutamate transporter activity mimics the behavioral effects of novelty exploration, sufficiently promoting the conversion of STM into LTM. Together, our findings suggest that induction of LTD may play an essential role not only in novelty acquisition but also in novelty-mediated memory enhancement.

A systematic review of potential long-term effects of sport-related concussion

PubMed Central

Gardner, Andrew J; Schneider, Kathryn J; Guskiewicz, Kevin M; Bailes, Julian; Cantu, Robert C; Castellani, Rudolph J; Turner, Michael; Jordan, Barry D; Randolph, Christopher; Dvořák, Jiří; Hayden, K. Alix; Tator, Charles H; McCrory, Paul; Iverson, Grant L

2017-01-01

Objective Systematic review of possible long-term effects of sports-related concussion in retired athletes. Data sources Ten electronic databases. Study selection Original research; incidence, risk factors or causation related to long-term mental health or neurological problems; individuals who have suffered a concussion; retired athletes as the subjects and possible long-term sequelae defined as >10 years after the injury. Data extraction Study population, exposure/outcome measures, clinical data, neurological examination findings, cognitive assessment, neuroimaging findings and neuropathology results. Risk of bias and level of evidence were evaluated by two authors. Results Following review of 3819 studies, 47 met inclusion criteria. Some former athletes have depression and cognitive deficits later in life, and there is an association between these deficits and multiple prior concussions. Former athletes are not at increased risk for death by suicide (two studies). Former high school American football players do not appear to be at increased risk for later life neurodegenerative diseases (two studies). Some retired professional American football players may be at increased risk for diminishment in cognitive functioning or mild cognitive impairment (several studies), and neurodegenerative diseases (one study). Neuroimaging studies show modest evidence of macrostructural, microstructural, functional and neurochemical changes in some athletes. Conclusion Multiple concussions appear to be a risk factor for cognitive impairment and mental health problems in some individuals. More research is needed to better understand the prevalence of chronic traumatic encephalopathy and other neurological conditions and diseases, and the extent to which they are related to concussions and/or repetitive neurotrauma sustained in sports. PMID:28455362

Plastic mulching in agriculture. Trading short-term agronomic benefits for long-term soil degradation?

PubMed

Steinmetz, Zacharias; Wollmann, Claudia; Schaefer, Miriam; Buchmann, Christian; David, Jan; Tröger, Josephine; Muñoz, Katherine; Frör, Oliver; Schaumann, Gabriele Ellen

2016-04-15

Plastic mulching has become a globally applied agricultural practice for its instant economic benefits such as higher yields, earlier harvests, improved fruit quality and increased water-use efficiency. However, knowledge of the sustainability of plastic mulching remains vague in terms of both an environmental and agronomic perspective. This review critically discusses the current understanding of the environmental impact of plastic mulch use by linking knowledge of agricultural benefits and research on the life cycle of plastic mulches with direct and indirect implications for long-term soil quality and ecosystem services. Adverse effects may arise from plastic additives, enhanced pesticide runoff and plastic residues likely to fragment into microplastics but remaining chemically intact and accumulating in soil where they can successively sorb agrochemicals. The quantification of microplastics in soil remains challenging due to the lack of appropriate analytical techniques. The cost and effort of recovering and recycling used mulching films may offset the aforementioned benefits in the long term. However, comparative and long-term agronomic assessments have not yet been conducted. Furthermore, plastic mulches have the potential to alter soil quality by shifting the edaphic biocoenosis (e.g. towards mycotoxigenic fungi), accelerate C/N metabolism eventually depleting soil organic matter stocks, increase soil water repellency and favour the release of greenhouse gases. A substantial process understanding of the interactions between the soil microclimate, water supply and biological activity under plastic mulches is still lacking but required to estimate potential risks for long-term soil quality. Currently, farmers mostly base their decision to apply plastic mulches rather on expected short-term benefits than on the consideration of long-term consequences. Future interdisciplinary research should therefore gain a deeper understanding of the incentives for farmers

Long-term academic stress enhances early processing of facial expressions.

PubMed

Zhang, Liang; Qin, Shaozheng; Yao, Zhuxi; Zhang, Kan; Wu, Jianhui

2016-11-01

Exposure to long-term stress can lead to a variety of emotional and behavioral problems. Although widely investigated, the neural basis of how long-term stress impacts emotional processing in humans remains largely elusive. Using event-related brain potentials (ERPs), we investigated the effects of long-term stress on the neural dynamics of emotionally facial expression processing. Thirty-nine male college students undergoing preparation for a major examination and twenty-one matched controls performed a gender discrimination task for faces displaying angry, happy, and neutral expressions. The results of the Perceived Stress Scale showed that participants in the stress group perceived higher levels of long-term stress relative to the control group. ERP analyses revealed differential effects of long-term stress on two early stages of facial expression processing: 1) long-term stress generally augmented posterior P1 amplitudes to facial stimuli irrespective of expression valence, suggesting that stress can increase sensitization to visual inputs in general, and 2) long-term stress selectively augmented fronto-central P2 amplitudes for angry but not for neutral or positive facial expressions, suggesting that stress may lead to increased attentional prioritization to processing negative emotional stimuli. Together, our findings suggest that long-term stress has profound impacts on the early stages of facial expression processing, with an increase at the very early stage of general information inputs and a subsequent attentional bias toward processing emotionally negative stimuli. Copyright © 2016 Elsevier B.V. All rights reserved.

Synaptic long-term potentiation realized in Pavlov's dog model based on a NiOx-based memristor

NASA Astrophysics Data System (ADS)

Hu, S. G.; Liu, Y.; Liu, Z.; Chen, T. P.; Yu, Q.; Deng, L. J.; Yin, Y.; Hosaka, Sumio

2014-12-01

Synaptic Long-Term Potentiation (LTP), which is a long-lasting enhancement in signal transmission between neurons, is widely considered as the major cellular mechanism during learning and memorization. In this work, a NiOx-based memristor is found to be able to emulate the synaptic LTP. Electrical conductance of the memristor is increased by electrical pulse stimulation and then spontaneously decays towards its initial state, which resembles the synaptic LTP. The lasting time of the LTP in the memristor can be estimated with the relaxation equation, which well describes the conductance decay behavior. The LTP effect of the memristor has a dependence on the stimulation parameters, including pulse height, width, interval, and number of pulses. An artificial network consisting of three neurons and two synapses is constructed to demonstrate the associative learning and LTP behavior in extinction of association in Pavlov's dog experiment.

Long-term potentiation decay and memory loss are mediated by AMPAR endocytosis.

PubMed

Dong, Zhifang; Han, Huili; Li, Hongjie; Bai, Yanrui; Wang, Wei; Tu, Man; Peng, Yan; Zhou, Limin; He, Wenting; Wu, Xiaobin; Tan, Tao; Liu, Mingjing; Wu, Xiaoyan; Zhou, Weihui; Jin, Wuyang; Zhang, Shu; Sacktor, Todd Charlton; Li, Tingyu; Song, Weihong; Wang, Yu Tian

2015-01-01

Long-term potentiation (LTP) of synaptic strength between hippocampal neurons is associated with learning and memory, and LTP dysfunction is thought to underlie memory loss. LTP can be temporally and mechanistically classified into decaying (early-phase) LTP and nondecaying (late-phase) LTP. While the nondecaying nature of LTP is thought to depend on protein synthesis and contribute to memory maintenance, little is known about the mechanisms and roles of decaying LTP. Here, we demonstrated that inhibiting endocytosis of postsynaptic α-amino-3-hydroxy-5-methyl-isoxazole-4-propionic acid receptors (AMPARs) prevents LTP decay, thereby converting it into nondecaying LTP. Conversely, restoration of AMPAR endocytosis by inhibiting protein kinase Mζ (PKMζ) converted nondecaying LTP into decaying LTP. Similarly, inhibition of AMPAR endocytosis prolonged memory retention in normal animals and reduced memory loss in a murine model of Alzheimer's disease. These results strongly suggest that an active process that involves AMPAR endocytosis mediates the decay of LTP and that inhibition of this process can prolong the longevity of LTP as well as memory under both physiological and pathological conditions.

Long-Term Learning in a Short-Term Study Abroad Program: "Are We Really Truly Helping the Community?".

PubMed

Caldwell, Penelope; Purtzer, Mary Anne

2015-01-01

To discover long-term learning outcomes in a short-term study abroad program. Students worked directly with community members to identify health issues, implement educational workshops addressing those issues, and evaluate health outcomes. This is a qualitative, descriptive study. Thematic analysis was conducted using a written questionnaire completed one or more years postimmersion. The sample was 41 nursing students who participated in a 10-day immersion experience in remote Honduras. Four themes emerged revealing evidence of long-term learning. Three of these themes, Embracing Other, Gaining Cultural Competencies, and Experiencing an Ethnocentric Shift, are supported in the literature. The fourth theme, Negotiating Ethical Dilemmas, offers a new finding. Although educators have questioned ethical consequences of study abroad programs, there is a paucity of literature indicating that students are the ones doing the questioning. Implications for educators and community members alike include facilitating dialog about collective worldviews related to global health ethics when designing study abroad programs. © 2014 Wiley Periodicals, Inc.

Antibiotic Use and Need for Antimicrobial Stewardship in Long-Term Care.

PubMed

Wu, Lisa Dong-Ying; Walker, Sandra A N; Elligsen, Marion; Palmay, Lesley; Simor, Andrew; Daneman, Nick

2015-01-01

Antimicrobial stewardship may be important in long-term care facilities because of unnecessary or inappropriate antibiotic use observed in these residents, coupled with their increased vulnerability to health care-associated infections. To assess antibiotic use in a long-term care facility in order to identify potential antimicrobial stewardship needs. A retrospective descriptive study was conducted at the Veterans Centre, a long-term care facility at Sunnybrook Health Sciences Centre, Toronto, Ontario. All residents taking one or more antibiotics (n = 326) were included as participants. Antibiotic-use data for patients residing in the facility between April 1, 2011, and March 31, 2012, were collected and analyzed. Totals of 358 patient encounters, 835 antibiotic prescriptions, and 193 positive culture results were documented during the study period. For 36% (302/835) of antibiotic prescriptions, the duration was more than 7 days. Cephalosporins (30%; 251/835) and fluoroquinolones (28%; 235/835) were the most frequently prescribed antibiotic classes. Urine was the most common source of samples for culture (60%; 116/193). Characteristics of antimicrobial use at this long-term care facility that might benefit from further evaluation included potentially excessive use of fluoroquinolones and cephalosporins and potentially excessive duration of antibiotic use for individual patients.

Formula for the Transition Probability Induced by Long-range Potential Terms Varying as R-8 and R-10 for Atom-dimer Collisions

NASA Astrophysics Data System (ADS)

Matthews, N. F.; Robson, D.; Grant, M. A.

1990-12-01

An explicit formula is derived for the transition probability between two different states of the atom-dimer collisional system governed by second-order long-range interaction potential terms varying as R-8 and R-10.

Prior Activation of Inositol 1,4,5-Trisphosphate Receptors Suppresses the Subsequent Induction of Long-Term Potentiation in Hippocampal CA1 Neurons

ERIC Educational Resources Information Center

Fujii, Satoshi; Yamazaki, Yoshihiko; Goto, Jun-Ichi; Fujiwara, Hiroki; Mikoshiba, Katsuhiko

2016-01-01

We investigated the role of inositol 1,4,5-trisphosphate receptors (IP3Rs) activated by preconditioning low-frequency afferent stimulation (LFS) in the subsequent induction of long-term potentiation (LTP) in CA1 neurons in hippocampal slices from mature guinea pigs. Induction of LTP in the field excitatory postsynaptic potential or the population…

Mice deficient in collapsin response mediator protein-1 exhibit impaired long-term potentiation and impaired spatial learning and memory.

PubMed

Su, Kang-Yi; Chien, Wei-Lin; Fu, Wen-Mei; Yu, I-Shing; Huang, Hsiang-Po; Huang, Pei-Hsing; Lin, Shu-Rung; Shih, Jin-Yuan; Lin, Yi-Ling; Hsueh, Yi-Ping; Yang, Pan-Chyr; Lin, Shu-Wha

2007-03-07

Collapsing response mediator protein-1 (CRMP-1) was initially identified in brain and has been implicated in plexin-dependent neuronal function. The high amino acid sequence identity among the five CRMPs has hindered determination of the functions of each individual CRMP. We generated viable and fertile CRMP-1 knock-out (CRMP-1(-/-)) mice with no evidence of gross abnormality in the major organs. CRMP-1(-/-) mice exhibited intense microtubule-associated protein 2 (MAP2) staining in the proximal portion of the dendrites, but reduced and disorganized MAP2 staining in the distal dendrites of hippocampal CA1 pyramidal cells. Immunoreactivity to GAP-43 (growth-associated protein-43) and PSD95 (postsynaptic density-95) (a postsynaptic membrane adherent cytoskeletal protein) was also decreased in the CA1 region of the knock-out mice. These changes were consistent with the mutant mice showing a reduction in long-term potentiation (LTP) in the CA1 region and impaired performance in hippocampal-dependent spatial learning and memory tests. CRMP-1(-/-) mice showed a normal synapsin I labeling pattern in CA1 and normal paired-pulse facilitation. These findings provide the first evidence suggesting that CRMP-1 may be involved in proper neurite outgrowth in the adult hippocampus and that loss of CRMP-1 may affect LTP maintenance and spatial learning and memory.

Long-term in vivo corrosion behavior, biocompatibility and bioresorption mechanism of a bioresorbable nitrided iron scaffold.

PubMed

Lin, Wenjiao; Qin, Li; Qi, Haiping; Zhang, Deyuan; Zhang, Gui; Gao, Runlin; Qiu, Hong; Xia, Ying; Cao, Ping; Wang, Xiang; Zheng, Wei

2017-05-01

Pure iron as a potential bioresorbable material for bioresorbable coronary scaffold has major disadvantages of slow corrosion and bioresorption. However, so far, there are neither quantitative data of long-term in vivo corrosion nor direct experimental evidence for bioresorption of pure iron and its alloys, which are fundamental and vital for developing novel Fe-based alloys overcoming the intrinsic drawbacks of pure iron. This work systemically investigated scaffold performance, long-term in vivo corrosion behavior and biocompatibility of a nitrided iron coronary scaffold and explored its bioresorption mechanism. It was found that the 70μm Fe-based scaffold was superior to a state of the art Co-Cr alloy stent (Xience Prime™) in terms of crossing profile, recoil and radial strength. Mass loss was 76.0±8.5wt% for the nitrided iron scaffold and 44.2±11.4wt% for the pure iron scaffold after 36months implantation in rabbit abdominal aorta (p<0.05). The Fe-based scaffold showed good long-term biocompatibility in both rabbit and porcine model. Its insoluble corrosion products were demonstrated biosafe and could be cleared away by macrophages from in situ to adventitia to be indiscernible by Micro Computed Tomography and probably finally enter the lymphatics and travel to lymph nodes after 53months implantion in porcine coronary artery. The results indicate that the nitrided iron scaffold with further improvements shall be promising for coronary application. Pure iron as a potential bioresorbable material has major disadvantages of slow corrosion and bioresorption. However, so far, there are neither quantitative data of long-term in vivo corrosion nor direct experimental evidence for bioresorption of pure iron and its alloys. Only this work systemically investigated long-term in vivo corrosion behavior and biocompatibility of a nitrided iron coronary scaffold up to 53months after implantation and explored its bioresorption mechanism. These are fundamental and vital

The association between long-term care setting and potentially preventable hospitalizations among older dual eligibles.

PubMed

Wysocki, Andrea; Kane, Robert L; Golberstein, Ezra; Dowd, Bryan; Lum, Terry; Shippee, Tetyana

2014-06-01

To compare the probability of experiencing a potentially preventable hospitalization (PPH) between older dual eligible Medicaid home and community-based service (HCBS) users and nursing home residents. Three years of Medicaid and Medicare claims data (2003-2005) from seven states, linked to area characteristics from the Area Resource File. A primary diagnosis of an ambulatory care sensitive condition on the inpatient hospital claim was used to identify PPHs. We used inverse probability of treatment weighting to mitigate the potential selection of HCBS versus nursing home use. The most frequent conditions accounting for PPHs were the same among the HCBS users and nursing home residents and included congestive heart failure, pneumonia, chronic obstructive pulmonary disease, urinary tract infection, and dehydration. Compared to nursing home residents, elderly HCBS users had an increased probability of experiencing both a PPH and a non-PPH. HCBS users' increased probability for potentially and non-PPHs suggests a need for more proactive integration of medical and long-term care. © Health Research and Educational Trust.

HIV-related politics in long-term perspective.

PubMed

Friedman, S R

1998-06-01

Some long-term, large-scale socio-economic changes may affect the politics of HIV and other emerging viruses such as hepatitis C. It is useful to ask why the potential peace dividend of the early 1990s failed to provide adequate resources for HIV-related social and medical service delivery in developed or developing nations. This failure can be understood by looking at long-term global economic trends and the pressures they put on governments and corporations. They have produced a period in which fundamental issues of political and economic structure are at stake and, often, the response is a divide-and-rule politics to promote stability. National politics differ in terms of the extent to which such a 'politics of scapegoating' is institutionalized and in terms of which groups are scapegoated. Groups such as drug injectors, gay and bisexual men and sex traders are particularly likely to be targeted both by the scapegoaters and by HIV. Given this framework, how should public health professionals and activists engaged in HIV-related issues respond? Under what circumstances should we orient efforts upwards towards corporate, political or bureaucratic leaders? Under what circumstances, and how, should we orient towards popular forces? Relatedly, we need to consider an issue we often ignore: What do we have to offer potential allies? That is, in terms of their goals, philosophies and needs, why should they ally with us?

Long-term Potentiation Decay and Poor Long-lasting Memory Process in the Wild Rodents Proechimys from Brazil's Amazon Rainforest.

PubMed

Guimarães Marques, Marcia J; Reyes-Garcia, Selvin Z; Marques-Carneiro, José E; Lopes-Silva, Leonardo B; Andersen, Monica L; Cavalheiro, Esper A; Scorza, Fulvio A; Scorza, Carla A

2018-01-01

Proechimys are small terrestrial rodents from Amazon rainforest. Each animal species is adapted to a specific environment in which the animal evolved therefore without comparative approaches unique characteristics of distinct species cannot be fully recognized. Laboratory rodents are exceedingly inbred strains dissociated from their native habitats and their fundamental ecological aspects are abstracted. Thus, the employment of exotic non-model species can be informative and complement conventional animal models. With the aim of promoting comparative studies between the exotic wildlife populations in the laboratory and traditional rodent model, we surveyed a type of synaptic plasticity intimately related to memory encoding in animals. Using theta-burst paradigm, in vitro long-term potentiation (LTP) in the CA1 subfield of hippocampal slices was assessed in the Amazon rodents Proechimys and Wistar rats. Memory, learning and anxiety were investigated through the plus-maze discriminative avoidance task (PM-DAT) and object recognition test. In PM-DAT, both animal species were submitted to two test sessions (3-h and 24-h) after the conditioning training. Proechimys exhibited higher anxiety-like behavior in the training session but during test sessions both species exhibited similar patterns of anxiety-related behavior. After 3-h of the training, Proechimys and Wistar spent significantly less time in the aversive enclosed arm than in the non-aversive arm. But, at 24-h after training, Wistar rats remained less time in the aversive closed arm in comparison with the non-aversive one, while Proechimys rodents spent the same amount of time in both enclosed arms. In the object recognition test, both species were evaluated at 24-h after the acquisition session and similar findings than those of the PM-DAT (24-h) were obtained, suggesting that long-term memory duration did not persist for 24-h in the Amazon rodent. Field excitatory post-synaptic potentials recordings revealed

Superior Long-Term Synaptic Memory Induced by Combining Dual Pharmacological Activation of PKA and ERK with an Enhanced Training Protocol

ERIC Educational Resources Information Center

Liu, Rong-Yu; Neveu, Curtis; Smolen, Paul; Cleary, Leonard J.; Byrne, John H.

2017-01-01

Developing treatment strategies to enhance memory is an important goal of neuroscience research. Activation of multiple biochemical signaling cascades, such as the protein kinase A (PKA) and extracellular signal-regulated kinase (ERK) pathways, is necessary to induce long-term synaptic facilitation (LTF), a correlate of long-term memory (LTM).…

Aniracetam attenuates H2O2-induced deficiency of neuron viability, mitochondria potential and hippocampal long-term potentiation of mice in vitro.

PubMed

Wang, Yong-Fu; Li, Chao-Cui; Cai, Jing-Xia

2006-09-01

Objective It is known that free radicals are involved in neurodegeneration and cognitive dysfunction, as seen in Alzheimer' s disease (AD) and aging. The present study examines the protective effects of aniracetam against H2O2-induced toxicity to neuron viability, mitochondria potential and hippocampal long-term potentiation (LTP). Methods Tetrazolium salt 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) was used to detect neuronal viability. MitoTracker Red (CMX Ros), a fluorescent stain for mitochondria, was used to measure mitochondria potential. Electrophysiological technique was carried out to record hippocampal LTP. Results H2O2 exposure impaired the viability of neurons, reduced mitochondria potential, and decreased LTP in the CA1 region of hippocampus. These deficient effects were significantly rescued by pre-treatment with aniracetam (10-100 mu mol/L). Conclusion These results indicate that aniracetam has a strong neuroprotective effect against H2O2-induced toxicity, which could partly explain the mechanism of its clinical application in neurodegenerative diseases.

Whereas Short-Term Facilitation Is Presynaptic, Intermediate-Term Facilitation Involves Both Presynaptic and Postsynaptic Protein Kinases and Protein Synthesis

ERIC Educational Resources Information Center

Jin, Iksung; Kandel, Eric R.; Hawkins, Robert D.

2011-01-01

Whereas short-term plasticity involves covalent modifications that are generally restricted to either presynaptic or postsynaptic structures, long-term plasticity involves the growth of new synapses, which by its nature involves both pre- and postsynaptic alterations. In addition, an intermediate-term stage of plasticity has been identified that…

Activation of Muscarinic M1 Acetylcholine Receptors Induces Long-Term Potentiation in the Hippocampus

PubMed Central

Dennis, Siobhan H.; Pasqui, Francesca; Colvin, Ellen M.; Sanger, Helen; Mogg, Adrian J.; Felder, Christian C.; Broad, Lisa M.; Fitzjohn, Steve M.; Isaac, John T.R.; Mellor, Jack R.

2016-01-01

Muscarinic M1 acetylcholine receptors (M1Rs) are highly expressed in the hippocampus, and their inhibition or ablation disrupts the encoding of spatial memory. It has been hypothesized that the principal mechanism by which M1Rs influence spatial memory is by the regulation of hippocampal synaptic plasticity. Here, we use a combination of recently developed, well characterized, selective M1R agonists and M1R knock-out mice to define the roles of M1Rs in the regulation of hippocampal neuronal and synaptic function. We confirm that M1R activation increases input resistance and depolarizes hippocampal CA1 pyramidal neurons and show that this profoundly increases excitatory postsynaptic potential-spike coupling. Consistent with a critical role for M1Rs in synaptic plasticity, we now show that M1R activation produces a robust potentiation of glutamatergic synaptic transmission onto CA1 pyramidal neurons that has all the hallmarks of long-term potentiation (LTP): The potentiation requires NMDA receptor activity and bi-directionally occludes with synaptically induced LTP. Thus, we describe synergistic mechanisms by which acetylcholine acting through M1Rs excites CA1 pyramidal neurons and induces LTP, to profoundly increase activation of CA1 pyramidal neurons. These features are predicted to make a major contribution to the pro-cognitive effects of cholinergic transmission in rodents and humans. PMID:26472558

Long-term care: The public role and private initiatives

PubMed Central

Burke, Thomas R.

1988-01-01

The ongoing effort of the U.S. Department of Health and Human Services to identify private financing mechanisms that can effectively assist the rapidly growing population of older persons in paying for long-term care expenses is discussed in this article. The focus on private strategies stems from the recognition that Federal and State sectors already pay almost one-half of all long-term care expenses, the proclivity of liberalized financing structures to raise total costs, and the tendency of public financing to dampen choice, flexibility, and access to care. In view of the improved economic situation of most older persons in our Nation today, the potential for market development of private financing options is thought to be excellent, particularly the market for long-term care insurance. PMID:10312961

Addressing homelessness among people with mental illnesses: a model of long-term philanthropic effectiveness.

PubMed

Brousseau, Ruth Tebbets

2009-01-01

Foundations are often criticized for their short attention spans and inability to continue funding the toughest social problems. Homelessness among people with mental illnesses is considered among the most intractable of social issues. This paper explores the role of permanent supportive housing in reducing homelessness among the mentally ill; the role of the Corporation for Supportive Housing in developing, authenticating, and disseminating its model; and its long-term funding relationship with the Conrad N. Hilton Foundation, which has facilitated this trajectory. The paper tells the story of how long-term funding, strategically used, is making inroads into this serious mental health problem.

Attention Problems, Phonological Short-Term Memory, and Visuospatial Short-Term Memory: Differential Effects on Near- and Long-Term Scholastic Achievement

ERIC Educational Resources Information Center

Sarver, Dustin E.; Rapport, Mark D.; Kofler, Michael J.; Scanlan, Sean W.; Raiker, Joseph S.; Altro, Thomas A.; Bolden, Jennifer

2012-01-01

The current study examined individual differences in children's phonological and visuospatial short-term memory as potential mediators of the relationship among attention problems and near- and long-term scholastic achievement. Nested structural equation models revealed that teacher-reported attention problems were associated negatively with…

A systematic review of potential long-term effects of sport-related concussion.

PubMed

Manley, Geoff; Gardner, Andrew J; Schneider, Kathryn J; Guskiewicz, Kevin M; Bailes, Julian; Cantu, Robert C; Castellani, Rudolph J; Turner, Michael; Jordan, Barry D; Randolph, Christopher; Dvořák, Jiří; Hayden, K Alix; Tator, Charles H; McCrory, Paul; Iverson, Grant L

2017-06-01

Systematic review of possible long-term effects of sports-related concussion in retired athletes. Ten electronic databases. Original research; incidence, risk factors or causation related to long-term mental health or neurological problems; individuals who have suffered a concussion; retired athletes as the subjects and possible long-term sequelae defined as > 10 years after the injury. Study population, exposure/outcome measures, clinical data, neurological examination findings, cognitive assessment, neuroimaging findings and neuropathology results. Risk of bias and level of evidence were evaluated by two authors. Following review of 3819 studies, 47 met inclusion criteria. Some former athletes have depression and cognitive deficits later in life, and there is an association between these deficits and multiple prior concussions. Former athletes are not at increased risk for death by suicide (two studies). Former high school American football players do not appear to be at increased risk for later life neurodegenerative diseases (two studies). Some retired professional American football players may be at increased risk for diminishment in cognitive functioning or mild cognitive impairment (several studies), and neurodegenerative diseases (one study). Neuroimaging studies show modest evidence of macrostructural, microstructural, functional and neurochemical changes in some athletes. Multiple concussions appear to be a risk factor for cognitive impairment and mental health problems in some individuals. More research is needed to better understand the prevalence of chronic traumatic encephalopathy and other neurological conditions and diseases, and the extent to which they are related to concussions and/or repetitive neurotrauma sustained in sports. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Long-term urethral catheterisation.

PubMed

Turner, Bruce; Dickens, Nicola

This article discusses long-term urethral catheterisation, focusing on the relevant anatomy and physiology, indications for the procedure, catheter selection and catheter care. It is important that nurses have a good working knowledge of long-term catheterisation as the need for this intervention will increase with the rise in chronic health conditions and the ageing population.

Long-term solar-terrestrial observations

NASA Technical Reports Server (NTRS)

1988-01-01

The results of an 18-month study of the requirements for long-term monitoring and archiving of solar-terrestrial data is presented. The value of long-term solar-terrestrial observations is discussed together with parameters, associated measurements, and observational problem areas in each of the solar-terrestrial links (the sun, the interplanetary medium, the magnetosphere, and the thermosphere-ionosphere). Some recommendations are offered for coordinated planning for long-term solar-terrestrial observations.

From ultrasocial to antisocial: a role for oxytocin in the acute reinforcing effects and long-term adverse consequences of drug use?

PubMed

McGregor, I S; Callaghan, P D; Hunt, G E

2008-05-01

Addictive drugs can profoundly affect social behaviour both acutely and in the long-term. Effects range from the artificial sociability imbued by various intoxicating agents to the depressed and socially withdrawn state frequently observed in chronic drug users. Understanding such effects is of great potential significance in addiction neurobiology. In this review we focus on the 'social neuropeptide' oxytocin and its possible role in acute and long-term effects of commonly used drugs. Oxytocin regulates social affiliation and social recognition in many species and modulates anxiety, mood and aggression. Recent evidence suggests that popular party drugs such as MDMA and gamma-hydroxybutyrate (GHB) may preferentially activate brain oxytocin systems to produce their characteristic prosocial and prosexual effects. Oxytocin interacts with the mesolimbic dopamine system to facilitate sexual and social behaviour, and this oxytocin-dopamine interaction may also influence the acquisition and expression of drug-seeking behaviour. An increasing body of evidence from animal models suggests that even brief exposure to drugs such as MDMA, cannabinoids, methamphetamine and phencyclidine can cause long lasting deficits in social behaviour. We discuss preliminary evidence that these adverse effects may reflect long-term neuroadaptations in brain oxytocin systems. Laboratory studies and preliminary clinical studies also indicate that raising brain oxytocin levels may ameliorate acute drug withdrawal symptoms. It is concluded that oxytocin may play an important, yet largely unexplored, role in drug addiction. Greater understanding of this role may ultimately lead to novel therapeutics for addiction that can improve mood and facilitate the recovery of persons with drug use disorders.

Long-term stable active mount for reflective optics

NASA Astrophysics Data System (ADS)

Reinlein, C.; Brady, A.; Damm, C.; Mohaupt, M.; Kamm, A.; Lange, N.; Goy, M.

2016-07-01

We report on the development of an active mount with an orthogonal actuator matrix offering a stable shape optimization for gratings or mirrors. We introduce the actuator distribution and calculate the accessible Zernike polynomials from their actuator influence function. Experimental tests show the capability of the device to compensate for aberrations of grating substrates as we report measurements of a 110x105 mm2 and 220x210 mm2 device With these devices, we evaluate the position depending aberrations, long-term stability shape results, and temperature-induced shape variations. Therewith we will discuss potential applications in space telescopes and Earth-based facilities where long-term stability is mandatory.

Mechanisms of Translation Control Underlying Long-lasting Synaptic Plasticity and the Consolidation of Long-term Memory

PubMed Central

Santini, Emanuela; Huynh, Thu N.; Klann, Eric

2018-01-01

The complexity of memory formation and its persistence is a phenomenon that has been studied intensely for centuries. Memory exists in many forms and is stored in various brain regions. Generally speaking, memories are reorganized into broadly distributed cortical networks over time through systems level consolidation. At the cellular level, storage of information is believed to initially occur via altered synaptic strength by processes such as long-term potentiation (LTP). New protein synthesis is required for long-lasting synaptic plasticity as well as for the formation of long-term memory. The mammalian target of rapamycin complex 1 (mTORC1) is a critical regulator of cap-dependent protein synthesis and is required for numerous forms of long-lasting synaptic plasticity and long-term memory. As such, the study of mTORC1 and protein factors that control translation initiation and elongation have enhanced our understanding of how the process of protein synthesis is regulated during memory formation. Herein we will discuss the molecular mechanisms that regulate protein synthesis as well as pharmacological and genetic manipulations that demonstrate the requirement for proper translational control in long-lasting synaptic plasticity and long-term memory formation. PMID:24484700

Long-term care: long-term care insurance--2005. End of Year Issue Brief.

PubMed

Tanner, Rachel; Bercaw, Lawren

2005-12-31

As the "Baby Boom" generation approaches retirement, state and federal lawmakers are struggling to ensure that the nation's long-term care system will provide adequate services for the growing number of senior citizens. A 2003 Administration on Aging report predicted that the elderly population will double by 2030. Accordingly, policymakers must prepare for the impending squeeze on public health and Medicaid resources. Many consumers are exploring private long-term care insurance options as a means of preparing for the cost of eldercare. Yet, a lack of market uniformity has rendered the long-term care insurance industry somewhat difficult for consumers to decipher. In addition, senior care insurance is often costly, particularly for those over age 50.

Facilitating Long-Term Recovery from Natural Disasters: Psychosocial Programming for Tsunami-Affected Schools of Sri Lanka

ERIC Educational Resources Information Center

Nastasi, Bonnie K.; Jayasena, Asoka; Summerville, Meredith; Borja, Amanda P.

2011-01-01

This article reports the findings of a school-based intervention project conducted in the Southern Province of Sri Lanka 15 to 18 months after the December 2004 Tsunami. The work responds to the need for culturally relevant programming to address long-term psychosocial recovery of children and adolescents affected by large scale disasters. Program…

Long-term prognosis of depression in primary care.

PubMed Central

Simon, G. E.

2000-01-01

This article uses longitudinal data from a primary care sample to examine long-term prognosis of depression. A sample of 225 patients initiating antidepressant treatment in primary care completed assessments of clinical outcome (Hamilton Depression Rating Scale and the mood module of the Structured Clinical Interview for DSM-IIIR) 1, 3, 6, 9, 12, 18 and 24 months after initiating treatment. The proportion of patients continuing to meet criteria for major depression fell rapidly to approximately 10% and remained at approximately that level throughout follow-up. The proportion meeting criteria for remission (Hamilton Depression score of 7 or less) rose gradually to approximately 45%. Long-term prognosis (i.e. probability of remission at 6 months and beyond) was strongly related to remission status at 3 months (odds ratio 3.65; 95% confidence interval, 2.81-4.76) and only modestly related to various clinical characteristics assessed at baseline (e.g. prior history of recurrent depression, medical comorbidity, comorbid anxiety symptoms). The findings indicate that potentially modifiable risk factors influence the long-term prognosis of depression. This suggests that more systematic and effective depression treatment programmes might have an important effect on long-term course and reduce the overall burden of chronic and recurrent depression. PMID:10885162

Acute intermittent hypoxia induced phrenic long-term facilitation despite increased SOD1 expression in a rat model of ALS

PubMed Central

Nichols, Nicole L.; Satriotomo, Irawan; Harrigan, Daniel J.; Mitchell, Gordon S.

2015-01-01

Amyotrophic lateral sclerosis (ALS) is a progressive and fatal neurodegenerative disease characterized by motor neuron death. Since most ALS patients succumb to ventilatory failure from loss of respiratory motor neurons, any effective ALS treatment must preserve and/or restore breathing capacity. In rats over-expressing mutated superoxide dismutase-1 (SOD1G93A), the capacity to increase phrenic motor output is decreased at disease end-stage, suggesting imminent ventilatory failure. Acute intermittent hypoxia (AIH) induces phrenic long-term facilitation (pLTF), a form of spinal respiratory motor plasticity with potential to restore phrenic motor output in clinical disorders that compromise breathing. Since pLTF requires NADPH oxidase activity and reactive oxygen species (ROS) formation, it is blocked by NADPH oxidase inhibition and SOD mimetics in normal rats. Thus, we hypothesized that SOD1G93A (mutant; MT) rats do not express AIH-induced pLTF due to over-expression of active mutant superoxide dismutase-1. AIH-induced pLTF and hypoglossal (XII) LTF were assessed in young, pre-symptomatic and end-stage anesthetized MT rats and age-matched wild-type littermates. Contrary to predictions, pLTF and XII LTF were observed in MT rats at all ages; at end-stage, pLTF was actually enhanced. SOD1 levels were elevated in young and pre-symptomatic MT rats, yet superoxide accumulation in putative phrenic motor neurons (assessed with dihydroethidium) was unchanged; however, superoxide accumulation significantly decreased at end-stage. Thus, compensatory mechanisms appear to maintain ROS homoeostasis until late in disease progression, preserving AIH-induced respiratory plasticity. Following intrathecal injections of an NADPH oxidase inhibitor (apocynin; 600µM; 12µL), pLTF was abolished in pre-symptomatic, but not end-stage MT rats, demonstrating that pLTF is NADPH oxidase dependent in pre-symptomatic, but NADPH oxidase independent in end-stage MT rats. Mechanisms preserving

Long-term bed degradation in Maryland streams (phase 2) : Blue Ridge and Western Piedmont provinces.

DOT National Transportation Integrated Search

2012-03-01

Estimation of potential long-term down-cutting of the stream bed is necessary for evaluation and design of bridges for scour and culverts for fish passage. The purpose of this study has been to improve predictions of this potential long-term bed degr...

Developmental shift from long-term depression to long-term potentiation in the rat medial vestibular nuclei: role of group I metabotropic glutamate receptors.

PubMed

Puyal, Julien; Grassi, Silvarosa; Dieni, Cristina; Frondaroli, Adele; Demêmes, Danielle; Raymond, Jaqueline; Pettorossi, Vito Enrico

2003-12-01

The effects of high frequency stimulation (HFS) of the primary vestibular afferents on synaptic transmission in the ventral part of the medial vestibular nuclei (vMVN) were studied during postnatal development and compared with the changes in the expression of the group I metabotropic glutamate receptor (mGluR) subtypes, mGluR1 and mGluR5. During the first stages of development, HFS always induced a mGluR5- and GABAA-dependent long-term depression (LTD) which did not require NMDA receptor and mGluR1 activation. The probability of inducing LTD decreased progressively throughout the development and it was zero at about the end of the second postnatal week. Conversely, long-term potentiation (LTP) appeared at the beginning of the second week and its occurrence increased to reach the adult value at the end of the third week. Of interest, the sudden change in the LTP frequency occurred at the time of eye opening, about the end of the second postnatal week. LTP depended on NMDA receptor and mGluR1 activation. In parallel with the modifications in synaptic plasticity, we observed that the expression patterns and localizations of mGluR5 and mGluR1 in the medial vestibular nuclei (MVN) changed during postnatal development. At the earlier stages the mGluR1 expression was minimal, then increased progressively. In contrast, mGluR5 expression was initially high, then decreased. While mGluR1 was exclusively localized in neuronal compartments and concentrated at the postsynaptic sites at all stages observed, mGluR5 was found mainly in neuronal compartments at immature stages, then preferentially in glial compartments at mature stages. These results provide the first evidence for a progressive change from LTD to LTP accompanied by a distinct maturation expression of mGluR1 and mGluR5 during the development of the MVN.

Developmental shift from long-term depression to long-term potentiation in the rat medial vestibular nuclei: role of group I metabotropic glutamate receptors

PubMed Central

Puyal, Julien; Grassi, Silvarosa; Dieni, Cristina; Frondaroli, Adele; Demêmes, Danielle; Raymond, Jaqueline; Pettorossi, Vito Enrico

2003-01-01

The effects of high frequency stimulation (HFS) of the primary vestibular afferents on synaptic transmission in the ventral part of the medial vestibular nuclei (vMVN) were studied during postnatal development and compared with the changes in the expression of the group I metabotropic glutamate receptor (mGluR) subtypes, mGluR1 and mGluR5. During the first stages of development, HFS always induced a mGluR5- and GABAA-dependent long-term depression (LTD) which did not require NMDA receptor and mGluR1 activation. The probability of inducing LTD decreased progressively throughout the development and it was zero at about the end of the second postnatal week. Conversely, long-term potentiation (LTP) appeared at the beginning of the second week and its occurrence increased to reach the adult value at the end of the third week. Of interest, the sudden change in the LTP frequency occurred at the time of eye opening, about the end of the second postnatal week. LTP depended on NMDA receptor and mGluR1 activation. In parallel with the modifications in synaptic plasticity, we observed that the expression patterns and localizations of mGluR5 and mGluR1 in the medial vestibular nuclei (MVN) changed during postnatal development. At the earlier stages the mGluR1 expression was minimal, then increased progressively. In contrast, mGluR5 expression was initially high, then decreased. While mGluR1 was exclusively localized in neuronal compartments and concentrated at the postsynaptic sites at all stages observed, mGluR5 was found mainly in neuronal compartments at immature stages, then preferentially in glial compartments at mature stages. These results provide the first evidence for a progressive change from LTD to LTP accompanied by a distinct maturation expression of mGluR1 and mGluR5 during the development of the MVN. PMID:12972627

Prenatal exposure to a cannabinoid agonist produces memory deficits linked to dysfunction in hippocampal long-term potentiation and glutamate release.

PubMed

Mereu, Giampaolo; Fà, Mauro; Ferraro, Luca; Cagiano, Raffaele; Antonelli, Tiziana; Tattoli, Maria; Ghiglieri, Veronica; Tanganelli, Sergio; Gessa, Gian Luigi; Cuomo, Vincenzo

2003-04-15

To investigate the possible long-term consequences of gestational exposure to cannabinoids on cognitive functions, pregnant rats were administered with the CB1 receptor agonist WIN 55,212-2 (WIN), at a dose (0.5 mgkg) that causes neither malformations nor overt signs of toxicity. Prenatal WIN exposure induced a disruption of memory retention in 40- and 80-day-old offspring subjected to a passive avoidance task. A hyperactive behavior at the ages of 12 and 40 days was also found. The memory impairment caused by the gestational exposure to WIN was correlated with alterations of hippocampal long-term potentiation (LTP) and glutamate release. LTP induced in CA3-CA1 synapses decayed faster in brain slices of rats born from WIN-treated dams, whereas posttetanic and short-term potentiation were similar to the control group. In line with LTP shortening, in vivo microdialysis showed a significant decrease in basal and K(+)-evoked extracellular glutamate levels in the hippocampus of juvenile and adult rats born from WIN-treated dams. A similar reduction in glutamate outflow was also observed in primary cell cultures of hippocampus obtained from pups born from mothers exposed to WIN. The decrease in hippocampal glutamate outflow appears to be the cause of LTP disruption, which in turn might underlie, at least in part, the long-lasting impairment of cognitive functions caused by the gestational exposure to this cannabinoid agonist. These findings could provide an explanation of cognitive alterations observed in children born from women who use marijuana during pregnancy.

Dying with Dementia in Long-Term Care

ERIC Educational Resources Information Center

Sloane, Philip D.; Zimmerman, Sheryl; Williams, Christianna S.; Hanson, Laura C.

2008-01-01

Purpose: To better understand the experiences and potential unmet need of persons who die in long-term care. Design and Methods: We conducted after-death interviews with staff who had cared for 422 decedents with dementia and 159 who were cognitively intact and received terminal care in U.S. nursing homes (NHs) or residential care-assisted living…

Assessing the associative deficit of older adults in long-term and short-term/working memory.

PubMed

Chen, Tina; Naveh-Benjamin, Moshe

2012-09-01

Older adults exhibit a deficit in associative long-term memory relative to younger adults. However, the literature is inconclusive regarding whether this deficit is attenuated in short-term/working memory. To elucidate the issue, three experiments assessed younger and older adults' item and interitem associative memory and the effects of several variables that might potentially contribute to the inconsistent pattern of results in previous studies. In Experiment 1, participants were tested on item and associative recognition memory with both long-term and short-term retention intervals in a single, continuous recognition paradigm. There was an associative deficit for older adults in the short-term and long-term intervals. Using only short-term intervals, Experiment 2 utilized mixed and blocked test designs to examine the effect of test event salience. Blocking the test did not attenuate the age-related associative deficit seen in the mixed test blocks. Finally, an age-related associative deficit was found in Experiment 3, under both sequential and simultaneous presentation conditions. Even while accounting for some methodological issues, the associative deficit of older adults is evident in short-term/working memory.

Resting State Synchrony in Long-Term Abstinent Alcoholics

PubMed Central

Camchong, Jazmin; Stenger, Andy; Fein, George

2012-01-01

BACKGROUND Alcohol dependence (ALC) is a disorder with an impulsive and compulsive “drive” towards alcohol consumption and an inability to inhibit alcohol consumption. Neuroimaging studies suggest that these behavioral components correspond to an increased involvement of regions that mediate appetitive drive and reduced involvement of regions that mediate executive control within top-down networks. Little is known, however, about whether these characteristics are present after long periods of abstinence. METHODS Resting state functional magnetic resonance imaging data were collected to examine resting state synchrony (RSS) differences between 23 long-term abstinent alcoholics (LTAA; 8 females, age: M=48.46, SD=7.10), and 23 non-substance abusing controls (NSAC; 8 females, age: M=47.99, SD=6.70). Using seed-based measures, we examined resting-state synchrony with the nucleus accumbens (NAcc) and the subgenual anterior cingulate cortex (ACC). All participants were assessed with the intra/extradimensional set shift task outside of the scanner to explore the relationship between RSS and cognitive flexibility. RESULTS Compared to NSAC, LTAA showed (a) decreased synchrony of limbic reward regions (e.g., caudate and thalamus) with both the ACC seed and the NAcc seed and (b) increased synchrony of executive control regions (e.g., DLPFC) with both the NAcc seed and the subgenual ACC seed. RSS differences were significantly correlated with task performance. CONCLUSIONS The results are consistent with an interpretation of an ongoing compensatory mechanism in long-term abstinent alcoholics evident during rest, in which decision making networks show reduced synchrony with appetitive drive regions and increased synchrony with inhibitory control regions. In addition, RSS differences were associated with cognitive flexibility. These resting state findings indicate an adaptive mechanism present in long-term abstinence that may facilitate the behavioral control required for to

Long-term associative learning predicts verbal short-term memory performance.

PubMed

Jones, Gary; Macken, Bill

2018-02-01

Studies using tests such as digit span and nonword repetition have implicated short-term memory across a range of developmental domains. Such tests ostensibly assess specialized processes for the short-term manipulation and maintenance of information that are often argued to enable long-term learning. However, there is considerable evidence for an influence of long-term linguistic learning on performance in short-term memory tasks that brings into question the role of a specialized short-term memory system separate from long-term knowledge. Using natural language corpora, we show experimentally and computationally that performance on three widely used measures of short-term memory (digit span, nonword repetition, and sentence recall) can be predicted from simple associative learning operating on the linguistic environment to which a typical child may have been exposed. The findings support the broad view that short-term verbal memory performance reflects the application of long-term language knowledge to the experimental setting.

Asthma Medicines: Long-Term Control

MedlinePlus

... Size Email Print Share Asthma Medicines: Long-term Control Page Content Article Body Corticosteroids Synthetic versions of ... form, they are used exclusively for long-term control; they are not very effective for acute symptoms. ...

Cross-cultural comparison of long-term care in the United States and Finland: Research done through a short-term study-abroad experience.

PubMed

Kruger, Tina M; Gilland, Sarah; Frank, Jacquelyn B; Murphy, Bridget C; English, Courtney; Meade, Jana; Morrow, Kaylee; Rush, Evan

2017-01-01

In May 2014, a short-term study-abroad experience was conducted in Finland through a course offered at Indiana State University (ISU). Students and faculty from ISU and Eastern Illinois University participated in the experience, which was created to facilitate a cross-cultural comparison of long-term-care settings in the United States and Finland. With its outstanding system of caring for the health and social needs of its aging populace, Finland is a logical model to examine when considering ways to improve the quality of life for older adults who require care in the United States . Those participating in the course visited a series of long-term-care facilities in the region surrounding Terre Haute, Indiana, then travelled to Lappeenranta, Finland to visit parallel sites. Through limited-participation observation and semistructured interviews, similarities and differences in experiences, educations, and policies affecting long-term care workers in the United States and Finland were identified and are described here.

Short-term treatment with flumazenil restores long-term object memory in a mouse model of Down syndrome.

PubMed

Colas, Damien; Chuluun, Bayarsaikhan; Garner, Craig C; Heller, H Craig

2017-04-01

Down syndrome (DS) is a common genetic cause of intellectual disability yet no pro-cognitive drug therapies are approved for human use. Mechanistic studies in a mouse model of DS (Ts65Dn mice) demonstrate that impaired cognitive function is due to excessive neuronal inhibitory tone. These deficits are normalized by chronic, short-term low doses of GABA A receptor (GABA A R) antagonists in adult animals, but none of the compounds investigated are approved for human use. We explored the therapeutic potential of flumazenil (FLUM), a GABA A R antagonist working at the benzodiazepine binding site that has FDA approval. Long-term memory was assessed by the Novel Object Recognition (NOR) testing in Ts65Dn mice after acute or short-term chronic treatment with FLUM. Short-term, low, chronic dose regimens of FLUM elicit long-lasting (>1week) normalization of cognitive function in both young and aged mice. FLUM at low dosages produces long lasting cognitive improvements and has the potential of fulfilling an unmet therapeutic need in DS. Copyright © 2017. Published by Elsevier Inc.

Are we missing the boat? Current uses of long-term biological monitoring data in the evaluation and management of marine protected areas.

PubMed

Addison, P F E; Flander, L B; Cook, C N

2015-02-01

Protected area management agencies are increasingly using management effectiveness evaluation (MEE) to better understand, learn from and improve conservation efforts around the globe. Outcome assessment is the final stage of MEE, where conservation outcomes are measured to determine whether management objectives are being achieved. When quantitative monitoring data are available, best-practice examples of outcome assessments demonstrate that data should be assessed against quantitative condition categories. Such assessments enable more transparent and repeatable integration of monitoring data into MEE, which can promote evidence-based management and improve public accountability and reporting. We interviewed key informants from marine protected area (MPA) management agencies to investigate how scientific data sources, especially long-term biological monitoring data, are currently informing conservation management. Our study revealed that even when long-term monitoring results are available, management agencies are not using them for quantitative condition assessment in MEE. Instead, many agencies conduct qualitative condition assessments, where monitoring results are interpreted using expert judgment only. Whilst we found substantial evidence for the use of long-term monitoring data in the evidence-based management of MPAs, MEE is rarely the sole mechanism that facilitates the knowledge transfer of scientific evidence to management action. This suggests that the first goal of MEE (to enable environmental accountability and reporting) is being achieved, but the second and arguably more important goal of facilitating evidence-based management is not. Given that many MEE approaches are in their infancy, recommendations are made to assist management agencies realize the full potential of long-term quantitative monitoring data for protected area evaluation and evidence-based management. Copyright © 2014 Elsevier Ltd. All rights reserved.

Synaptic Transmission Optimization Predicts Expression Loci of Long-Term Plasticity.

PubMed

Costa, Rui Ponte; Padamsey, Zahid; D'Amour, James A; Emptage, Nigel J; Froemke, Robert C; Vogels, Tim P

2017-09-27

Long-term modifications of neuronal connections are critical for reliable memory storage in the brain. However, their locus of expression-pre- or postsynaptic-is highly variable. Here we introduce a theoretical framework in which long-term plasticity performs an optimization of the postsynaptic response statistics toward a given mean with minimal variance. Consequently, the state of the synapse at the time of plasticity induction determines the ratio of pre- and postsynaptic modifications. Our theory explains the experimentally observed expression loci of the hippocampal and neocortical synaptic potentiation studies we examined. Moreover, the theory predicts presynaptic expression of long-term depression, consistent with experimental observations. At inhibitory synapses, the theory suggests a statistically efficient excitatory-inhibitory balance in which changes in inhibitory postsynaptic response statistics specifically target the mean excitation. Our results provide a unifying theory for understanding the expression mechanisms and functions of long-term synaptic transmission plasticity. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Ventricular Late Potentials Immediately Post ST-Elevation Myocardial Infarction, and Very Long-Term Mortality.

PubMed

Shturman, Alexander; Vardi, Shira; Bickel, Amitai; Atar, Shaul

2017-04-01

The very long-term prognostic significance of ventricular late potentials (VLP) in patients post ST-elevation myocardial infarction (STEMI) is unclear. To evaluate the long-term predictive value of VLP for mortality post-STEMI. We conducted serial signal-averaged electrocardiography (SAECG) measurements in 63 patients on the 1st, 2nd and 3rd day pre-discharge, and 30 days after STEMI in patients admitted in 2001. We followed the patients for 10 years and correlated the presence of VLP with all-cause and cardiovascular mortality. The mean age was 59.9 ± 12.3 years. Thrombolysis was performed in 41 patients (65%). Percutaneous coronary intervention was performed pre-discharge in 40 patients (63%) and coronary artery bypass grafting in 7 (11%). Five consecutive measurements to define the presence of VLP were obtained in 52 patients (21 with VLP and 31 without). We found a higher prevalence of VLP in males compared to females (QRS segment > 114 msec, 51% vs. 12%, P = 0.02, duration of the low amplitude signal < 40 mV) in the terminal portion of the averaged QRS complex > 38 msec, 47% vs. 25%, P = 0.05). Over 10 years of follow-up, 14 (22%) patients died, 10 (70%) due to cardiovascular non-arrhythmic complications, 6 with VLP compared to only 3 without (28.6% vs. 9.7%, P = 0.125, hazard ratio = 2.96, confidence intervals = 0.74-11.84) (are these numbers meant to total 10?). Over 10 years of follow-up, the presence of VLP in early post-STEMI is not predictive of arrhythmic or non-arrhythmic cardiovascular mortality.

Long-term facilitation of ventilation following acute continuous hypoxia in awake humans during sustained hypercapnia

PubMed Central

Griffin, Harry S; Pugh, Keith; Kumar, Prem; Balanos, George M

2012-01-01

In awake humans, long-term facilitation of ventilation (vLTF) following acute intermittent hypoxia (AIH) is only expressed if CO2 is maintained above normocapnic levels. vLTF has not been reported following acute continuous hypoxia (ACH) and it is not known whether this might be unmasked by elevated CO2. Twelve healthy participants completed three trials. In all trials end-tidal pressure of CO2 was elevated 4–5 mmHg above normocapnic levels. During Trial 1 (AIH) participants were exposed to eight 4 min episodes of hypoxia. During Trial 2 (ACH) participants were exposed to continuous hypoxia for 32 min. In Trial 3 (Control) participants were exposed to euoxia throughout. To assess the contribution of the carotid body (CB) in observed ventilatory responses, CB afferent discharge before and after each trial was transiently inhibited with hyperoxia. Minute ventilation () increased following all trials, but was significantly greater in Trials 1 and 2 when compared with Trial 3 (Trial 1: 4.96 ± 0.87, Trial 2: 5.07 ± 0.7, Trial 3: 2.55 ± 0.98 l min−1, P < 0.05). Hyperoxia attenuated to a similar extent in baseline and recovery in all trials (Trial 1: 3.0 ± 0.57 vs. 3.27 ± 0.68, Trial 2: 1.97 ± 0.62 vs. 2.56 ± 0.62, Trial 3: 2.23 ± 0.49 vs. 2.15 ± 0.55 l min−1, P > 0.05). Data are means ± SEM. In awake humans with elevated CO2, ACH evokes a sustained increase in ventilation that is comparable to that evoked by AIH. However, a gradual positive drift in ventilation in response to elevated CO2 accounts for approximately half of this apparent vLTF. Additionally, our data support the view that the CB is not directly involved in maintaining vLTF. PMID:22826133

Enabling Long-Term Oceanographic Research: Changing Data Practices, Information Management Strategies and Informatics

NASA Astrophysics Data System (ADS)

Baker, K. S.; Chandler, C. L.

2008-12-01

Data management and informatics research are in a state of change in terms of data practices, information strategies, and roles. New ways of thinking about data and data management can facilitate interdisciplinary global ocean science. To meet contemporary expectations for local data use and reuse by a variety of audiences, collaborative strategies involving diverse teams of information professionals are developing. Such changes are fostering the growth of information infrastructures that support multi-scale sampling, data integration, and nascent networks of data repositories. In this retrospective, two examples of oceanographic projects incorporating data management in partnership with long-term science programs are reviewed: the Palmer Station Long-Term Ecological Research program (Palmer LTER) and the United States Joint Global Ocean Flux Study (US JGOFS). Lessons learned - short-term and long-term - from a decade of data management within these two communities will be presented. A conceptual framework called Ocean Informatics provides one example for managing the complexities inherent to sharing oceanographic data. Elements are discussed that address the economies-of-scale as well as the complexities-of-scale pertinent to a broad vision of information management and scientific research.

NMDA receptor-mediated long term modulation of electrically evoked field potentials in the rat medial vestibular nuclei.

PubMed

Capocchi, G; Della Torre, G; Grassi, S; Pettorossi, V E; Zampolini, M

1992-01-01

The effect of high frequency stimulation (HFS) of the primary vestibular afferents on field potentials recorded in the ipsilateral Medial Vestibular Nuclei (MVN) was studied. Our results show that potentiation and depression can be induced in different portions of MVN, which are distinguishable by their anatomical organization. HFS induces potentiation of the monosynaptic component in the ventral portion of the MVN, whereas it provokes depression of the polysynaptic component in the dorsal portion of the same nucleus. The induction of both potentiation and depression was blocked under AP5 perfusion, thus demonstrating that NMDA receptor activation mediates both phenomena. Furthermore, the finding that the field potentials were not modified during perfusion with DL-AP5, as previously reported, supports the hypothesis that NMDA receptors are not involved in the normal synaptic transmission from the primary vestibular afferent fibres, but are only activated following hyperstimulation of this afferent system. Our results suggest that the mechanisms of long term modification of synaptic efficacy observed in MVN may underlie the plasticity phenomena occurring in vestibular nuclei.

The Role of Long-Term Memory in a Test of Visual Working Memory: Proactive Facilitation but no Proactive Interference

PubMed Central

Oberauer, Klaus; Awh, Edward; Sutterer, David W.

2016-01-01

We report four experiments examining whether associations in visual working memory are subject to proactive interference from long term memory (LTM). Following a long-term learning phase in which participants learned the colors of 120 unique objects, a working memory (WM) test was administered in which participants recalled the precise colors of three concrete objects in an array. Each array in the WM test consisted of one old (previously learned) object with a new color (old-mismatch), one old object with its old color (old-match), and one new object. Experiments 1 to 3 showed that WM performance was better in the old-match condition than in the new condition, reflecting a beneficial contribution from long term memory. In the old mismatch condition, participants sometimes reported colors associated with the relevant shape in LTM, but the probability of successful recall was equivalent to that in the new condition. Thus, information from LTM only intruded in the absence of reportable information in WM. Experiment 4 tested for, and failed to find, proactive interference from the preceding trial in the WM test: Performance in the old-mismatch condition, presenting an object from the preceding trial with a new color, was equal to performance with new objects. Experiment 5 showed that long-term memory for object-color associations is subject to proactive interference. We conclude that the exchange of information between LTM and WM appears to be controlled by a gating mechanism that protects the contents of WM from proactive interference but admits LTM information when it is useful. PMID:27685018

Related Studies in Long Term Lithium Battery Stability

NASA Technical Reports Server (NTRS)

Horning, R. J.; Chua, D. L.

1984-01-01

The continuing growth of the use of lithium electrochemical systems in a wide variety of both military and industrial applications is primarily a result of the significant benefits associated with the technology such as high energy density, wide temperature operation and long term stability. The stability or long term storage capability of a battery is a function of several factors, each important to the overall storage life and, therefore, each potentially a problem area if not addressed during the design, development and evaluation phases of the product cycle. Design (e.g., reserve vs active), inherent material thermal stability, material compatibility and self-discharge characteristics are examples of factors key to the storability of a power source.

Reforming long-term care financing through insurance

PubMed Central

Meiners, Mark R.

1988-01-01

Until recently, insurance for long-term care was not viewed as feasible. This perception has changed dramatically in the past few years. Several models of long-term care insurance have begun to be tested. Although the application of insurance principles to long-term care is still new, the emergence of private market interest in developing long-term care insurance has been a catalyst to renewed public-policy support for reforming the way we pay for long-term care. States, in particular, have become interested in developing public-private partnerships to support the emergence of long-term care insurance that could help relieve the mounting pressure on Medicaid budgets. PMID:10312962

Mobile Phone and Tablet Apps to Support Young People's Management of Their Physical Long-Term Conditions: A Systematic Review Protocol.

PubMed

Majeed-Ariss, Rabiya; Hall, Andrew G; McDonagh, Janet; Fallon, Deborah; Swallow, Veronica

2015-04-07

The prevalence of long-term or chronic conditions that limit activity and reduce quality of life in young people aged 10-24 years is rising. This group has distinct health care needs and requires tailored support strategies to facilitate increasing personal responsibility for the management of their condition wherever possible, as they mature. Mobile phone and tablet mobile technologies featuring software program apps are already well used by young people for social networking or gaming. They have also been utilized in health care to support personal condition management, using condition-specific and patient-tailored software. Such apps have much potential, and there is an emerging body of literature on their use in a health context making this review timely. The objective of this paper is to develop a systematic review protocol focused on identifying and assessing the effectiveness of mobile phone and tablet apps that support young people's management of their chronic conditions. The search strategy will include a combination of standardized indexed search terms and free-text terms related to the key concepts of young people; long-term conditions and mobile technology. Peer-reviewed journal articles published from 2003 that meet the inclusion and exclusion criteria will be identified through searching the generated hits from 5 bibliographical databases. Two independent reviewers will screen the titles and abstracts to determine which articles focus on testing interventions identified as a mobile phone or tablet apps, and that have been designed and delivered to support the management of long-term conditions in young people aged 10-24 years. Data extraction and quality assessment tools will be used to facilitate consistent analysis and synthesis. It is anticipated that several studies will meet the selection criteria but that these are likely to be heterogeneous in terms of study design, reported outcomes, follow-up times, participants' age, and health condition

Soil quality assessment in long-term direct seed

USDA-ARS?s Scientific Manuscript database

Producers in the Pacific Northwest are adopting direct seed farming to reduce soil erosion, improve soil quality and increase water infiltration. Some direct seed producers are concerned with reaching the yield and profit potential expected with long-term direct seed, and this may be due to soil st...

Long-term Potentiation Decay and Poor Long-lasting Memory Process in the Wild Rodents Proechimys from Brazil’s Amazon Rainforest

PubMed Central

Guimarães Marques, Marcia J.; Reyes-Garcia, Selvin Z.; Marques-Carneiro, José E.; Lopes-Silva, Leonardo B.; Andersen, Monica L.; Cavalheiro, Esper A.; Scorza, Fulvio A.; Scorza, Carla A.

2018-01-01

Proechimys are small terrestrial rodents from Amazon rainforest. Each animal species is adapted to a specific environment in which the animal evolved therefore without comparative approaches unique characteristics of distinct species cannot be fully recognized. Laboratory rodents are exceedingly inbred strains dissociated from their native habitats and their fundamental ecological aspects are abstracted. Thus, the employment of exotic non-model species can be informative and complement conventional animal models. With the aim of promoting comparative studies between the exotic wildlife populations in the laboratory and traditional rodent model, we surveyed a type of synaptic plasticity intimately related to memory encoding in animals. Using theta-burst paradigm, in vitro long-term potentiation (LTP) in the CA1 subfield of hippocampal slices was assessed in the Amazon rodents Proechimys and Wistar rats. Memory, learning and anxiety were investigated through the plus-maze discriminative avoidance task (PM-DAT) and object recognition test. In PM-DAT, both animal species were submitted to two test sessions (3-h and 24-h) after the conditioning training. Proechimys exhibited higher anxiety-like behavior in the training session but during test sessions both species exhibited similar patterns of anxiety-related behavior. After 3-h of the training, Proechimys and Wistar spent significantly less time in the aversive enclosed arm than in the non-aversive arm. But, at 24-h after training, Wistar rats remained less time in the aversive closed arm in comparison with the non-aversive one, while Proechimys rodents spent the same amount of time in both enclosed arms. In the object recognition test, both species were evaluated at 24-h after the acquisition session and similar findings than those of the PM-DAT (24-h) were obtained, suggesting that long-term memory duration did not persist for 24-h in the Amazon rodent. Field excitatory post-synaptic potentials recordings revealed

Of trophies and pillars: exploring the terror management functions of short-term and long-term relationship partners.

PubMed

Kosloff, Spee; Greenberg, Jeff; Sullivan, Daniel; Weise, David

2010-08-01

Prior terror management research shows that mortality salience (MS) motivates both self-esteem striving and worldview bolstering. The present research examined these processes in the context of dating preferences. It was hypothesized that in short-term romantic contexts, MS-induced self-esteem striving motivates interest in dating a physically attractive other, whereas in long-term romantic contexts, MS-induced motives for worldview validation heighten interest in dating a same-religion other. Study 1 showed that in a short-term dating context, MS increased preference for an attractive but religiously dissimilar person, whereas in a long-term dating context, MS increased preference for a religiously similar, less attractive person. Study 2 clarified that MS motivates preference for attractive short-term partners for their self-enhancing properties rather than their potential sexual availability. Study 3 supported the theorized processes, showing that under MS, self-esteem-relevant constructs became spontaneously accessible in short-term dating contexts, whereas worldview-relevant constructs became spontaneously accessible in long-term dating contexts.

Do Firms Underinvest in Long-Term Research? Evidence from Cancer Clinical Trials.

PubMed

Budish, Eric; Roin, Benjamin N; Williams, Heidi

2015-07-01

We investigate whether private research investments are distorted away from long-term projects. Our theoretical model highlights two potential sources of this distortion: short-termism and the fixed patent term. Our empirical context is cancer research, where clinical trials--and hence, project durations--are shorter for late-stage cancer treatments relative to early-stage treatments or cancer prevention. Using newly constructed data, we document several sources of evidence that together show private research investments are distorted away from long-term projects. The value of life-years at stake appears large. We analyze three potential policy responses: surrogate (non-mortality) clinical-trial endpoints, targeted R&D subsidies, and patent design.

Do firms underinvest in long-term research? Evidence from cancer clinical trials.

PubMed

Budish, Eric; Roin, Benjamin N; Williams, Heidi

2015-07-01

We investigate whether private research investments are distorted away from long-term projects. Our theoretical model highlights two potential sources of this distortion: short-termism and the fixed patent term. Our empirical context is cancer research, where clinical trials - and hence, project durations - are shorter for late-stage cancer treatments relative to early-stage treatments or cancer prevention. Using newly constructed data, we document several sources of evidence that together show private research investments are distorted away from long-term projects. The value of life-years at stake appears large. We analyze three potential policy responses: surrogate (non-mortality) clinicaltrial endpoints, targeted R&D subsidies, and patent design.

Leptin attenuates the detrimental effects of β-amyloid on spatial memory and hippocampal later-phase long term potentiation in rats.

PubMed

Tong, Jia-Qing; Zhang, Jun; Hao, Ming; Yang, Ju; Han, Yu-Fei; Liu, Xiao-Jie; Shi, Hui; Wu, Mei-Na; Liu, Qing-Song; Qi, Jin-Shun

2015-07-01

β-Amyloid (Aβ) is the main component of amyloid plaques developed in the brain of patients with Alzheimer's disease (AD). The increasing burden of Aβ in the cortex and hippocampus is closely correlated with memory loss and cognition deficits in AD. Recently, leptin, a 16kD peptide derived mainly from white adipocyte tissue, has been appreciated for its neuroprotective function, although less is known about the effects of leptin on spatial memory and synaptic plasticity. The present study investigated the neuroprotective effects of leptin against Aβ-induced deficits in spatial memory and in vivo hippocampal late-phase long-term potentiation (L-LTP) in rats. Y maze spontaneous alternation was used to assess short term working memory, and the Morris water maze task was used to assess long term reference memory. Hippocampal field potential recordings were performed to observe changes in L-LTP. We found that chronically intracerebroventricular injection of leptin (1μg) effectively alleviated Aβ1-42 (20μg)-induced spatial memory impairments of Y maze spontaneous alternation and Morris water maze. In addition, chronic administration of leptin also reversed Aβ1-42-induced suppression of in vivo hippocampal L-LTP in rats. Together, these results suggest that chronic leptin treatments reversed Aβ-induced deficits in learning and memory and the maintenance of L-LTP. Copyright © 2015 Elsevier Inc. All rights reserved.

Improving long-term care provision: towards demand-based care by means of modularity

PubMed Central

2010-01-01

Background As in most fields of health care, societal and political changes encourage suppliers of long-term care to put their clients at the center of care and service provision and become more responsive towards client needs and requirements. However, the diverse, multiple and dynamic nature of demand for long-term care complicates the movement towards demand-based care provision. This paper aims to advance long-term care practice and, to that end, examines the application of modularity. This concept is recognized in a wide range of product and service settings for its ability to design demand-based products and processes. Methods Starting from the basic dimensions of modularity, we use qualitative research to explore the use and application of modularity principles in the current working practices and processes of four organizations in the field of long-term care for the elderly. In-depth semi-structured interviews were conducted with 38 key informants and triangulated with document research and observation. Data was analyzed thematically by means of coding and subsequent exploration of patterns. Data analysis was facilitated by qualitative analysis software. Results Our data suggest that a modular setup of supply is employed in the arrangement of care and service supply and assists providers of long-term care in providing their clients with choice options and variation. In addition, modularization of the needs assessment and package specification process allows the case organizations to manage client involvement but still provide customized packages of care and services. Conclusion The adequate setup of an organization's supply and its specification phase activities are indispensible for long-term care providers who aim to do better in terms of quality and efficiency. Moreover, long-term care providers could benefit from joint provision of care and services by means of modular working teams. Based upon our findings, we are able to elaborate on how to further

Improving long-term care provision: towards demand-based care by means of modularity.

PubMed

de Blok, Carolien; Luijkx, Katrien; Meijboom, Bert; Schols, Jos

2010-09-21

As in most fields of health care, societal and political changes encourage suppliers of long-term care to put their clients at the center of care and service provision and become more responsive towards client needs and requirements. However, the diverse, multiple and dynamic nature of demand for long-term care complicates the movement towards demand-based care provision. This paper aims to advance long-term care practice and, to that end, examines the application of modularity. This concept is recognized in a wide range of product and service settings for its ability to design demand-based products and processes. Starting from the basic dimensions of modularity, we use qualitative research to explore the use and application of modularity principles in the current working practices and processes of four organizations in the field of long-term care for the elderly. In-depth semi-structured interviews were conducted with 38 key informants and triangulated with document research and observation. Data was analyzed thematically by means of coding and subsequent exploration of patterns. Data analysis was facilitated by qualitative analysis software. Our data suggest that a modular setup of supply is employed in the arrangement of care and service supply and assists providers of long-term care in providing their clients with choice options and variation. In addition, modularization of the needs assessment and package specification process allows the case organizations to manage client involvement but still provide customized packages of care and services. The adequate setup of an organization's supply and its specification phase activities are indispensible for long-term care providers who aim to do better in terms of quality and efficiency. Moreover, long-term care providers could benefit from joint provision of care and services by means of modular working teams. Based upon our findings, we are able to elaborate on how to further enable demand-based provision of long-term

Long-term care financing: lessons from France.

PubMed

Doty, Pamela; Nadash, Pamela; Racco, Nathalie

2015-06-01

POLICY POINTS: France's model of third-party coverage for long-term services and supports (LTSS) combines a steeply income-adjusted universal public program for people 60 or older with voluntary supplemental private insurance. French and US policies differ: the former pay cash; premiums are lower; and take-up rates are higher, in part because employer sponsorship, with and without subsidization, is more common-but also because coverage targets higher levels of need and pays a smaller proportion of costs. Such inexpensive, bare-bones private coverage, especially if marketed as a supplement to a limited public benefit, would be more affordable to those Americans currently most at risk of "spending down" to Medicaid. An aging population leads to a growing demand for long-term services and supports (LTSS). In 2002, France introduced universal, income-adjusted, public long-term care coverage for adults 60 and older, whereas the United States funds means-tested benefits only. Both countries have private long-term care insurance (LTCI) markets: American policies create alternatives to out-of-pocket spending and protect purchasers from relying on Medicaid. Sales, however, have stagnated, and the market's viability is uncertain. In France, private LTCI supplements public coverage, and sales are growing, although its potential to alleviate the long-term care financing problem is unclear. We explore whether France's very different approach to structuring public and private financing for long-term care could inform the United States' long-term care financing reform efforts. We consulted insurance experts and conducted a detailed review of public reports, academic studies, and other documents to understand the public and private LTCI systems in France, their advantages and disadvantages, and the factors affecting their development. France provides universal public coverage for paid assistance with functional dependency for people 60 and older. Benefits are steeply income

Factors important in the purchase of partnership long-term care insurance.

PubMed

McCall, N; Mangle, S; Bauer, E; Knickman, J

1998-06-01

To understand the factors important in the purchase of long-term care insurance through the Robert Wood Johnson Foundation Partnership for Long-Term Care. Information on the Partnership programs, telephone surveys, data on Partnership purchasers, and random sample frames. Logistic regression analysis is used to examine characteristics associated with the purchase of a Partnership insurance policy. Independent variables are health status, demographic and financial characteristics, knowledge, and attitudes. A telephone survey of Partnership purchasers and a random sample of the population in each Partnership state were conducted. Survey questions included health status, opinions about long-term care and long-term care insurance, financial planning, demographic characteristics, and income and assets. Important in the purchase of a Partnership policy were variables associated with education and knowledge about long-term care. Other important factors include attitudes and health status. Partnership purchase is associated with higher income and asset levels up to a point, with the effect plateauing and decreasing at the highest income and asset levels. Improved education and knowledge are important in increasing long-term care insurance purchase. Attitudes about having a caregiver, and about the government's role in paying for long-term care as well as the potential purchaser's willingness to consider nursing home care affect policy purchase. Also associated with Partnership policy purchase are better health and middle income and asset levels.

Management training in long-term care.

PubMed

Evashwick, Connie

2002-01-01

The education of health care administrators faces its most dramatic change since the inception of the field. Recent discussions at the national level call for major overhaul of curricula and teaching modalities, including moving education to position students for evidence-based practice. This paper presents recommendations for incorporating training about chronic and long-term care into health care management curricula. It asserts that all health care management students should have a basic knowledge of the fundamental policy, operating, and financing principles of long-term care. The majority of people using the health care delivery system today, and increasingly in the future, suffer from chronic conditions. Long-term care services, although less expansive in structure, far outnumber acute care services and health plans. They will grow in the future to meet the portending demand. To maximize job opportunities and to optimize performance in any job, health care administrators need to know about the long-term care delivery system. This paper delineates critical topics pertaining to long-term care, organized according to 11 fundamental management areas in which the field is developing core competencies. The contents were derived from a year-long process of asking stakeholders in the various facets of long-term care what topics they thought were essential for administrators to know. The topics delineated in this document represent the consensus about essential knowledge that all health care administrators should have about long-term care, whether specializing in long-term care or following a more general management career. The education of health care administrators faces its most dramatic change since the inception ofthe field. Recent discussions at the national level call for major overhaul of curricula and teaching modalities, including moving education to position students to perform according to evidence-based practice. It is thus timely to consider content, as

Long-Term Pain and Recovery After Major Pediatric Surgery: A Qualitative Study With Teens, Parents, and Perioperative Care Providers.

PubMed

Rabbitts, Jennifer A; Aaron, Rachel V; Fisher, Emma; Lang, Emily A; Bridgwater, Caroline; Tai, Gabrielle Ghafari; Palermo, Tonya M

2017-07-01

Research developing targeted treatment focused on coping with children's long-term pain after surgery is needed because of the high prevalence of chronic pain after surgery. This qualitative study aimed to: 1) understand the child's and family's experiences of pain over the course of their surgical experience, and 2) gather stakeholder input regarding potential barriers and facilitators of perioperative intervention delivery. Fifteen children ages 10 to 18 years who underwent recent major surgery, their primary caregivers, and 17 perioperative health care providers were interviewed. Interviews were coded using semantic thematic analysis. The perioperative period presented emotional challenges for families. Families felt unprepared for surgery and pain. Recovery and regaining physical functioning at home was challenging. Families struggled to return to valued activities. Families reported interest in a perioperative psychosocial intervention. Providers endorsed that families would benefit from enhanced coping skills. They emphasized that families would benefit from more detailed preparatory information. Providers suggested that flexible intervention delivery at home would be ideal. Research developing interventions addressing pain and anxiety in children undergoing major surgery is critically needed. The findings of the present study can inform intervention development with the aim of improving short- as well as long-term recovery in children undergoing major surgery. This qualitative study examined children and their parents' experience of long-term pain and recovery after major surgery, identifying barriers and facilitators of perioperative intervention delivery. Families experienced surgery as stressful, and felt underprepared for pain and recovery. Families and health care providers expressed interest in a preoperative intervention teaching coping skills. Copyright © 2017 American Pain Society. Published by Elsevier Inc. All rights reserved.

Postfatigue potentiation of the paralyzed soleus muscle: evidence for adaptation with long-term electrical stimulation training

PubMed Central

Shields, Richard K.; Dudley-Javoroski, Shauna; Littmann, Andrew E.

2012-01-01

Understanding the torque output behavior of paralyzed muscle has important implications for the use of functional neuromuscular electrical stimulation systems. Postfatigue potentiation is an augmentation of peak muscle torque during repetitive activation after a fatigue protocol. The purposes of this study were 1) to quantify postfatigue potentiation in the acutely and chronically paralyzed soleus and 2) to determine the effect of long-term soleus electrical stimulation training on the potentiation characteristics of recently paralyzed soleus muscle. Five subjects with chronic paralysis (>2 yr) demonstrated significant postfatigue potentiation during a repetitive soleus activation protocol that induced low-frequency fatigue. Ten subjects with acute paralysis (<6 mo) demonstrated no torque potentiation in response to repetitive stimulation. Seven of these acute subjects completed 2 yr of home-based isometric soleus electrical stimulation training of one limb (compliance = 83%; 8,300 contractions/wk). With the early implementation of electrically stimulated training, potentiation characteristics of trained soleus muscles were preserved as in the acute postinjury state. In contrast, untrained limbs showed marked postfatigue potentiation at 2 yr after spinal cord injury (SCI). A single acute SCI subject who was followed longitudinally developed potentiation characteristics very similar to the untrained limbs of the training subjects. The results of the present investigation support that postfatigue potentiation is a characteristic of fast-fatigable muscle and can be prevented by timely neuromuscular electrical stimulation training. Potentiation is an important consideration in the design of functional electrical stimulation control systems for people with SCI. PMID:16575026

Postfatigue potentiation of the paralyzed soleus muscle: evidence for adaptation with long-term electrical stimulation training.

PubMed

Shields, Richard K; Dudley-Javoroski, Shauna; Littmann, Andrew E

2006-08-01

Understanding the torque output behavior of paralyzed muscle has important implications for the use of functional neuromuscular electrical stimulation systems. Postfatigue potentiation is an augmentation of peak muscle torque during repetitive activation after a fatigue protocol. The purposes of this study were 1) to quantify postfatigue potentiation in the acutely and chronically paralyzed soleus and 2) to determine the effect of long-term soleus electrical stimulation training on the potentiation characteristics of recently paralyzed soleus muscle. Five subjects with chronic paralysis (>2 yr) demonstrated significant postfatigue potentiation during a repetitive soleus activation protocol that induced low-frequency fatigue. Ten subjects with acute paralysis (<6 mo) demonstrated no torque potentiation in response to repetitive stimulation. Seven of these acute subjects completed 2 yr of home-based isometric soleus electrical stimulation training of one limb (compliance = 83%; 8,300 contractions/wk). With the early implementation of electrically stimulated training, potentiation characteristics of trained soleus muscles were preserved as in the acute postinjury state. In contrast, untrained limbs showed marked postfatigue potentiation at 2 yr after spinal cord injury (SCI). A single acute SCI subject who was followed longitudinally developed potentiation characteristics very similar to the untrained limbs of the training subjects. The results of the present investigation support that postfatigue potentiation is a characteristic of fast-fatigable muscle and can be prevented by timely neuromuscular electrical stimulation training. Potentiation is an important consideration in the design of functional electrical stimulation control systems for people with SCI.

Placenta previa and long-term morbidity of the term offspring.

PubMed

Walfisch, Asnat; Beharier, Ofer; Shoham-Vardi, Ilana; Sergienko, Ruslan; Landau, Daniella; Sheiner, Eyal

2016-08-01

The long-term impact of placenta previa on term infants is unknown. We aimed to investigate whether abnormal placentation increases the risk for long-term morbidity of the term offspring. A population-based cohort study compared the incidence of long-term hospitalizations up to the age of 18 due to cardiovascular, endocrine, neurological, hematological, respiratory and urinary morbidity of children born at term in pregnancies diagnosed with placenta previa and those without. Deliveries occurred between the years 1991-2013 in a tertiary medical center. Multiple pregnancies, and fetal congenital malformations were excluded. Kaplan-Meier survival curves were used to compare cumulative morbidity incidence over time. A multivariable generalized estimating equation (GEE) logistic regression model analysis was used to control for confounders and for maternal clusters. During the study period 233,123 term deliveries met the inclusion criteria; 0.2% (n=502) of the children were born to mothers with placenta previa. During the follow-up period, children born to mothers with placenta previa did not have an increased risk for long-term cardiovascular, endocrine, hematological, neurological, respiratory, and urinary morbidity. Term offsprings of mothers diagnosed with placenta previa do not appear to be at an increased risk for long-term morbidity up to the age of 18. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Long-term exposure to acidification disrupts reproduction in a marine invertebrate

PubMed Central

Hattich, Giannina S. I.; Heinrichs, Mara E.; Pansch, Andreas; Zagrodzka, Zuzanna; Havenhand, Jonathan N.

2018-01-01

Climate change research is advancing to more complex and more comprehensive studies that include long-term experiments, multiple life-history stages, multi-population, and multi-trait approaches. We used a population of the barnacle Balanus improvisus known to be sensitive to short-term acidification to determine its potential for long-term acclimation to acidification. We reared laboratory-bred individuals (as singles or pairs), and field-collected assemblages of barnacles, at pH 8.1 and 7.5 (≈ 400 and 1600 μatm pCO2 respectively) for up to 16 months. Acidification caused strong mortality and reduced growth rates. Acidification suppressed respiration rates and induced a higher feeding activity of barnacles after 6 months, but this suppression of respiration rate was absent after 15 months. Laboratory-bred barnacles developed mature gonads only when they were held in pairs, but nonetheless failed to produce fertilized embryos. Field-collected barnacles reared in the laboratory for 8 months at the same pH’s developed mature gonads, but only those in pH 8.1 produced viable embryos and larvae. Because survivors of long-term acidification were not capable of reproducing, this demonstrates that B. improvisus can only partially acclimate to long-term acidification. This represents a clear and significant bottleneck in the ontogeny of this barnacle population that may limit its potential to persist in a future ocean. PMID:29408893

Identifying the potential long-term survivors among breast cancer patients with distant metastasis.

PubMed

Lee, E S; Jung, S Y; Kim, J Y; Kim, J J; Yoo, T K; Kim, Y G; Lee, K S; Lee, E S; Kim, E K; Min, J W; Han, W; Noh, D Y; Moon, H G

2016-05-01

We aimed to develop a prediction model to identify long-term survivors after developing distant metastasis from breast cancer. From the institution's database, we collected data of 547 patients who developed distant metastasis during their follow-ups. We developed a model that predicts the post-metastasis overall survival (PMOS) based on the clinicopathologic factors of the primary tumors and the characteristics of the distant metastasis. For validation, the survival data of 254 patients from four independent institutions were used. The median duration of the PMOS was 31.0 months. The characteristics of the initial primary tumor, such as tumor stage, hormone receptor status, and Ki-67 expression level, and the characteristics of the distant metastasis presentation including the duration of disease-free interval, the site of metastasis, and the presence of metastasis-related symptoms were independent prognostic factors determining the PMOS. The association between tumor stage and the PMOS was only seen in tumors with early relapses. The PMOS score, which was developed based on the above six factors, successfully identified patients with superior survival after metastasis. The median PMOS for patients with a PMOS score of <2 and for patients with a PMOS score of >5 were 71.0 and 12 months, respectively. The clinical significance of the PMOS score was further validated using independent multicenter datasets. We have developed a novel prediction model that can classify breast cancer patients with distant metastasis according to their survival after metastasis. Our model can be a valuable tool to identify long-term survivors who can be potential candidates for more intensive multidisciplinary approaches. Furthermore, our model can provide a more reliable survival information for both physicians and patients during their informed decision-making process. © The Author 2016. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All

Short-term versus long-term rainfall time series in the assessment of potable water savings by using rainwater in houses.

PubMed

Ghisi, Enedir; Cardoso, Karla Albino; Rupp, Ricardo Forgiarini

2012-06-15

The main objective of this article is to assess the possibility of using short-term instead of long-term rainfall time series to evaluate the potential for potable water savings by using rainwater in houses. The analysis was performed considering rainfall data from 1960 to 1995 for the city of Santa Bárbara do Oeste, located in the state of São Paulo, southeastern Brazil. The influence of the rainfall time series, roof area, potable water demand and percentage rainwater demand on the potential for potable water savings was evaluated. The potential for potable water savings was estimated using computer simulations considering a set of long-term rainfall time series and different sets of short-term rainfall time series. The ideal rainwater tank capacity was also assessed for some cases. It was observed that the higher the percentage rainwater demand and the shorter the rainfall time series, the larger the difference between the potential for potable water savings and the greater the variation in the ideal rainwater tank size. The sets of short-term rainfall time series considered adequate for different scenarios ranged from 1 to 13 years depending on the roof area, percentage rainwater demand and potable water demand. The main finding of the research is that sets of short-term rainfall time series can be used to assess the potential for potable water savings by using rainwater, as the results obtained are similar to those obtained from the long-term rainfall time series. Copyright © 2012 Elsevier Ltd. All rights reserved.

eLearning, knowledge brokering, and nursing: strengthening collaborative practice in long-term care.

PubMed

Halabisky, Brenda; Humbert, Jennie; Stodel, Emma J; MacDonald, Colla J; Chambers, Larry W; Doucette, Suzanne; Dalziel, William B; Conklin, James

2010-01-01

Interprofessional collaboration is vital to the delivery of quality care in long-term care settings; however, caregivers in long-term care face barriers to participating in training programs to improve collaborative practices. Consequently, eLearning can be used to create an environment that combines convenient, individual learning with collaborative experiential learning. Findings of this study revealed that learners enjoyed the flexibility of the Working Together learning resource. They acquired new knowledge and skills that they were able to use in their practice setting to achieve higher levels of collaborative practice. Nurses were identified as team leaders because of their pivotal role in the long-term care home and collaboration with all patient care providers. Nurses are ideal as knowledge brokers for the collaborative practice team. Quantitative findings showed no change in learner's attitudes regarding collaborative practice; however, interviews provided examples of positive changes experienced. Face-to-face collaboration was found to be a challenge, and changes to organizations, systems, and technology need to be made to facilitate this process. The Working Together learning resource is an important first step toward strengthening collaboration in long-term care, and the pilot implementation provides insights that further our understanding of both interprofessional collaboration and effective eLearning.

Developing a long-term condition's information service in collaboration with third sector organisations.

PubMed

McShane, Lesley; Greenwell, Kate; Corbett, Sally; Walker, Richard

2014-06-01

People with long-term conditions need to be signposted to high quality information and advice to understand and manage their condition. Information seeking tools combined with third sector information could help address their information needs. To describe the development and implementation of an information service for people living with long-term conditions at one NHS acute trust in the Northeast of England. An information service was trialled using bespoke information models for three long-term conditions in collaboration with third sector organisations. These guided people to relevant, timely and reliable information. Both clinician and service user questionnaires were used to evaluate satisfaction with the service. Appropriately designed information models can be used interchangeably across all services. Between 75% and 91% of users agreed that they were satisfied with various aspects of the service. Generally, users received relevant, understandable and high quality information at the right time. Nearly all health professionals (94-100%) felt the service was accessible, provided high quality information and did not significantly impact on their consultation time. The developed information service was well received by service users and health professionals. Specifically, the use of information prescriptions and menus facilitated access to information for people with long-term conditions. © 2014 The authors. Health Information and Libraries Journal © 2014 Health Libraries Group.

The Association between Physical Activity During the Day and Long-Term Memory Stability.

PubMed

Pontifex, Matthew B; Gwizdala, Kathryn L; Parks, Andrew C; Pfeiffer, Karin A; Fenn, Kimberly M

2016-12-02

Despite positive associations between chronic physical activity and memory; we have little understanding of how best to incorporate physical activity during the day to facilitate the consolidation of information into memory, nor even how time spent physically active during the day relates to memory processes. The purpose of this investigation was to examine the relation between physical activity during the day and long-term memory. Ninety-two young adults learned a list of paired-associate items and were tested on the items after a 12-hour interval during which heart rate was recorded continuously. Although the percentage of time spent active during the day was unrelated to memory, two critical physical activity periods were identified as relating to the maintenance of long-term memory. Engaging in physical activity during the period 1 to 2-hours following the encoding of information was observed to be detrimental to the maintenance of information in long-term memory. In contrast, physical activity during the period 1-hour prior to memory retrieval was associated with superior memory performance, likely due to enhanced retrieval processing. These findings provide initial evidence to suggest that long-term memory may be enhanced by more carefully attending to the relative timing of physical activity incorporated during the day.

Phenomenological and molecular-level Petri net modeling and simulation of long-term potentiation.

PubMed

Hardy, S; Robillard, P N

2005-10-01

Petri net-based modeling methods have been used in many research projects to represent biological systems. Among these, the hybrid functional Petri net (HFPN) was developed especially for biological modeling in order to provide biologists with a more intuitive Petri net-based method. In the literature, HFPNs are used to represent kinetic models at the molecular level. We present two models of long-term potentiation previously represented by differential equations which we have transformed into HFPN models: a phenomenological synapse model and a molecular-level model of the CaMKII regulation pathway. Through simulation, we obtained results similar to those of previous studies using these models. Our results open the way to a new type of modeling for systems biology where HFPNs are used to combine different levels of abstraction within one model. This approach can be useful in fully modeling a system at the molecular level when kinetic data is missing or when a full study of a system at the molecular level it is not within the scope of the research.

Reinstatement of long-term memory following erasure of its behavioral and synaptic expression in Aplysia

PubMed Central

Chen, Shanping; Cai, Diancai; Pearce, Kaycey; Sun, Philip Y-W; Roberts, Adam C; Glanzman, David L

2014-01-01

Long-term memory (LTM) is believed to be stored in the brain as changes in synaptic connections. Here, we show that LTM storage and synaptic change can be dissociated. Cocultures of Aplysia sensory and motor neurons were trained with spaced pulses of serotonin, which induces long-term facilitation. Serotonin (5HT) triggered growth of new presynaptic varicosities, a synaptic mechanism of long-term sensitization. Following 5HT training, two antimnemonic treatments—reconsolidation blockade and inhibition of PKM—caused the number of presynaptic varicosities to revert to the original, pretraining value. Surprisingly, the final synaptic structure was not achieved by targeted retraction of the 5HT-induced varicosities but, rather, by an apparently arbitrary retraction of both 5HT-induced and original synapses. In addition, we find evidence that the LTM for sensitization persists covertly after its apparent elimination by the same antimnemonic treatments that erase learning-related synaptic growth. These results challenge the idea that stable synapses store long-term memories. DOI: http://dx.doi.org/10.7554/eLife.03896.001 PMID:25402831

Long-Term Control Medications for Lung Diseases

MedlinePlus

... Asthma Medications Long-Term Control Medications Long-Term Control Medications Make an Appointment Ask a Question Refer Patient Long-term control medications are taken daily to control and prevent ...

Tolerance of Ruppia sinensis Seeds to Desiccation, Low Temperature, and High Salinity With Special Reference to Long-Term Seed Storage.

PubMed

Gu, Ruiting; Zhou, Yi; Song, Xiaoyue; Xu, Shaochun; Zhang, Xiaomei; Lin, Haiying; Xu, Shuai; Yue, Shidong; Zhu, Shuyu

2018-01-01

Seeds are important materials for the restoration of globally-threatened marine angiosperm (seagrass) populations. In this study, we investigated the differences between different Ruppia sinensis seed types and developed two feasible long-term R. sinensis seed storage methods. The ability of R. sinensis seeds to tolerate the short-term desiccation and extreme cold had been investigated. The tolerance of R. sinensis seeds to long-term exposure of high salinity, cold temperature, and desiccation had been considered as potential methods for long-term seed storage. Also, three morphological and nine physiological indices were measured and compared between two types of seeds: Shape L and Shape S. We found that: (1) wet storage at a salinity of 30-40 psu and 0°C were the optimal long-term storage conditions, and the proportion of viable seeds reached over 90% after a storage period of 11 months since the seeds were collected from the reproductive shoots; (2) dry condition was not the optimal choice for long-term storage of R. sinensis seeds; however, storing seeds in a dry condition at 5°C and 33 ± 10% relative humidity for 9 months had a relatively high percentage (74.44 ± 2.22%) of viable seeds, consequently desiccation exposure could also be an acceptable seed storage method; (3) R. sinensis seeds would lose vigor in the interaction of extreme cold (-27°C) and desiccation; (4) there were significant differences in seed weight, seed curvature, and endocarp thickness between the two types of seeds. These findings provided fundamental physiological information for R. sinensis seeds and supported the long-term storage of its seeds. Our results may also serve as useful reference for seed storage of other threatened seagrass species and facilitate their ex situ conservation and habitat restoration.

A Power-Efficient Bio-Potential Acquisition Device with DS-MDE Sensors for Long-Term Healthcare Monitoring Applications

PubMed Central

Chang, Chia-Lin; Chang, Chih-Wei; Huang, Hong-Yi; Hsu, Chen-Ming; Huang, Chia-Hsuan; Chiou, Jin-Chern; Luo, Ching-Hsing

2010-01-01

This work describes a power-efficient bio-potential acquisition device for long-term healthcare applications that is implemented using novel microelectromechanical dry electrodes (MDE) and a low power bio-potential processing chip. Using micromachining technology, an attempt is also made to enhance the sensing reliability and stability by fabricating a diamond-shaped MDE (DS-MDE) that has a satisfactory self-stability capability and superior electric conductivity when attached onto skin without any extra skin tissue injury technology. To acquire differential bio-potentials such as ECG signals, the proposed processing chip fabricated in a standard CMOS process has a high common mode rejection ratio (C.M.R.R.) differential amplifier and a 12-bit analog-to-digital converter (ADC). Use of the proposed system and integrate simple peripheral commercial devices can obtain the ECG signal efficiently without additional skin tissue injury and ensure continuous monitoring more than 70 hours with a 400 mAh battery. PMID:22399907

A power-efficient bio-potential acquisition device with DS-MDE sensors for long-term healthcare monitoring applications.

PubMed

Chang, Chia-Lin; Chang, Chih-Wei; Huang, Hong-Yi; Hsu, Chen-Ming; Huang, Chia-Hsuan; Chiou, Jin-Chern; Luo, Ching-Hsing

2010-01-01

This work describes a power-efficient bio-potential acquisition device for long-term healthcare applications that is implemented using novel microelectromechanical dry electrodes (MDE) and a low power bio-potential processing chip. Using micromachining technology, an attempt is also made to enhance the sensing reliability and stability by fabricating a diamond-shaped MDE (DS-MDE) that has a satisfactory self-stability capability and superior electric conductivity when attached onto skin without any extra skin tissue injury technology. To acquire differential bio-potentials such as ECG signals, the proposed processing chip fabricated in a standard CMOS process has a high common mode rejection ratio (C.M.R.R.) differential amplifier and a 12-bit analog-to-digital converter (ADC). Use of the proposed system and integrate simple peripheral commercial devices can obtain the ECG signal efficiently without additional skin tissue injury and ensure continuous monitoring more than 70 hours with a 400 mAh battery.

Nano-CuO impairs spatial cognition associated with inhibiting hippocampal long-term potentiation via affecting glutamatergic neurotransmission in rats.

PubMed

Li, Xiaoliang; Sun, Wei; An, Lei

2018-06-01

Manufactured metal nanoparticles and their applications are continuously expanding because of their unique characteristics while their increasing use may predispose to potential health problems. Several studies have reported the adverse effects of copper oxide nanoparticles (nano-CuO) relative to ecotoxicity and cell toxicity, whereas little is known about the neurotoxicity of nano-CuO. The present study aimed to examine its effects on spatial cognition, hippocampal function, and the possible mechanisms. Male Wistar rats were used to establish an animal model, and nano-CuO was administered at a dose of 0.5 mg/kg/day for 2 weeks. The Morris water maze (MWM) test was employed to evaluate learning and memory. The long-term potentiation (LTP) from Schaffer collaterals to the hippocampal CA1 region, and the effects of nano-CuO on synases were recorded in the hippocampal CA1 neurons of rats. MWM test showed that learning and memory abilities were impaired significantly by nano-CuO ( p < 0.05). The LTP test demonstrated that the field excitatory postsynaptic potential (fEPSP) slopes were significantly lower in nano-CuO-treated groups compared with the control group ( p < 0.01). Furthermore, the data of whole-cell patch-clamp experiments showed that nano-CuO markedly depressed the frequencies of both spontaneous excitatory postsynaptic currents (sEPSCs) and miniature EPSCs (mEPSCs), indicating an effect of nano-CuO on inhibiting the release frequency of glutamate presynapticly ( p < 0.01). Meanwhile, the amplitudes of both sEPSC and mEPSC were significantly reduced in nano-CuO-treated animals, which suggested that the effect of nano-CuO modulates postsynaptic receptor kinetics ( p < 0.01). Paired pulse facilitation (PPF) ( p < 0.05) and the expression of NR2A, but not NR2B, of N-methyl-d-aspartate (NMDA) subunits ( p < 0.05), were decreased significantly. In conclusion, nano-CuO impaired glutamate transmission presynapticly and postsynapticly, which may contribute

Reforming Long-Term Care Funding in Alberta.

PubMed

Crump, R Trafford; Repin, Nadya; Sutherland, Jason M

2015-01-01

Like many provinces across Canada, Alberta is facing growing demand for long-term care. Issues with the mixed funding model used to pay long-term care providers had Alberta Health Services concerned that it was not efficiently meeting the demand for long-term care. Consequently, in 2010, Alberta Health Services introduced the patient/care-based funding (PCBF) model. PCBF is similar to activity-based funding in that it directly ties the complexity and care needs of long-term care residents to the payment received by long-term care providers. This review describes PCBF and discusses some of its strengths and weaknesses. In doing so, this review is intended to inform other provinces faced with similar long-term care challenges and contemplating their own funding reforms.

Protein kinase M ζ and the maintenance of long-term memory.

PubMed

Zhang, Yang; Zong, Wei; Zhang, Lei; Ma, Yuanye; Wang, Jianhong

2016-10-01

Although various molecules have been found to mediate the processes of memory acquisition and consolidation, the molecular mechanism to maintain memory still remains elusive. In recent years, a molecular pathway focusing on protein kinase Mζ (PKMζ) has become of interest to researchers because of its potential role in long-term memory maintenance. PKMζ is an isoform of protein kinase C (PKC) and has a related structure that influences its function in maintaining memory. Considerable evidence has been gathered on PKMζ activity, including loss of function studies using PKMζ inhibitors, such as PKMζ inhibitory peptide (ZIP), suggesting PKMζ plays an important role in long-term memory maintenance. This review provides an overview of the role of PKMζ in long-term memory and outlines the molecular structure of PKMζ, the molecular mechanism of PKMζ in long-term memory maintenance and future directions of PKMζ research. Copyright © 2016 Elsevier Ltd. All rights reserved.

Individual decision making in the non-purchase of long-term care insurance.

PubMed

Curry, Leslie A; Robison, Julie; Shugrue, Noreen; Keenan, Patricia; Kapp, Marshall B

2009-08-01

Although prior research suggests that economic, behavioral, and psychosocial factors influence decisions not to purchase long-term care insurance, few studies have examined the interplay among these factors in depth and from the consumer's point of view. This study was intended to further illuminate these considerations, generate hypotheses about non-purchasing decisions, and inform the design of policies that are responsive to concerns and preferences of potential purchasers. Qualitative study using 32 in-depth interviews and 6 focus groups, following a grounded theory approach. Five themes characterize decisions not to purchase long-term care insurance: (a) the determination that a policy is "too costly" reflects highly individualized and complex trade-offs not solely economic in nature, (b) non-purchasers are skeptical about the viability and integrity of private insurance companies and seek an unbiased source of information, (c) family dynamics play an important role in insurance decisions, (d) contemplating personal risk for long-term care triggers psychological responses that have implications for decision making, and (e) non-purchasers feel inadequately informed and overwhelmed by the process of deciding whether to purchase long-term care insurance. States are seeking to offset escalating Medicaid long-term care expenditures through a variety of policy mechanisms, including stimulating individual purchase of long-term care insurance. Findings suggest that economic incentives such as lowering premiums will be necessary but not sufficient to attract appropriate candidates. Attention to behavioral and psychosocial factors is essential to designing incentives that are responsive to concerns and preferences of potential purchasers.

“Going Episodic”: Collaborative Inhibition and Facilitation When Long-Married Couples Remember Together

PubMed Central

Harris, Celia B.; Barnier, Amanda J.; Sutton, John; Keil, Paul G.; Dixon, Roger A.

2017-01-01

Two complementary approaches to the study of collaborative remembering have produced contrasting results. In the experimental “collaborative recall” approach within cognitive psychology, collaborative remembering typically results in ‘collaborative inhibition’: laboratory groups recall fewer items than their estimated potential. In the cognitive ageing approach, collaborative remembering with a partner or spouse may provide cuing and support to benefit older adults’ performance on everyday memory tasks. To combine the value of experimental and cognitive ageing approaches, we tested the effects of collaborative remembering in older, long-married couples who recalled a non-personal word list and a personal semantic list of shared trips. We scored amount recalled as well as the kinds of details remembered. We found evidence for collaborative inhibition across both tasks when scored strictly as number of list items recalled. However, we found collaborative facilitation of specific episodic details on the personal semantic list, details which were not strictly required for the completion of the task. In fact, there was a trade-off between recall of specific episodic details and number of trips recalled during collaboration. We discuss these results in terms of the functions of shared remembering and what constitutes memory success, particularly for intimate groups and for older adults. PMID:28071300

Viability of long-term gene therapy in the cochlea.

PubMed

Atkinson, Patrick J; Wise, Andrew K; Flynn, Brianna O; Nayagam, Bryony A; Richardson, Rachael T

2014-04-22

Gene therapy has been investigated as a way to introduce a variety of genes to treat neurological disorders. An important clinical consideration is its long-term effectiveness. This research aims to study the long-term expression and effectiveness of gene therapy in promoting spiral ganglion neuron survival after deafness. Adenoviral vectors modified to express brain derived neurotrophic factor or neurotrophin-3 were unilaterally injected into the guinea pig cochlea one week post ototoxic deafening. After six months, persistence of gene expression and significantly greater neuronal survival in neurotrophin-treated cochleae compared to the contralateral cochleae were observed. The long-term gene expression observed indicates that gene therapy is potentially viable; however the degeneration of the transduced cells as a result of the original ototoxic insult may limit clinical effectiveness. With further research aimed at transducing stable cochlear cells, gene therapy may be an efficacious way to introduce neurotrophins to promote neuronal survival after hearing loss.

Do firms underinvest in long-term research? Evidence from cancer clinical trials

PubMed Central

Budish, Eric; Roin, Benjamin N.

2015-01-01

We investigate whether private research investments are distorted away from long-term projects. Our theoretical model highlights two potential sources of this distortion: short-termism and the fixed patent term. Our empirical context is cancer research, where clinical trials – and hence, project durations – are shorter for late-stage cancer treatments relative to early-stage treatments or cancer prevention. Using newly constructed data, we document several sources of evidence that together show private research investments are distorted away from long-term projects. The value of life-years at stake appears large. We analyze three potential policy responses: surrogate (non-mortality) clinicaltrial endpoints, targeted R&D subsidies, and patent design. PMID:26345455

Long-term sensitization training in Aplysia leads to an increase in the expression of BiP, the major protein chaperon of the ER.

PubMed

Kuhl, D; Kennedy, T E; Barzilai, A; Kandel, E R

1992-12-01

Long-term memory for sensitization of the gill- and siphon-withdrawal reflexes in Aplysia californica requires RNA and protein synthesis. These long-term behavioral changes are accompanied by long-term facilitation of the synaptic connections between the gill and siphon sensory and motor neurons, which are similarly dependent on transcription and translation. In addition to showing an increase in over-all protein synthesis, long-term facilitation is associated with changes in the expression of specific early, intermediate, and late proteins, and with the growth of new synaptic connections between the sensory and motor neurons of the reflex. We previously focused on early proteins and have identified four proteins as members of the immunoglobulin family of cell adhesion molecules related to NCAM and fasciclin II. We have now cloned the cDNA corresponding to one of the late proteins, and identified it as the Aplysia homolog of BiP, an ER resident protein involved in the folding and assembly of secretory and membrane proteins. Behavioral training increases the steady-state level of BiP mRNA in the sensory neurons. The increase in the synthesis of BiP protein is first detected 3 h after the onset of facilitation, when the increase in overall protein synthesis reaches its peak and the formation of new synaptic terminals becomes apparent. These findings suggest that the chaperon function of BiP might serve to fold proteins and assemble protein complexes necessary for the structural changes characteristic of long-term memory.

Going Solar Yields Long-Term Economical, Educational Benefits

ERIC Educational Resources Information Center

von Moos, Brian

2009-01-01

Going solar is not an easy decision, but a long-term investment with a potentially substantial up-front cost. While some schools have enough capital in reserve, can raise bond money, or can solicit sufficient donations, many schools rely on creative financial programs to make a solar energy system economically feasible. Thinking about going solar…

Long-Term Monitoring Research Needs: A DOE Perspective

NASA Astrophysics Data System (ADS)

Moore, B.; Davis, C. B.

2002-05-01

critically on the validity and uncertainty in models used to predict contaminant fate and transport. This is an area of active research at the present time. We survey joint research initiatives in this area involving DOE along with USGS, U.S. EPA, U.S. NRC, and U.S. DOA and non-Federal collaborators, and explore their potential for furthering DOE long-term monitoring needs and objectives.

Volunteer provision of long-term care for older people in Thailand and Costa Rica.

PubMed

Lloyd-Sherlock, Peter; Pot, Anne Margriet; Sasat, Siriphan; Morales-Martinez, Fernando

2017-11-01

Demand for long-term care services for older people is increasing rapidly in low- and middle-income countries. Countries need to establish national long-term care systems that are sustainable and equitable. The Governments of Costa Rica and Thailand have implemented broadly comparable interventions to deploy volunteers in long-term home care. Both countries trained older volunteers from local communities to make home visits to impoverished and vulnerable older people and to facilitate access to health services and other social services. Costa Rica and Thailand are upper-middle-income countries with strong traditions of community-based health services that they are now extending into long-term care for older people. Between 2003 and 2013 Thailand's programme trained over 51 000 volunteers, reaching almost 800 000 older people. Between 2010 and 2016 Costa Rica established 50 community care networks, serving around 10 000 people and involving over 5000 volunteers. Despite some evidence of benefits to the physical and mental health of older people and greater uptake of other services, a large burden of unmet care needs and signs of a growth of unregulated private services still exist. There is scope for low- and middle-income countries to develop large-scale networks of community-based long-term care volunteers. The capacity of volunteers to enhance the quality of life of clients is affected by the local availability of care services. Volunteer care networks should be complemented by other initiatives, including training about health in later life for volunteers, and investment in community long-term care services.

Long-Term Research in Ecology and Evolution (LTREE): 2015 survey data.

PubMed

Bradford, Mark A; Leiserowitz, Anthony; Feinberg, Geoffrey; Rosenthal, Seth A; Lau, Jennifer A

2017-11-01

To systematically assess views on contributions and future activities for long-term research in ecology and evolution (LTREE), we conducted and here provide data responses and associated metadata for a survey of ecological and evolutionary scientists. The survey objectives were to: (1) Identify and prioritize research questions that are important to address through long-term, ecological field experiments; and (2) understand the role that these experiments might play in generating and applying ecological and evolutionary knowledge. The survey was developed adhering to the standards of the American Association for Public Opinion Research. It was administered online using Qualtrics Survey Software. Survey creation was a multi-step process, with questions and format developed and then revised with, for example, input from an external advisory committee comprising senior and junior ecological and evolutionary researchers. The final questionnaire was released to ~100 colleagues to ensure functionality and then fielded 2 d later (January 7 th , 2015). Two professional societies distributed it to their membership, including the Ecological Society of America, and it was posted to three list serves. The questionnaire was available through February 8th 2015 and completed by 1,179 respondents. The distribution approach targeted practicing ecologists and evolutionary biologists in the U.S. Quantitative (both ordinal and categorical) closed-ended questions used a predefined set of response categories, facilitating direct comparison across all respondents. Qualitative, open-ended questions, provided respondents the opportunity to develop their own answers. We employed quantitative questions to score views on the extent to which long-term experimental research has contributed to understanding in ecology and evolutionary biology; its role compared to other approaches (e.g., short-term experiments); justifications for and caveats to long-term experiments; and the relative importance

Long-term impact of precision agriculture on a farmer’s field

USDA-ARS?s Scientific Manuscript database

Targeting management practices and inputs with precision agriculture has high potential to meet some of the grand challenges of sustainability in the coming century. Although potential is high, few studies have documented long-term effects of precision agriculture on crop production and environmenta...

The Long-Term Budget Outlook

DTIC Science & Technology

2005-12-01

Revenues Under CBO’s Long-Term Budget Scenarios 56A-8. Real Gross Domestic Product Under CBO’s Long-Term Budget Scenarios 57A-9. Total Surplus or...scenarios suggest that total federal spending for Medicare and Medicaid in 2050 could range anywhere from 7 percent of gross domestic product (GDP)—a...see the Congressional Budget Office’s glossary of budgetary and economic terms, available at www.cbo.gov. 2. The future path of productivity growth

The long-term psychiatric and medical prognosis of perinatal mental illness.

PubMed

Meltzer-Brody, Samantha; Stuebe, Alison

2014-01-01

The perinatal period provides an important window into a woman's long-term health. Perinatal mental illness is a common condition conferring potential serious long-term psychiatric and medical consequences for the mother and family. It is known that childbirth acts as a powerful trigger for depressive episodes in some women, and that women with histories of a mood disorder are particularly vulnerable. Some evidence links perinatal mental illness with obstetrical complications and reduced lactation initiation and duration. Therefore, perinatal mental illness may be a marker for long-term risk, and may contribute directly to subsequent cardiometabolic disease through both neuroendocrine mechanisms and the effects of mental illness on health behaviours. In clinical practice, these associations underscore the importance of screening and treating women with perinatal mental illness to ensure best possible long-term outcomes. Early screening and treatment may both mitigate the primary disease process and reduce the risk of comorbid medical conditions. Copyright © 2013 Elsevier Ltd. All rights reserved.

Acute inhibition of estradiol synthesis impacts vestibulo-ocular reflex adaptation and cerebellar long-term potentiation in male rats.

PubMed

Dieni, Cristina V; Ferraresi, Aldo; Sullivan, Jacqueline A; Grassi, Sivarosa; Pettorossi, Vito E; Panichi, Roberto

2018-03-01

The vestibulo-ocular reflex (VOR) adaptation is an ideal model for investigating how the neurosteroid 17 beta-estradiol (E2) contributes to the modification of behavior by regulating synaptic activities. We hypothesized that E2 impacts VOR adaptation by affecting cerebellar synaptic plasticity at the parallel fiber-Purkinje cell (PF) synapse. To verify this hypothesis, we investigated the acute effect of blocking E2 synthesis on gain increases and decreases in adaptation of the VOR in male rats using an oral dose (2.5 mg/kg) of the aromatase inhibitor letrozole. We also assessed the effect of letrozole on synaptic plasticity at the PF synapse in vitro, using cerebellar slices from male rats. We found that letrozole acutely impaired both gain increases and decreases adaptation of the VOR without altering basal ocular-motor performance. Moreover, letrozole prevented long-term potentiation at the PF synapse (PF-LTP) without affecting long-term depression (PF-LTD). Thus, in male rats neurosteroid E2 has a relevant impact on VOR adaptation and affects exclusively PF-LTP. These findings suggest that E2 might regulate changes in VOR adaptation by acting locally on cerebellar and extra-cerebellar synaptic plasticity sites.

Long-term bed degradation in Maryland streams (phase 2) : Blue Ridge and western Piedmont provinces [research summary].

DOT National Transportation Integrated Search

2012-03-01

Problem: : Estimation of potential long-term down-cutting of the stream bed is necessary for evaluation and design of bridges for scour and culverts for fish passage. Existing guidelines for assessing this potential long-term bed degradation (LTBD) i...

Long-term outcomes after severe shock.

PubMed

Pratt, Cristina M; Hirshberg, Eliotte L; Jones, Jason P; Kuttler, Kathryn G; Lanspa, Michael J; Wilson, Emily L; Hopkins, Ramona O; Brown, Samuel M

2015-02-01

Severe shock is a life-threatening condition with very high short-term mortality. Whether the long-term outcomes among survivors of severe shock are similar to long-term outcomes of other critical illness survivors is unknown. We therefore sought to assess long-term survival and functional outcomes among 90-day survivors of severe shock and determine whether clinical predictors were associated with outcomes. Seventy-six patients who were alive 90 days after severe shock (received ≥1 μg/kg per minute of norepinephrine equivalent) were eligible for the study. We measured 3-year survival and long-term functional outcomes using the Medical Outcomes Study 36-Item Short-Form Health Survey, the EuroQOL 5-D-3L, the Hospital Anxiety and Depression Scale, the Impact of Event Scale-Revised, and an employment instrument. We also assessed the relationship between in-hospital predictors and long-term outcomes. The mean long-term survival was 5.1 years; 82% (62 of 76) of patients survived, of whom 49 were eligible for follow-up. Patients who died were older than patients who survived. Thirty-six patients completed a telephone interview a mean of 5 years after hospital admission. The patients' Physical Functioning scores were below U.S. population norms (P < 0.001), whereas mental health scores were similar to population norms. Nineteen percent of the patients had symptoms of depression, 39% had symptoms of anxiety, and 8% had symptoms of posttraumatic stress disorder. Thirty-six percent were disabled, and 17% were working full-time. Early survivors of severe shock had a high 3-year survival rate. Patients' long-term physical and psychological outcomes were similar to those reported for cohorts of less severely ill intensive care unit survivors. Anxiety and depression were relatively common, but only a few patients had symptoms of posttraumatic stress disorder. This study supports the observation that acute illness severity does not determine long-term outcomes. Even extremely

Sauroxine reduces memory retention in rats and impairs hippocampal long-term potentiation generation.

PubMed

Vallejo, Mariana; Carlini, Valeria; Gabach, Laura; Ortega, M G; L Cabrera, José; de Barioglio, Susana Rubiales; Pérez, Mariela; Agnese, Alicia M

2017-07-01

In the present paper it was investigated the role of sauroxine, an alkaloid of Phlegmariurus saururus, as a modulator of some types of learning and memory, considering the potential nootropic properties previously reported for the alkaloid extract and the main alkaloid sauroine. Sauroxine was isolated by means of an alkaline extraction, purified by several chromatographic techniques, and assayed in electrophysiological experiments on rat hippocampus slices, tending towards the elicitation of the long-term potentiation (LTP) phenomena. It was also studied the effects of intrahippocampal administration of sauroxine on memory retention in vivo using a Step-down test. Being the bio distribution of a drug an important parameter to be considered, the concentration of sauroxine in rat brain was determined by GLC-MS. Sauroxine blocked LTP generation at both doses used, 3.65 and 3.610 -2 μM. In the behavioral test, the animals injected with this alkaloid (3.6510 -3 nmol) exhibited a significant decrease on memory retention compared with control animals. It was also showed that sauroxine reached the brain (3.435μg/g tissue), after an intraperitoneal injection, displaying its ability to cross the blood-brain barrier. Thus, sauroxine demonstrated to exert an inhibition on these mnemonic phenomena. The effect here established for 1 is defeated by other constituents according to the excellent results obtained for P. saururus alkaloid extract as well as for the isolated alkaloid sauroine. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Astrocyte-neuron lactate transport is required for long-term memory formation.

PubMed

Suzuki, Akinobu; Stern, Sarah A; Bozdagi, Ozlem; Huntley, George W; Walker, Ruth H; Magistretti, Pierre J; Alberini, Cristina M

2011-03-04

We report that, in the rat hippocampus, learning leads to a significant increase in extracellular lactate levels that derive from glycogen, an energy reserve selectively localized in astrocytes. Astrocytic glycogen breakdown and lactate release are essential for long-term but not short-term memory formation, and for the maintenance of long-term potentiation (LTP) of synaptic strength elicited in vivo. Disrupting the expression of the astrocytic lactate transporters monocarboxylate transporter 4 (MCT4) or MCT1 causes amnesia, which, like LTP impairment, is rescued by L-lactate but not equicaloric glucose. Disrupting the expression of the neuronal lactate transporter MCT2 also leads to amnesia that is unaffected by either L-lactate or glucose, suggesting that lactate import into neurons is necessary for long-term memory. Glycogenolysis and astrocytic lactate transporters are also critical for the induction of molecular changes required for memory formation, including the induction of phospho-CREB, Arc, and phospho-cofilin. We conclude that astrocyte-neuron lactate transport is required for long-term memory formation. Copyright © 2011 Elsevier Inc. All rights reserved.

Astrocyte-neuron lactate transport is required for long-term memory formation

PubMed Central

Suzuki, Akinobu; Stern, Sarah A.; Bozdagi, Ozlem; Huntley, George W.; Walker, Ruth H.; Magistretti, Pierre J.; Alberini, Cristina M.

2011-01-01

SUMMARY We report that in the rat hippocampus learning leads to a significant increase in extracellular lactate levels, which derive from glycogen, an energy reserve selectively localized in astrocytes. Astrocytic glycogen breakdown and lactate release are essential for long-term but not short-term memory formation, and for the maintenance of long-term potentiation (LTP) of synaptic strength elicited in-vivo. Disrupting the expression of the astrocytic lactate transporters monocarboxylate transporter 4 (MCT4) or MCT1 causes amnesia, which, like LTP impairment, is rescued by lactate but not equicaloric glucose. Disrupting the expression of the neuronal lactate transporter MCT2 also leads to amnesia that is unaffected by either L-lactate or glucose, suggesting that lactate import into neurons is necessary for long-term memory. Glycogenolysis and astrocytic lactate transporters are also critical for the induction of molecular changes required for memory formation, including the induction of phospho-CREB, Arc and phospho-cofilin. We conclude that astrocyte-neuron lactate transport is required for long-term memory formation. PMID:21376239

Long-term CO2 production following permafrost thawing

Treesearch

B. Elberling; A. Michelsen; C. Schadel; E.A.G. Schuur; H.H. Christiansen; L. Berg; M.P. Tamstorf; C. Sigsgaard

2013-01-01

Thawing permafrost represents a poorly understood feedback mechanism of climate change in the Arctic, but with a potential impact owing to stored carbon being mobilized1–5. We have quantified the long-term loss of carbon (C) from thawing permafrost in Northeast Greenland from 1996 to 2008 by combining repeated sediment sampling to assess changes...

Short-term Action Intentions Overrule Long-Term Semantic Knowledge

ERIC Educational Resources Information Center

van Elk, M.; van Schie, H.T.; Bekkering, H.

2009-01-01

In the present study, we investigated whether the preparation of an unusual action with an object (e.g. bringing a cup towards the eye) could selectively overrule long-term semantic representations. In the first experiment it was found that unusual action intentions activated short-term semantic goal representations, rather than long-term…

Globalization, women's migration, and the long-term-care workforce.

PubMed

Browne, Colette V; Braun, Kathryn L

2008-02-01

With the aging of the world's population comes the rising need for qualified direct long-term-care (DLTC) workers (i.e., those who provide personal care to frail and disabled older adults). Developed nations are increasingly turning to immigrant women to fill these needs. In this article, we examine the impact of three global trends-population aging, globalization, and women's migration-on the supply and demand for DLTC workers in the United States. Following an overview of these trends, we identify three areas with embedded social justice issues that are shaping the DLTC workforce in the United States, with a specific focus on immigrant workers in these settings. These include world poverty and economic inequalities, the feminization and colorization of labor (especially in long-term care), and empowerment and women's rights. We conclude with a discussion of the contradictory effects that both population aging and globalization have on immigrant women, source countries, and the long-term-care workforce in the United States. We raise a number of policy, practice, and research implications and questions. For policy makers and long-term-care administrators in receiver nations such as the United States, the meeting of DLTC worker needs with immigrants may result in greater access to needed employees but also in the continued devaluation of eldercare as a profession. Source (supply) nations must balance the real and potential economic benefits of remittances from women who migrate for labor with the negative consequences of disrupting family care traditions and draining the long-term-care workforce of those countries.

Archiving Primary Data: Solutions for Long-Term Studies.

PubMed

Mills, James A; Teplitsky, Céline; Arroyo, Beatriz; Charmantier, Anne; Becker, Peter H; Birkhead, Tim R; Bize, Pierre; Blumstein, Daniel T; Bonenfant, Christophe; Boutin, Stan; Bushuev, Andrey; Cam, Emmanuelle; Cockburn, Andrew; Côté, Steeve D; Coulson, John C; Daunt, Francis; Dingemanse, Niels J; Doligez, Blandine; Drummond, Hugh; Espie, Richard H M; Festa-Bianchet, Marco; Frentiu, Francesca; Fitzpatrick, John W; Furness, Robert W; Garant, Dany; Gauthier, Gilles; Grant, Peter R; Griesser, Michael; Gustafsson, Lars; Hansson, Bengt; Harris, Michael P; Jiguet, Frédéric; Kjellander, Petter; Korpimäki, Erkki; Krebs, Charles J; Lens, Luc; Linnell, John D C; Low, Matthew; McAdam, Andrew; Margalida, Antoni; Merilä, Juha; Møller, Anders P; Nakagawa, Shinichi; Nilsson, Jan-Åke; Nisbet, Ian C T; van Noordwijk, Arie J; Oro, Daniel; Pärt, Tomas; Pelletier, Fanie; Potti, Jaime; Pujol, Benoit; Réale, Denis; Rockwell, Robert F; Ropert-Coudert, Yan; Roulin, Alexandre; Sedinger, James S; Swenson, Jon E; Thébaud, Christophe; Visser, Marcel E; Wanless, Sarah; Westneat, David F; Wilson, Alastair J; Zedrosser, Andreas

2015-10-01

The recent trend for journals to require open access to primary data included in publications has been embraced by many biologists, but has caused apprehension amongst researchers engaged in long-term ecological and evolutionary studies. A worldwide survey of 73 principal investigators (Pls) with long-term studies revealed positive attitudes towards sharing data with the agreement or involvement of the PI, and 93% of PIs have historically shared data. Only 8% were in favor of uncontrolled, open access to primary data while 63% expressed serious concern. We present here their viewpoint on an issue that can have non-trivial scientific consequences. We discuss potential costs of public data archiving and provide possible solutions to meet the needs of journals and researchers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Noncontact ECG system for unobtrusive long-term monitoring.

PubMed

McDonald, Neil J; Anumula, Harini A; Duff, Eric; Soussou, Walid

2012-01-01

This paper describes measurements made using an ECG system with QUASAR's capacitive bioelectrodes integrated into a pad system that is placed over a chair. QUASAR's capacitive bioelectrode has the property of measuring bioelectric potentials at a small separation from the body. This enables the measurement of ECG signals through fabric, without the removal of clothing or preparation of skin. The ECG was measured through the subject's clothing while the subject sat in the chair without any supporting action from the subject. The ECG pad system is an example of a high compliance system that places minimal requirements upon the subject and, consequently, can be used to generate a long-term record from ECG segments collected on a daily basis, providing valuable information on long-term trends in cardiac health.

Employee experience of workplace supervisor contact and support during long-term sickness absence.

PubMed

Buys, Nicholas J; Selander, John; Sun, Jing

2017-12-07

Workplace support is an important factor in promoting successful return to work. The purpose of this article is to examine relationships between supervisor contact, perceived workplace support and demographic variables among employees on long-term sickness absence. Data were collected from 204 public employees at a municipality in Sweden who had been on long term sickness absence (60 days or more) using a 23 question survey instrument that collected information on demographic variables, supervisor contact and perceived workplace support. Most injured employees (97%) reported having contact with their supervisors during their sickness absence, with a majority (56%) reporting high levels of support, including early (58.6%) and multiple (70.7%) contacts. Most were pleased with amount of contact (68.9%) and the majority had discussed workplace accommodations (68.1%). Employees who self-initiated contact, felt the amount of contact was appropriate, had a personal meeting with their supervisors and discussed workplace adjustments reported experiencing higher levels of support from supervisors. Employees on long-term sickness absence appreciate contact from their supervisors and this is associated with perceived workplace support. However, the amount and employee experience of this contact is important. It needs to be perceived by employees as supportive, which includes a focus on strategies (e.g., work adjustment) to facilitate a return to work. Supervisor training is required in this area to support the return to work process. Implications for Rehabilitation Contact and support from workplace supervisors is important to workers on long-term sickness absence. Employees appreciate frequent contact from supervisors during long-terms sickness absence. Employees appreciate a personal meeting with supervisors and the opportunity to discuss issues related to return to work such as work adjustment. Employers should provide training to supervisors on how to communicate and

Representational Specificity of Within-Category Phonetic Variation in the Long-Term Mental Lexicon

ERIC Educational Resources Information Center

Ju, Min; Luce, Paul A.

2006-01-01

This study examines the potential encoding in long-term memory of subphonemic, within-category variation in voice onset time (VOT) and the degree to which this encoding of subtle variation is mediated by lexical competition. In 4 long-term repetition-priming experiments, magnitude of priming was examined as a function of variation in VOT in words…

Despair-associated memory requires a slow-onset CA1 long-term potentiation with unique underlying mechanisms

PubMed Central

Jing, Liang; Duan, Ting-Ting; Tian, Meng; Yuan, Qiang; Tan, Ji-Wei; Zhu, Yong-Yong; Ding, Ze-Yang; Cao, Jun; Yang, Yue-Xiong; Zhang, Xia; Mao, Rong-Rong; Richter-levin, Gal; Zhou, Qi-Xin; Xu, Lin

2015-01-01

The emotion of despair that occurs with uncontrollable stressful event is probably retained by memory, termed despair-associated memory, although little is known about the underlying mechanisms. Here, we report that forced swimming (FS) with no hope to escape, but not hopefully escapable swimming (ES), enhances hippocampal α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)-dependent GluA1 Ser831 phosphorylation (S831-P), induces a slow-onset CA1 long-term potentiation (LTP) in freely moving rats and leads to increased test immobility 24-h later. Before FS application of the antagonists to block S831-P or N-methyl-D-aspartic acid receptor (NMDAR) or glucocorticoid receptor (GR) disrupts LTP and reduces test immobility, to levels similar to those of the ES group. Because these mechanisms are specifically linked with the hopeless of escape from FS, we suggest that despair-associated memory occurs with an endogenous CA1 LTP that is intriguingly mediated by a unique combination of rapid S831-P with NMDAR and GR activation to shape subsequent behavioral despair. PMID:26449319

Long-term effects of cannabis on oculomotor function in humans.

PubMed

Huestegge, L; Radach, R; Kunert, H J

2009-08-01

Cannabis is known to affect human cognitive and visuomotor skills directly after consumption. Some studies even point to rather long-lasting effects, especially after chronic tetrahydrocannabinol (THC) abuse. However, it is still unknown whether long-term effects on basic visual and oculomotor processing may exist. In the present study, the performance of 20 healthy long-term cannabis users without acute THC intoxication and 20 control subjects were examined in four basic visuomotor paradigms to search for specific long-term impairments. Subjects were asked to perform: 1) reflexive saccades to visual targets (prosaccades), including gap and overlap conditions, 2) voluntary antisaccades, 3) memory-guided saccades and 4) double-step saccades. Spatial and temporal parameters of the saccades were subsequently analysed. THC subjects exhibited a significant increase of latency in the prosaccade and antisaccade tasks, as well as prolonged saccade amplitudes in the antisaccade and memory-guided task, compared with the control subjects. The results point to substantial and specific long-term deficits in basic temporal processing of saccades and impaired visuo-spatial working memory. We suggest that these impairments are a major contributor to degraded performance of chronic users in a vital everyday task like visual search, and they might potentially also affect spatial navigation and reading.

Birds choose long-term partners years before breeding

USGS Publications Warehouse

Teitelbaum, Claire S.; Converse, Sarah J.; Mueller, Thomas

2017-01-01

Pair bonds can provide social benefits to long-term monogamous species alongside their benefits for reproduction. However, little is known about when these bonds form, in particular how long they are present before breeding. Previous studies of pair formation in long-term monogamous birds have been rather data-limited, but for many migratory birds they report pair formation on the wintering grounds. We provide the first systematic investigation of prebreeding association patterns of long-term monogamous pairs by examining entire life histories based on tracking data of migratory whooping cranes, Grus americana. We found that a substantial portion (62%) of breeding pairs started associating at least 12 months before first breeding, with 16 of 58 breeding pairs beginning to associate over 2 years before first breeding. For most pairs, these associations with future breeding partners also became unique and distinguishable from association patterns with nonpartner individuals 12 months before first breeding. In addition, 60% of pair associations began before at least one partner had reached nominal sexual maturity. Most pairs began associating in the late spring upon arrival at the summer grounds, while associations beginning at other times of the year were rare. Patterns in the associations of pairs prior to breeding can point to the potential benefits of prebreeding relationships, for instance providing support in competitive interactions or increasing partner familiarity.

Peripheral arteriovenous fistula as vascular access for long-term chemotherapy.

PubMed

Kovalyov, Oleksiy O; Kostyuk, Oleksandr G; Tkachuk, Tetyana V

To provide long-term vascular access in clinical oncology peripheral forearm veins (up to 95% of patients in Ukraine), central venous access and "complete implanted vascular systems" are used most often. Many oncology patients have contraindications to catheterization of superior vena cava. Besides, exploitation of central veins is associated with potential technical and infectious complications. The aim - to study short-term and long-term results of arteriovenous fistula exploitation as vascular access for continuous anticancer therapy. Peripheral venous bed status in 41 oncology patients taking long-term chemotherapy treatment is analyzed in the article. Doppler sonography, morphologic and immune histochemical analyses were used in the study. Doppler sonography found qualitative and quantitative changes in forearm veins at different time periods after initiation of chemotherapy in the majority of patients. The major morphologic manifestations of venous wall damage were chemical phlebitis, local or extended hardening of venous wall, venous thrombosis and extravasations with necrosis and subsequent paravasal tissue sclerosis. Alternative vascular access created in 12 patients completely met the adequacy criteria (safety, multiple use, longevity, realization of the designed therapy program). The conclusion was made about inapplicability of forearm veins for long-term administration of cytostatic agents. If it is impossible to use central veins, arteriovenous fistula can become an alternative vascular access.

Adenosine 2A Receptor Inhibition Enhances Intermittent Hypoxia-Induced Diaphragm but Not Intercostal Long-Term Facilitation

PubMed Central

Navarrete-Opazo, Angela A.; Vinit, Stéphane

2014-01-01

Abstract Acute intermittent hypoxia (AIH) elicits diaphragm (Dia) and second external intercostal (T2 EIC) long-term facilitation (LTF) in normal unanesthetized rats. Although AIH-induced phrenic LTF is serotonin dependent, adenosine constrained in anesthetized rats, this has not been tested in unanesthetized animals. Cervical (C2) spinal hemisection (C2HS) abolishes phrenic LTF because of loss of serotonergic inputs 2 weeks post-injury, but LTF returns 8 weeks post-injury. We tested three hypotheses in unanesthetized rats: (1) systemic adenosine 2aA (A2A) receptor inhibition with intraperitoneal (IP) KW6002 enhances Dia and T2 EIC LTF in normal rats; (2) Dia and T2 EIC LTF are expressed after chronic (8 weeks), but not acute (1 week) C2HS; and (3) KW6002 enhances Dia and T2 EIC LTF after chronic (not acute) C2HS. Electromyography radiotelemetry was used to record Dia and T2 EIC activity during normoxia (21% O2), before and after AIH (10, 5-min 10.5% O2, 5-min intervals). In normal rats, KW6002 enhanced DiaLTF versus AIH alone (33.1±4.6% vs. 22.1±6.4% baseline, respectively; p<0.001), but had no effect on T2 EIC LTF (p>0.05). Although Dia and T2 EIC LTF were not observed 2 weeks post-C2HS, LTF was observed in contralateral (uninjured) Dia and T2 EIC 8 weeks post-C2HS (18.7±2.7% and 34.9±4.9% baseline, respectively; p<0.05), with variable ipsilateral expression. KW6002 had no significant effects on contralateral Dia (p=0.447) or T2 EIC LTF (p=0.796). We conclude that moderate AIH induces Dia and T2 EIC LTF after chronic, but not acute cervical spinal injuries. A single A2A receptor antagonist dose enhances AIH-induced Dia LTF in normal rats, but this effect is not significant in chronic (8 weeks) C2HS unanesthetized rats. PMID:25003645

Estimating long-term multivariate progression from short-term data.

PubMed

Donohue, Michael C; Jacqmin-Gadda, Hélène; Le Goff, Mélanie; Thomas, Ronald G; Raman, Rema; Gamst, Anthony C; Beckett, Laurel A; Jack, Clifford R; Weiner, Michael W; Dartigues, Jean-François; Aisen, Paul S

2014-10-01

Diseases that progress slowly are often studied by observing cohorts at different stages of disease for short periods of time. The Alzheimer's Disease Neuroimaging Initiative (ADNI) follows elders with various degrees of cognitive impairment, from normal to impaired. The study includes a rich panel of novel cognitive tests, biomarkers, and brain images collected every 6 months for as long as 6 years. The relative timing of the observations with respect to disease pathology is unknown. We propose a general semiparametric model and iterative estimation procedure to estimate simultaneously the pathological timing and long-term growth curves. The resulting estimates of long-term progression are fine-tuned using cognitive trajectories derived from the long-term "Personnes Agées Quid" study. We demonstrate with simulations that the method can recover long-term disease trends from short-term observations. The method also estimates temporal ordering of individuals with respect to disease pathology, providing subject-specific prognostic estimates of the time until onset of symptoms. When the method is applied to ADNI data, the estimated growth curves are in general agreement with prevailing theories of the Alzheimer's disease cascade. Other data sets with common outcome measures can be combined using the proposed algorithm. Software to fit the model and reproduce results with the statistical software R is available as the grace package. ADNI data can be downloaded from the Laboratory of NeuroImaging. Copyright © 2014 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Hydrotherapy for the long-term ventilated patient: A case study and implications for practice.

PubMed

Wegner, Sally; Thomas, Peter; James, Christine

2017-11-01

Hydrotherapy of mechanically ventilated patients has been shown to be safe and feasible in both the acute stages of critical illness and in those requiring long term mechanical ventilation. This case study describes the hydrotherapy sessions of a 36 year old female, who after suffering complications of pneumococcal meningitis, became an incomplete quadriplegic and required long term mechanical ventilation. When implementing hydrotherapy with patients on mechanical ventilation a number of factors should be considered. These include staff resources and training, airway and ventilation management, patient preparation and safety procedures. Hydrotherapy can be safely utilised with mechanically ventilated patients, and may facilitate a patient's ability to participate in active exercise and rehabilitation. Copyright © 2017 Australian College of Critical Care Nurses Ltd. All rights reserved.

Long term potentiation depends on release of D-serine from astrocytes

PubMed Central

Henneberger, Christian; Papouin, Thomas; Oliet, Stéphane H. R.; Rusakov, Dmitri A.

2009-01-01

Long-term potentiation (LTP) of synaptic transmission provides an experimental model for studying mechanisms of memory1. The classical form of LTP relies on N-methyl-D-aspartate receptors (NMDARs), and it has emerged that astroglia can regulate their activation through Ca2+-dependent release of the NMDAR co-agonist D-serine2-4. Release of D-serine from glia enables LTP in cultures5 and explains a correlation between glial coverage of synapses and LTP in the supraoptic nucleus4. However, Ca2+ elevations in astroglia can also release other signalling molecules, most prominently glutamate6-8, Adenosine-5′-triphosphate9, and Tumor-Necrosis-Factor-α10,11 whereas neurons themselves can synthesise and supply D-serine12,13. Furthermore, loading an astrocyte with exogenous Ca2+ buffers does not suppress LTP in hippocampal area CA114-16, and the physiological relevance of experiments in cultures or strong exogenous stimuli applied to astrocytes has been questioned17,18. The involvement of glia in LTP induction thus remains controversial. Here we show that clamping internal Ca2+ in individual CA1 astrocytes blocks LTP induction at nearby excitatory synapses by reducing the occupancy of the NMDAR co-agonist sites. This LTP blockade can be reversed by exogenous D-serine or glycine whereas depletion of D-serine or disruption of exocytosis in an individual astrocyte blocks local LTP. We thus demonstrate that Ca2+-dependent release of D-serine from an astrocyte controls NMDAR-dependent plasticity in many thousands of excitatory synapses occurring nearby. PMID:20075918

Long-term deconditioning of gas-filled surge arresters

NASA Astrophysics Data System (ADS)

Stanković, Koviljka; Brajović, Dragan; Alimpijević, Mališa; Lončar, Boris

2016-07-01

pressure that is as high as possible (with pd = const), and that the electrode active surface should have a marked microscopic topography. In addition to this, an essential conclusion for GFSA manufacturers is that long-term system deconditioning is caused by impurities and adsorbed gases that appear at electrode during the state of rest. Out of these two causes, the influence of impurities is probably the dominant one, which is proved by considerably reduced long-term deconditioning in the case of noble metal electrodes, not susceptible to corrosion. This has also been confirmed by a less distinct effect of long-term deconditioning in the case of sandblasted electrodes that have a stronger tendency towards gas adsorption and a weaker tendency towards corrosion. However, it has been shown that adding of the third electrode (that is concentric to the main electrode system) on a free floating potential along with usage of sandblasted electrodes and with smaller interelectrode distance significantly reduces the effects of the long-term deconditioning.

Long-term memory of heterospecific vocalizations by African lions

NASA Astrophysics Data System (ADS)

Grinnell, Jon; van Dyk, Gus; Slotow, Rob

2005-09-01

Animals that use and evaluate long-distance signals have the potential to glean valuable information about others in their environment via eavesdropping. In those areas where they coexist, African lions (Panthera leo) are a significant eavesdropper on spotted hyenas (Crocuta crocuta), often using hyena vocalizations to locate and scavenge from hyena kills. This relationship was used to test African lions' long-term memory of the vocalizations of spotted hyenas via playback experiments. Hyena whoops and a control sound (Canis lupus howls) were played to three populations of lions in South Africa: (1) lions with past experience of spotted hyenas; (2) lions with current experience; and (3) lions with no experience. The results strongly suggest that lions have the cognitive ability to remember the vocalizations of spotted hyenas even after 10 years with no contact of any kind with them. Such long-term memory of heterospecific vocalizations may be widespread in species that gain fitness benefits from eavesdropping on others, but where such species are sympatric and often interact it may pass unrecognized as short-term memory instead.

Experience with long-term glucocorticoid treatment in congenital adrenal hyperplasia: growth pattern compared with genetic height potential.

PubMed

Aycan, Zehra; Ocal, Gonul; Berberoglu, Merih; Cetinkaya, Ergun; Adiyaman, Pelin; Evliyaoglu, Olcay

2006-03-01

Long-term replacement treatment with high doses of steroids in congenital adrenal hyperplasia (CAH) is known to have a negative influence on growth. We evaluated the effects of long-term steroid treatment in patients with classical CAH on height development in relation to genetic height potential. Twenty-three patients with CAH (16 females, 7 males, mean age: 9.8 +/- 3.5 years) were included in this longitudinal study. The effect of steroid treatment on growth was determined by monitoring patients for 8.61 +/- 3.46 years (2-17 years) while they were treated with hydrocortisone at a mean dosage of 17.64 +/- 3.60 mg/m2/day. The height standard deviation scores (Ht-SDS), target Ht-SDS, and corrected Ht-SDS for target height was calculated for all patients. Predicted adult height according to bone age was calculated and it was determined whether height was developing according to the genetic height potential. In addition, patients were grouped as 'tight control' or 'poor control' according to their mean serum 17OH-progesterone or ACTH levels while on treatment. We evaluated whether height development was different for the tight and poor control groups. The mean chronological age of our patients at the time of the study was 9.89 +/- 3.53 years, Ht-SDS -0.77 +/- 1.57, target height (TH) 161.03 +/- 6.54 cm, TH-SDS -0.60 +/- 0.90, predicted height (PH) 157.2 +/- 11.16 cm, PH-SDS -1.1 +/- 1.69, and corrected Ht-SDS -0.75 +/- 1.14. There was no significant difference between the actual Ht-SDS and TH-SDS of our patients (p >0.05) but the corrected Ht-SDS was less than zero. Only 28.5% of our patients had normal height according to their genetic potential while 71.5% were shorter than their genetic height potential. While the Ht-SDS and corrected Ht-SDS were similar in the tight and poor metabolic control groups, the predicted height was significantly greater in the tight control group. We demonstrated that a hydrocortisone dose of 17.64 +/- 3.60 mg/m2/day in classical CAH had

Fluoxetine Inhibits Natural Decay of Long-Term Memory via Akt/GSK-3β Signaling.

PubMed

Yi, Jee Hyun; Zhang, JiaBao; Ko, Sang Yoon; Kwon, Huiyoung; Jeon, Se Jin; Park, Se Jin; Jung, Jiwook; Kim, Byung C; Lee, Young Choon; Kim, Dong Hyun; Ryu, Jong Hoon

2018-02-09

Understanding the mechanisms underlying the natural decay of long-term memory can help us find means of extending the duration of long-term memory. However, the neurobiological processes involved in the decay of long-term memory are poorly understood. In the present study, we examined the effect of acute and chronic treatment of fluoxetine on natural decay of long-term memory and the possible mechanism. Late administration of fluoxetine prolonged the persistence of long-term memory in mice, as demonstrated by object location recognition and Barnes maze tests. Fluoxetine altered Akt/glycogen synthase kinase-3β (GSK-3β)/β-catenin signaling in the hippocampus. Late short- and long-term pharmacological inhibition of GSK-3β mimicked the effect of fluoxetine on memory persistence. Pharmacological inhibition of Akt blocked the effect of fluoxetine on memory persistence. Finally, late infusion of fluoxetine increased hippocampal long-term potentiation (LTP) and pharmacological inhibition of GSK-3β blocked the natural decline in LTP. These results demonstrate that GSK-3β might be a key molecule in memory decay process, and fluoxetine extends the period of long-term memory maintenance via Akt/GSK-3β signaling.

An European framework for the long term preservation of EO data

NASA Astrophysics Data System (ADS)

Forcada, E.; Albani, M.; Beruti, V.

2009-04-01

(including Canada) EO data for an unlimited time-span ensuring and facilitating their accessibility and usability through the implementation of a cooperative and harmonized collective approach among the EO data owners. Such European Long Term Data Preservation Framework should be implemented through the application of European LTDP Common Guidelines and sustained through cooperative (multi-source) long term funding schemes. The Long Term Data Preservation Working Group with representatives from ASI, CNES, CSA, DLR and ESA was formed at the end of 2007 within the Ground Segment Coordination Body (GSCB, http://earth.esa.int/gscb/) with the goal to define and promote, with the involvement of all the European EO data and archive owners, the LTDP Common Guidelines. During the 1st Earth Observation Long Term Data Preservation workshop in May 2008, the guidelines and the framework were presented and debated by all European and Canadian EO data owners, data providers and archive holders. The participants discussed and developed a joint strategy to move ahead technically and programmatically concerning the Long Term Data Preservation of EO Data and recognized the need and benefits of a common approach. Furthermore all the participants identified and agreed the LTDP Guidelines presented at the workshop as a first concrete and fundamental step to move ahead in creating the Long Term Data Preservation Framework. ESA is already planning to apply the Long Term Data Preservation Common Guidelines to its own missions and the consolidated LTDP guidelines will be promoted within CEOS and GEO.

Long-term low-dose α-particle enhanced the potential of malignant transformation in human bronchial epithelial cells through MAPK/Akt pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Weili; Xiao, Linlin; Dong, Chen

2014-05-09

Highlights: • Multi-exposures of 25 mGy α-ray enhanced cell proliferation, adhesion, and invasion. • MAPK/Akt but not JNK/P66 was positively correlated with cell invasive phenotypes. • LDR of α-irradiation triggers cell malignant transformation through MAPK/Akt. - Abstract: Since the wide usage of ionizing radiation, the cancer risk of low dose radiation (LDR) (<0.1 Gy) has become attractive for a long time. However, most results are derived from epidemiologic studies on atomic-bomb survivors and nuclear accidents surrounding population, and the molecular mechanism of this risk is elusive. To explore the potential of a long-term LDR-induced malignant transformation, human bronchial epithelial cellsmore » Beas-2B were fractionally irradiated with 0.025 Gy α-particles for 8 times in total and then further cultured for 1–2 months. It was found that the cell proliferation, the abilities of adhesion and invasion, and the protein expressions of p-ERK, p-Akt, especially p-P38 were not only increased in the multiply-irradiated cells but also in their offspring 1–2 months after the final exposure, indicating high potentiality of cell malignant transformation. On opposite, the expressions of p-JNK and p-P66 were diminished in the subcultures of irradiated cells and thus may play a role of negative regulation in canceration. When the cells were transferred with p38 siRNA, the LDR-induced enhancements of cell adhesion and invasion were significantly reduced. These findings suggest that long-term LDR of α-particles could enhance the potential of malignant transformation incidence in human bronchial epithelial cells through MAPK/Akt pathway.« less

Organomatics and organometrics: Novel platforms for long-term whole-organ culture

PubMed Central

Bruinsma, Bote G.; Yarmush, Martin L.; Uygun, Korkut

2014-01-01

Organ culture systems are instrumental as experimental whole-organ models of physiology and disease, as well as preservation modalities facilitating organ replacement therapies such as transplantation. Nevertheless, a coordinated system of machine perfusion components and integrated regulatory control has yet to be fully developed to achieve long-term maintenance of organ function ex vivo. Here we outline current strategies for organ culture, or organomatics, and how these systems can be regulated by means of computational algorithms, or organometrics, to achieve the organ culture platforms anticipated in modern-day biomedicine. PMID:25035864

Impact of long-term wetting on belowground respiration and methanogenesis in Luther Bog, Ontario

NASA Astrophysics Data System (ADS)

Goebel, Marie; Blodau, Christian

2016-04-01

Peatlands play a major role in the global carbon cycle. They store one-third of total world soil carbon, sequester carbon dioxide (CO2) and release CO2 and methane (CH4). Climate and land-use change are predicted to cause either wetter winters and wetter summers or wetter winters and drier summers in the area where northern peatlands are located. Feedback on processes in the peat is poorly understood on the time scale of decades. In this study, we investigated impacts of long-term wetting and long-term fluctuating water table on potential CO2 and CH4 production rates and organic matter quality of the fractions bulk peat, pore water and leachate. Bulk peat potential CO2 production rates of 2.38 to 25.55 μmol g-1 d-1 (aerobic) and 1.53 to 7.33 μmol g-1 d-1 (anaerobic) decreased with depth along with a decrease in organic matter quality. Potential CH4 production rates (0.002 to 2.60 μmol g-1 d-1) increased with anaerobic conditions and a lack of electron acceptors rather than being dependent on the availability of labile organic matter. This pattern was less evident in solute fraction samples where labile compounds in top layers were probably either too labile to be detected or water movement obscured differences between depths. Bulk peat potential anaerobic CO2 and CH4 production increased through long-term wetting. As wetting did not change organic matter quality or aerobic production rates, increased anaerobic production rates likely originate from microorganisms adapted to anaerobic conditions. All indicators of organic matter quality, FTIR ratios, SUVA254, E2:E3, HIX, FI and PARAFAC, provided similar results. Other than expected, wetting did not result in higher organic matter quality in bulk peat and leachate. Drier conditions in summer led to reduced organic matter quality. In pore water, long-term wetter conditions resulted in a higher organic matter quality. Slow-down of decomposition due to anaerobic conditions is unlikely, as this was not the case with

Space Life Sciences Research: The Importance of Long-Term Space Experiments

NASA Technical Reports Server (NTRS)

1993-01-01

This report focuses on the scientific importance of long-term space experiments for the advancement of biological science and the benefit of humankind. It includes a collection of papers that explore the scientific potential provided by the capability to manipulate organisms by removing a force that has been instrumental in the evolution and development of all organisms. Further, it provides the scientific justification for why the long-term space exposure that can be provided by a space station is essential to conduct significant research.

Daily Acclimation Handling Does Not Affect Hippocampal Long-Term Potentiation or Cause Chronic Sleep Deprivation in Mice

PubMed Central

Vecsey, Christopher G.; Wimmer, Mathieu E. J.; Havekes, Robbert; Park, Alan J.; Perron, Isaac J.; Meerlo, Peter; Abel, Ted

2013-01-01

Study Objectives: Gentle handling is commonly used to perform brief sleep deprivation in rodents. It was recently reported that daily acclimation handling, which is often used before behavioral assays, causes alterations in sleep, stress, and levels of N-methyl-D-aspartate receptor subunits prior to the actual period of sleep deprivation. It was therefore suggested that acclimation handling could mediate some of the observed effects of subsequent sleep deprivation. Here, we examine whether acclimation handling, performed as in our sleep deprivation studies, alters sleep/wake behavior, stress, or forms of hippocampal synaptic plasticity that are impaired by sleep deprivation. Design: Adult C57BL/6J mice were either handled daily for 6 days or were left undisturbed in their home cages. On the day after the 6th day of handling, long-term potentiation (LTP) was induced in hippocampal slices with spaced four-train stimulation, which we previously demonstrated to be impaired by brief sleep deprivation. Basal synaptic properties were also assessed. In three other sets of animals, activity monitoring, polysomnography, and stress hormone measurements were performed during the 6 days of handling. Results: Daily gentle handling alone does not alter LTP, rest/activity patterns, or sleep/wake architecture. Handling initially induces a minimal stress response, but by the 6th day, stress hormone levels are unaltered by handling. Conclusion: It is possible to handle mice daily to accustom them to the researcher without causing alterations in sleep, stress, or synaptic plasticity in the hippocampus. Therefore, effects of acclimation handling cannot explain the impairments in signaling mechanisms, synaptic plasticity, and memory that result from brief sleep deprivation. Citation: Vecsey CG; Wimmer MEJ; Havekes R; Park AJ; Perron IJ; Meerlo P; Abel T. Daily acclimation handling does not affect hippocampal long-term potentiation or cause chronic sleep deprivation in mice. SLEEP 2013

Synaptic scaling enables dynamically distinct short- and long-term memory formation.

PubMed

Tetzlaff, Christian; Kolodziejski, Christoph; Timme, Marc; Tsodyks, Misha; Wörgötter, Florentin

2013-10-01

Memory storage in the brain relies on mechanisms acting on time scales from minutes, for long-term synaptic potentiation, to days, for memory consolidation. During such processes, neural circuits distinguish synapses relevant for forming a long-term storage, which are consolidated, from synapses of short-term storage, which fade. How time scale integration and synaptic differentiation is simultaneously achieved remains unclear. Here we show that synaptic scaling - a slow process usually associated with the maintenance of activity homeostasis - combined with synaptic plasticity may simultaneously achieve both, thereby providing a natural separation of short- from long-term storage. The interaction between plasticity and scaling provides also an explanation for an established paradox where memory consolidation critically depends on the exact order of learning and recall. These results indicate that scaling may be fundamental for stabilizing memories, providing a dynamic link between early and late memory formation processes.

Synaptic Scaling Enables Dynamically Distinct Short- and Long-Term Memory Formation

PubMed Central

Tetzlaff, Christian; Kolodziejski, Christoph; Timme, Marc; Tsodyks, Misha; Wörgötter, Florentin

2013-01-01

Memory storage in the brain relies on mechanisms acting on time scales from minutes, for long-term synaptic potentiation, to days, for memory consolidation. During such processes, neural circuits distinguish synapses relevant for forming a long-term storage, which are consolidated, from synapses of short-term storage, which fade. How time scale integration and synaptic differentiation is simultaneously achieved remains unclear. Here we show that synaptic scaling – a slow process usually associated with the maintenance of activity homeostasis – combined with synaptic plasticity may simultaneously achieve both, thereby providing a natural separation of short- from long-term storage. The interaction between plasticity and scaling provides also an explanation for an established paradox where memory consolidation critically depends on the exact order of learning and recall. These results indicate that scaling may be fundamental for stabilizing memories, providing a dynamic link between early and late memory formation processes. PMID:24204240

Very long-term sequelae of craniopharyngioma.

PubMed

Wijnen, Mark; van den Heuvel-Eibrink, Marry M; Janssen, Joseph A M J L; Catsman-Berrevoets, Coriene E; Michiels, Erna M C; van Veelen-Vincent, Marie-Lise C; Dallenga, Alof H G; van den Berge, J Herbert; van Rij, Carolien M; van der Lely, Aart-Jan; Neggers, Sebastian J C M M

2017-06-01

Studies investigating long-term health conditions in patients with craniopharyngioma are limited by short follow-up durations and generally do not compare long-term health effects according to initial craniopharyngioma treatment approach. In addition, studies comparing long-term health conditions between patients with childhood- and adult-onset craniopharyngioma report conflicting results. The objective of this study was to analyse a full spectrum of long-term health effects in patients with craniopharyngioma according to initial treatment approach and age group at craniopharyngioma presentation. Cross-sectional study based on retrospective data. We studied a single-centre cohort of 128 patients with craniopharyngioma treated from 1980 onwards (63 patients with childhood-onset disease). Median follow-up since craniopharyngioma presentation was 13 years (interquartile range: 5-23 years). Initial craniopharyngioma treatment approaches included gross total resection ( n  = 25), subtotal resection without radiotherapy ( n  = 44), subtotal resection with radiotherapy ( n  = 25), cyst aspiration without radiotherapy ( n  = 8), and 90 Yttrium brachytherapy ( n  = 21). Pituitary hormone deficiencies (98%), visual disturbances (75%) and obesity (56%) were the most common long-term health conditions observed. Different initial craniopharyngioma treatment approaches resulted in similar long-term health effects. Patients with childhood-onset craniopharyngioma experienced significantly more growth hormone deficiency, diabetes insipidus, panhypopituitarism, morbid obesity, epilepsy and psychiatric conditions compared with patients with adult-onset disease. Recurrence-/progression-free survival was significantly lower after initial craniopharyngioma treatment with cyst aspiration compared with other therapeutic approaches. Survival was similar between patients with childhood- and adult-onset craniopharyngioma. Long-term health conditions were comparable after

Attenuation of hippocampal mossy fiber long-term potentiation by low micromolar concentrations of zinc.

PubMed

Takeda, Atsushi; Kanno, Shingo; Sakurada, Naomi; Ando, Masaki; Oku, Naoto

2008-10-01

The role of zinc in long-term potentiation (LTP) at hippocampal mossy fiber synapses is controversial because of the contrary results obtained when using zinc chelators. On the basis of the postulation that exogenous zinc enhances the action of zinc released from mossy fibers, mossy fiber LTP after tetanic stimulation (100 Hz, 1 sec) was checked in the presence of exogenous zinc at low micromolar concentrations. Mossy fiber LTP was significantly attenuated in the presence of 5-30 microM ZnCl(2), and the amplitude of field excitatory postsynaptic potentials 60 min after tetanic stimulation was decreased to almost the basal level. Mossy fiber LTP was also attenuated in the presence of 5 microM ZnCl(2) 5 min after tetanic stimulation. The present study is the first to demonstrate that low micromolar concentrations of zinc attenuate mossy fiber LTP. When mossy fiber LTP was induced in the presence of CaEDTA and ZnAF-2 DA, a membrane-impermeable and a membrane-permeable zinc chelator, respectively, extracellular and intracellular chelation of zinc enhanced a transient posttetanic potentiation (PTP) without altering LTP. It is likely that zinc released by tetanic stimulation is immediately taken up into the mossy fibers and attenuates mossy fiber PTP. These results suggest that attenuation of PTP rather than LTP at mossy fiber synapses is a more physiological role for endogenous zinc. Targeting molecules of zinc in mossy fiber LTP seem to be different between during and after LTP induction because of the differential synaptic activity between them. (c) 2008 Wiley-Liss, Inc.

A Model for the Development of Virtual Communities for People with Long-Term, Severe Physical Disabilities

ERIC Educational Resources Information Center

Tilley, C. M.; Bruce, C. S.; Hallam, G.; Hills, A. P.

2006-01-01

Introduction: This paper reports results of an investigation into the needs of persons with disabilities wanting to participate in the use of virtual communities. The aim was to investigate "how virtual communities for persons with long-term, severe physical disabilities can best be facilitated"? Method: A Grounded Theory approach was…

Long-term no-till and stover retention each decrease the global warming potential of irrigated continuous corn.

PubMed

Jin, Virginia L; Schmer, Marty R; Stewart, Catherine E; Sindelar, Aaron J; Varvel, Gary E; Wienhold, Brian J

2017-07-01

Over the last 50 years, the most increase in cultivated land area globally has been due to a doubling of irrigated land. Long-term agronomic management impacts on soil organic carbon (SOC) stocks, soil greenhouse gas (GHG) emissions, and global warming potential (GWP) in irrigated systems, however, remain relatively unknown. Here, residue and tillage management effects were quantified by measuring soil nitrous oxide (N 2 O) and methane (CH 4 ) fluxes and SOC changes (ΔSOC) at a long-term, irrigated continuous corn (Zea mays L.) system in eastern Nebraska, United States. Management treatments began in 2002, and measured treatments included no or high stover removal (0 or 6.8 Mg DM ha -1  yr -1 , respectively) under no-till (NT) or conventional disk tillage (CT) with full irrigation (n = 4). Soil N 2 O and CH 4 fluxes were measured for five crop-years (2011-2015), and ΔSOC was determined on an equivalent mass basis to ~30 cm soil depth. Both area- and yield-scaled soil N 2 O emissions were greater with stover retention compared to removal and for CT compared to NT, with no interaction between stover and tillage practices. Methane comprised <1% of total emissions, with NT being CH 4 neutral and CT a CH 4 source. Surface SOC decreased with stover removal and with CT after 14 years of management. When ΔSOC, soil GHG emissions, and agronomic energy usage were used to calculate system GWP, all management systems were net GHG sources. Conservation practices (NT, stover retention) each decreased system GWP compared to conventional practices (CT, stover removal), but pairing conservation practices conferred no additional mitigation benefit. Although cropping system, management equipment/timing/history, soil type, location, weather, and the depth to which ΔSOC is measured affect the GWP outcomes of irrigated systems at large, this long-term irrigated study provides valuable empirical evidence of how management decisions can impact soil GHG emissions and surface

Long-term care in international perspective.

PubMed

Doty, P

1988-12-01

The findings of a study of long-term care policies in 18 countries are reported in this article. Initial data were collected by a questionnaire survey under the auspices of the International Social Security Association. These data were supplemented by published documents and government statistics obtained while researching long-term care for the International Social Security Association and, subsequently, for the Organization for Economic Cooperation and Development. The principal focus is a cross-national comparison of institutionalization rates for the elderly. Differences in use rates for medically oriented facilities are less than those for nonmedical residential long-term care facilities. Only a small amount of variation is related to demographic differences, such as older or more female elderly populations in those countries with higher institutionalization rates. Included also is a description of the modes of financing long-term care.

Long-term potentiation protects rat hippocampal slices from the effects of acute hypoxia.

PubMed

Youssef, F F; Addae, J I; McRae, A; Stone, T W

2001-07-13

We have previously shown that long-term potentiation (LTP) decreases the sensitivity of glutamate receptors in the rat hippocampal CA1 region to exogenously applied glutamate agonists. Since the pathophysiology of hypoxia/ischemia involves increased concentration of endogenous glutamate, we tested the hypothesis that LTP could reduce the effects of hypoxia in the hippocampal slice. The effects of LTP on hypoxia were measured by the changes in population spike potentials (PS) or field excitatory post-synaptic potentials (fepsps). Hypoxia was induced by perfusing the slice with (i) artificial CSF which had been pre-gassed with 95%N2/5% CO2; (ii) artificial CSF which had not been pre-gassed with 95% O2/5% CO2; or (iii) an oxygen-glucose deprived (OGD) medium which was similar to (ii) and in which the glucose had been replaced with sucrose. Exposure of a slice to a hypoxic medium for 1.5-3.0 min led to a decrease in the PS or fepsps; the potentials recovered to control levels within 3-5 min. Repeat exposure, 45 min later, of the same slice to the same hypoxic medium for the same duration as the first exposure caused a reduction in the potentials again; there were no significant differences between the degree of reduction caused by the first or second exposure for all three types of hypoxic media (P>0.05; paired t-test). In some of the slices, two episodes of LTP were induced 25 and 35 min after the first hypoxic exposure; this caused inhibition of reduction in potentials caused by the second hypoxic insult which was given at 45 min after the first; the differences in reduction in potentials were highly significant for all the hypoxic media used (P<0.01; paired t-test). The neuroprotective effects of LTP were not prevented by cyclothiazide or inhibitors of NO synthetase compounds that have been shown to be effective in blocking the effects of LTP on the actions of exogenously applied AMPA and NMDA, respectively. The neuroprotective effects of LTP were similar to those

Channel gating kinetics and synaptic efficacy: a hypothesis for expression of long-term potentiation.

PubMed Central

Ambros-Ingerson, J; Lynch, G

1993-01-01

A kinetic model of the glutamate DL-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor/channel complex was used to test whether changes in the rate constants describing channel behavior could account for various features of long-term potentiation (LTP). Starting values for the kinetic parameters were set to satisfy experimental data (e.g., affinity, mean open time, mean burst length, etc.) and physical constraints (i.e., microreversibility). The resultant model exhibited a variety of dynamic properties known to be associated with the receptor. Increasing the rate constants governing opening/closing of the channel produced an unexpected increase in the probability of the channel being open shortly after transmitter binding. This would account for the enhanced response size with LTP. Increases in rate constants produced two other aspects of LTP: (i) an alteration of the waveform of the synaptic response and (ii) an interaction with changes in desensitization kinetics. The results obtained with the model corresponded closely to those found in LTP experiments. Thus, an increase in opening/closing rates for the postsynaptic receptor channel provides a single explanation for diverse characteristics of LTP. Finally, the kinetic manipulation reduced the coefficient of variation of synaptic currents in a model involving 250 receptors. This calls into question the use of variance measures for distinguishing pre- vs. postsynaptic sites of potentiation. PMID:8395058

Long-term athletic development- part 1: a pathway for all youth.

PubMed

Lloyd, Rhodri S; Oliver, Jon L; Faigenbaum, Avery D; Howard, Rick; De Ste Croix, Mark B A; Williams, Craig A; Best, Thomas M; Alvar, Brent A; Micheli, Lyle J; Thomas, D Phillip; Hatfield, Disa L; Cronin, John B; Myer, Gregory D

2015-05-01

The concept of developing talent and athleticism in youth is the goal of many coaches and sports systems. Consequently, an increasing number of sporting organizations have adopted long-term athletic development models in an attempt to provide a structured approach to the training of youth. It is clear that maximizing sporting talent is an important goal of long-term athletic development models. However, ensuring that youth of all ages and abilities are provided with a strategic plan for the development of their health and physical fitness is also important to maximize physical activity participation rates, reduce the risk of sport- and activity-related injury, and to ensure long-term health and well-being. Critical reviews of independent models of long-term athletic development are already present within the literature; however, to the best of our knowledge, a comprehensive examination and review of the most prominent models does not exist. Additionally, considerations of modern day issues that may impact on the success of any long-term athletic development model are lacking, as are proposed solutions to address such issues. Therefore, within this 2-part commentary, Part 1 provides a critical review of existing models of practice for long-term athletic development and introduces a composite youth development model that includes the integration of talent, psychosocial and physical development across maturation. Part 2 identifies limiting factors that may restrict the success of such models and offers potential solutions.

Representativeness of shorter measurement sessions in long-term indoor air monitoring.

PubMed

Maciejewska, M; Szczurek, A

2015-02-01

Indoor air quality (IAQ) considerably influences health, comfort and the overall performance of people who spend most of their lives in confined spaces. For this reason, there is a strong need to develop methods for IAQ assessment. The fundamental issue in the quantitative determination of IAQ is the duration of measurements. Its inadequate choice may result in providing incorrect information and this potentially leads to wrong conclusions. The most complete information may be acquired through long-term monitoring. However it is typically perceived as impractical due to time and cost load. The aim of this study was to determine whether long-term monitoring can be adequately represented by a shorter measurement session. There were considered three measurable quantities: temperature, relative humidity and carbon dioxide concentration. They are commonly recognized as indicatives for IAQ and may be readily monitored. Scaled Kullback-Leibler divergence, also called relative entropy, was applied as a measure of data representativeness. We considered long-term monitoring in a range from 1 to 9 months. Based on our work, the representative data on CO2 concentration may be acquired while performing measurements during 20% of time dedicated to long-term monitoring. In the case of temperature and relative humidity the respective time demand was 50% of long-term monitoring. From our results, in indoor air monitoring strategies, there could be considered shorter measurement sessions, while still collecting data which are representative for long-term monitoring.

Competitive short-term and long-term memory processes in spatial habituation.

PubMed

Sanderson, David J; Bannerman, David M

2011-04-01

Exposure to a spatial location leads to habituation of exploration such that, in a novelty preference test, rodents subsequently prefer exploring a novel location to the familiar location. According to Wagner's (1981) theory of memory, short-term and long-term habituation are caused by separate and sometimes opponent processes. In the present study, this dual-process account of memory was tested. Mice received a series of exposure training trials to a location before receiving a novelty preference test. The novelty preference was greater when tested after a short, rather than a long, interval. In contrast, the novelty preference was weaker when exposure training trials were separated by a short, rather than a long interval. Furthermore, it was found that long-term habituation was determined by the independent effects of the amount of exposure training and the number of exposure training trials when factors such as the intertrial interval and the cumulative intertrial interval were controlled. A final experiment demonstrated that a long-term reduction of exploration could be caused by a negative priming effect due to associations formed during exploration. These results provide evidence against a single-process account of habituation and suggest that spatial habituation is determined by both short-term, recency-based memory and long-term, incrementally strengthened memory.

Effects of ethanolic extract and naphthoquinones obtained from the bulbs of Cipura paludosa on short-term and long-term memory: involvement of adenosine A₁ and A₂A receptors.

PubMed

Lucena, Greice M R S; Matheus, Filipe C; Ferreira, Vania M; Tessele, Priscila B; Azevedo, Mariangela S; Cechinel-Filho, Valdir; Prediger, Rui D

2013-04-01

Previous studies from our group have indicated important biological properties of the ethanolic extract and isolated compounds from the bulbs of Cipura paludosa (Iridaceae), a native plant widely distributed in northern Brazil, including antioxidant, neuroprotective and anti-nociceptive activities. In the present study, the effects of the ethanolic extract and its two naphthoquinones (eleutherine and isoeleutherine) on the short- and long-term memory of adult rodents were assessed in social recognition and inhibitory avoidance tasks. Acute pre-training oral administration of the ethanolic extract improved the short-term social memory in rats as well as facilitated the step-down inhibitory avoidance short- and long-term memory in mice. Moreover, the co-administration of 'non-effective' doses of the extract of Cipura paludosa and the adenosine receptor antagonists caffeine (non-selective), DPCPX (adenosine A1 receptor antagonist) and ZM241385 (adenosine A2A receptor antagonist) improved the social recognition memory of rats. In the inhibitory avoidance task, the co-administration of sub-effective doses of the extract with caffeine or ZM241385, but not with DPCPX, improved the short- and long-term memory of mice. Finally, the acute oral administration of eleutherine and isoeleutherine facilitated the inhibitory avoidance short- and long-term memory in mice. These results demonstrate for the first time the cognitive-enhancing properties of the extract and isolated compounds from the bulbs of Cipura paludosa in rodents and suggest a possible involvement of adenosine A1 and A2A receptors in these effects. © 2012 The Authors Basic & Clinical Pharmacology & Toxicology © 2012 Nordic Pharmacological Society.

Coordination of short-term and long-term mitigation measures of hydro-meteorological risks: the importance of establishing a link between emergency management and spatial planning

NASA Astrophysics Data System (ADS)

Prenger-Berninghoff, Kathrin; Cortes, V. Juliette; Aye, Zar Chi; Sprague, Teresa

2013-04-01

by means of exploratory questionnaires and interviews with government agencies, local administrations, community and research organizations on each study site. First results provided will address the general role of spatial planning in risk management. Additionally, preliminary observations are made in regard to the coordination of emergency preparedness and long-term spatial planning activities. The observations consider that integration facilitates proactive strategies that aim at preventing disaster occurrence and promote interaction between involved parties. Finally, consideration is given to the potential use of a DSS tool to cover both aspects of spatial planning and emergency management in the risk management cycle.

Effects of Long-term Diving Training on Cortical Gyrification.

PubMed

Zhang, Yuanchao; Zhao, Lu; Bi, Wenwei; Wang, Yue; Wei, Gaoxia; Evans, Alan; Jiang, Tianzi

2016-06-20

During human brain development, cortical gyrification, which is believed to facilitate compact wiring of neural circuits, has been shown to follow an inverted U-shaped curve, coinciding with the two-stage neurodevelopmental process of initial synaptic overproduction with subsequent pruning. This trajectory allows postnatal experiences to refine the wiring, which may manifest as endophenotypic changes in cortical gyrification. Diving experts, typical elite athletes who commence intensive motor training at a very young age in their early childhood, serve ideal models for examining the gyrification changes related to long-term intensive diving training. Using local gyrification index (LGI), we compared the cortical gyrification between 12 diving experts and 12 controls. Compared with controls, diving experts showed widespread LGI reductions in regions relevant to diving performance. Negative correlations between LGIs and years of diving training were also observed in diving experts. Further exploratory network efficiency analysis of structural cortical networks, inferred from interregional correlation of LGIs, revealed comparable global and local efficiency in diving experts relative to controls. These findings suggest that gyrification reductions in diving experts may be the result of long-term diving training which could refine the neural circuitry (via synaptic pruning) and might be the anatomical substrate underlying their extraordinary diving performance.

Long-term potentiation in spinal nociceptive pathways as a novel target for pain therapy

PubMed Central

2011-01-01

Long-term potentiation (LTP) in nociceptive spinal pathways shares several features with hyperalgesia and has been proposed to be a cellular mechanism of pain amplification in acute and chronic pain states. Spinal LTP is typically induced by noxious input and has therefore been hypothesized to contribute to acute postoperative pain and to forms of chronic pain that develop from an initial painful event, peripheral inflammation or neuropathy. Under this assumption, preventing LTP induction may help to prevent the development of exaggerated postoperative pain and reversing established LTP may help to treat patients who have an LTP component to their chronic pain. Spinal LTP is also induced by abrupt opioid withdrawal, making it a possible mechanism of some forms of opioid-induced hyperalgesia. Here, we give an overview of targets for preventing LTP induction and modifying established LTP as identified in animal studies. We discuss which of the various symptoms of human experimental and clinical pain may be manifestations of spinal LTP, review the pharmacology of these possible human LTP manifestations and compare it to the pharmacology of spinal LTP in rodents. PMID:21443797

Business Students' Choice of Short-Term or Long-Term Study Abroad Opportunities

ERIC Educational Resources Information Center

Fitzsimmons, Stacey R.; Flanagan, David J.; Wang, Xiaodan

2013-01-01

Recent years have seen a proliferation of short-term study abroad opportunities. Although they are both supplementing and replacing semester-long study abroad programs, research has focused primarily on semester (long-term) programs. We draw on the theory of planned behavior (TPB) to explore factors that predict why students choose long-term and…

A Dynamic Anesthesia System for Long-Term Imaging in Adult Zebrafish

PubMed Central

Wynd, Brenen M.; Watson, Claire J.; Patil, Karuna; Sanders, George E.

2017-01-01

Abstract Long-term in vivo imaging in adult zebrafish (i.e., 1–24 h) has been limited by the fact that regimens for long-term anesthesia in embryos and larvae are ineffective in adults. Here, we examined the potential for dynamic administration of benzocaine to enable long-term anesthesia in adult zebrafish. We developed a computer-controlled perfusion system comprised of programmable peristaltic pumps that enabled automatic exchange between anesthetic and system water. Continuous administration of benzocaine in adult zebrafish resulted in a mean time to respiratory arrest of 5.0 h and 8-h survival of 14.3%. We measured characteristic sedation and recovery times in response to benzocaine, and used them to devise an intermittent dosing regimen consisting of 14.5 min of benzocaine followed by 5.5 min of system water. Intermittent benzocaine administration in adult zebrafish resulted in a mean time to respiratory arrest of 7.6 h and 8-h survival of 71.4%. Finally, we performed a single 24-h trial and found that intermittent dosing maintained anesthesia in an adult zebrafish over the entire 24-h period. In summary, our studies demonstrate the potential for dynamic administration of benzocaine to enable prolonged anesthesia in adult zebrafish, expanding the potential for imaging in adult physiologies that unfold over 1–24 h. PMID:27409411

A Dynamic Anesthesia System for Long-Term Imaging in Adult Zebrafish.

PubMed

Wynd, Brenen M; Watson, Claire J; Patil, Karuna; Sanders, George E; Kwon, Ronald Y

2017-02-01

Long-term in vivo imaging in adult zebrafish (i.e., 1-24 h) has been limited by the fact that regimens for long-term anesthesia in embryos and larvae are ineffective in adults. Here, we examined the potential for dynamic administration of benzocaine to enable long-term anesthesia in adult zebrafish. We developed a computer-controlled perfusion system comprised of programmable peristaltic pumps that enabled automatic exchange between anesthetic and system water. Continuous administration of benzocaine in adult zebrafish resulted in a mean time to respiratory arrest of 5.0 h and 8-h survival of 14.3%. We measured characteristic sedation and recovery times in response to benzocaine, and used them to devise an intermittent dosing regimen consisting of 14.5 min of benzocaine followed by 5.5 min of system water. Intermittent benzocaine administration in adult zebrafish resulted in a mean time to respiratory arrest of 7.6 h and 8-h survival of 71.4%. Finally, we performed a single 24-h trial and found that intermittent dosing maintained anesthesia in an adult zebrafish over the entire 24-h period. In summary, our studies demonstrate the potential for dynamic administration of benzocaine to enable prolonged anesthesia in adult zebrafish, expanding the potential for imaging in adult physiologies that unfold over 1-24 h.

Immediate and Long-Term Impacts of Child Sexual Abuse.

ERIC Educational Resources Information Center

Briere, John N.; Elliott, Diana M.

1994-01-01

Summarizes what is currently known about the potential, immediate, and long-term impact of child sexual abuse. The various problems and symptoms described in the literature on child sexual abuse are reviewed in a series of broad categories including posttraumatic stress, cognitive distortions, emotional pain, avoidance, an impaired sense of self,…

Long-term forest management and climate effects on streamflow

Treesearch

Shelby G. Laird; C.R. Ford; S.H. Laseter; J.M. Vose

2011-01-01

Long-term watershed studies are a powerful tool for examining interactions among management activities, streamflow, and climatic variability. Understanding these interactions is critical for exploring the potential of forest management to adapt to or mitigate against the effects of climate change. The Coweeta Hydrologic Laboratory, located in North Carolina, USA, is a...

Protein Kinase M[Zeta] Is Essential for the Induction and Maintenance of Dopamine-Induced Long-Term Potentiation in Apical CA1 Dendrites

ERIC Educational Resources Information Center

Navakkode, Sheeja; Sajikumar, Sreedharan; Sacktor, Todd Charlton; Frey, Julietta U.

2010-01-01

Dopaminergic D1/D5-receptor-mediated processes are important for certain forms of memory as well as for a cellular model of memory, hippocampal long-term potentiation (LTP) in the CA1 region of the hippocampus. D1/D5-receptor function is required for the induction of the protein synthesis-dependent maintenance of CA1-LTP (L-LTP) through activation…

Effects of Joint Attention on Long-Term Memory in 9-Month-Old Infants: An Event-Related Potentials Study

ERIC Educational Resources Information Center

Kopp, Franziska; Lindenberger, Ulman

2011-01-01

Joint attention develops during the first year of life but little is known about its effects on long-term memory. We investigated whether joint attention modulates long-term memory in 9-month-old infants. Infants were familiarized with visually presented objects in either of two conditions that differed in the degree of joint attention (high…

Hypomagnesaemia associated with long-term use of proton pump inhibitors

PubMed Central

Toh, James Wei Tatt; Ong, Evonne; Wilson, Robert

2015-01-01

Hypomagnesaemia and associated hypocalcaemia and hypoparathyroidism have been increasingly recognised as rare long-term side-effects of proton pump inhibitors (PPIs). The PPIs may inhibit active magnesium (Mg) absorption by interfering with transcellular transient receptor potential melastatin-6 and -7 (TRPM 6 and 7) channels. More recent cell culture studies have suggested concomitant inhibition of passive Mg absorption by omeprazole. After being treated with a range of PPIs, the four patients in our case series developed hypomagnesaemia, which responded to withdrawal of therapy and initiation of Mg replacement. Their clinical course and management demonstrate key aspects of hypomagnesaemia associated with long-term use of PPIs. PMID:25138239

Long-term bed degradation in Maryland streams (phase 3, part I) : urban streams in the Piedmont Plateau province.

DOT National Transportation Integrated Search

2014-05-01

Estimation of potential long-term down-cutting of the stream bed is necessary for evaluation and design of bridges for scour and culverts for fish passage. The purpose of this study has been to improve predictions of this potential long-term bed degr...

Self-reported immature defense style as a predictor of outcome in short-term and long-term psychotherapy.

PubMed

Laaksonen, Maarit A; Sirkiä, Carlos; Knekt, Paul; Lindfors, Olavi

2014-07-01

Identification of pretreatment patient characteristics predictive of psychotherapy outcome could help to guide treatment choices. This study evaluates patients' initial level of immature defense style as a predictor of the outcome of short-term versus long-term psychotherapy. In the Helsinki Psychotherapy Study, 326 adult outpatients with mood or anxiety disorder were randomized to individual short-term (psychodynamic or solution-focused) or long-term (psychodynamic) psychotherapy. Their defense style was assessed at baseline using the 88-item Defense Style Questionnaire and classified as low or high around the median value of the respective score. Both specific (Beck Depression Inventory [BDI], Hamilton Depression Rating Scale [HDRS], Symptom Check List Anxiety Scale [SCL-90-Anx], Hamilton Anxiety Rating Scale [HARS]) and global (Symptom Check List Global Severity Index [SCL-90-GSI], Global Assessment of Functioning Scale [GAF]) psychiatric symptoms were measured at baseline and 3-7 times during a 3-year follow-up. Patients with high use of immature defense style experienced greater symptom reduction in long-term than in short-term psychotherapy by the end of the 3-year follow-up (50% vs. 34%). Patients with low use of immature defense style experienced faster symptom reduction in short-term than in long-term psychotherapy during the first year of follow-up (34% vs. 19%). Knowledge of patients' initial level of immature defense style may potentially be utilized in tailoring treatments. Further research on defense styles as outcome predictors in psychotherapies of different types is needed.

The long-term effects of birthing interventions on childhood empathy.

PubMed

Cassels, Tracy G

2014-04-01

birthing practices have changed drastically over the past century. It is now more common for women to birth in a hospital, receive drug interventions, and to birth via caesarean section, yet there is a paucity of research on long-term outcomes associated with practices. The research was designed to determine if there were any long-term effects of the birthing experience on child empathic behaviour. two-hundred-and-sixty-four mother-child dyad (M(child_age)=5.92 years; SD=.85 years; 127 boys) completed either a questionnaire on birthing practices (mothers) or a modified Stickers Task to assess empathic behaviour (child). there was a non-significant effect (Δ=.22, p=.395) of home versus hospital birth and a small-moderate, significant (Δ=.33, p=.017) effect of the use of epidurals during, with children of mothers who did not use an epidural or who birthed at home showing greater empathic behaviour. the birthing location and the decision to have an epidural can have long-term consequences on children's empathy. While researchers need to further examine the mechanisms behind these findings, parents should be made aware of the potential long-term effects in order to allow them to make fully informed decisions. Copyright © 2013 Elsevier Ltd. All rights reserved.

Long Periodic Terms in the Solar System

NASA Technical Reports Server (NTRS)

Bretagnon, P.

1982-01-01

The long period variations of the first eight planets in the solar system are studied. First, the Lagrangian solution is calculated and then the long period terms with fourth order eccentricities and inclinations are introduced into the perturbation function. A second approximation was made taking into account the short period terms' contribution, namely the perturbations of first order with respect to the masses. Special attention was paid to the determination of the integration constants. The relative importance of the different contributions is shown. It is useless, for example, to introduce the long period terms of fifth order if no account has been taken of the short period terms. Meanwhile, the terms that have been neglected would not introduce large changes in the integration constants. Even so, the calculation should be repeated with higher order short period terms and fifth order long periods.

Long-Term Hearing Results After Ossiculoplasty.

PubMed

Cox, Matthew D; Trinidade, Aaron; Russell, James Shep; Dornhoffer, John L

2017-04-01

To determine if the OOPS index is predictive of long-term hearing results after ossiculoplasty. Case series with retrospective chart review. Tertiary care otology practice. Adult and pediatric patients (3-88 years of age). Ossiculoplasty with cartilage tympanoplasty, with or without mastoidectomy. Primary outcome measures included short-term hearing results (pure-tone average air-bone gap [PTA-ABG] measured between 60 days and 1 year after surgery), long-term hearing results (PTA-ABG measured ≥5 years after surgery), and the rate of successful ABG closure to ≤20 dB. Secondary measures included the need for revision surgery, delayed tympanic membrane graft failure, worsening conductive hearing loss (after an initially satisfactory hearing result), and recurrence of cholesteatoma. There was no significant difference between adults and children for short-term hearing results (average post-op PTA-ABG was 18.9 dB vs. 19.8 dB, respectively; p = 0.544), long-term hearing results (average final PTA-ABG was 19.3 dB vs. 19.4 dB, respectively; p = 0.922), or rate of ABG closure to less than 20 dB (63.1% vs. 58.0%, p = 0.282). Spearman's rank-order correlation (ρ) identified a strong positive correlation between OOPS index score and average post-operative PTA-ABG (ρ = 0.983; p < 0.001; 2-tailed), as well as average long-term PTA-ABG (ρ = 0.950, p < 0.001; 2-tailed). The OOPS index makes it possible to accurately prognosticate hearing outcomes in adult and pediatric patients undergoing ossiculoplasty in both the short term and the long term.

Short-term memory and long-term memory are still different.

PubMed

Norris, Dennis

2017-09-01

A commonly expressed view is that short-term memory (STM) is nothing more than activated long-term memory. If true, this would overturn a central tenet of cognitive psychology-the idea that there are functionally and neurobiologically distinct short- and long-term stores. Here I present an updated case for a separation between short- and long-term stores, focusing on the computational demands placed on any STM system. STM must support memory for previously unencountered information, the storage of multiple tokens of the same type, and variable binding. None of these can be achieved simply by activating long-term memory. For example, even a simple sequence of digits such as "1, 3, 1" where there are 2 tokens of the digit "1" cannot be stored in the correct order simply by activating the representations of the digits "1" and "3" in LTM. I also review recent neuroimaging data that has been presented as evidence that STM is activated LTM and show that these data are exactly what one would expect to see based on a conventional 2-store view. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Short-Term Memory and Long-Term Memory are Still Different

PubMed Central

2017-01-01

A commonly expressed view is that short-term memory (STM) is nothing more than activated long-term memory. If true, this would overturn a central tenet of cognitive psychology—the idea that there are functionally and neurobiologically distinct short- and long-term stores. Here I present an updated case for a separation between short- and long-term stores, focusing on the computational demands placed on any STM system. STM must support memory for previously unencountered information, the storage of multiple tokens of the same type, and variable binding. None of these can be achieved simply by activating long-term memory. For example, even a simple sequence of digits such as “1, 3, 1” where there are 2 tokens of the digit “1” cannot be stored in the correct order simply by activating the representations of the digits “1” and “3” in LTM. I also review recent neuroimaging data that has been presented as evidence that STM is activated LTM and show that these data are exactly what one would expect to see based on a conventional 2-store view. PMID:28530428

Aging of Dissolved Copper and Copper-based Nanoparticles in Five Different Soils: Short-term Kinetics vs. Long-term Fate

EPA Science Inventory

With the growing availability and use of copper-based nanomaterials (Cu-NMs), there is increasing concern regarding their release and potential impact on the environment. In this study, the short term (≤5 d) aging profile and the long-term (135 d) speciation of dissolved Cu, cop...

Long-Term Soil Chemistry Changes in Aggrading Forest Ecosystems

Treesearch

Jennifer D. Knoepp; Wayne T. Swank

1994-01-01

Assessing potential long-term forest productivity requires identification of the processes regulating chemical changes in forest soils. We resampled the litter layer and upper two mineral soil horizons, A and AB/BA, in two aggrading southern Appalachian watersheds 20 yr after an earlier sampling. Soils from a mixed-hardwood watershed exhibited a small but significant...

Endogenous 17β-estradiol is required for activity-dependent long-term potentiation in the striatum: interaction with the dopaminergic system

PubMed Central

Tozzi, Alessandro; de Iure, Antonio; Tantucci, Michela; Durante, Valentina; Quiroga-Varela, Ana; Giampà, Carmela; Di Mauro, Michela; Mazzocchetti, Petra; Costa, Cinzia; Di Filippo, Massimiliano; Grassi, Silvarosa; Pettorossi, Vito Enrico; Calabresi, Paolo

2015-01-01

17β-estradiol (E2), a neurosteroid synthesized by P450-aromatase (ARO), modulates various brain functions. We characterized the role of the locally synthesized E2 on striatal long-term synaptic plasticity and explored possible interactions between E2 receptors (ERs) and dopamine (DA) receptors in the dorsal striatum of adult male rats. Inhibition of E2 synthesis or antagonism of ERs prevented the induction of long-term potentiation (LTP) in both medium spiny neurons (MSNs) and cholinergic interneurons (ChIs). Activation of a D1-like DA receptor/cAMP/PKA-dependent pathway restored LTP. In MSNs exogenous E2 reversed the effect of ARO inhibition. Also antagonism of M1 muscarinic receptors prevented the D1-like receptor-mediated restoration of LTP confirming a role for ChIs in controlling the E2-mediated LTP of MSNs. A novel striatal interaction, occurring between ERs and D1-like receptors in both MSNs and ChIs, might be critical to regulate basal ganglia physiology and to compensate synaptic alterations in Parkinson’s disease. PMID:26074768

Endogenous 17β-estradiol is required for activity-dependent long-term potentiation in the striatum: interaction with the dopaminergic system.

PubMed

Tozzi, Alessandro; de Iure, Antonio; Tantucci, Michela; Durante, Valentina; Quiroga-Varela, Ana; Giampà, Carmela; Di Mauro, Michela; Mazzocchetti, Petra; Costa, Cinzia; Di Filippo, Massimiliano; Grassi, Silvarosa; Pettorossi, Vito Enrico; Calabresi, Paolo

2015-01-01

17β-estradiol (E2), a neurosteroid synthesized by P450-aromatase (ARO), modulates various brain functions. We characterized the role of the locally synthesized E2 on striatal long-term synaptic plasticity and explored possible interactions between E2 receptors (ERs) and dopamine (DA) receptors in the dorsal striatum of adult male rats. Inhibition of E2 synthesis or antagonism of ERs prevented the induction of long-term potentiation (LTP) in both medium spiny neurons (MSNs) and cholinergic interneurons (ChIs). Activation of a D1-like DA receptor/cAMP/PKA-dependent pathway restored LTP. In MSNs exogenous E2 reversed the effect of ARO inhibition. Also antagonism of M1 muscarinic receptors prevented the D1-like receptor-mediated restoration of LTP confirming a role for ChIs in controlling the E2-mediated LTP of MSNs. A novel striatal interaction, occurring between ERs and D1-like receptors in both MSNs and ChIs, might be critical to regulate basal ganglia physiology and to compensate synaptic alterations in Parkinson's disease.

Men's Sheds: enabling environments for Australian men living with and without long-term disabilities.

PubMed

Hansji, Neeraj L; Wilson, Nathan J; Cordier, Reinie

2015-05-01

The health of Australian men has recently received greater attention. Men's Sheds are named in national policy as an exemplar community-based organisation for the betterment of men's psychosocial health; yet, the evidence base to support this is limited. This study investigates the comparative experience of men with long-term disabilities and men without long-term disabilities who go to a Men's Shed and to what extent this provides these men with an enabling, as opposed to disabling, environment. Data were collected from 12 individual interviews with men with long-term disabilities (5) and men without long-term disabilities (6), including 1 interview with the male Men's Shed Coordinator (MSC); participant observation within the shed; and a document received from the female MSC regarding the funding the Shed receives. Interviews explored the men's experiences at the Shed and their sense of belonging and social inclusion. Participants had any type of long-term disability and had been attending the shed for a minimum of 1 month. Data were collected between May and September 2013 and were analysed using the constant comparative method of grounded theory. The core theme that emerged was an enabling community space. The four sub-themes were: a community and social hub; an equalising space; a safe and supportive male environment; and meaningful male activities. The current literature exemplifies Men's Sheds to be important community-based organisations beneficial to men's health and well-being. For men living with long-term disabilities, this study illuminates that Men's Sheds offer an environment of equality, facilitating a collegial and egalitarian culture. Men can partake in enabling activities and enjoy the company of other men enhancing their sense of belonging and social inclusion as well as interact with other community groups that occupy the same space as the Men's Shed. © 2014 John Wiley & Sons Ltd.

Long-term preservation of Leptospira spp.: challenges and prospects.

PubMed

Philip, Noraini; Garba, Bashiru; Neela, Vasantha Kumari

2018-05-08

Preservation of leptospiral cultures is tantamount to success in leptospiral diagnostics, research, and development of preventive strategies. Each Leptospira isolate has imperative value not only in disease diagnosis but also in epidemiology, virulence, pathogenesis, and drug development studies. As the number of circulating leptospires is continuously increasing and congruent with the importance to retain their original characteristics and properties, an efficient long-term preservation is critically needed to be well-established. However, the preservation of Leptospira is currently characterized by difficulties and conflicting results mainly due to the biological nature of this organism. Hence, this review seeks to describe the efforts in developing efficient preservation methods, to discover the challenges in preserving this organism and to identify the factors that can contribute to an effective long-term preservation of Leptospira. Through the enlightenment of the previous studies, a potentially effective method has been suggested. The article also attempts to evaluate novel strategies used in other industrial and biotechnological preservation efforts and consider their potential application to the conservation of Leptospira spp.

Long-Term Stability of Oxide Nanowire Sensors via Heavily Doped Oxide Contact.

PubMed

Zeng, Hao; Takahashi, Tsunaki; Kanai, Masaki; Zhang, Guozhu; He, Yong; Nagashima, Kazuki; Yanagida, Takeshi

2017-12-22

Long-term stability of a chemical sensor is an essential quality for long-term collection of data related to exhaled breath, environmental air, and other sources in the Internet of things (IoT) era. Although an oxide nanowire sensor has shown great potential as a chemical sensor, the long-term stability of sensitivity has not been realized yet due to electrical degradation under harsh sensing conditions. Here, we report a rational concept to accomplish long-term electrical stability of metal oxide nanowire sensors via introduction of a heavily doped metal oxide contact layer. Antimony-doped SnO 2 (ATO) contacts on SnO 2 nanowires show much more stable and lower electrical contact resistance than conventional Ti contacts for high temperature (200 °C) conditions, which are required to operate chemical sensors. The stable and low contact resistance of ATO was confirmed for at least 1960 h under 200 °C in open air. This heavily doped oxide contact enables us to realize the long-term stability of SnO 2 nanowire sensors while maintaining the sensitivity for both NO 2 gas and light (photo) detections. The applicability of our method is confirmed for sensors on a flexible polyethylene naphthalate (PEN) substrate. Since the proposed fundamental concept can be applied to various oxide nanostructures, it will give a foundation for designing long-term stable oxide nanomaterial-based IoT sensors.

Long-term prospects for developments in space: A scenario approach

NASA Technical Reports Server (NTRS)

Brown, W. M.; Kahn, H. D.

1977-01-01

Long-term plans for future NASA programs are reported, and some of the following topics are discussed in detail: (1) systematic formulation of space scenarios; (2) the basic international context; (3) potential 21st century space developments; (4) space vehicle developments; and (5) future exploration.

Long term management practices influenced soil aggregation and carbon dynamics

USDA-ARS?s Scientific Manuscript database

Soil aggregation protects soil organic C (SOC) against rapid decomposition, improves soil quality, and reduces soil erosion potential. The objectives of this study are to evaluate the effects of long-term (21 yrs.) management practices on SOC, water stable aggregate (WSA), and aggregate-associated ...

Short-term exposure to JP-8 jet fuel results in long-term immunotoxicity.

PubMed

Harris, D T; Sakiestewa, D; Robledo, R F; Witten, M

1997-01-01

Chronic exposure to jet fuel has been shown to have adverse effects on human liver function, to cause emotional dysfunction, to cause abnormal electroencephalograms, to cause shortened attention spans, and to decrease sensorimotor speed. Due to the decision by the United States Air Force to implement the widespread use of JP-8 jet fuel in its operations, a thorough understanding of its potential effects upon exposed personnel is both critical and necessary. Exposure to potential environmental toxicants such as JP-8 may have significant effects on host systems beyond those readily visible (i.e., physiology, cardiology, respiratory, etc.); e.g., the immune system. Previous studies have shown that short-term, low concentration JP-8 exposure had significant effects on the immune system, which should have serious consequences for the exposed host in terms of susceptibility to infectious agents. If these alterations in immune function were long-lasting, it might also result in an increased likelihood of development and/or progression of cancer, as well as autoimmune disease. In the current study, mice were exposed for 1 h/day for 7 days to a moderate (1000 mg/m3) and a high (2500 mg/m3) concentration of aerosolized JP-8 jet fuel to stimulate occupational exposures. One to 28 days after the last exposure the mice were analyzed for effects of the exposure on their immune systems. It was observed that decrease in viable immune cell numbers and immune organ weights found at 24 h after exposure persisted for extended periods of time. Further, JP-8 exposure resulted in significantly decreased immune infection, as analyzed by mitogenesis assays, which persisted for up to 4 weeks post-exposure. Thus, short-term exposure of mice to JP-8 jet fuel caused significant toxicological effects on the immune system, which were long-lasting and persistent. It appears that the immune system may be the most sensitive indicator of toxicological damage due to JP-8 exposure. Such long-term

[Potential analysis for research on Advanced Practice Nursing (APN) for persons with dementia living in long-term care facilities].

PubMed

Koch, Sabine; Fleischer, Steffen

2014-01-01

The nursing Minimum Data Set 3.0 (MDS 3.0) and other nursing quality indices summarise relevant health and nursing outcomes for long-term care that are recommended as quality measures. These are measures like "Percent of High-Risk Residents with Pressure Ulcers", "Percent of Low-Risk Residents Who Lose Control of Their Bowels or Bladder", "Percent of Residents Experiencing One or More Falls with Major Injury", "Percent of Residents Who Lose Too Much Weight" etc. Analyses of healthcare data in Germany showed a substantial higher risk for negative outcomes in the long-term care setting in persons with dementia compared to persons without dementia. There already exist evidence-based guidelines and recommendations for most of the quality measures and underlying health problems (e.g., the German "Expertenstandards in der Pflege"). Implementation and translation of evidence have not been systematically researched yet, and there is uncertainty about structures and processes that support implementation and eventually lead to improved nursing outcomes in people with dementia in long-term care. Studies showed a potential benefit of master-level geriatric advanced practice nurses (GAPNs) concerning the implementation of evidence-based guidelines. This corresponds to the expectation that academic nursing staff positively influences research utilisation in practice. A systematic review identified four controlled trials that evaluated the effectiveness of GAPN on select quality measures. Both the internal and external validity of the trials require a thorough investigation into the intervention before translation and effectiveness research in Germany can be recommended. In accordance with national and international recommendations on the development and clinical evaluation of complex interventions, we recommend a multistage model. Such a model comprises the conceptualisation and adaptation of the original intervention. In this way, the original concept of a GAPN has to be

The long-term use of benzodiazepines: patients' views, accounts and experiences.

PubMed

Barter, G; Cormack, M

1996-12-01

Although a decrease in new prescribing has occurred for anxiolytic benzodiazepines, concerns have been raised that a 'core' of long-term users has been left behind. Typically, elderly people represent this 'core', using the benzodiazepines as hypnotics. The present study focuses on the reasons why hypnotic benzodiazepines are used for protracted lengths of time. By examining patient experiences and cognitions, a deeper understanding may be gained of why patients continue to use benzodiazepines. Elderly, long-term users of benzodiazepine hypnotics were interviewed using a semi-structured interview procedure. A comparison group of non-users of the drugs were given a brief interview to collect comparative data. Interview data were analysed from transcripts using qualitative methodology; statistical comparisons between the groups were made using non-parametric statistics. The long-term users had significantly fewer hours of sleep per night than the non-users. There was some evidence of tolerance and a suggestion that symptoms of withdrawal were maintaining continual use. None of the long-term users had clean knowledge of what their doctors thought of their use of benzodiazepines. The data suggest that the power of the doctor may not be utilized to its full potential in the prevention of long-term use, that at least 50% of elderly benzodiazepine users would like to discontinue use, and that patients need information and advice on how to discontinue these drugs.

Discovering long-term potentiation (LTP) - recollections and reflections on what came after.

PubMed

Lømo, T

2018-02-01

Chance events led me to a lifelong career in scientific research. They paved the way for being the first to see long-term potentiation of synaptic efficiency (LTP) in Per Andersen's laboratory in Oslo in 1966. Here I describe my way to this discovery and the experiments with Tim Bliss in 1968-1969 that led to Bliss and Lømo, 1973. Surprisingly, we later failed to reproduce these results. I discuss possible reasons for this failure, which made us both leave LTP research, in my case for good, in Tim's case for several years. After 30 years of work in a different field, I renewed my interest in the hippocampus and LTP in the early 2000s and published, for the first time, results that I had obtained 40 years earlier. Here I present my take on how interest in and research on LTP evolved after the early years. This includes a discussion of the functions of hippocampus as seen in those early days, the case of patient H.M., Donald Hebb's place in the story, the search for 'memory molecules' such as PKMζ, and the primary site for LTP expression (pre- and/or post-synaptic?). Throughout, I reflect on my life in science, how science is done and what drives it. The reflections are quite personal and I admit to mixed feelings about broadcasting them. © 2017 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

Effect of chronic stress on short and long-term plasticity in dentate gyrus; study of recovery and adaptation.

PubMed

Radahmadi, M; Hosseini, N; Nasimi, A

2014-11-07

Stress dramatically affects synaptic plasticity of the hippocampus, disrupts paired-pulse facilitation and impairs long-term potentiation (LTP). This study was performed to find the effects of chronic restraint stress and recovery period on excitability, paired-pulse response, LTP and to find probable adaptation to very long stress in the dentate gyrus. Thirty-eight male Wistar rats were randomly divided into four groups of Control, Rest-Stress (21 days stress), Stress-Rest (recovery) and Stress-Stress (42 days stress: adaptation). Chronic restraint stress was applied 6-h/day. Input-output functions, paired-pulse responses and LTP were recorded from the dentate gyrus while stimulating the perforant pathway. We found that chronic stress attenuated the responsiveness, paired-pulse response and LTP in the dentate gyrus. A 21-day recovery period, after the stress, improved all the three responses toward normal, indicating reversibility of these stress-related hippocampal changes. There was no significant adaptation to very long stress, probably due to severity of stress. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Prevalence of Long-Term Opioid Use in Long-Stay Nursing Home Residents.

PubMed

Hunnicutt, Jacob N; Chrysanthopoulou, Stavroula A; Ulbricht, Christine M; Hume, Anne L; Tjia, Jennifer; Lapane, Kate L

2018-01-01

Overall and long-term opioid use among older adults have increased since 1999. Less is known about opioid use in older adults in nursing homes (NHs). Cross-sectional. U.S. NHs (N = 13,522). Long-stay NH resident Medicare beneficiaries with a Minimum Data Set 3.0 (MDS) assessment between April 1, 2012, and June 30, 2012, and 120 days of follow-up (N = 315,949). We used Medicare Part D claims to measure length of opioid use in the 120 days from the index assessment (short-term: ≤30 days, medium-term: >30-89 days, long-term: ≥90 days), adjuvants (e.g., anticonvulsants), and other pain medications (e.g., corticosteroids). MDS assessments in the follow-up period were used to measure nonpharmacological pain management use. Modified Poisson models were used to estimate adjusted prevalence ratios (aPR) and 95% confidence intervals (CI) for age, gender, race and ethnicity, cognitive and physical impairment, and long-term opioid use. Of all long-stay residents, 32.4% were prescribed any opioid, and 15.5% were prescribed opioids long-term. Opioid users (versus nonusers) were more commonly prescribed pain adjuvants (32.9% vs 14.9%), other pain medications (25.5% vs 11.0%), and nonpharmacological pain management (24.5% vs 9.3%). Long-term opioid use was higher in women (aPR = 1.21, 95% CI = 1.18-1.23) and lower in racial and ethnic minorities (non-Hispanic blacks vs whites: APR = 0.93, 95% CI = 0.90-0.94) and those with severe cognitive impairment (vs no or mild impairment, aPR = 0.82, 95% CI = 0.79-0.83). One in seven NH residents was prescribed opioids long-term. Recent guidelines on opioid prescribing for pain recommend reducing long-term opioid use, but this is challenging in NHs because residents may not benefit from nonpharmacological and nonopioid interventions. Studies to address concerns about opioid safety and effectiveness (e.g., on pain and functional status) in NHs are needed. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics

Short- and long-term functional plasticity of white matter induced by oligodendrocyte depolarization in the hippocampus.

PubMed

Yamazaki, Yoshihiko; Fujiwara, Hiroki; Kaneko, Kenya; Hozumi, Yasukazu; Xu, Ming; Ikenaka, Kazuhiro; Fujii, Satoshi; Tanaka, Kenji F

2014-08-01

Plastic changes in white matter have received considerable attention in relation to normal cognitive function and learning. Oligodendrocytes and myelin, which constitute the white matter in the central nervous system, can respond to neuronal activity with prolonged depolarization of membrane potential and/or an increase in the intracellular Ca(2+) concentration. Depolarization of oligodendrocytes increases the conduction velocity of an action potential along axons myelinated by the depolarized oligodendrocytes, indicating that white matter shows functional plasticity, as well as structural plasticity. However, the properties and mechanism of oligodendrocyte depolarization-induced functional plastic changes in white matter are largely unknown. Here, we investigated the functional plasticity of white matter in the hippocampus using mice with oligodendrocytes expressing channelrhodopsin-2. Using extracellular recordings of compound action potentials at the alveus of the hippocampus, we demonstrated that light-evoked depolarization of oligodendrocytes induced early- and late-onset facilitation of axonal conduction that was dependent on the magnitude of oligodendrocyte depolarization; the former lasted for approximately 10 min, whereas the latter continued for up to 3 h. Using whole-cell recordings from CA1 pyramidal cells and recordings of antidromic action potentials, we found that the early-onset short-lasting component included the synchronization of action potentials. Moreover, pharmacological analysis demonstrated that the activation of Ba(2+) -sensitive K(+) channels was involved in early- and late-onset facilitation, whereas 4-aminopyridine-sensitive K(+) channels were only involved in the early-onset component. These results demonstrate that oligodendrocyte depolarization induces short- and long-term functional plastic changes in the white matter of the hippocampus and plays active roles in brain functions. © 2014 Wiley Periodicals, Inc.

Role of "Aplysia" Cell Adhesion Molecules during 5-HT-Induced Long-Term Functional and Structural Changes

ERIC Educational Resources Information Center

Han, Jin-Hee; Lim, Chae-Seok; Lee, Yong-Seok; Kandel, Eric R.; Kaang, Bong-Kiun

2004-01-01

We previously reported that five repeated pulses of 5-HT lead to down-regulation of the TM-apCAM isoform at the surface of "Aplysia" sensory neurons (SNs). We here examined whether apCAM down-regulation is required for 5-HT-induced long-term facilitation. We also analyzed the role of the cytoplasmic and extracellular domains by overexpressing…

Long-term priority effects among insects and fungi colonizing decaying wood.

PubMed

Weslien, Jan; Djupström, Line B; Schroeder, Martin; Widenfalk, Olof

2011-11-01

1. Priority effects have been hypothesized to have long-lasting impact on community structure in natural ecosystems. Long-term studies of priority effects in natural ecosystems are however sparse, especially in terrestrial ecosystems. 2. Wood decay is a slow process involving a high diversity of insect and fungus species. Species interactions that drive change in communities of insects and fungi during wood decay are poorly understood because of a lack of sufficient long-term studies. 3. In this paper, we followed the colonization and succession of wood-living insects and fungi on cut trees during 15 years, from tree death and onwards, in a boreal forest landscape. We test the long-term priority effects hypothesis that the identity and abundance of species that colonize first affect the colonization success of later-arriving species. We also hypothesize that species interact in both facilitative and inhibitory ways, which ultimately affect habitat quality for a red-listed late-succession beetle species. 4. Possible causal associations between species were explored by path analysis. The results indicate that one bark beetle species, Hylurgops palliatus, and one wood-borer species, Monochamus sutor, which colonized the wood during the first year after cutting, influenced the occurrence of a rare, wood-living beetle, Peltis grossa, that started to emerge from the stumps about 10 years later. The positive effects of Hylurgops palliatus and negative effects of M. sutor were largely mediated through the wood-decaying fungus species Fomitopsis pinicola. 5. The study shows that variable priority effects may have long-lasting impact on community assembly in decaying wood. The study also exemplifies new possibilities for managing populations of threatened species by exploring links between early, well-understood species guilds and late, more poorly understood species guilds. © 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society.

Acid Mine Drainage Passive Remediation: Potential Use of Alkaline Clay, Optimal Mixing Ratio and Long Term Impacts

NASA Astrophysics Data System (ADS)

Plaza, F.; Liang, X.; Wen, Y.; Perone, H.

2015-12-01

Acid mine drainage (AMD) is one of the most adverse environmental problems of the mine industry. Surface water and ground water affected by this pollution are characterized by their acidity and the high content of sulfates and heavy metals. In this study, alkaline clay, an industrial waste with a high pH, which is utilized in the alumina refining process, was used as the remediation material to inhibit pyrite oxidation. Through a series of batch and column experiments, complemented with field measurements and geochemical modeling, three important issues associated with this passive and auto sustainable acid mine drainage remediation method were investigated: 1) the potential use of alkaline clay as an AMD remediation material, 2) the adequate alkaline clay/coal refuse mixing ratio (AC/CR) to ensure pH values near to neutral conditions, and, 3) the prediction of long term impacts, in terms of the trends of the main parameters involved in this process such as pH, concentrations of sulfate, iron and other dissolved contaminants. Both field measurements and the samples used for the experiments came from a coal waste site located in Mather, Pennsylvania. Alkaline clay proved to be an effective remediation material for AMD. It was found that 10% AC/CR is an adequate mixing ratio (i.e. the upper limit), which has been also indicated by field measurements. The concentrations of some contaminants such as iron, manganese or sulfate are significantly reduced with the remediation approach, compared to those representative concentrations found in mine tailings. Moreover, results suggest a very reliable long-term stability of the remediation (i.e. neutral pH conditions are maintained), thus enhancing the generation of iron precipitates that could produce pyrite grain coating and hardpan (i.e. cemented layer) on the surface. These processes also made the amended layer less porous, thus increasing water retention and hindering oxygen diffusion.

Long-term exposure to particulate matter, NO2 and the oxidative potential of particulates and diabetes prevalence in a large national health survey.

PubMed

Strak, Maciej; Janssen, Nicole; Beelen, Rob; Schmitz, Oliver; Vaartjes, Ilonca; Karssenberg, Derek; van den Brink, Carolien; Bots, Michiel L; Dijst, Martin; Brunekreef, Bert; Hoek, Gerard

2017-11-01

The evidence from observational epidemiological studies of a link between long-term air pollution exposure and diabetes prevalence and incidence is currently mixed. Some studies found the strongest associations of diabetes with fine particles, other studies with nitrogen dioxide and some studies found no associations. Our aim was to investigate associations between long-term exposure to multiple air pollutants and diabetes prevalence in a large national survey in the Netherlands. We performed a cross-sectional analysis using the 2012 Dutch national health survey to investigate the associations between the 2009 annual average concentrations of multiple air pollutants (PM 10 , PM 2.5 , PM 10-2.5 , PM 2.5 absorbance, OP DTT , OP ESR and NO 2 ) and diabetes prevalence, among 289,703 adults. Air pollution exposure was assessed by land use regression models. Diabetes was defined based on a combined measure of self-reported physician diagnosis and medication prescription from an external database. Using logistic regression, we adjusted for potential confounders, including neighborhood- and individual socio-economic status and lifestyle-related risk factors such as smoking habits, alcohol consumption, physical activity and BMI. After adjustment for potential confounders, all pollutants (except PM 2.5 ) were associated with diabetes prevalence. In two-pollutant models, NO 2 and OP DTT remained associated with increased diabetes prevalence. For NO 2 and OP DTT , single-pollutant ORs per interquartile range were 1.07 (95% CI: 1.05, 1.09) and 1.08 (95% CI: 1.05, 1.10), respectively. Stratified analysis showed no consistent effect modification by any of the included known diabetes risk factors. Long-term residential air pollution exposure was associated with diabetes prevalence in a large health survey in the Netherlands, strengthening the evidence of air pollution being an important diabetes risk factor. Most consistent associations were observed for NO 2 and oxidative

Complex network structure influences processing in long-term and short-term memory.

PubMed

Vitevitch, Michael S; Chan, Kit Ying; Roodenrys, Steven

2012-07-01

Complex networks describe how entities in systems interact; the structure of such networks is argued to influence processing. One measure of network structure, clustering coefficient, C, measures the extent to which neighbors of a node are also neighbors of each other. Previous psycholinguistic experiments found that the C of phonological word-forms influenced retrieval from the mental lexicon (that portion of long-term memory dedicated to language) during the on-line recognition and production of spoken words. In the present study we examined how network structure influences other retrieval processes in long- and short-term memory. In a false-memory task-examining long-term memory-participants falsely recognized more words with low- than high-C. In a recognition memory task-examining veridical memories in long-term memory-participants correctly recognized more words with low- than high-C. However, participants in a serial recall task-examining redintegration in short-term memory-recalled lists comprised of high-C words more accurately than lists comprised of low-C words. These results demonstrate that network structure influences cognitive processes associated with several forms of memory including lexical, long-term, and short-term.

Facilitation and refractoriness of the electrically evoked compound action potential.

PubMed

Hey, Matthias; Müller-Deile, Joachim; Hessel, Horst; Killian, Matthijs

2017-11-01

In this study we aim to resolve the contributions of facilitation and refractoriness at very short pulse intervals. Measurements of the refractory properties of the electrically evoked compound action potential (ECAP) of the auditory nerve in cochlear implant (CI) users at inter pulse intervals below 300 μs are influenced by facilitation and recovery effects. ECAPs were recorded using masker pulses with a wide range of current levels relative to the probe pulse levels, for three suprathreshold probe levels and pulse intervals from 13 to 200 μs. Evoked potentials were measured for 21 CI patients by using the masked response extraction artifact cancellation procedure. During analysis of the measurements the stimulation current was not used as absolute value, but in relation to the patient's individual ECAP threshold. This enabled a more general approach to describe facilitation as a probe level independent effect. Maximum facilitation was found for all tested inter pulse intervals at masker levels near patient's individual ECAP threshold, independent from probe level. For short inter pulse intervals an increased N 1 P 1 amplitude was measured for subthreshold masker levels down to 120 CL below patient's individual ECAP threshold in contrast to the recreated state. ECAPs recorded with inter pulse intervals up to 200 μs are influenced by facilitation and recovery. Facilitation effects are most pronounced for masker levels at or below ECAP threshold, while recovery effects increase with higher masker levels above ECAP threshold. The local maximum of the ECAP amplitude for masker levels around ECAP threshold can be explained by the mutual influence of maximum facilitation and minimal refractoriness. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Self-reported immature defense style as a predictor of outcome in short-term and long-term psychotherapy

PubMed Central

Laaksonen, Maarit A; Sirkiä, Carlos; Knekt, Paul; Lindfors, Olavi

2014-01-01

Objective Identification of pretreatment patient characteristics predictive of psychotherapy outcome could help to guide treatment choices. This study evaluates patients' initial level of immature defense style as a predictor of the outcome of short-term versus long-term psychotherapy. Method In the Helsinki Psychotherapy Study, 326 adult outpatients with mood or anxiety disorder were randomized to individual short-term (psychodynamic or solution-focused) or long-term (psychodynamic) psychotherapy. Their defense style was assessed at baseline using the 88-item Defense Style Questionnaire and classified as low or high around the median value of the respective score. Both specific (Beck Depression Inventory [BDI], Hamilton Depression Rating Scale [HDRS], Symptom Check List Anxiety Scale [SCL-90-Anx], Hamilton Anxiety Rating Scale [HARS]) and global (Symptom Check List Global Severity Index [SCL-90-GSI], Global Assessment of Functioning Scale [GAF]) psychiatric symptoms were measured at baseline and 3–7 times during a 3-year follow-up. Results Patients with high use of immature defense style experienced greater symptom reduction in long-term than in short-term psychotherapy by the end of the 3-year follow-up (50% vs. 34%). Patients with low use of immature defense style experienced faster symptom reduction in short-term than in long-term psychotherapy during the first year of follow-up (34% vs. 19%). Conclusion Knowledge of patients' initial level of immature defense style may potentially be utilized in tailoring treatments. Further research on defense styles as outcome predictors in psychotherapies of different types is needed. PMID:25161816

Facilitated diffusion in chromatin lattices: mechanistic diversity and regulatory potential.

PubMed

Kampmann, Martin

2005-08-01

The interaction between a protein and a specific DNA site is the molecular basis for vital processes in all organisms. Location of the DNA target site by the protein commonly involves facilitated diffusion. Mechanisms of facilitated diffusion vary among proteins; they include one- and two-dimensional sliding along DNA, direct transfer between uncorrelated sites, as well as combinations of these mechanisms. Facilitated diffusion has almost exclusively been studied in vitro. This review discusses facilitated diffusion in the context of the living cell and proposes a theoretical model for facilitated diffusion in chromatin lattices. Chromatin structure differentially affects proteins in different modes of diffusion. The interplay of facilitated diffusion and chromatin structure can determine the rate of protein association with the target site, the frequency of association-dissociation events at the target site, and, under particular conditions, the occupancy of the target site. Facilitated diffusion is required in vivo for efficient DNA repair and bacteriophage restriction and has potential roles in fine-tuning gene regulatory networks and kinetically compartmentalizing the eukaryotic nucleus.

Long-term high-intensity sound stimulation inhibits h current (Ih ) in CA1 pyramidal neurons.

PubMed

Cunha, A O S; Ceballos, C C; de Deus, J L; Leão, R M

2018-05-19

Afferent neurotransmission to hippocampal pyramidal cells can lead to long-term changes to their intrinsic membrane properties and affect many ion currents. One of the most plastic neuronal currents is the hyperpolarization activated cationic current (I h ), which changes in CA1 pyramidal cells in response to many types of physiological and pathological processes, including auditory stimulation. Recently we demonstrated that long-term potentiation (LTP) in rat hippocampal Schaffer-CA1 synapses is depressed by high-intensity sound stimulation. Here we investigated if a long-term high-intensity sound stimulation could affect intrinsic membrane properties of rat CA1 pyramidal neurons. Our results showed that I h is depressed by long-term high intensity sound exposure (1 minute of 110 dB sound, applied two times per day for 10 days). This resulted in a decreased resting membrane potential, increased membrane input resistance and time constant, and decreased action potential threshold. In addition, CA1 pyramidal neurons from sound-exposed animals fired more action potentials than neurons from control animals; However, this effect was not caused by a decreased I h . Interestingly, a single episode (1 minute) of 110 dB sound stimulation which also inhibits hippocampal LTP did not affect I h and firing in pyramidal neurons, suggesting that effects on I h are long-term responses to high intensity sound exposure. Our results show that prolonged exposure to high-intensity sound affects intrinsic membrane properties of hippocampal pyramidal neurons, mainly by decreasing the amplitude of I h . This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Using electrophysiology to demonstrate that cuing affects long-term memory storage over the short term

PubMed Central

Maxcey, Ashleigh M.; Fukuda, Keisuke; Song, Won S.; Woodman, Geoffrey F.

2015-01-01

As researchers who study working memory, we often assume that participants keep a representation of an object in working memory when we present a cue that indicates that object will be tested in a couple of seconds. This intuitively accounts for how well people can remember a cued object relative to their memory for that same object presented without a cue. However, it is possible that this superior memory does not purely reflect storage of the cued object in working memory. We tested the hypothesis that cued presented during a stream of objects, followed by a short retention interval and immediate memory test, change how information is handled by long-term memory. We tested this hypothesis using a family of frontal event-related potentials (ERPs) believed to reflect long-term memory storage. We found that these frontal indices of long-term memory were sensitive to the task relevance of objects signaled by auditory cues, even when objects repeat frequently such that proactive interference was high. Our findings indicate the problematic nature of assuming process purity in the study of working memory, and demonstrate how frequent stimulus repetitions fail to isolate the role of working memory mechanisms. PMID:25604772

Using electrophysiology to demonstrate that cueing affects long-term memory storage over the short term.

PubMed

Maxcey, Ashleigh M; Fukuda, Keisuke; Song, Won S; Woodman, Geoffrey F

2015-10-01

As researchers who study working memory, we often assume that participants keep a representation of an object in working memory when we present a cue that indicates that the object will be tested in a couple of seconds. This intuitively accounts for how well people can remember a cued object, relative to their memory for that same object presented without a cue. However, it is possible that this superior memory does not purely reflect storage of the cued object in working memory. We tested the hypothesis that cues presented during a stream of objects, followed by a short retention interval and immediate memory test, can change how information is handled by long-term memory. We tested this hypothesis by using a family of frontal event-related potentials believed to reflect long-term memory storage. We found that these frontal indices of long-term memory were sensitive to the task relevance of objects signaled by auditory cues, even when the objects repeated frequently, such that proactive interference was high. Our findings indicate the problematic nature of assuming process purity in the study of working memory, and demonstrate that frequent stimulus repetitions fail to isolate the role of working memory mechanisms.

Predicting Discharge to Institutional Long-Term Care After Stroke: A Systematic Review and Metaanalysis.

PubMed

Burton, Jennifer K; Ferguson, Eilidh E C; Barugh, Amanda J; Walesby, Katherine E; MacLullich, Alasdair M J; Shenkin, Susan D; Quinn, Terry J

2018-01-01

Stroke is a leading cause of disability worldwide, and a significant proportion of stroke survivors require long-term institutional care. Understanding who cannot be discharged home is important for health and social care planning. Our aim was to establish predictive factors for discharge to institutional care after hospitalization for stroke. We registered and conducted a systematic review and meta-analysis (PROSPERO: CRD42015023497) of observational studies. We searched MEDLINE, EMBASE, and CINAHL Plus to February 2017. Quantitative synthesis was performed where data allowed. Acute and rehabilitation hospitals. Adults hospitalized for stroke who were newly admitted directly to long-term institutional care at the time of hospital discharge. Factors associated with new institutionalization. From 10,420 records, we included 18 studies (n = 32,139 participants). The studies were heterogeneous and conducted in Europe, North America, and East Asia. Eight studies were at high risk of selection bias. The proportion of those surviving to discharge who were newly discharged to long-term care varied from 7% to 39% (median 17%, interquartile range 12%), and the model of care received in the long-term care setting was not defined. Older age and greater stroke severity had a consistently positive association with the need for long-term care admission. Individuals who had a severe stroke were 26 times as likely to be admitted to long-term care than those who had a minor stroke. Individuals aged 65 and older had a risk of stroke that was three times as great as that of younger individuals. Potentially modifiable factors were rarely examined. Age and stroke severity are important predictors of institutional long-term care admission directly from the hospital after an acute stroke. Potentially modifiable factors should be the target of future research. Stroke outcome studies should report discharge destination, defining the model of care provided in the long-term care setting. �

78 FR 66945 - Proposed Collection; 60-Day Comment request: Gulf Long-Term Follow-Up Study (GuLF STUDY)

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-07

... Comment request: Gulf Long-Term Follow-Up Study (GuLF STUDY) Summary: In compliance with the requirement... days of the date of this publication. Proposed Collection: Gulf Long-Term Follow-Up Study (GuLF STUDY... GuLF STUDY is to investigate potential short- and long-term health effects associated with oil spill...

Small mammals as indicators of short-term and long-term disturbance in mixed prairie

USGS Publications Warehouse

Leis, S.A.; Leslie, David M.; Engle, David M.; Fehmi, J.S.

2008-01-01

Disturbance by military maneuvers over short and long time scales may have differential effects on grassland communities. We assessed small mammals as indicators of disturbance by military maneuvers in a mixed prairie in southern Oklahoma USA. We examined sites on two soil series, Foard and Lawton, across a gradient of disturbance intensity. A MANOVA showed that abundance of small mammals was associated (p = 0.03) with short-term (cover of vehicle tracks) disturbance but was not associated (p = 0.12) with long-term (loss of soil organic carbon, SOC) disturbance intensity. At the individual species level, Sigmodon hispidus (cotton rat) and Peromyscus maniculatus (deer mouse) occurred across all levels of disturbance and in both soil types. Only P. maniculatus abundance changed (p < 0.01) with short-term disturbance and increased by about one individual per 5% of additional track-cover. Abundance of P. maniculatus also increased (p = 0.04) by about three individuals per 1% increase in soil carbon. Chaetodipus hispidus (hispid pocket mouse) and Reithrodontomys fulvescens (fulvous harvest mouse) only occurred in single soil types limiting their potential as more general indicators. Abundance of P. maniculatus was positively related to shifts in plant species composition and likely reflected changes in vegetation structure (i.e. litter depth) and forage availability resulting from disturbance. Peromyscus maniculatus may be a useful biological indicator of ecosystem change because it responded predictably to both long-term and short-term disturbance and, when coupled with soil, plant, and disturbance history variables, can reveal land condition trends. ?? Springer Science+Business Media B.V. 2007.

Global estimation of long-term persistence in annual river runoff

NASA Astrophysics Data System (ADS)

Markonis, Y.; Moustakis, Y.; Nasika, C.; Sychova, P.; Dimitriadis, P.; Hanel, M.; Máca, P.; Papalexiou, S. M.

2018-03-01

Long-term persistence (LTP) of annual river runoff is a topic of ongoing hydrological research, due to its implications to water resources management. Here, we estimate its strength, measured by the Hurst coefficient H, in 696 annual, globally distributed, streamflow records with at least 80 years of data. We use three estimation methods (maximum likelihood estimator, Whittle estimator and least squares variance) resulting in similar mean values of H close to 0.65. Subsequently, we explore potential factors influencing H by two linear (Spearman's rank correlation, multiple linear regression) and two non-linear (self-organizing maps, random forests) techniques. Catchment area is found to be crucial for medium to larger watersheds, while climatic controls, such as aridity index, have higher impact to smaller ones. Our findings indicate that long-term persistence is weaker than found in other studies, suggesting that enhanced LTP is encountered in large-catchment rivers, were the effect of spatial aggregation is more intense. However, we also show that the estimated values of H can be reproduced by a short-term persistence stochastic model such as an auto-regressive AR(1) process. A direct consequence is that some of the most common methods for the estimation of H coefficient, might not be suitable for discriminating short- and long-term persistence even in long observational records.

Priming of Short-Term Potentiation and Synaptic Tagging/Capture Mechanisms by Ryanodine Receptor Activation in Rat Hippocampal CA1

ERIC Educational Resources Information Center

Sajikumar, Sreedharan; Li, Qin; Abraham, Wickliffe C.; Xiao, Zhi Cheng

2009-01-01

Activity-dependent changes in synaptic strength such as long-term potentiation (LTP) and long-term depression (LTD) are considered to be cellular mechanisms underlying learning and memory. Strengthening of a synapse for a few seconds or minutes is termed short-term potentiation (STP) and is normally unable to take part in the processes of synaptic…

Human Endothelial Cells: Use of Heparin in Cloning and Long-Term Serial Cultivation

NASA Astrophysics Data System (ADS)

Thornton, Susan C.; Mueller, Stephen N.; Levine, Elliot M.

1983-11-01

Endothelial cells from human blood vessels were cultured in vitro, with doubling times of 17 to 21 hours for 42 to 79 population doublings. Cloned human endothelial cell strains were established for the first time and had similar proliferative capacities. This vigorous cell growth was achieved by addition of heparin to culture medium containing reduced concentrations of endothelial cell growth factor. The routine cloning and long-term culture of human endothelial cells will facilitate studying the human endothelium in vitro.

Medical Underwriting In Long-Term Care Insurance: Market Conditions Limit Options For Higher-risk Consumers

PubMed Central

2016-01-01

A key feature of private long-term care insurance is that medical underwriters screen out would-be buyers who have health conditions that portend near-term physical or cognitive disability. We applied common underwriting criteria based on data from two long-term care insurers to a nationally representative sample of individuals in the target age range for long-term care insurance (50–71 years of age). The screening criteria put upper bounds on the current proportion of Americans who could gain coverage in the individual market without changes to medical underwriting practice. Specifically, our simulations show that, for the target age range, approximately 30% of individuals whose wealth meets minimum industry standards for the suitability of long-term care insurance would have their long-term care insurance application rejected for medical reasons. Among the general population–without considering restrictions on wealth–we estimate that 40% would be disqualified. In evaluating long-term care financing reforms and their potential to increase private insurance rates, as well as to reduce financial pressure on public safety-net programs, policymakers need to consider the role of underwriting in the market for long-term care insurance. PMID:27503976

Emotional and Cognitive Information Processing: Relations to Behavioral Performance and Hippocampal Long-Term Potentiation In Vivo during a Spatial Water Maze Training in Rats

ERIC Educational Resources Information Center

Schulz, Kristina; Korz, Volker

2010-01-01

Emotionality as well as cognitive abilities contribute to the acquisition and retrieval of memories as well as to the consolidation of long-term potentiation (LTP), a cellular model of memory formation. However, little is known about the timescale and relative contribution of these processes. Therefore, we tested the effects of weak water maze…

Interleukin 1 beta inhibits synaptic strength and long-term potentiation in the rat CA1 hippocampus.

PubMed

Bellinger, F P; Madamba, S; Siggins, G R

1993-11-19

Cytokines such as interleukin-1 beta (IL-1 beta) are released in the nervous system following inflammation or infection. Recently, IL-1 beta was shown to enhance synaptic inhibitory mechanisms. We therefore investigated the effect of IL-1 beta superfusion on long-term potentiation (LTP), the cellular model of memory and learning, evoked in the CA1 region by tetanic stimulation of the stratum radiatum in the rat hippocampal slice. IL-1 beta (150 pM-1.5 nM) superfused 10 min before tetanic stimulation significantly reduced LTP of the slope of the population excitatory postsynaptic potential (pEPSP) and the population spike (PS) amplitude in CA1 in a concentration-dependent manner. IL-1 beta (1.5 nM) applied for 10 min 1 h before tetanus significantly inhibited LTP of the PS amplitude and pEPSP slope and reduced pEPSP and PS values before tetanus as well, although the PS returned to control values before tetanus. Heat-inactivated IL-1 beta had no effect on pre-tetanus pEPSP or PS values or the induction of LTP. These data demonstrate that IL-1 beta modulates synaptic potentials and reduces LTP. These findings have important implications for the role of IL-1 beta in neuronal disorders following infection, perhaps best exemplified by HIV-1-associated dementia.

Long-Term Dynamics of Autonomous Fractional Differential Equations

NASA Astrophysics Data System (ADS)

Liu, Tao; Xu, Wei; Xu, Yong; Han, Qun

This paper aims to investigate long-term dynamic behaviors of autonomous fractional differential equations with effective numerical method. The long-term dynamic behaviors predict where systems are heading after long-term evolution. We make some modification and transplant cell mapping methods to autonomous fractional differential equations. The mapping time duration of cell mapping is enlarged to deal with the long memory effect. Three illustrative examples, i.e. fractional Lotka-Volterra equation, fractional van der Pol oscillator and fractional Duffing equation, are studied with our revised generalized cell mapping method. We obtain long-term dynamics, such as attractors, basins of attraction, and saddles. Compared with some existing stability and numerical results, the validity of our method is verified. Furthermore, we find that the fractional order has its effect on the long-term dynamics of autonomous fractional differential equations.

Hormonal and Monoamine Signaling during Reinforcement of Hippocampal Long-Term Potentiation and Memory Retrieval

ERIC Educational Resources Information Center

Korz, Volker; Frey, Julietta U.

2007-01-01

Recently it was shown that holeboard training can reinforce, i.e., transform early-LTP into late-LTP in the dentate gyrus during the initial formation of a long-term spatial reference memory in rats. The consolidation of LTP as well as of the reference memory was dependent on protein synthesis. We have now investigated the transmitter systems…

The Womanly World of Long Term Care: The Plight of the Long Term Care Worker. Gray Paper.

ERIC Educational Resources Information Center

Older Women's League, Washington, DC.

Long-term care workers (those who are paid to provide custodial care for long-term patients in nursing homes or at home) must care for a growing number of increasingly disabled or dependent persons. They are working for agencies and institutions under growing pressure to increase productivity. They face new training and competency requirements,…

Never mind the length, feel the quality: The Impact of Long-term Epidemiological Data Sets on Theory, Application and Policy

PubMed Central

Rohani, Pejman; King, Aaron A.

2010-01-01

Infectious diseases have been a prime testing ground for ecological theory. At the same time, the ecological perspective is increasingly recognized as essential in epidemiology. Long-term, spatially-resolved, reliable disease incidence data and the ability to confront them with mechanistic models have been critical in this cross-fertilization. Here, we review some of the key intellectual developments in epidemiology facilitated by long-term data. We proceed to identify research frontiers at the interface of ecology and epidemiology and their associated data needs. PMID:20800928

Long-term, correlated emittance decrease in intense, high-brightness induction linacs

NASA Astrophysics Data System (ADS)

Carlsten, Bruce E.

1999-09-01

Simulations of high-brightness induction linacs often show a slow, long-term emittance decrease as the beam is matched from the electron gun into the linac. Superimposed on this long-term decrease are rapid emittance oscillations. These effects can be described in terms of correlations in the beam's radial phase space. The rapid emittance oscillations are due to transverse plasma oscillations, which stay nearly in phase for different radial positions within the beam. The initial emittance, just after the electron gun, is dominated by nonlinear focusing within the gun introduced by the anode exit hole. Due to the large space-charge force of an intense electron beam, the focusing of the beam through the matching section introduces an effective nonlinear force (from the change in the particles' potential energies) which counteracts the nonlinearities from the electron gun, leading to an average, long-term emittance decrease. Not all of the initial nonlinearity is removed by the matching procedure, and there are important consequences both for emittance measurements using solenoid focal length scans and for focusing the electron beam to a target.

Exploring views on long term rehabilitation for people with stroke in a developing country: findings from focus group discussions

PubMed Central

2014-01-01

Background The importance of long term rehabilitation for people with stroke is increasingly evident, yet it is not known whether such services can be materialised in countries with limited community resources. In this study, we explored the perception of rehabilitation professionals and people with stroke towards long term stroke rehabilitation services and potential approaches to enable provision of these services. Views from providers and users are important in ensuring whatever strategies developed for long term stroke rehabilitations are feasible and acceptable. Methods Focus group discussions were conducted involving 15 rehabilitation professionals and eight long term stroke survivors. All recorded conversations were transcribed verbatim and analysed using the principles of qualitative research. Results Both groups agreed that people with stroke may benefit from more rehabilitation compared to the amount of rehabilitation services presently provided. Views regarding the unavailability of long term rehabilitation services due to multi-factorial barriers were recognised. The groups also highlighted the urgent need for the establishment of community-based stroke rehabilitation centres. Family-assisted home therapy was viewed as a potential approach to continued rehabilitation for long term stroke survivors, given careful planning to overcome several family-related issues. Conclusions Barriers to the provision of long term stroke rehabilitation services are multi-factorial. Establishment of community-based stroke rehabilitation centres and training family members to conduct home-based therapy are two potential strategies to enable the continuation of rehabilitation for long term stroke survivors. PMID:24606911

Long-term high-fat feeding induces greater fat storage in mice lacking UCP3.

PubMed

Costford, Sheila R; Chaudhry, Shehla N; Crawford, Sean A; Salkhordeh, Mahmoud; Harper, Mary-Ellen

2008-11-01

Uncoupling protein-3 (UCP3) is a mitochondrial inner-membrane protein highly expressed in skeletal muscle. While UCP3's function is still unknown, it has been hypothesized to act as a fatty acid (FA) anion exporter, protecting mitochondria against lipid peroxidation and/or facilitating FA oxidation. The aim of this study was to determine the effects of long-term feeding of a 45% fat diet on whole body indicators of muscle metabolism in congenic C57BL/6 mice that were either lacking UCP3 (Ucp3(-/-)) or had a transgenically induced approximately twofold increase in UCP3 levels (UCP3tg). Mice were fed the high-fat (HF) diet for a period of either 4 or 8 mo immediately following weaning. After long-term HF feeding, UCP3tg mice weighed an average of 15% less than wild-type mice (P < 0.05) and were 20% less metabolically efficient than both wild-type and Ucp3(-/-) mice (P < 0.01). Additionally, wild-type mice had 21% lower, whereas UCP3tg mice had 36% lower, levels of adiposity compared with Ucp3(-/-) mice (P < 0.05 and P < 0.001, respectively), indicating a protective effect of UCP3 against fat gain. No differences in whole body oxygen consumption were detected following long-term HF feeding. Glucose and insulin tolerance tests revealed that both the UCP3tg and Ucp3(-/-) mice were more glucose tolerant and insulin sensitive compared with wild-type mice after short-term HF feeding, but this protection was not maintained in the long term. Findings indicate that UCP3 is involved in protection from fat gain induced by long-term HF feeding, but not in protection from insulin resistance.

Selective effects of aniracetam across receptor types and forms of synaptic facilitation in hippocampus.

PubMed

Xiao, P; Staubli, U; Kessler, M; Lynch, G

1991-10-01

Aniracetam reversibly increased synaptic responses mediated by the AMPA but not the NMDA subclass of glutamate receptors in hippocampus and was considerably more potent than structurally similar nootropics. The drug had greater effects on field excitatory postsynaptic potentials (EPSPs) in the dentate gyrus and CA1 region than it did in the CA3 region, suggesting that it differentiates between variants of the AMPA receptor. Ligand binding to glutamate receptors in synaptosomal membrane fractions was minimally changed by aniracetam. Finally, the percent facilitation produced by aniracetam in the CA1 region was not reduced by any of three treatments (4-aminopyridine, changes in extracellular calcium concentrations, paired-pulse stimulation) that affect release but, in accord with a previous report, was substantially decreased by long-term potentiation. These results support the conclusion that aniracetam selectively increases the conductance of a subgroup of synaptic AMPA receptors in hippocampus and suggest that receptor changes underlie the expression of long-term potentiation.

The role of long-term memory in a test of visual working memory: Proactive facilitation but no proactive interference.

PubMed

Oberauer, Klaus; Awh, Edward; Sutterer, David W

2017-01-01

We report 4 experiments examining whether associations in visual working memory are subject to proactive interference from long-term memory (LTM). Following a long-term learning phase in which participants learned the colors of 120 unique objects, a working memory (WM) test was administered in which participants recalled the precise colors of 3 concrete objects in an array. Each array in the WM test consisted of 1 old (previously learned) object with a new color (old-mismatch), 1 old object with its old color (old-match), and 1 new object. Experiments 1 to 3 showed that WM performance was better in the old-match condition than in the new condition, reflecting a beneficial contribution from LTM. In the old-mismatch condition, participants sometimes reported colors associated with the relevant shape in LTM, but the probability of successful recall was equivalent to that in the new condition. Thus, information from LTM only intruded in the absence of reportable information in WM. Experiment 4 tested for, and failed to find, proactive interference from the preceding trial in the WM test: Performance in the old-mismatch condition, presenting an object from the preceding trial with a new color, was equal to performance with new objects. Experiment 5 showed that long-term memory for object-color associations is subject to proactive interference. We conclude that the exchange of information between LTM and WM appears to be controlled by a gating mechanism that protects the contents of WM from proactive interference but admits LTM information when it is useful. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Long-term studies of dopamine agonists.

PubMed

Hubble, Jean P

2002-02-26

Dopamine agonists have long been used as adjunctive therapy for the treatment of Parkinson's disease (PD). In more recent years these drugs have also been proved safe and effective as initial therapy in lieu of levodopa in the treatment of PD. Long-term levodopa therapy is associated with motor complications, including fluctuating response patterns and dyskinesia. By initially introducing a dopamine agonist as symptomatic drug therapy, it may be possible to postpone the use of levodopa and delay or prevent the development of motor complications. Recently, four clinical trials have explored this hypothesis by comparing the long-term response and side effects of levodopa with dopamine agonist therapy. The drugs studied have included ropinirole, pramipexole, cabergoline, and pergolide. In each of these projects, the occurrence of motor complications, such as wearing off and dyskinesia, was significantly less in the subjects assigned to initiation of therapy with a dopamine agonist. The addition of levodopa could be postponed by many months or even several years. Therefore, these long-term studies of dopamine agonists support the initiation of a dopamine agonist instead of levodopa in an effort to postpone levodopa-related motor complications. This therapeutic approach may be particularly appropriate in PD patients with a long treatment horizon on the basis of age and general good health. The extension phase of the long-term study comparing pramipexole with levodopa is ongoing, and follow-up information may help to establish the value of this treatment strategy.

Internet Interventions for Long-Term Conditions: Patient and Caregiver Quality Criteria

PubMed Central

Murray, Elizabeth; Stevenson, Fiona; Gore, Charles; Nazareth, Irwin

2006-01-01

Background Interactive health communication applications (IHCAs) that combine high-quality health information with interactive components, such as self-assessment tools, behavior change support, peer support, or decision support, are likely to benefit people with long-term conditions. IHCAs are now largely Web-based and are becoming known as "Internet interventions." Although there are numerous professionally generated criteria to assess health-related websites, to date there has been scant exploration of patient-generated assessment criteria even though patients and professionals use different criteria for assessing the quality of traditional sources of health information. Objective We aimed to determine patients' and caregivers' requirements of IHCAs for long-term conditions as well as their criteria for assessing the quality of different programs. Methods This was a qualitative study with focus groups. Patients and caregivers managing long-term conditions used three (predominantly Web-based) IHCAs relevant to their condition and subsequently discussed the strengths and weaknesses of the different IHCAs in focus groups. Participants in any one focus group all shared the same long-term condition and viewed the same three IHCAs. Patient and caregiver criteria for IHCAs emerged from the data. Results There were 40 patients and caregivers who participated in 10 focus groups. Participants welcomed the potential of Internet interventions but felt that many were not achieving their full potential. Participants generated detailed and specific quality criteria relating to information content, presentation, interactivity, and trustworthiness, which can be used by developers and purchasers of Internet interventions. Conclusions The user-generated quality criteria reported in this paper should help developers and purchasers provide Internet interventions that better meet user needs. PMID:16954123

Academic potential and cognitive functioning of long-term survivors after childhood liver transplantation.

PubMed

Ee, L C; Lloyd, O; Beale, K; Fawcett, J; Cleghorn, G J

2014-05-01

This cross-sectional study assessed intellect, cognition, academic function, behaviour, and emotional health of long-term survivors after childhood liver transplantation. Eligible children were >5 yr post-transplant, still attending school, and resident in Queensland. Hearing and neurocognitive testing were performed on 13 transplanted children and six siblings including two twin pairs where one was transplanted and the other not. Median age at testing was 13.08 (range 6.52-16.99) yr; time elapsed after transplant 10.89 (range 5.16-16.37) yr; and age at transplant 1.15 (range 0.38-10.00) yr. Mean full-scale IQ was 97 (81-117) for transplanted children and 105 (87-130) for siblings. No difficulties were identified in intellect, cognition, academic function, and memory and learning in transplanted children or their siblings, although both groups had reduced mathematical ability compared with normal. Transplanted patients had difficulties in executive functioning, particularly in self-regulation, planning and organization, problem-solving, and visual scanning. Thirty-one percent (4/13) of transplanted patients, and no siblings, scored in the clinical range for ADHD. Emotional difficulties were noted in transplanted patients but were not different from their siblings. Long-term liver transplant survivors exhibit difficulties in executive function and are more likely to have ADHD despite relatively intact intellect and cognition. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Calcium sensor regulation of the CaV2.1 Ca2+ channel contributes to long-term potentiation and spatial learning.

PubMed

Nanou, Evanthia; Scheuer, Todd; Catterall, William A

2016-11-15

Many forms of short-term synaptic plasticity rely on regulation of presynaptic voltage-gated Ca 2+ type 2.1 (Ca V 2.1) channels. However, the contribution of regulation of Ca V 2.1 channels to other forms of neuroplasticity and to learning and memory are not known. Here we have studied mice with a mutation (IM-AA) that disrupts regulation of Ca V 2.1 channels by calmodulin and related calcium sensor proteins. Surprisingly, we find that long-term potentiation (LTP) of synaptic transmission at the Schaffer collateral-CA1 synapse in the hippocampus is substantially weakened, even though this form of synaptic plasticity is thought to be primarily generated postsynaptically. LTP in response to θ-burst stimulation and to 100-Hz tetanic stimulation is much reduced. However, a normal level of LTP can be generated by repetitive 100-Hz stimulation or by depolarization of the postsynaptic cell to prevent block of NMDA-specific glutamate receptors by Mg 2+ The ratio of postsynaptic responses of NMDA-specific glutamate receptors to those of AMPA-specific glutamate receptors is decreased, but the postsynaptic current from activation of NMDA-specific glutamate receptors is progressively increased during trains of stimuli and exceeds WT by the end of 1-s trains. Strikingly, these impairments in long-term synaptic plasticity and the previously documented impairments in short-term synaptic plasticity in IM-AA mice are associated with pronounced deficits in spatial learning and memory in context-dependent fear conditioning and in the Barnes circular maze. Thus, regulation of Ca V 2.1 channels by calcium sensor proteins is required for normal short-term synaptic plasticity, LTP, and spatial learning and memory in mice.

New Perspectives on the Affordability of Long-Term Care Insurance and Potential Market Size.

ERIC Educational Resources Information Center

Cohen, Marc A.; And Others

1993-01-01

Examined over 6,000 elderly long-term care insurance purchasers. Found that typical policy sold cost $102 per month, covered five years of nursing home care and paid $69 per day in benefits. Close to one-third of purchasers had incomes under $20,000, 63% used some savings to pay premiums, 37% spent more than 5% of income on policies. (Author/NB)

Early nutrition and health: short- and long-term outcomes.

PubMed

Gruszfeld, Dariusz; Socha, Piotr

2013-01-01

Maternal diet, nutritional status during pregnancy, and the early diet of the offspring play an important role in later health. The short- and long-term outcomes of early nutrition have been extensively studied in recent decades. One of the most commonly investigated nutritional interventions is breastfeeding, which is associated with a number of positive short- and long-term outcomes. A short-term effect of breastfeeding is reduced morbidity and mortality in children from poor living conditions and in preterm infants. Breastfeeding is associated with better cognitive development and also has a long-term protective effect on obesity risk, prevalence of type 2 diabetes, and a lowering effect on blood pressure. Selected nutrients have undergone extensive investigation to show their role in disease prevention or improved development, e.g. protein intake in infancy seems to be associated with a later risk of obesity or docosahexaenoic acid supplementation has a positive impact on cognitive function. Another consideration is the fast catch-up growth in small for gestational age infants as an important factor associated with adult risk of cardiovascular problems. On the other hand, high protein and energy intake seems to be positively associated with some indicators of cognitive development. Most of the evidence comes from observational studies that cannot exclude potential confounders. Animal studies demonstrate causality but should not be directly extrapolated to humans. The number of randomized controlled studies is increasing but long-term follow-ups are necessary to obtain convincing results. The majority of these trials compare different infant formula compositions and macro- or micronutrient supplementation. One of the major questions is to define a critical (or opportunity) window and a mechanism of nutritional influence on several health outcomes. Copyright © 2013 S. Karger AG, Basel.

DEVELOPMENTAL LEAD (PB) EXPOSURE REDUCES THE ABILITY OF THE NNDA ANTAGONIST MK801 TO SUPPRESS LONG-TERM POTENTIATION (LTP) IN THE RAT DENTATE GYRUS, IN VIVO

EPA Science Inventory

Chronic developmental lead (Pb) exposure increases the threshold and enhances decay of long-term potentiation (LTP) in the dentate gyrus of the hippocampal formation. MK-801 and other antagonists of the N-methyl-D-aspartate (NMDA) glutamate receptor subtype impair induction of LT...

Long-term bed degradation in Maryland streams (phase 3, part I) : urban streams in the Piedmont Plateau province, [research summary].

DOT National Transportation Integrated Search

2014-09-01

Estimation of potential long-term down-cutting of the stream bed is necessary for evaluation and design of bridges for scour and culverts for fish passage. Existing guidelines for assessing this potential long-term bed degradation (LTBD) in Maryland ...

Long Term TOA - M Data and Information

Atmospheric Science Data Center

2017-09-06

... A Long-Term TOA and Constrained Surface Radiation Budget Project A Long-Term TOA and Constrained Surface Readiation ... Budget Experiment (ERBE) and Clouds and the Earth's Radiant Energy System (CERES), that span nearly 30 years to date.   The ...

Quality of Life and Functional Health Status of Long-Term Meditators

PubMed Central

Manocha, Ramesh; Black, Deborah; Wilson, Leigh

2012-01-01

Background. There is very little data describing the long-term health impacts of meditation. Aim. To compare the quality of life and functional health of long-term meditators to that of the normative population in Australia. Method. Using the SF-36 questionnaire and a Meditation Lifestyle Survey, we sampled 343 long-term Australian Sahaja Yoga meditation practitioners and compared their scores to those of the normative Australian population. Results. Six SF-36 subscales (bodily pain, general health, mental health, role limitation—emotional, social functioning, and vitality) were significantly better in meditators compared to the national norms whereas two of the subscales (role limitation—physical, physical functioning) were not significantly different. A substantial correlation between frequency of mental silence experience and the vitality, general health, and especially mental health subscales (P < 0.005) was found. Conclusion. Long-term practitioners of Sahaja yoga meditation experience better functional health, especially mental health, compared to the general population. A relationship between functional health, especially mental health, and the frequency of meditative experience (mental silence) exists that may be causal. Evidence for the potential role of this definition of meditation in enhancing quality of life, functional health and wellbeing is growing. Implications for primary mental health prevention are discussed. PMID:22611427

Beyond Quarterly Earnings: Preparing the Business Community for Long-term Climate Risks

NASA Astrophysics Data System (ADS)

Carlson, C.; Goldman, G. T.

2014-12-01

The business community stands to be highly impacted by climate change. In both short and long-term timescales, climate change presents material and financial risks to companies in diverse economic sectors. How the private sector accounts for long-term risks while making short-term decisions about operations is a complex challenge. Companies are accountable to shareholders and must report performance to them on a quarterly basis. At the same time, company investors are exposed to long-term climate-related risks and face losses if companies fail to prepare for climate impacts. The US Securities and Exchange Commission (SEC) obligates publicly traded companies to discuss risks that might materially affect their business and since 2010, the agency recommends that companies consider and discuss any significant risks to their business from climate change. Some companies have complied with this guidance and comprehensively analyze potential climate change impacts, yet others fail to consider climate change at all. Such omissions leave companies without plans for addressing future risks and expose investors and the public to potential catastrophic events from climate change impacts. Climate risk projections can inform companies about the vulnerability of their facilities, supply chains, transportation pathways, and other assets. Such projections can help put climate-related risks in terms of material costs for companies and their investors. Focusing on the vulnerability of coastal facilities, we will use climate change impact projections to demonstrate the economic impacts of climate change faced by the private sector. These risks are then compared to company disclosures to the SEC to assess the degree to which companies have considered their vulnerability to climate change. Finally, we will discuss ways that companies can better assess and manage long-term climate risks.

Long-term biological investigations in space.

PubMed

Lotz, R G; Fuchs, H; Bertsche, U

1975-01-01

Missions in space within the next two decades will be of longer duration than those carried out up to the present time, and the effects of such long-term flights on biological organisms are unknown. Results of biological experiments that have been performed to date cannot be extrapolated to results in future flights because of the unknown influence of adaptation over a long period of time. Prior experiments with Axolotl, fishes, and vertebrates by our research team (in part with sounding rockets) showed that these specimens did not appear to be suitable for long-term missions on which minimization of expense, technique, and energy is required. Subsequent investigations have shown the suitability of the leech (Hirudo medicinalis), which consumes blood of mammals up to ten times its own weight (1 g) and can live more than 2 years without further food supply. Emphasis in the experiments with Hirudo medicinalis is placed on metabolic rhythm and motility. Resorption and diffusion in tissue, development, and growth under long-term effects of cosmic proton radiation and zero-gravity are other focal points. The constancy of cellular life in the mature animals is a point in favor of these specimens. We have also taken into account the synergistic effects of the space environment on the problems just mentioned. The life-support system constructed for the leech has been tested successfully in four sounding rocket flights and, on that basis, has been prepared for a long-term mission. Long-term investigations out of the terrestrial biosphere will provide us with information concerning the degree of adaptation of certain physiological and biochemical functions and as to what extent biological readjustment or repair processes can occur under the specific stress conditions of space flight.

Beyond post-marketing research and MedWatch: Long-term studies of drug risks.

PubMed

Resnik, David B

2007-10-01

Critics of the drug safety system have discussed many different potential reforms, ranging from mandatory registration of clinical trials to increasing the power of regulatory agencies, but few have discussed one of the most important ways of enhancing safety: increasing the number of long-term studies of medications. Long-term studies of the risks and benefits of drugs can provide useful information for regulators, healthcare professionals, and patients. Government funding agencies should lead the effort to conduct long-term studies of drugs, but private companies should also be required to lend financial support. Because cost-effectiveness is likely to be an important consideration in conducting this research, funding agencies should focus, at first, on drugs that are used to treat common, chronic conditions.

Beyond post-marketing research and MedWatch: Long-term studies of drug risks

PubMed Central

Resnik, David B

2007-01-01

Critics of the drug safety system have discussed many different potential reforms, ranging from mandatory registration of clinical trials to increasing the power of regulatory agencies, but few have discussed one of the most important ways of enhancing safety: increasing the number of long-term studies of medications. Long-term studies of the risks and benefits of drugs can provide useful information for regulators, healthcare professionals, and patients. Government funding agencies should lead the effort to conduct long-term studies of drugs, but private companies should also be required to lend financial support. Because cost-effectiveness is likely to be an important consideration in conducting this research, funding agencies should focus, at first, on drugs that are used to treat common, chronic conditions. PMID:19727333

Carbon sequestration is related to mycorrhizal fungal community shifts during long-term succession in boreal forests.

PubMed

Clemmensen, Karina E; Finlay, Roger D; Dahlberg, Anders; Stenlid, Jan; Wardle, David A; Lindahl, Björn D

2015-03-01

Boreal forest soils store a major proportion of the global terrestrial carbon (C) and below-ground inputs contribute as much as above-ground plant litter to the total C stored in the soil. A better understanding of the dynamics and drivers of root-associated fungal communities is essential to predict long-term soil C storage and climate feedbacks in northern ecosystems. We used 454-pyrosequencing to identify fungal communities across fine-scaled soil profiles in a 5000 yr fire-driven boreal forest chronosequence, with the aim of pinpointing shifts in fungal community composition that may underlie variation in below-ground C sequestration. In early successional-stage forests, higher abundance of cord-forming ectomycorrhizal fungi (such as Cortinarius and Suillus species) was linked to rapid turnover of mycelial biomass and necromass, efficient nitrogen (N) mobilization and low C sequestration. In late successional-stage forests, cord formers declined, while ericoid mycorrhizal ascomycetes continued to dominate, potentially facilitating long-term humus build-up through production of melanized hyphae that resist decomposition. Our results suggest that cord-forming ectomycorrhizal fungi and ericoid mycorrhizal fungi play opposing roles in below-ground C storage. We postulate that, by affecting turnover and decomposition of fungal tissues, mycorrhizal fungal identity and growth form are critical determinants of C and N sequestration in boreal forests. © 2014 The Authors New Phytologist © 2014 New Phytologist Trust.

Long-Term Plasticity of Neurotransmitter Release: Emerging Mechanisms and Contributions to Brain Function and Disease.

PubMed

Monday, Hannah R; Younts, Thomas J; Castillo, Pablo E

2018-04-25

Long-lasting changes of brain function in response to experience rely on diverse forms of activity-dependent synaptic plasticity. Chief among them are long-term potentiation and long-term depression of neurotransmitter release, which are widely expressed by excitatory and inhibitory synapses throughout the central nervous system and can dynamically regulate information flow in neural circuits. This review article explores recent advances in presynaptic long-term plasticity mechanisms and contributions to circuit function. Growing evidence indicates that presynaptic plasticity may involve structural changes, presynaptic protein synthesis, and transsynaptic signaling. Presynaptic long-term plasticity can alter the short-term dynamics of neurotransmitter release, thereby contributing to circuit computations such as novelty detection, modifications of the excitatory/inhibitory balance, and sensory adaptation. In addition, presynaptic long-term plasticity underlies forms of learning and its dysregulation participates in several neuropsychiatric conditions, including schizophrenia, autism, intellectual disabilities, neurodegenerative diseases, and drug abuse. Expected final online publication date for the Annual Review of Neuroscience Volume 41 is July 8, 2018. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Synaptic Long-Term Potentiation and Depression in the Rat Medial Vestibular Nuclei Depend on Neural Activation of Estrogenic and Androgenic Signals

PubMed Central

Scarduzio, Mariangela; Panichi, Roberto; Pettorossi, Vito Enrico; Grassi, Silvarosa

2013-01-01

Estrogenic and androgenic steroids can be synthesised in the brain and rapidly modulate synaptic transmission and plasticity through direct interaction with membrane receptors for estrogens (ERs) and androgens (ARs). We used whole cell patch clamp recordings in brainstem slices of male rats to explore the influence of ER and AR activation and local synthesis of 17β-estradiol (E2) and 5α-dihydrotestosterone (DHT) on the long-term synaptic changes induced in the neurons of the medial vestibular nucleus (MVN). Long-term depression (LTD) and long-term potentiation (LTP) caused by different patterns of high frequency stimulation (HFS) of the primary vestibular afferents were assayed under the blockade of ARs and ERs or in the presence of inhibitors for enzymes synthesizing DHT (5α-reductase) and E2 (P450-aromatase) from testosterone (T). We found that LTD is mediated by interaction of locally produced androgens with ARs and LTP by interaction of locally synthesized E2 with ERs. In fact, the AR block with flutamide prevented LTD while did not affect LTP, and the blockade of ERs with ICI 182,780 abolished LTP without influencing LTD. Moreover, the block of P450-aromatase with letrozole not only prevented the LTP induction, but inverted LTP into LTD. This LTD is likely due to the local activation of androgens, since it was abolished under blockade of ARs. Conversely, LTD was still induced in the presence of finasteride the inhibitor of 5α-reductase demonstrating that T is able to activate ARs and induce LTD even when DHT is not synthesized. This study demonstrates a key and opposite role of sex neurosteroids in the long-term synaptic changes of the MVN with a specific role of T-DHT for LTD and of E2 for LTP. Moreover, it suggests that different stimulation patterns can lead to LTD or LTP by specifically activating the enzymes involved in the synthesis of androgenic or estrogenic neurosteroids. PMID:24265837

Synaptic long-term potentiation and depression in the rat medial vestibular nuclei depend on neural activation of estrogenic and androgenic signals.

PubMed

Scarduzio, Mariangela; Panichi, Roberto; Pettorossi, Vito Enrico; Grassi, Silvarosa

2013-01-01

Estrogenic and androgenic steroids can be synthesised in the brain and rapidly modulate synaptic transmission and plasticity through direct interaction with membrane receptors for estrogens (ERs) and androgens (ARs). We used whole cell patch clamp recordings in brainstem slices of male rats to explore the influence of ER and AR activation and local synthesis of 17β-estradiol (E2) and 5α-dihydrotestosterone (DHT) on the long-term synaptic changes induced in the neurons of the medial vestibular nucleus (MVN). Long-term depression (LTD) and long-term potentiation (LTP) caused by different patterns of high frequency stimulation (HFS) of the primary vestibular afferents were assayed under the blockade of ARs and ERs or in the presence of inhibitors for enzymes synthesizing DHT (5α-reductase) and E2 (P450-aromatase) from testosterone (T). We found that LTD is mediated by interaction of locally produced androgens with ARs and LTP by interaction of locally synthesized E2 with ERs. In fact, the AR block with flutamide prevented LTD while did not affect LTP, and the blockade of ERs with ICI 182,780 abolished LTP without influencing LTD. Moreover, the block of P450-aromatase with letrozole not only prevented the LTP induction, but inverted LTP into LTD. This LTD is likely due to the local activation of androgens, since it was abolished under blockade of ARs. Conversely, LTD was still induced in the presence of finasteride the inhibitor of 5α-reductase demonstrating that T is able to activate ARs and induce LTD even when DHT is not synthesized. This study demonstrates a key and opposite role of sex neurosteroids in the long-term synaptic changes of the MVN with a specific role of T-DHT for LTD and of E2 for LTP. Moreover, it suggests that different stimulation patterns can lead to LTD or LTP by specifically activating the enzymes involved in the synthesis of androgenic or estrogenic neurosteroids.

Embolization of renal angiomyolipomas: short-term and long-term outcomes, complications, and tumor shrinkage.

PubMed

Lee, Shen-Yang; Hsu, Hsiang-Hao; Chen, Yung-Chang; Huang, Chen-Chih; Wong, Yon-Cheong; Wang, Li-Jen; Chuang, Cheng-Keng; Yang, Chih-Wei

2009-11-01

This study retrospectively evaluated outcomes, complications, and tumor shrinkage in renal angiomyolipomas after transcatheter arterial embolization (TAE). All renal angiomyolipoma patients who underwent TAE between August 2000 and December 2008 and had short-term (long-term (>6 months) follow-up images were evaluated. Complications and tumor relapse after TAE were reviewed. The sizes of embolized tumors were measured to calculate size reductions and reduction rates after TAE. Differences in tumor size, size reduction, and reduction rate between different time points (pre-TAE, short-term follow-up, and long-term follow-up) and groups (completely and incompletely embolized) were determined. Eleven renal angiomyolipoma patients who had undergone TAE were included. Seven (63.6%) patients had postembolization syndrome and one had abscess formation following TAE. Two patients had a tumor relapse (18.2%). The mean tumor size was 8.57+/-2.66 cm on pre-TAE images. The mean size reduction was 3.1 cm (33.3%) and 3.8 cm (43.0%) at short-term and long-term follow-up. Tumor sizes differed significantly between pre-TAE and short-term (p=0.004) or long-term images (p=0.022) but not between short-term and long-term images (p=0.059). Results stratified by the completeness of embolization indicate that only the short-term size reduction rate differed significantly (p=0.025), while the long-term reduction rate and short- and long-term follow-up tumor size and size reduction were comparable between the two groups. In conclusion, selective TAE is effective for tumor shrinkage in most renal angiomyolipomas, with acceptable complication and relapse rates. Tumor shrinkage occurring within 6 months after TAE may reflect the long-term effect of TAE.

Long-term care legislation: an issue of concern for nurse practitioners.

PubMed

Jennings, J P

1989-01-01

Comprehensive long-term care policy has many hurdles to overcome before it becomes a reality. The biggest hurdle is the price tag! Estimates range from $6 billion (Pepper's home-care bill) to $46 billion (Stark's long-term care coverage bill). Congressional insiders predict that federal long-term care coverage must contain "pay-as-you-go" financing to win congressional passage. The medicare catastrophic health care act is cited by many in the Congress as establishing the precedent for self-financing of new federal benefits. In a pay-as-you-go era in public spending, any new program can only come from trimming existing programs and shifting those funds to new programs or from generating new revenues. The latter could result from increased beneficiary cost-sharing, an increase in the medicare payroll tax, or by eliminating the $45,000 cap on income exposed to the current 1.45% medicare payroll tax. Federal proposals to date build on existing medicare and medicaid programs. In them, quality assurance measures have been strengthened, consumer input encouraged, and a new layer of bureaucracy established to screen potential clients and provide case-management services. The scope of services is broad in most of the current proposals, and reimbursement is provided for respite care to allow family care givers relief and assistance. Access to nurse practitioners' services is an important feature of Kennedy's Lifecare proposal and is the focus of lobbying efforts for all public and private proposals. It is time for nurse practitioners to become involved in long-term care legislation. This may be initiated by reviewing current proposals and long-term care packages offered by major insurance companies. Any future long-term care benefit should bear the imprint of the nurse practitioner's professional perspective and the profession's commitment to humane, caring health policy.

Integration of devices into long-term condition management: a synthesis of qualitative studies.

PubMed

Gately, Claire; Rogers, Anne; Kirk, Susan; McNally, Rosalind

2008-06-01

Understanding peoples' responses to and ability to incorporate technology for managing long-term conditions into their everyday lives is relevant for informing the development and implementation of new technologies as part of future long-term condition management in domestic environments. Future research and theory building can be facilitated by the synthesis of existing qualitative studies. A systematic search for qualitative studies of health technologies at home was undertaken on OVID CINAHL, OVID Medline and CSA databases for the period 1996-2006. Studies (n = 12) that met the inclusion criteria were synthesized and their analyses subjected to qualitative meta-synthesis. Analyses clustered into five themes: (1) managing multiple uncertainties; (2) the reconstruction of identity; (3) the struggle to remain autonomous while allowing dependence; (4) coming to terms with living a technology-assisted life; and (5) the usability of devices. These translated into a line of argument synthesis in which technology takes on the status of a personified ;other' around which a set of personal and relational attributions are subsequently constructed. These allow the extension of existing illness work to incorporate new technologies. Ambivalence about the value of technologies that are designed to assist with the management of a long-term condition reflects experiences of the disruptive effects of health technologies on personal identities and strategies of managing illness. At the same time, they are highly valued because they provided new opportunities to complete aspects of illness work that were previously impossible.