bluuebunny/crossref_metadata_2025_split huggingface dataset:
INCREASED INTRAOCULAR PRESSURE IS A RISK FACTOR FOR UNEXPLAINED VISUAL LOSS DURING SILICONE OIL ENDOTAMPONADE
Authors: Marti Marvin , Walton Richard , Böni Christian , Zweifel Sandrine A. , Stahel Marc , Barthelmes Daniel 
Published: January 2017

Purpose:
To identify the incidence rate and risk factors for unexplained visual loss associated with silicone oil endotamponade used during primary repair of macula-sparing rhegmatogenous retinal detachments.

Methods:
This retrospective cohort study included patients undergoing pars plana vitrectomy for primary surgical repair of macula-sparing rhegmatogenous retinal detachments in whom silicone oil endotamponade was used. The primary outcome measure was the incidence rate of unexplained visual loss and identification of risk factors associated with vision loss.

Results:
Of 1,218 eyes undergoing pars plana vitrectomy for primary retinal detachment repair, 44 eyes were included for analysis. In 9 eyes (20%), an unexplained vision loss occurred. Logistic regression identified increased intraocular pressure (IOP) (prospectively defined as IOP readings during silicone oil endotamponade ≥21 mmHg on two consecutive visits or ≥25 mmHg at any time during this period) as significant predictor (odds ratio = 4.9; P = 0.04) and a classification tree ranked IOP as the most important variable for vision loss. Incidence rate of vision loss in eyes experiencing IOP increase was 4.5 vision loss events per 1,000 days at risk compared with 1 event per 1,000 days in eyes without IOP increase, yielding an incidence rate ratio of 4.5 (95% confidence interval: 1.1–17.9; P = 0.02).

Conclusion:
Sufficient control of IOP during silicone oil endotamponade for primary retinal detachment repair is warranted to reduce the probability of vision loss.
MULTIMODAL IMAGING DURING THE EVOLUTION OF BLOOD–BRAIN BARRIER DISRUPTION MACULOPATHY
Authors: Pal Bikramjit P. , Palosaari Tapani , Kivelä Tero 
Published: January 2017

Purpose:
To highlight the course of blood–brain barrier disruption maculopathy in a patient with successfully managed relapsed central nervous system lymphoma.

Methods:
Case report with fundus autofluorescence and optical coherence tomography imaging, and literature review.

Results:
A 57-year-old patient diagnosed with central nervous system large B-cell lymphoma had a normal ophthalmic evaluation on his first visit. Subsequently, when his malignancy recurred locally, he was started on blood–brain barrier disruption therapy and intraarterial methotrexate. During the course of the therapy, he developed bilateral retinal pigment epithelial abnormalities located in the foveal and perifoveal zones. The changes were first mildly progressive and then marginally regressive in nature with minimal eventual loss of visual acuity to 20/32 and 20/25 in his right and left eye, respectively.

Conclusion:
Maculopathy is a known complication in patients with central nervous system malignancies undergoing blood–brain barrier disruption. A detailed clinical evaluation using fundus autofluorescence and high-definition optical coherence tomography are informative in managing such patients.
Divergent Influences of Cardiovascular Disease Risk Factor Domains on Cognition and Gray and White Matter Morphology
Authors: Gonzales Mitzi M. , Ajilore Olusola , Charlton Rebecca C. , Cohen Jamie , Yang Shaolin , Sieg Erica , Bhaumik Dulal K. , Kumar Anand , Lamar Melissa 
Published: January 2017

ABSTRACT

Objective
Hypertension, diabetes, dyslipidemia, and obesity are associated with preclinical alterations in cognition and brain structure; however, this often comes from studies of comprehensive risk scores or single isolated factors. We examined associations of empirically derived cardiovascular disease risk factor domains with cognition and brain structure.

Methods
A total of 124 adults (age, 59.8 [13.1] years; 41% African American; 50% women) underwent neuropsychological and cardiovascular assessments and structural magnetic resonance imaging. Principal component analysis of nine cardiovascular disease risk factors resulted in a four-component solution representing 1, cholesterol; 2, glucose dysregulation; 3, metabolic dysregulation; and 4, blood pressure. Separate linear regression models for learning, memory, executive functioning, and attention/information processing were performed, with all components entered at once, adjusting for age, sex, and education. MRI analyses included whole-brain cortical thickness and tract-based fractional anisotropy adjusted for age and sex.

Results
Higher blood pressure was associated with poorer learning (B = −0.19; p = .019), memory (B = −0.22; p = .005), and executive functioning performance (B = −0.14; p = .031), and lower cortical thickness within the right lateral occipital lobe. Elevated glucose dysregulation was associated with poorer attention/information processing performance (B = −0.21; p = .006) and lower fractional anisotropy in the right inferior and bilateral superior longitudinal fasciculi. Cholesterol was associated with higher cortical thickness within left caudal middle frontal cortex. Metabolic dysfunction was positively associated with right superior parietal lobe, left inferior parietal lobe, and left precuneus cortical thickness.

Conclusions
Cardiovascular domains were associated with distinct cognitive, gray, and white matter alterations and distinct age groups. Future longitudinal studies may assist in identifying vulnerability profiles that may be most important for individuals with multiple cardiovascular disease risk factors.
Functional consequences of pre- and postsynaptic expression of synaptic plasticity
Authors: Costa Rui Ponte , Mizusaki Beatriz E. P. , Sjöström P. Jesper , van Rossum Mark C. W. 
Published: January 2017

Growing experimental evidence shows that both homeostatic and Hebbian synaptic plasticity can be expressed presynaptically as well as postsynaptically. In this review, we start by discussing this evidence and methods used to determine expression loci. Next, we discuss the functional consequences of this diversity in pre- and postsynaptic expression of both homeostatic and Hebbian synaptic plasticity. In particular, we explore the functional consequences of a biologically tuned model of pre- and postsynaptically expressed spike-timing-dependent plasticity complemented with postsynaptic homeostatic control. The pre- and postsynaptic expression in this model predicts (i) more reliable receptive fields and sensory perception, (ii) rapid recovery of forgotten information (memory savings), and (iii) reduced response latencies, compared with a model with postsynaptic expression only. Finally, we discuss open questions that will require a considerable research effort to better elucidate how the specific locus of expression of homeostatic and Hebbian plasticity alters synaptic and network computations.
This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity’.
Integrating Hebbian and homeostatic plasticity: the current state of the field and future research directions
Authors: Keck Tara , Toyoizumi Taro , Chen Lu , Doiron Brent , Feldman Daniel E. , Fox Kevin , Gerstner Wulfram , Haydon Philip G. , Hübener Mark , Lee Hey-Kyoung , Lisman John E. , Rose Tobias , Sengpiel Frank , Stellwagen David , Stryker Michael P. , Turrigiano Gina G. , van Rossum Mark C. 
Published: January 2017

We summarize here the results presented and subsequent discussion from the meeting on Integrating Hebbian and Homeostatic Plasticity at the Royal Society in April 2016. We first outline the major themes and results presented at the meeting. We next provide a synopsis of the outstanding questions that emerged from the discussion at the end of the meeting and finally suggest potential directions of research that we believe are most promising to develop an understanding of how these two forms of plasticity interact to facilitate functional changes in the brain.
This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity’.
Enhancement of visual cortex plasticity by dark exposure
Authors: Erchova Irina , Vasalauskaite Asta , Longo Valentina , Sengpiel Frank 
Published: January 2017

Dark rearing is known to delay the time course of the critical period for ocular dominance plasticity in the visual cortex. Recent evidence suggests that a period of dark exposure (DE) may enhance or reinstate plasticity even after closure of the critical period, mediated through modification of the excitatory–inhibitory balance and/or removal of structural brakes on plasticity. Here, we investigated the effects of a week of DE on the recovery from a month of monocular deprivation (MD) in the primary visual cortex (V1) of juvenile mice. Optical imaging of intrinsic signals revealed that ocular dominance in V1 of mice that had received DE recovered slightly more quickly than of mice that had not, but the level of recovery after three weeks was similar in both groups. Two-photon calcium imaging showed no significant difference in the recovery of orientation selectivity of excitatory neurons between the two groups. Parvalbumin-positive (PV+) interneurons exhibited a smaller ocular dominance shift during MD but again no differences in subsequent recovery. The percentage of PV+ cells surrounded by perineuronal nets, a structural brake on plasticity, was lower in mice with than those without DE. Overall, DE causes a modest enhancement of mouse visual cortex plasticity.
This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity’.
Glutamatergic synapses are structurally and biochemically complex because of multiple plasticity processes: long-term potentiation, long-term depression, short-term potentiation and scaling
Authors: Lisman John 
Published: January 2017

Synapses are complex because they perform multiple functions, including at least six mechanistically different forms of plasticity. Here, I comment on recent developments regarding these processes. (i) Short-term potentiation (STP), a Hebbian process that requires small amounts of synaptic input, appears to make strong contributions to some forms of working memory. (ii) The rules for long-term potentiation (LTP) induction in CA3 have been clarified: induction does not depend obligatorily on backpropagating sodium spikes but, rather, on dendritic branch-specific
N
-methyl-
d
-aspartate (NMDA) spikes. (iii) Late LTP, a process that requires a dopamine signal (and is therefore neoHebbian), is mediated by trans-synaptic growth of the synapse, a growth that occurs about an hour after LTP induction. (iv) LTD processes are complex and include both homosynaptic and heterosynaptic forms. (v) Synaptic scaling produced by changes in activity levels are not primarily cell-autonomous, but rather depend on network activity. (vi) The evidence for distance-dependent scaling along the primary dendrite is firm, and a plausible structural-based mechanism is suggested.

Ideas about the mechanisms of synaptic function need to take into consideration newly emerging data about synaptic structure. Recent super-resolution studies indicate that glutamatergic synapses are modular (module size 70–80 nm), as predicted by theoretical work. Modules are trans-synaptic structures and have high concentrations of postsynaptic density-95 (PSD-95) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor. These modules function as quasi-independent loci of AMPA-mediated transmission and may be independently modifiable, suggesting a new understanding of quantal transmission.
This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity.’
Integrating Hebbian and homeostatic plasticity: introduction
Authors: Fox Kevin , Stryker Michael 
Published: January 2017

Hebbian plasticity is widely considered to be the mechanism by which information can be coded and retained in neurons in the brain. Homeostatic plasticity moves the neuron back towards its original state following a perturbation, including perturbations produced by Hebbian plasticity. How then does homeostatic plasticity avoid erasing the Hebbian coded information? To understand how plasticity works in the brain, and therefore to understand learning, memory, sensory adaptation, development and recovery from injury, requires development of a theory of plasticity that integrates both forms of plasticity into a whole. In April 2016, a group of computational and experimental neuroscientists met in London at a discussion meeting hosted by the Royal Society to identify the critical questions in the field and to frame the research agenda for the next steps. Here, we provide a brief introduction to the papers arising from the meeting and highlight some of the themes to have emerged from the discussions.
This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity’.
Effects of Altered Excitation-Inhibition Balance on Decision Making in a Cortical Circuit Model
Authors: Lam Norman H. , Borduqui Thiago , Hallak Jaime , Roque Antonio C. , Anticevic Alan , Krystal John H. , Wang Xiao-Jing , Murray John D. 
Published: January 2017

AbstractBackgroundDisruption of the synaptic balance between excitation and inhibition (E/I balance) in cortical circuits is a leading hypothesis for pathophysiologies of neuropsychiatric disorders, such as schizophrenia. However, it is poorly understood how synaptic E/I disruptions propagate upward to induce cognitive deficits, including impaired decision making (DM).MethodsWe investigated how E/I perturbations may impair temporal integration of evidence during perceptual DM in a biophysically-based model of association cortical microcircuits. Using multiple psychophysical task paradigms, we characterized effects of NMDA receptor hypofunction at two key synaptic sites: inhibitory interneurons (elevating E/I ratio, via disinhibition), versus excitatory pyramidal neurons (lowering E/I ratio).ResultsDisruption of E/I balance in either direction can similarly impair DM as assessed by psychometric performance, following inverted-U dependence. Nonetheless, these regimes make dissociable predictions for task paradigms that characterize the time course of evidence accumulation. Under elevated E/I ratio, DM is impulsive: evidence early in time is weighted much more than late evidence. In contrast, under lowered E/I ratio, DM is indecisive: evidence integration and winner-take-all competition between options are weakened. These effects are well captured by an extended drift-diffusion model with self-coupling.ConclusionsOur findings characterize critical roles of cortical E/I balance in cognitive functions, the utility of timing-sensitive psychophysical paradigms, and relationships between circuit and psychological models. The model makes specific predictions for behavior and neural activity that are testable in humans or animals under causal manipulations of E/I balance and in disease states.
Heritability of theSymbiodiniumcommunity in vertically- and horizontally-transmitting broadcast spawning corals
Authors: Quigley Kate , Willis Bette , Bay Line 
Published: January 2017

AbstractThe dinoflagellate-coral partnership influences the coral holobiont’s tolerance to thermal stress and bleaching. However, the comparative roles of host genetic versus environmental factors in determining the composition of this symbiosis are largely unknown. Here we quantify the heritability of the initialSymbiodiniumcommunities for two broadcast-spawning corals with different symbiont transmission modes:Acropora tenuishas environmental acquisition, whereasMontipora digitatahas maternal transmission. Using high throughput sequencing of the ITS-2 region to characterize communities in parents, juveniles and eggs, we describe previously undocumentedSymbiodiniumdiversity and dynamics in both corals. After one month of uptake in the field,Symbiodiniumcommunities associated withA. tenuisjuveniles were dominated by A3, C1, D1, A-type CCMP828, and D1a in proportional abundances conserved between experiments in two years.M. digitataeggs were predominantly characterized by C15, D1, and A3. In contrast to current paradigms, host genetic influences accounted for a surprising 29% of phenotypic variation inSymbiodiniumcommunities in the horizontally-transmittingA. tenuis, but only 62% in the vertically-transmittingM. digitata. Our results reveal hitherto unknown flexibility in the acquisition ofSymbiodiniumcommunities and substantial heritability in both species, providing material for selection to produce partnerships that are locally adapted to changing environmental conditions.
The RAG transposon is active through the deuterostome evolution and domesticated in jawed vertebrates
Authors: Morales Poole Jose Ricardo , Huang Sheng Feng , Xu Anlong , Bayet Justine , Pontarotti Pierre 
Published: January 2017

AbstractRAG1 and RAG2 are essential subunits of the V(D)J recombinase required for the generation of the variability of antibodies and T-cell receptors in jawed vertebrates. It was demonstrated that the amphioxus homologue of RAG1-RAG2 is encoded in an active transposon, belonging to the transposase DDE superfamily. The data provided supports to the possibility that the RAG transposon has been active through the deuterostome evolution and is still active in several lineages. The RAG transposon corresponds to several families present in deuterostomes. RAG1-RAG2 V(D)J recombinase evolved from one of them, partially due to the new ability of the transposon to interact with the cellular reparation machinery. Considering the fact that the RAG transposon survived millions of years in many different lineages, in multiple copies, and that DDE transposases evolved their association with proteins involved in repair mechanisms, we propose that the apparition of V(D)J recombination machinery could be a predictable genetic event.
Cone-like rhodopsin expressed in the all cone retina of the colubrid pine snake as a potential adaptation to diurnality
Authors: Bhattacharyya Nihar , Darren Benedict , Schott Ryan K. , Tropepe Vincent , Chang Belinda S.W. 
Published: January 2017

AbstractColubridae is the largest and most diverse family of snakes, with visual systems that reflect this diversity, encompassing a variety of retinal photoreceptor organizations. The transmutation theory proposed by Walls postulates that photoreceptors could evolutionarily transition between cell types in squamates, but few studies have tested this theory. Recently, evidence for transmutation and rod-like machinery in an all cone retina has been identified in a diurnal garter snake (Thamnophis), and it appears that the rhodopsin gene at least may be widespread among colubrid snakes. However, functional evidence supporting transmutation beyond the existence of the rhodopsin gene remains rare. We examined the all cone retina of another diurnal colubrid,Pituophis melanoleucus, distantly related toThamnophis. We found thatP. melanoleucusexpresses two cone opsins (SWS1, LWS) and rhodopsin (RH1) within the eye. Immunohistochemistry localized rhodopsin to the outer segment of photoreceptors in the all-cone retina of the snake and all opsin genes produced functional visual pigments when expressedin vitro. Consistent with other studies, we found thatP. melanoleucusrhodopsin is extremely blue-shifted. Surprisingly,P. melanoleucusrhodopsin reacted with hydroxylamine, a typical cone opsin characteristic. These results support the idea that the rhodopsin-containing photoreceptors ofP. melanoleucusare the products of evolutionary transmutation from rod ancestors, and suggests that this phenomenon may be widespread in colubrid snakes. We hypothesize that transmutation may be an adaptation for diurnal, brighter-light vision, which could result in increased spectral sensitivity and chromatic discrimination with the potential for colour vision.Summary StatementThe all cone retina of the colubrid snake,Pituophis melanoleucuscontains a blue-shifted rhodopsin with cone opsin-like properties, which may have been adaptive in diurnal snakes.
Governance structures, voluntary disclosures and public accountability
Authors: Ntim Collins G. , Soobaroyen Teerooven , Broad Martin J. 
Published: January 2017

PurposeThe purpose of this paper is to investigate the extent of voluntary disclosures in UK higher education institutions’ (HEIs) annual reports and examine whether internal governance structures influence disclosure in the period following major reform and funding constraints.Design/methodology/approachThe authors adopt a modified version of Coy and Dixon’s (2004) public accountability index, referred to in this paper as a public accountability and transparency index (PATI), to measure the extent of voluntary disclosures in 130 UK HEIs’ annual reports. Informed by a multi-theoretical framework drawn from public accountability, legitimacy, resource dependence and stakeholder perspectives, the authors propose that the characteristics of governing and executive structures in UK universities influence the extent of their voluntary disclosures.FindingsThe authors find a large degree of variability in the level of voluntary disclosures by universities and an overall relatively low level of PATI (44 per cent), particularly with regards to the disclosure of teaching/research outcomes. The authors also find that audit committee quality, governing board diversity, governor independence and the presence of a governance committee are associated with the level of disclosure. Finally, the authors find that the interaction between executive team characteristics and governance variables enhances the level of voluntary disclosures, thereby providing support for the continued relevance of a “shared” leadership in the HEIs’ sector towards enhancing accountability and transparency in HEIs.Research limitations/implicationsIn spite of significant funding cuts, regulatory reforms and competitive challenges, the level of voluntary disclosure by UK HEIs remains low. Whilst the role of selected governance mechanisms and “shared leadership” in improving disclosure, is asserted, the varying level and selective basis of the disclosures across the surveyed HEIs suggest that the public accountability motive is weaker relative to the other motives underpinned by stakeholder, legitimacy and resource dependence perspectives.Originality/valueThis is the first study which explores the association between HEI governance structures, managerial characteristics and the level of disclosure in UK HEIs.