Ετικέτες

Τρίτη 12 Ιουνίου 2018

Scholar : ΠΡΟΣΩΠΙΚΟ ΝΕΥΡΟ - νέα αποτελέσματα

[PDF] Κρανιοεγκεφαλικές κακώσεις, αξιολόγηση γνωστικών λειτουργιών

Σ Νικολάου, Δ Αλεξιάδη, ΚΧ Ευαγγελίδη, Μ Κάζογλου - 2018
… Από και προς τον νωτιαίο μυελό υπάρχουν προβολές του περιφερικού
νευρικού συστήματος, με τη μορφή του νωτιαίων νεύρων (μερικές φορές
τμηματικά νεύρα) (Moore, Dalley & Agur, 2010) … ιερού οστού (Moore, Dalley …
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Scholar : ΟΓΚΟΛΟΓΙΑ - νέα αποτελέσματα

[PDF] Η χρήση του επιχειρηματικού σχεδίου (business plan) στο χώρο της υγείας. Ίδρυση ιδιωτικής κλινικής

ΓΙ Βακής - 2018
… Το τμήμα είναι στελεχωμένο από γενικούς χειρουργούς με εξειδίκευση στο
μαστό και στην ογκολογία του μαστού ,έτοιμοι να αντιμετωπίσουν κάθε είδους
διάγνωση και επέμβαση από την απλή ογκεκτομή μιας καλοήθειας …
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Scholar : ΡΙΝΙΚΟ ΔΙΑΦΡΑΓΜΑ - νέα αποτελέσματα

[PDF] Κρανιοεγκεφαλικές κακώσεις, αξιολόγηση γνωστικών λειτουργιών

Σ Νικολάου, Δ Αλεξιάδη, ΚΧ Ευαγγελίδη, Μ Κάζογλου - 2018
Page 1. Α.ΤΕΙ ΗΠΕΙΡΟΥ ΤΜΗΜΑ ΛΟΓΟΘΕΡΑΠΕΙΑΣ ΠΤΥΧΙΑΚΗ ΕΡΓΑΣΙΑ
ΚΡΑΝΙΟΕΓΚΕΦΑΛΙΚΕΣ ΚΑΚΩΣΕΙΣ ΑΞΙΟΛΟΓΗΣΗ ΓΝΩΣΤΙΚΩΝ
ΛΕΙΤΟΥΡΓΙΩΝ ΝΙΚΟΛΑΟΥ ΣΟΦΙΑ Α.Μ : 15730 ΑΛΕΞΙΑΔΗ ΔΗΜΗΤΡΑ …
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Scholar : Πλαστική Χειρουργική - νέα αποτελέσματα

[PDF] Η χρήση του επιχειρηματικού σχεδίου (business plan) στο χώρο της υγείας. Ίδρυση ιδιωτικής κλινικής

ΓΙ Βακής - 2018
… Η πλαστική χειρουργική, τόσο στο επανορθωτικό κομμάτι αποκατάστασης
μετά από κακοήθεια … Οι επεμβάσεις επανορθωτικής πλαστικής χειρουργικής
οι οποίες έχουν προέλθει μετά από … ΕΠΕΜΒΑΣΗ ΜΑΣΤΕΚΤΟΜΗΣ ΚΑΙ …
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Scholar : Θυρεοειδής - νέα αποτελέσματ

[PDF] Η χρήση του επιχειρηματικού σχεδίου (business plan) στο χώρο της υγείας. Ίδρυση ιδιωτικής κλινικής

ΓΙ Βακής - 2018
Page 1. ΠΡΟΓΡΑΜΜΑ ΜΕΤΑΠΤΥΧΙΑΚΩΝ ΣΠΟΥΔΩΝ «ΟΙΚΟΝΟΜΙΚΑ και ΔΙΟΙΚΗΣΗ της
ΥΓΕΙΑΣ» Η ΧΡΗΣΗ ΤΟΥ ΕΠΙΧΕΙΡΗΜΑΤΙΚΟΥ ΣΧΕΔΙΟΥ (BUSINESS PLAN) ΣΤΟ ΧΩΡΟ
ΤΗΣ ΥΓΕΙΑΣ . ΊΔΡΥΣΗ ΙΔΙΩΤΙΚΗΣ ΚΛΙΝΙΚΗΣ ΒΑΚΗΣ Ι. ΓΕΩΡΓΙΟΣ …
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Scholar : ΧΗΜΕΙΟΘΕΡΑΠΕΙΑ - νέα αποτελέ

[PDF] Η χρήση του επιχειρηματικού σχεδίου (business plan) στο χώρο της υγείας. Ίδρυση ιδιωτικής κλινικής

ΓΙ Βακής - 2018
… ΟΓΚΟΛΟΓΙΚΟ ΤΜΗΜΑ Το τμήμα είναι στελεχωμένο από εξειδικευμένους παθολόγους
ογκολόγους για τον καρκίνου του μαστού και είναι έτοιμοι να παρέχουν κάθε είδους
θεραπεία (χημειοθεραπεία , ορμονοθεραπεία ) για να τον αντιμετωπίσουν πλήρως …
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Οι κακοήθεις νεοπλασίες στην παιδική ηλικία, ο ρόλος του νοσηλευτή και νέα δεδομένα

Γ Κωνσταντοπούλου - 2018
… με νέες εφαρμογές. Μελέτες γίνονται με στόχο την αντιμετώπιση των παρενεργειών
που έχει η χημειοθεραπεία και η ακτινοθεραπεία στις νοητικές λειτουργίες των παιδιών
που επιζούν από τον καρκίνο. Συμπεράσματα Ο αγώνας …
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Scholar : ΛΑΡΥΓΓΑΣ - νέα αποτελέσματα

[PDF] Κρανιοεγκεφαλικές κακώσεις, αξιολόγηση γνωστικών λειτουργιών

Σ Νικολάου, Δ Αλεξιάδη, ΚΧ Ευαγγελίδη, Μ Κάζογλου - 2018
Page 1. Α.ΤΕΙ ΗΠΕΙΡΟΥ ΤΜΗΜΑ ΛΟΓΟΘΕΡΑΠΕΙΑΣ ΠΤΥΧΙΑΚΗ ΕΡΓΑΣΙΑ
ΚΡΑΝΙΟΕΓΚΕΦΑΛΙΚΕΣ ΚΑΚΩΣΕΙΣ ΑΞΙΟΛΟΓΗΣΗ ΓΝΩΣΤΙΚΩΝ
ΛΕΙΤΟΥΡΓΙΩΝ ΝΙΚΟΛΑΟΥ ΣΟΦΙΑ Α.Μ : 15730 ΑΛΕΞΙΑΔΗ ΔΗΜΗΤΡΑ …
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Αυτή η ειδοποίηση αποστέλλεται από τον Μελετητή Google. Ο Μελετητής Google είναι μια υπηρεσία που παρέχεται από την Google.



Scholar : ΑΚΟΗ - νέα αποτελέσματα

[PDF] Κρανιοεγκεφαλικές κακώσεις, αξιολόγηση γνωστικών λειτουργιών

Σ Νικολάου, Δ Αλεξιάδη, ΚΧ Ευαγγελίδη, Μ Κάζογλου - 2018
Page 1. Α.ΤΕΙ ΗΠΕΙΡΟΥ ΤΜΗΜΑ ΛΟΓΟΘΕΡΑΠΕΙΑΣ ΠΤΥΧΙΑΚΗ ΕΡΓΑΣΙΑ
ΚΡΑΝΙΟΕΓΚΕΦΑΛΙΚΕΣ ΚΑΚΩΣΕΙΣ ΑΞΙΟΛΟΓΗΣΗ ΓΝΩΣΤΙΚΩΝ
ΛΕΙΤΟΥΡΓΙΩΝ ΝΙΚΟΛΑΟΥ ΣΟΦΙΑ Α.Μ : 15730 ΑΛΕΞΙΑΔΗ ΔΗΜΗΤΡΑ …
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Αυτή η ειδοποίηση αποστέλλεται από τον Μελετητή Google. Ο Μελετητής Google είναι μια υπηρεσία που παρέχεται από την Google.



Model for Hormonal Emergency Contraception (HEC) in Cycling and Mated Guinea Pigs – Studies with the Progesterone Receptor Modulators (PRM) Ulipristal Acetate (UPA / CDB2914) and EC317

Publication date: Available online 11 June 2018
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): W Elger, B Schneider, Z Killeen, K Jewgenow, M Dehnhard, M Friedrich, B Santhamma, R Wedemeyer, K Nickisch
A guinea pig model for new HEC methods is proposed. Two targets for HEC (Hormonal Emergency Contraception), ovulation and conception (post-mating study), were investigated using adjusted PRM treatments: (a) Ovulation inhibition study: Injections on cycle days 10 – 17, study of ovarian histology on day 18; (b) post-mating study: Injections on cycle days 1 and 2; rate of pregnant females was recorded at autopsy on day 18. P plasma levels permitted assessment of effects on ovulation in non-conceiving animals. Results: (a) All controls had recently ovulated. Statistically significant anti-ovulatory effects (p < 0.05, Fisher's Exact Test) were seen at 10 mg UPA (ulipristal acetate, CDB2914) and ≥ 0.3 mg EC317; 100 % inhibition was found for EC317 at 10, 3, and 1 mg/day. No dosage of UPA was 100 % effective. (b) In post-mating studies, 16 of 30 controls were pregnant. Both PRMs (progesterone receptor modulator) exerted inhibitory effects on conception, none on imminent ovulation; 1 of 10 animals had living conceptuses after 10 mg UPA, none following 10 and 1 mg EC317/day, respectively. At pairwise comparison with controls, 10 mg was the lowest effective dosage for UPA (p < 0.05), and 1 mg for EC317 (p < 0.01). P plasma levels: Significantly lower P (p < 0.05) in subsequently pregnant vs non-pregnant controls was found on cycle day 3 or 4; this difference disappeared on day 8 or 9. This stage thus appears vulnerable to hormonal constellations and possibly PRM effects. HEC model: Effects on ovulation and conception were seen at the same dose levels of both PRM. Superior and more consistent effects of EC317 vs UPA (factor ≥10) suggest higher efficacy using EC317 for HEC.

Graphical abstract

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Fluoxetine and stress inversely modify lateral septal nucleus-mpfc neuronal responsivity

Publication date: 1 October 2018
Source:Behavioural Brain Research, Volume 351
Author(s): Carlos M. Contreras, Ana G. Gutiérrez-García, José A. Sánchez-Salcedo
Several clinically effective antidepressants increase the neuronal firing rate in the lateral septal nucleus (LSN), a forebrain structure that is anatomically related to medial prefrontal cortex (mPFC) regions. mPFC function is related to depression and the regulation of fear. However, unknown is whether antidepressant treatment or chronic stress modifies the responsivity of neuronal LSN-mPFC connections. We performed single-unit extracellular recordings in the anterior cingulate cortex (ACC) and prelimbic (PL) and infralimbic (IL) regions of the mPFC during stimulation of the LSN in anesthetized male Wistar rats that received fluoxetine (1 mg/kg, 21 days) or were subjected to chronic mild stress (5 weeks). The results were compared with a control group (saline treatment, devoid of behavioral manipulations). Stimulation of the LSN produced an initial excitatory paucisynaptic response, followed by an afterdischarge, characterized by an increase in the neuronal firing rate. Opposite changes were induced by fluoxetine treatment and chronic stress exposure. Peristimulus histograms and unit-activity ratio analyses indicated that LSN-mPFC responsivity differed between fluoxetine treatment and chronic stress exposure. Fluoxetine reduced neuronal responsivity in the LSN-PL and LSN-IL, and stress increased neuronal responsivity in the same regions. In both cases, the changes were more pronounced in the IL region. The lower responsivity of LSN-PL and LSN-IL connections that was produced by fluoxetine may reflect a higher threshold for fear, and lower responsivity of this connection may be related to states of fear. The LSN and mPFC comprise a portion of a limbic-cortical circuit where neuronal responses depend on specific conditions.



https://ift.tt/2JLUJew

Lipopolysaccharide (LPS) induced sickness in adolescent female rats alters the acute-phase response and lithium chloride (LiCl)- induced impairment of conditioned place avoidance/aversion learning, following a homotypic LPS challenge in adulthood

Publication date: 1 October 2018
Source:Behavioural Brain Research, Volume 351
Author(s): Caylen J. Cloutier, Martin Kavaliers, Klaus-Peter Ossenkopp
The multi-variable locomotor activity effects of LiCl treatment in female rats were examined in a conditioned place avoidance/aversion (CPA) paradigm. In addition, the sickness effects of an LPS injection (200 μg/kg), given during adolescents, on CPA learning in adulthood were examined, as were the effects of a homotypic LPS injection (200 μg/kg) just prior to CPA acquisition trials. Female rats were injected with LPS or saline during adolescents (6 weeks of age) and later pretreated with LPS again or saline in an automated two-chamber CPA paradigm with LiCl (95 mg/kg) treatments as the aversive toxin. Results showed that, while adolescent LPS treatment had no long-term effect on the establishment of CPA, it did interfere with the ability of a second LPS challenge in adulthood to impair CPA learning, an effect obtained in subjects pretreated with LPS in the CPA procedure in adulthood only. The results of this study demonstrate the importance of considering the adolescent stage of development when evaluating the effects of environmental challenges on adult behavior.



https://ift.tt/2LFQ1MD

El Condor mine: Prehispanic production and consumption of hematite pigments in the Atacama Desert, northern Chile

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Publication date: Available online 11 June 2018
Source:Journal of Anthropological Archaeology
Author(s): Marcela Sepúlveda, Francisco Gallardo, Benjamín Ballester, Gloria Cabello, Estefanía Vidal
The mineral richness of the Atacama Desert permitted the development of a diverse array of mining activities, including the production of metals, lapidary, and pigments, which developed into significant sociocultural practices for desert dwellers throughout the occupation of the region. El Cóndor mine is an important hematite source located in the middle section of the Loa River, exploited from the Formative Period (ca. AD 300) until Inca times (ca. AD 1500). In contrast to other mining sites of Atacama region, the El Condor mine complex contains specialized infrastructure where different kinds of activities were carried out: extraction pits, processing areas with multiple anvils and grinding tools, and semicircular structures used for domestic activities. Pigment production was initially developed as a small-scale craft that intensified during later periods (ca. AD 1200). It was most extensive following the Inca expansion (ca. AD 1400), as evidenced by wider networks of distribution and consumption, as well as infrastructural changes. El Cóndor mine constitutes a notable example of a large-scale hematite operation that articulated important networks of exchange, and as such provides a case study for evaluating the organization of mining activities during late periods of the pre-Hispanic sequence in the Atacama Desert. We then emphasize that the circulation of pigments constitutes an important social practice and a salient economic activity, fulfilling a political role through the production and reproduction of social relations between different cultural entities that could be compared to similar cases from other regions in the world.



https://ift.tt/2LH8sAq

Generation and characterisation of gallium titanate surfaces through hydrothermal ion-exchange processes

Publication date: 5 October 2018
Source:Materials & Design, Volume 155
Author(s): Matthew D. Wadge, Bryan W. Stuart, Kathryn G. Thomas, David M. Grant
Infection negation and biofilm prevention are necessary developments needed for implant materials. Furthermore, an increase in publications regarding gallium (Ga) as an antimicrobial ion has resulted in bacterial-inhibitory surfaces incorporating gallium as opposed to silver (Ag). The authors present the production of novel gallium titanate surfaces through hydrothermal ion-exchange reactions. Commercially-pure Ti (S0: Cp-Ti) was initially suspended in NaOH solutions to obtain sodium titanate (S1: Na2TiO3) layers ca. 0.5–1 μm in depth (2.4 at.% Na). Subsequent suspension in Ga(NO3)3 (S2: Ga2(TiO3)3), and post-heat-treatment at 700 °C (S3: Ga2(TiO3)3-HT), generated gallium titanate layers (9.4 and 4.1 at.% Ga, respectively). For the first time, RHEED analysis of gallium titanate layers was conducted and demonstrated titanate formation. Degradation studies in DMEM showed S2: Ga2(TiO3)3 released more Ga compared to S3: Ga2(TiO3)3-HT (2.76 vs. 0.68 ppm) over 168 h. Furthermore, deposition of Ca/P in a Ca:P ratio of 1.71 and 1.34, on S2: Ga2(TiO3)3 and S3: Ga2(TiO3)3-HT, respectively, over 168 h was seen. However, the study failed to replicate the antimicrobial effect presented by Yamaguchi who utilised A. baumannii, compared to S. aureus used presently. The authors feel a full antimicrobial study is required to assess gallium titanate as a candidate antimicrobial surface.

Graphical abstract

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Differentiation of Different Nonmelanoma Skin Cancer Types Using OCT

Background: Early detection of various types of nonmelanoma skin cancer has been a challenge in dermatology. Noninvasive examination procedures such as optical coherence tomography (OCT) play an increasingly important role, besides the established gold standard of histological tissue sample analysis. OCT is a noninvasive, cross-sectional, real-time technique that allows conclusions to be drawn with regard to the presence of pathologies. Objective: The objective of this study was to investigate whether it is possible to distinguish between different types of nonmelanoma skin cancer using OCT or not. Methods: A study population of a total of 25 cases, comprising 5 cases, each, of 5 tumor entities (i.e., basal cell carcinoma, superficial basal cell carcinoma, actinic keratosis, squamous cell carcinoma, and Bowen disease) was examined. Relevant lesions were scanned both centrally and peripherally in the multislice mode. All OCT images were blinded, randomized, analyzed, and evaluated by 2 clinicians experienced in OCT. Results: This study demonstrated that it is possible to determine correlations between various types of tumors and recurring tumor characteristics. Conclusion: This study showed that it is possible to distinguish between the different nonmelanoma skin cancers by using OCT, but further prospective studies have to be conducted to validate the sensitivity and specificity of the criteria.
Skin Pharmacol Physiol 2018;31:238–245

https://ift.tt/2l5zXs0

Pre- and post-surgery MRSI predictive value in adult oligodendroglioma prognosis

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Publication date: Available online 11 June 2018
Source:Magnetic Resonance Imaging
Author(s): Caroline Bund, François Lefebvre, Roland Schott, Marie-Pierre Chenard, Benoît Lhermitte, Hélène Cebula, Stéphane Kremer, François Proust, Izzie-Jacques Namer
PurposeThe aim of this study was to study the relationship between MRSI, before and after surgery, and patient survival. The accuracy of pre-operative MRSI in differentiating low- from high-grade oligodendrogliomas (ODGs) was also studied.MethodsTwo hundred patients with ODG were retrospectively included in this study between 2000 and 2016. All patients underwent MRSI before any treatment or biopsy and/or after surgery for an intra-axial brain tumour. The R software was used for statistical data analysis. p < 0.05 was considered statistically significant. Kaplan-Meier curves were calculated for patients with low-grade ODG and high-grade ODG pre- and post-operatively, to study survival (overall survival, OS). The best threshold of each MRSI metabolite ratio was obtained using receiver operating characteristic curves (ROCs).ResultsOne hundred patients underwent pre-operative MRSI and 170 post-operative MRSI. N-acetylaspartate (NAA), lactate (Lac), choline (Cho) and creatine (Cr) were measured. Kapan-Meier curves showed that survival was poorer for a nCho/Cr > 3.02 in the pre-operative and nCho/Cr > 2.04, Lac/Cr > 0.743 and nCho/NAA > 3.63 in the post-operative period. Post-operative MRSI predicts survival better than pre-operative MRSI. nCho/Cr and Lac/Cr distinguished low- from high-grade ODG with a good positive predictive value.ConclusionMRSI is associated with survival. It is a non-invasive tool which completes histopathology and can predict patients' prognosis, thus improving patient management.



https://ift.tt/2HGmC2r

Neurons That Update Representations of the Future

Publication date: Available online 11 June 2018
Source:Trends in Cognitive Sciences
Author(s): Peggy Seriès
A recent article shows that the brain automatically estimates the probabilities of possible future actions before it has even received all the information necessary to decide what to do next.



https://ift.tt/2t1BXp1

With Great Data Comes Great (Theoretical) Opportunity

Publication date: Available online 11 June 2018
Source:Trends in Cognitive Sciences
Author(s): Michael C. Frank
Is there a 'critical period' for language? Using a viral online grammar test, Hartshorne, Tenenbaum, and Pinker (2018) collected a new massive dataset on the relationship between age and language learning. Their data highlight both the importance – and the challenges – of creating quantitative theories linking 'big data' to cognitive models.



https://ift.tt/2l3RLUw

Cell volume changes as revealed by fluorescence microscopy: Global vs local approaches

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Publication date: 1 August 2018
Source:Journal of Neuroscience Methods, Volume 306
Author(s): Thuraya Awadová, Helena Pivoňková, Zuzana Heřmanová, Denisa Kirdajová, Miroslava Anděrová, Jan Malínský
BackgroundSeveral techniques for cell volume measurement using fluorescence microscopy have been established to date. In this study, we compare the performance of three different approaches which allow for estimations of the cell volume changes in biological samples containing individual fluorescently labeled cells either in culture or in the tissue context. The specific requirements, limitations and advantages of individual approaches are discussed.New MethodGlobal morphometric data are quantitatively compared with local information about the overall cell volume, represented by the concentration of a mobile fluorophore accumulated within the monitored cell.ResultsVolume changes induced by variations in the extracellular osmolarity in murine fibroblasts and astrocytes either in the culture or in the acute brain slices were registered by the three- and two-dimensional morphometries and by local fluorescence intensity measurements. The performance of the latter approach was verified using FRAP assessment of the fluorophore mobility. Significantly lower amplitudes of the cortical astrocytes swelling were detected by three-dimensional morphometry, when compared to the other two approaches. Consequently, it failed to detect temperature-induced cell volume changes.Comparison with Existing Method(s)The three most popular methods of cell volume measurement are compared to each other in this study.ConclusionsWe show that the effectivity of global morphometry-based volumetric approaches drops with the increasing cell shape complexity or in the tissue context. In contrast to this, the performance of local fluorescence intensity monitoring, which is also fully capable of reflecting the instant cell volume variations remains stable, independent of the system used and application.



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An optimized method for enrichment of whole brain-derived extracellular vesicles reveals insight into neurodegenerative processes in a mouse model of Alzheimer’s disease

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Publication date: Available online 9 June 2018
Source:Journal of Neuroscience Methods
Author(s): Stephanie N. Hurwitz, Li Sun, Kalonji Y. Cole, Charles R. Ford, James M. Olcese, David G. Meckes
BackgroundAlzheimer's disease (AD) is the major cause of dementia that has increased dramatically in prevalence over the past several decades. Yet many questions still surround the etiology of AD. Recently, extracellular vesicles (EVs) that transport protein, lipid, and nucleic acids from cell to cell have been implicated in the clearance and propagation of misfolded proteins. Investigation of EVs in AD progression, and their potential diagnostic utility may contribute to understanding and treating AD. However, the challenges of isolating brain-derived EVs have in part hindered these studies.New methodHere, we provide an optimized method for the enrichment of brain-derived EVs by iodixanol floatation density gradient for mass spectrometry analysis.ResultsWe demonstrate the isolation of these vesicles and the enrichment of EV proteins compared to sedimentation gradient isolation of vesicles. Moreover, comparative proteomic analysis of brain-derived EVs from healthy and AD mouse brains revealed differences in vesicular content including proteins involved in aging, immune response, and oxidation-reduction maintenance. These changes provide insight into AD-associated neurodegeneration and potential biomarkers of AD.Comparison with existing methods: Recent techniques have used sedimentation sucrose gradients to isolate EVs from brain tissue. However, here we demonstrate the advantages of floatation iodixanol density gradient isolation of small EVs, and provide evidence of EV enrichment by electron microscopy, immunoblot analysis, and quantitative mass spectrometry.ConclusionsTogether these findings offer a rigorous technique for enriching whole tissue-derived EVs for downstream analyses, and application of this approach to uncovering molecular changes in AD progression and other neurological conditions.



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Insulin and heparin-binding epidermal growth factor-like growth factor synergistically promote astrocyte survival and proliferation in serum-free medium

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Publication date: Available online 8 June 2018
Source:Journal of Neuroscience Methods
Author(s): Mei Jia, Zhongfang Shi, Xu Yan, Lixin Xu, Liping Dong, Jiaxin Li, Yujiao Wang, Shaohua Yang, Fang Yuan
BackgroundIn vitro systems allowing maintenance and experimentation on primary astrocyte cultures have been used for decades. Astrocyte cultures are most maintained in serum-containing medium which has been found to alter the morphology and gene profiles of astrocytes.New methodHere, we reported a new serum-free medium for astrocyte culture, which consisted of DMEM and NB media supplemented with insulin and heparin-binding epidermal growth factor-like growth factor (HB-EGF) (SF-I-H medium). Meanwhile FBS-containing (FBS) medium composed of DMEM medium containing 10% FBS were used for comparison study. Cerebral cortex was harvested from postnatal day 1 Wistar rats and brain cells were isolated and seeded to poly-L-lysine coated culture dishes after 15 min differential velocity adherence.ResultsCompared with FBS medium, astrocytes in SF-I-H medium are smaller and exhibited process bearing morphologies. MTT assays showed that cell density and proliferation rate were higher in SF-I-H medium than in FBS medium all the time, and flow cytometry analysis revealed that SF-I-H medium promoted cell mitosis in a manner comparable to FBS medium. Consistently, western blot analysis further revealed that insulin and HB-EGF synergistically activated the PI3K-AKT and MAPK-ERK1/2 signaling cascades as FBS.Comparison with existing method(s)Astrocytes cultured in SF-I-H medium grow faster than FBS medium.ConclusionTaken together, our results indicated that SF-I-H medium, in which cell morphology was similar with astrocytes in brain, was more effective for astrocyte survival and proliferation than FBS medium, providing a new cell model to study astrocyte functions without the interference of serum.



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Procholecystokinin Expression And Processing in Cardiac Myocytes

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Publication date: Available online 11 June 2018
Source:Peptides
Author(s): Jens P. Goetze, Jens F. Rehfeld
The mammalian heart is by now an established endocrine organ whose myocytes in a regulated manner release atrial and ventricular natriuretic peptides (ANP and BNP). But like other hormone-producing cells in classic endocrine organs, the cardiac myocytes also express genes of additional peptide hormones. One such hormone gene is that of the well-known pleiotropic gut-brain peptide system, cholecystokinin (CCK), which is expressed at mRNA and protein levels in both atrial and ventricular cardiac myocytes. The posttranslational processing of proCCK in the myocytes, however, deviates substantially from that of other CCK-producing cells. Hence, the predominant cardiac proCCK product is devoid of the N-terminal 1-24 fragment, and besides O-sulfated at three C-terminal tyrosyl residues (Y76, Y90, and Y92). Moreover, carboxyamidated CCK peptides are present only in very low trace amounts (≤0.1%) in comparison with the truncated and triple-sulfated proCCK fragment. The present review first summarizes present knowledge about the wide-spread expression of the CCK system in mammals, and then discusses the possible function and biomarker role of the specific cardiac proCCK variant. The review concludes that the many unsettled questions about the specific cardiac expression cascade as well as the functional and diagnostic roles of cardiac CCK are worth pursuing.



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Eccrine Porocarcinoma: New Insights and a Systematic Review of the Literature

BACKGROUND Eccrine porocarcinoma (EPC) is a rare cutaneous neoplasm with high potential for morbidity and mortality. Due to its rarity, there is a paucity of data profiling diagnosis, work-up, and management. OBJECTIVE To consolidate reported information on demographics, diagnostics, clinical behavior, treatment modalities, and patient outcomes in EPC to provide a reference tool to optimize diagnosis and management. METHODS A comprehensive PubMed search was performed from 1963 to November 2017 using PRISMA guidelines. This yielded 155 articles detailing 206 cases of porocarcinoma. RESULTS Eccrine porocarcinoma most often presents in elderly patients on the head and neck or lower limbs. Metastatic disease at presentation is not uncommon (22%). Primary tumor location is significantly correlated with presence of metastasis (p = .038). The most common treatment is excision followed by Mohs micrographic surgery (MMS), although the outcomes after MMS were superior to those after surgical excision. CONCLUSION This systematic review of individual patient data reveals that all patients should have a histological diagnosis with imaging considered for high-risk cases. Primary tumor location should also be considered in diagnostic and therapeutic decision-making. Although wide local excision (WLE) is currently the first-line treatment, MMS is becoming increasingly used, with evidence indicating improved outcomes as compared to those seen with WLE. Address correspondence and reprint requests to: Shauna Higgins, MD, Department of Dermatology, Keck Medicine of USC, Los Angeles, CA 90017, or e-mail: shaunahigginsmd@gmail.com The authors have indicated no significant interest with commercial supporters. © 2018 by the American Society for Dermatologic Surgery, Inc. Published by Wolters Kluwer Health, Inc. All rights reserved.

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Treatment of Cosmetic Tattoos: A Review and Case Analysis

BACKGROUND Cosmetic tattoos such as eyeliner, brow liner, and lip liner have become increasingly popular in the United States and throughout the world. For a variety of reasons, patients frequently regret their tattoos and request their removal; however, removal is often complicated by the aesthetically sensitive location of these specialized tattoos and the fact that they often contain white metallic compounds that darken on pigment-specific laser irradiation. OBJECTIVE To review the clinical use, effectiveness, and safety of an ablative laser technique for cosmetic tattoos. MATERIALS AND METHODS A thorough literature review pertaining to laser treatment of cosmetic tattoos and a discussion of illustrative patient cases showcasing the successful use of ablative carbon dioxide (CO2) laser to treat cosmetic tattoos is presented. RESULTS Cosmetic eyeliner and lip liner tattoos were significantly improved after CO2 laser vaporization. Side effects were limited to erythema, edema, and serosanguinous drainage. No infection, scarring, nor tattoo ink darkening was observed. CONCLUSION Because ablative lasers do not target specific tattoo inks, they do not pose a risk of paradoxical tattoo ink darkening and, thus, can be applied successfully in the treatment of iron oxide– or titanium dioxide–containing cosmetic tattoos. Address correspondence and reprint requests to: Tina S. Alster, MD, Washington Institute of Dermatologic Laser Surgery, 1430 K Street, NW Suite 200, Washington, DC 20005, or e-mail: talster@skinlaser.com The authors have indicated no significant interest with commercial supporters. © 2018 by the American Society for Dermatologic Surgery, Inc. Published by Wolters Kluwer Health, Inc. All rights reserved.

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Concentrated Growth Factor Enhanced Fat Graft Survival: A Comparative Study

BACKGROUND Concentrated growth factors (CGFs) belong to a new generation biomaterials that concentrate large number of growth factors and CD34+ stem cells in small volume of plasma. OBJECTIVE The purpose of this study was to evaluate the impact of the new technique, CGF, on fat graft survival, which compared with platelet-rich plasma (PRP) and platelet-rich fibrin (PRF). MATERIALS AND METHODS Nude mice received fat graft were divided into PRP group, PRF group, CGF group, and saline. The grafts were volumetrically and histologically evaluated at 4, 8, and 12 weeks after fat grafting. In vitro growth factor levels in PRP, PRF, and CGF were compared using enzyme-linked immunoassay method. Cell count and real-time polymerase chain reaction were used to evaluate the impact of CGF in medium on human adipose-derived stem cell (hADSC) proliferation and vascular differentiation, respectively. RESULTS Fat graft weight was significantly higher in the CGF group than those in the other groups, and histologic evaluation revealed greater vascularity, fewer cysts, and less fibrosis. Adding CGF to the medium maximally promoted hADSC proliferation and expressing vascular endothelial growth factor and PECAM-1. CONCLUSION In this preliminary study, CGF treatment improved the survival and quality of fat grafts. Address correspondence and reprint requests to: Hang Wang, MD, PhD, Department of Oral and Maxillofacial Surgery, West China School of Stomatology, Sichuan University, No. 14, third Section, Ren Min Nan Road, Chengdu 610041, P.R.China, or e-mail: dr.hangwang@gmail.com The authors have indicated no significant interest with commercial supporters. Y. Hu and Y. Jiang authors are contributed equally and should be considered as co-first authors. © 2018 by the American Society for Dermatologic Surgery, Inc. Published by Wolters Kluwer Health, Inc. All rights reserved.

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Durability, Behavior, and Tolerability of 5 Hyaluronidase Products

BACKGROUND Hyaluronic acid (HA) dermal fillers are commonly used in cosmetic dermatology. Due to differences in their physical characteristics, HA fillers demonstrate different sensitivity to degradation by hyaluronidase (Hase) because of HA concentration and differences in cross-linking. Similarly, there are differences in the activity of Hase products depending on source and concentration. OBJECTIVE The primary objective was to demonstrate the differences in potency and activity of 5 Hase products when used to degrade 5 different HA products using a human in vivo model. MATERIALS AND METHODS The study subject was a healthy, consenting adult woman scheduled to undergo abdominoplasty. Skin to be excised was injected with 0.1 to 0.2 mL of each filler (10 injections each) leaving a visible lump. Immediately afterward, the HA lumps were injected with 4 IU of each Hase product every 2 minutes until the HA lumps were no longer visible or palpable. This procedure was repeated after 30 days. Injected tissues were excised after abdominoplasty for histological analysis. RESULTS The 5 Hase products displayed a wide range of doses and times required to completely degrade the 5 HA products ranging from 16 minutes. CONCLUSION Cosmetic practitioners should familiarize themselves with differences in HA and Hase products. Address correspondence and reprint requests to: Gabriela Casabona, MD, Director of Scientific Department, Ocean Clinic, Av Ramón y Cajal 7, 2nd floor, Marbella, Spain 29601, or e-mail: grcasabona@uol.com.br Supported by Allergan Produtos Farmacêuticos LTDA, São Paulo-SP, Brazil. The authors have indicated no significant interest with commercial supporters. © 2018 by the American Society for Dermatologic Surgery, Inc. Published by Wolters Kluwer Health, Inc. All rights reserved.

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A Predictive Model for Primary Closure Lengths in Mohs Surgery Based on Skin Cancer Type, Dimensions, and Location

BACKGROUND Surgical scar length is a common concern among patients undergoing Mohs micrographic surgery (MMS). OBJECTIVE This study evaluates 3 metrics of preoperative lesion size to determine which correlates best with primary linear closure lengths for nonmelanoma skin cancers (NMSCs) treated with MMS. This metric is then used to develop predictive models for linear closure lengths in 10 different anatomical regions. MATERIALS AND METHODS A retrospective study of 4,049 NMSCs treated with MMS and repaired with primary linear closure was conducted. Primary closure lengths were plotted against preoperative lesion circumference, area, and short axis length. Linear regression analysis was performed. RESULTS Preoperative NMSC circumference correlated best with closure length. Twenty-one of the 28 regression models had coefficients of determination (R2) above 0.5. Closure lengths increased by 0.52 to 1.1 mm, depending on location, for every millimeter increase in preoperative NMSC circumference. CONCLUSION Preoperative lesion circumference is directly proportional to primary closure length and is a better indicator of closure length than preoperative area and short axis for MMS of NMSCs. Closure lengths located on the nasal tip, supratip, or periocular areas are most sensitive to differences in NMSC size. These data might aid Mohs surgeons with preoperative planning for wound reconstruction and patient counseling. Address correspondence and reprint requests to: Mark A. Russell, MD, Department of Dermatology, University of Virginia Health System, 1215 Lee Street, Charlottesville, VA 22903, or e-mail: MR2H@hscmail.mcc.virginia.edu The authors have indicated no significant interest with commercial supporters. © 2018 by the American Society for Dermatologic Surgery, Inc. Published by Wolters Kluwer Health, Inc. All rights reserved.

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Development of a new approach of immunotherapy against scorpion envenoming: Avian IgYs an alternative to equine IgGs

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Publication date: August 2018
Source:International Immunopharmacology, Volume 61
Author(s): Amina Sifi, Sonia Adi-Bessalem, Fatima Laraba-Djebari
Antivenom treatment has been largely used against scorpion stings. Despite their efficacy, the use of mammalian antivenoms may cause adverse effects due to the immune system activation. IgYs from hyperimmunized laying hens against venoms could be a promising alternative to equine IgGs due to the various benefits that these antibodies can provide. Here we report the preparation of specific IgYs by immunizing laying hens with Aah (Androctonus australis hector) scorpion venom.IgYs were isolated from egg yolks by water dilution and salt precipitation methods; they were characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis, western blot and ELISA. The efficiency of these immunoglobulins on the pathophysiological effects induced by Aah venom was assessed by histological and metabolical analysis of the aorta and the heart. The inflammatory response was assessed by evaluating the granulocyte tissue infiltration and oxidative/nitrosative status.Results revealed high IgYs titers against Aah venom by ELISA. Overall, these IgYs seem to protect efficiently mice against envenomation and neutralized the lethal effects of scorpion venom with a high efficacy; the median effective dose (ED50) was 221 μl/2 LD50; i.e. an amount of 79.23 mg of IgY scan neutralize 1 mg of Aah venom. IgY antibodies neutralize effectively the Aah venom lethality and could prevent severe pathological effects induced by scorpion venom and could be used as an effective alternative to equine IgGs against scorpion envenoming.



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Protective effects of ginsenoside Rg1 against lipopolysaccharide/d-galactosamine-induced acute liver injury in mice through inhibiting toll-like receptor 4 signaling pathway

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Publication date: August 2018
Source:International Immunopharmacology, Volume 61
Author(s): Chenqing Ning, Xiaoguang Gao, Changyuan Wang, Xiaokui Huo, Zhihao Liu, Huijun Sun, Xiaobo Yang, Pengyuan Sun, Xiaodong Ma, Qiang Meng, Kexin Liu
Acute liver injury (ALI) is a dramatic liver disease characterized by large areas of inflammation in the liver. This study aimed to investigate the protective effects of ginsenoside Rg1 (Rg1), a biologically active component in Panax ginseng, on lipopolysaccharide/d-galactosamine (LPS/D-GalN)-induced ALI in mice, and meanwhile explore the molecular mechanism in vivo and in vitro. Mice were pretreated with Rg1 for three days prior to LPS (40 μg/kg)/D-GalN (700 mg/kg) administration. The results showed that Rg1 improved the survival rate and reduced the liver to body weight ratios in mice. Rg1 also reduced the production of oxidative markers such as MDA and MPO induced by LPS/D-GalN. In addition, Rg1 significantly decreased the production of inflammatory cytokines including TNF-α, IL-6, IL-1β, Mip-2, Mcp-1, iNOS, and increased the activity of anti-inflammatory cytokine IL-10. Moreover, Rg1 inhibited the protein expression of TLR4 and its downstream genes including NF-κB and MAPKs, which are involved in inflammatory response. Rg1 dramatically reduced oxidative stress by regulating the expression of efflux transporters Mrp2 and various enzymes including GCLC, GCLM, HO-1 and NQO1. However, the changes in these genes and protein induced by Rg1 were abrogated by TLR4 antagonist TAK-242 in vitro. In conclusion, Rg1 had hepatoprotective effect on LPS/D-GalN-induced ALI in mice. The protection may be associated with the inhibition of TLR4. These findings suggest that Rg1 may be a promising agent for prevention against ALI.



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Facile construction of fused benzimidazole-isoquinolinones that induce cell-cycle arrest and apoptosis in colorectal cancer cells

Publication date: Available online 12 June 2018
Source:Bioorganic & Medicinal Chemistry
Author(s): Liu-Jun He, Dong-Lin Yang, Shi-Qiang Li, Ya-Jun Zhang, Yan Tang, Jie Lei, Brendan Frett, Hui-kuan Lin, Hong-yu Li, Zhong-Zhu Chen, Zhi-Gang Xu
Colorectal cancer (CRC) is one of the most frequent, malignant gastrointestinal tumors, and strategies and effectiveness of current therapy are limited. A series of benzimidazole-isoquinolinone derivatives (BIDs) was synthesized and screened to identify novel scaffolds for CRC. Of the compounds evaluated, 7g exhibited the most promising anti-cancer properties. Employing two CRC cell lines, SW620 and HT29, 7g was found to suppress growth and proliferation of the cell lines at a concentration of ∼20 µM. Treatment followed an increase in G2/M cell cycle arrest, which was attributed to cyclin B1 and cyclin-dependent kinase 1 (CDK1) signaling deficiencies with simultaneous enhancement in p21 and p53 activity. In addition, mitochondrial-mediated apoptosis was induced in CRC cells. Interestingly, 7g decreased phosphorylated AKT, mTOR and 4E-BP1 levels, while promoting the expression/stability of PTEN. Since PTEN controls input into the PI3K/AKT/mTOR pathway, antiproliferative effects can be attributed to PTEN-mediated tumor suppression. Collectively, these results suggest that BIDs exert antitumor activity in CRC by impairing PI3K/AKT/mTOR signaling. Against a small kinase panel, 7g exhibited low affinity at 5 µM suggesting anticancer properties likely stem through a non-kinase mechanism. Because of the novelty of BIDs, the structure can serve as a lead scaffold do design new CRC therapies.

Graphical abstract

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Corrigendum to “Nrf2 activators from Glycyrrhiza inflata and their hepatoprotective activities against CCl4-induced liver injury in mice” [Bioorg. Med. Chem. 25 (20) (2017) 5522–5530]

Publication date: Available online 11 June 2018
Source:Bioorganic & Medicinal Chemistry
Author(s): Yan Lin, Yi Kuang, Kai Li, Shuang Wang, Shuai Ji, Kuan Chen, Wei Song, Xue Qiao, Min Ye




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Un nouveau cas d’éruption de type pityriasis rubra pilaire associée à l’inhibiteur de tyrosine kinase ponatinib

Publication date: Available online 11 June 2018
Source:Annales de Dermatologie et de Vénéréologie
Author(s): J. Krygier, G. Leemans, R. Forsyth, A. de Becker, J. Gutermuth, M. Grosber
IntroductionLe pityriasis rubra pilaire (PRP) est un syndrome cutané d'étiologie inconnue dont la plupart des cas sont sporadiques et acquis. Nous rapportons un cinquième cas d'éruption de type PRP associée au ponatinib, un inhibiteur de tyrosine kinase (ITK).ObservationUne femme de 60ans se présentait à la consultation de dermatologie pour une éruption érythémato-squameuse évoluant depuis 2 semaines. La patiente était également suivie en hématologie pour une récidive de leucémie lymphoblastique aiguë. Un traitement par ponatinib avait été débuté 6 semaines plus tôt. Malgré l'aspect peu spécifique de l'histologie cutanée, le diagnostic d'éruption de type PRP induit était posé face à l'image clinique caractéristique. Le traitement par corticoïdes locaux permettait la résolution de l'éruption.DiscussionLa littérature rapporte six cas d'éruption de type PRP associés à la prise d'ITK, dont quatre avec le ponatinib. L'éruption survient dans un délai variant de 2 semaines à 3 mois après le début du traitement. Les corticoïdes locaux prescrits ont donné des résultats mitigés. Une meilleure compréhension de la physiopathologie de ces éruptions associées aux ITK pourrait éclairer les mécanismes pathogéniques du PRP idiopathique.BackgroundPityriasis rubra pilaris (PRP) is a cutaneous syndrome of unknown origin. Most cases are sporadic and acquired. Herein we report a fifth case of PRP-like eruption associated with ponatinib, a tyrosine kinase inhibitor (TKI).Patients and methodsA 60-year-old woman presented at the dermatology department with an erythemato-squamous eruption present for 2weeks. The patient was also being treated in haematology for recurrence of acute lymphoblastic leukaemia. Treatment with ponatinib had been initiated 6weeks earlier. Despite the low specific cutaneous histology, a diagnosis of induced PRP-like eruption was made based on the characteristic clinical aspect. Treatment with local corticosteroids resolved the eruption.DiscussionThe literature contains 6 reported cases of PRP-like eruptions associated with TKI, including 4 with ponatinib. The eruption began from 2weeks to 2–3 months after treatment induction. Prescribed topical corticosteroids have yielded mixed results. A better understanding of the physiopathology of these eruptions associated with TKI could shed light on the pathogenic mechanisms in relation to idiopathic PRP.



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The 8th edition American Joint Committee on gastric cancer pathological staging classification performs well in a population with high proportion of locally advanced disease

Publication date: Available online 11 June 2018
Source:European Journal of Surgical Oncology
Author(s): Shu-Fang Huang, Ti-Hsuan Chien, Wen-Liang Fang, Frank Wang, Chun-Yi Tsai, Jun-Te Hsu, Chun-Nan Yeh, Tse-Ching Chen, Ren-Chin Wu, Cheng-Tang Chiu, Ta-Sen Yeh
BackgroundThe 8th edition of AJCC gastric cancer pathological staging system (AJCC8) derived from the IGCA database needs an external validated in cohorts with higher proportion of advanced disease.Patients and methodsA total of 5,386 gastric cancer patients treated at Chang Gung Memorial Hospital (CGMH) and Veteran General Hospital in Taipei (TVGH) were enrolled. Clinicopathological data of the IGCA series and the CGMH/TVGH cohort were compared. Cumulative survival curves of the CGMH/TVGH cohort as stratified by the AJCC7 and the AJCC8 were compared. Lymph node ratio (LNR) was analyzed in patients with N3b disease.ResultsPatients in the CGMH/TVGH cohort were older and had more advanced tumor stage (stage III, 49% versus 26%, p<0.001) than those in the IGCA cohort. The median survival of stages IIIA, IIIB, and IIIC as defined by the AJCC 8 were 49, 27 and 15 months, respectively, with narrower 95% confidence intervals, in comparison with 62, 30 and 18 months, respectively, as defined by the AJCC7. The AJCC8 exhibited better homogeneity within stages and discriminatory ability between stages, compared to the AJCC7. Six hundred and four patients with N3b disease were stratified by LNR into three subgroups, and their median survival were 31, 17, and 11 months, respectively (p<0.001). LNR further appeared as a powerful outcome predictor of N3b disease (HR, 3.1).ConclusionThe AJCC8 performs well in patients with high proportion of advanced gastric cancer. We recommend that LNR is a supplementary prognostic indicator for N3b disease.



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Δευτέρα 11 Ιουνίου 2018

Dedication

Publication date: Available online 11 June 2018
Source:Radiologic Clinics of North America
Author(s): Savvas Nicolaou, Mohammed F. Mohammed




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Prefrontal D1 Dopamine-Receptor Neurons and Delta Resonance in Interval Timing

Abstract
Considerable evidence has shown that prefrontal neurons expressing D1-type dopamine receptors (D1DRs) are critical for working memory, flexibility, and timing. This line of work predicts that frontal neurons expressing D1DRs mediate cognitive processing. During timing tasks, one form this cognitive processing might take is time-dependent ramping activity—monotonic changes in firing rate over time. Thus, we hypothesized the prefrontal D1DR+ neurons would strongly exhibit time-dependent ramping during interval timing. We tested this idea using an interval-timing task in which we used optogenetics to tag D1DR+ neurons in the mouse medial frontal cortex (MFC). While 23% of MFC D1DR+ neurons exhibited ramping, this was significantly less than untagged MFC neurons. By contrast, MFC D1DR+ neurons had strong delta-frequency (1–4 Hz) coherence with other MFC ramping neurons. This coherence was phase-locked to cue onset and was strongest early in the interval. To test the significance of these interactions, we optogenetically stimulated MFC D1DR+ neurons early versus late in the interval. We found that 2-Hz stimulation early in the interval was particularly effective in rescuing timing-related behavioral performance deficits in dopamine-depleted animals. These findings provide insight into MFC networks and have relevance for disorders such as Parkinson's disease and schizophrenia.

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Neural Overlap in Item Representations Across Episodes Impairs Context Memory

Abstract
We frequently encounter the same item in different contexts, and when that happens, memories of earlier encounters can get reactivated. We examined how existing memories are changed as a result of such reactivation. We hypothesized that when an item's initial and subsequent neural representations overlap, this allows the initial item to become associated with novel contextual information, interfering with later retrieval of the initial context. Specifically, we predicted a negative relationship between representational similarity across repeated experiences of an item and subsequent source memory for the initial context. We tested this hypothesis in an fMRI study, in which objects were presented multiple times during different tasks. We measured the similarity of the neural patterns in lateral occipital cortex that were elicited by the first and second presentations of objects, and related this neural overlap score to subsequent source memory. Consistent with our hypothesis, greater item-specific pattern similarity was linked to worse source memory for the initial task. In contrast, greater reactivation of the initial context was associated with better source memory. Our findings suggest that the influence of novel experiences on an existing context memory depends on how reliably a shared component (i.e., item) is represented across these episodes.

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