PISCOM: a new procedure for epilepsy combining ictal SPECT and interictal PET

Abstract

Purpose

We present a modified version of the SISCOM procedure that uses interictal PET instead of interictal SPECT for seizure onset zone localization. We called this new nuclear imaging processing technique PISCOM (PET interictal subtracted ictal SPECT coregistered with MRI).

Methods

We retrospectively studied 23 patients (age range 4–61 years) with medically refractory epilepsy who had undergone MRI, ictal SPECT, interictal SPECT and interictal FDG PET and who had been seizure-free for at least 2 years after surgical treatment. FDG PET images were reprocessed (rFDG PET) to assimilate SPECT features for image subtraction. Interictal SPECT and rFDG PET were compared using statistical parametric mapping (SPM). PISCOM and SISCOM images were evaluated visually and using an automated volume of interest-based analysis. The results of the two studies were compared with each other and with the known surgical resection site.

Results

SPM showed no significant differences in cortical activity between SPECT and rFDG PET images. PISCOM and SISCOM showed equivalent results in 17 of 23 patients (74%). The seizure onset zone was successfully identified in 19 patients (83%) by PISCOM and in 17 (74%) by SISCOM: in 15 patients (65%) the two techniques showed concordant successful results. The volume of interest-based analysis showed no significant differences between PISCOM and SISCOM in identifying the extension of the seizure onset zone. However, PISCOM showed a lower amount of indeterminate activity due to propagation, background or artefacts.

Conclusion

Preliminary findings of this initial proof-of-concept study suggest that perfusion and glucose metabolism in the cerebral cortex can be correlated and that PISCOM may be a valid technique for identification of the seizure onset zone. However, further studies are needed to validate these results.

https://ift.tt/2M49Xcy

The influence of aging on the comparative terrestrial ecotoxicity potential of copper and zinc in soils

Abstract

Metal exposure to terrestrial organism is influenced by the reactivity of the solid-phase metal pool. Aging is one of the important factors that control the reactivity of the solid-phase metal pool in soil. In this study, the selected 13 soils were collected from different locations of China, representing different soil types. The reactivity variation of spiked Cu and Zn with aging was assessed in these 13 soils, and their comparative toxicity potentials (CTPs) were also calculated. The median reactive fractions (f_reactive) of Cu and Zn with 95% confidence intervals were 1.6 × 10⁻² (3.5 × 10⁻⁶ to 2.2 × 10⁻¹) and 0.10 (9.1 × 10⁻⁴ to 0.44) kg_reactive/kg_total, and the median CTPs for Cu and Zn were 2.09 (8.1 × 10⁻⁴ to 2.2 × 10⁴) and 0.85 (8.5 × 10⁻⁴ to 7.2 × 10²) m³/kg day, respectively. The statistical analysis indicated that aging variability in the CTP of Cu and Zn was mainly associated with the variability in soil organic carbon and pH. These results stress the importance of dealing with aging in the calculation of CTPs for terrestrial ecotoxicity of metals.

https://ift.tt/2v7hWPF

Physiological and anatomical responses of a common beach grass to crude oil pollution

Abstract

Oil pollution is one potential consequence of industry development, and oil contamination occurs in countries around the world. However, few studies have examined the detrimental effects of oil on plant anatomy. Therefore, the objectives of this study were (1) to determine the impacts of crude oil on the physiological and anatomical parameters of Ischaemum muticum L. (Poaceae) and (2) to examine its potential as a bioindicator of oil pollution. Experimental plants were treated with one of four concentrations of crude oil (1%, 2%, 3%, and 4% volume/weight) and compared to control plants (no oil applied). Four physiological and 23 anatomical parameters were measured 7, 15, 30, 45, and 60 days after treatment. Crude oil negatively affected both physiological traits (leaf width and chlorophyll content) and anatomical traits (midrib vascular bundle height, leaf cutin thickness, leaf vascular bundle width and height, abaxial and adaxial margin cutin thickness, adaxial stomata density, adaxial short cell width, and abaxial long cell width). In general, the affected traits were modified by even the lowest oil concentration tested (1%). We discuss the potential of I. muticum as a bioindicator of oil pollution, given its prevalence in coastal areas of the paleotropics and its sensitivity to oil contamination.

https://ift.tt/2AuOacL

The role of Complementary Learning Systems in learning and consolidation in a quasi-regular domain

Publication date: Available online 1 August 2018

Source: Cortex

Author(s): Jelena Mirković, Lydia Vinals, M. Gareth Gaskell

Abstract

We examine the role of off-line memory consolidation processes in the learning and retention of a new quasi-regular linguistic system similar to the English past tense. Quasi-regular systems are characterized by a dominance of systematic, regular forms (e.g., walk-walked, jump-jumped) alongside a smaller number of high frequency irregulars (e.g., sit-sat, go-went), and are found across many cognitive domains, from spelling-sound mappings to inflectional morphology to semantic cognition. Participants were trained on the novel morphological system using an artificial language paradigm, and then tested after different delays. Based on a complementary systems account of memory, we predicted that irregular forms would show stronger off-line changes due to consolidation processes. Across two experiments, participants were tested either immediately after learning, 12 hours later with or without sleep, or 24 hours later. Testing involved generalization of the morphological patterns to previously unseen words (both experiments) as well as recall of the trained words (Experiment 2). In generalization, participants showed 'default' regularization across a range of novel forms, as well as irregularization for previously unseen items that were similar to unique high-frequency irregular trained forms. Both patterns of performance remained stable across the delays. Generalizations involving competing tendencies to regularize and irregularize were balanced between the two immediately after learning. Crucially, at both 12-hour delays the tendency to irregularize in these cases was strengthened, with further strengthening after 24 hours. Consolidated knowledge of both regular and irregular trained items contributed significantly to generalization performance, with evidence of strengthening of irregular forms and weakening of regular forms. We interpret these findings in the context of a complementary systems model, and discuss how maintenance, strengthening, and forgetting of the new memories across sleep and wake can play a role in acquiring quasi-regular systems.

https://ift.tt/2KfjgVi

Disordered eating attitudes in female students of An-Najah National University: a cross-sectional study

Abstract

Background

Eating disorders (ED) are serious psychiatric disorders characterized by unhealthy eating habits. There is a limited number of studies on eating disorders among female university students in Arab countries. Therefore, the objective of this study was to examine the prevalence of disordered eating attitudes (EA) among female students at An-Najah National University, Palestine.

Methods

A survey study on 2001 female students at An-Najah National University was carried out. The Sick, Control, One Stone, Fat, Food (SCOFF) screening questionnaire and the Eating Attitudes Test (EAT-26) were used.

Results

Of the 2001 participants, 28.6% scored ≥ 20 on the EAT-26 while 38.2% scored ≥ 2 on the SCOFF scale. A significant positive correlation was found between body mass index (BMI) and EAT-26 and SCOFF scores. There was a significant difference in EAT-26 (p < .01) and SCOFF scores (p = .037) between different academic specializations. Female students in non-scientific fields (arts and humanities) obtained higher scores than female students in scientific/medical fields. Age was significantly and negatively correlated with EAT-26 scores but not with SCOFF scores. Approximately 85% of students with scores in the "high risk" category of the EAT-26 scale endorsed the item "I am terrified about being overweight".

Conclusion

Awareness regarding appropriate nutrition in relation to body weight is needed among female university students. A general university elective course in this regard might be helpful.

https://ift.tt/2LFZqrL

A recessive mutation in the DSP gene linked to cardiomyopathy, skin fragility and hair defects impairs the binding of desmoplakin to epidermal keratins and the muscle‐specific intermediate filament desmin

British Journal of Dermatology, EarlyView.


https://ift.tt/2mZbOEH

Ear lobe rotation flap for the reconstruction of full-thickness defects of the middle third of the auricle

Abstract

The authors propose a novel surgical technique for reconstruction of full-thickness defects of the middle portion of the auricle including the helix and the antihelix up to the neighboring portion of the concha and sparing the whole of the ear lobe. It is a single-stage procedure that is indicated when a large, redundant, and pendulous earlobe exists as typically occurs in the elderly patient. The earlobe is rotated into the full-thickness ear defect and fits as an inlay between two cartilaginous stumps. The ear lobe presents two anatomical patterns: the pendulous or free one, with the ear lobe lying free from the cheek, and the non-pendulous or attached one, where the ear lobe is attached to the cheek. Donor site deformity is therefore limited to the conversion of a pendulous ear lobe pattern into an attached one. Surgery may be scheduled in an outpatient basis as the procedure is easy to plan, is fast to perform, and is carried out under local anesthesia.

Level of Evidence: Level IV, therapeutic study.

https://ift.tt/2LMdkIr

An unusual case of giant rhinophyma

Abstract

Rosacea is a rather common and frequently diagnosed condition of the skin and may in some cases progress to rhinophyma. This is a case report of a patient with a giant rhinophyma of 358 g. He claimed his first symptoms 5 years prior to our first clinical assessment. We performed an excision of the tumor mass by scalpel and a CO₂ laser treatment of the remaining skin surface. Post-surgical therapy only included topical treatment with an ointment containing bacitracin zinc and neomycin sulphate to prevent infections. After stable wound closure, we had the chance to examine the patient after a period of 7.5 years with remarkable aesthetical results.

Level of Evidence: Level V, therapeutic study.

https://ift.tt/2O1zSlL

Scholar : These new articles for Danish Journal of Archaeology are available online

The online platform for Taylor & Francis Online content New for Danish Journal of Archaeology and online now on Taylor & Francis Online: Original Articles Polynesians of the Atlantic? Precedents, potentials, and pitfalls in Oceanic analogies of the Vikings | Neil Price & John Ljungkvist Pages: 1-6 | DOI: 10.1080/21662282.2018.1498567 To update which email alerts you receive, manage your alerts within the My Account area. Unsubscribe from new content alerts for this journal (both new issue and latest article notifications) with one click. If you need any further help, please contact us at support@tandfonline.com Please do not reply to this email. To ensure that you receive your alerts and information from Taylor & Francis Online, please add "alerts@tandfonline.com" and "info@tandfonline.com" to your safe senders list. Taylor & Francis, an Informa business. Taylor & Francis is a trading name of Informa UK Limited, registered in England under no. 1072954. Registered office: 5 Howick Place, London, SW1P 1WG.

Decoding the processing stages of mental arithmetic with magnetoencephalography

Publication date: Available online 31 July 2018

Source: Cortex

Author(s): Pedro Pinheiro-Chagas, Manuela Piazza, Stanislas Dehaene

Abstract

Elementary arithmetic is highly prevalent in our daily lives. However, despite decades of research, we are only beginning to understand how the brain solves simple calculations. Here, we applied machine learning techniques to magnetoencephalography (MEG) signals in an effort to decompose the successive processing stages and mental transformations underlying elementary arithmetic. Adults subjects verified single-digit addition and subtraction problems such as 3+2=9 in which each successive symbol was presented sequentially. MEG signals revealed a cascade of partially overlapping brain states. While the first operand could be transiently decoded above chance level, primarily based on its visual properties, the decoding of the second operand was more accurate and lasted longer. Representational similarity analyses suggested that this decoding rested on both visual and magnitude codes. We were also able to decode the operation type (additions vs. subtraction) during practically the entire trial after the presentation of the operation sign. At the decision stage, MEG indicated a fast and highly overlapping temporal dynamics for (1) identifying the proposed result, (2) judging whether it was correct or incorrect, and (3) pressing the response button. Surprisingly, however, the internally computed result could not be decoded. Our results provide a first comprehensive picture of the unfolding processing stages underlying arithmetic calculations at a single-trial level, and suggest that externally and internally generated neural codes may have different neural substrates.

https://ift.tt/2Oz8CfI

Omalizumab for the treatment of chronic spontaneous urticaria in daily clinical practice in South Spain

Dermatologic Therapy, EarlyView.


https://ift.tt/2O0riUs

Kava to Reduce Tobacco Use in Head & Neck Cancer Survivors

Condition:   Tobacco Use Cessation
Interventions:   Drug: Kava;   Other: Placebo
Sponsor:   University of Florida
Not yet recruiting

https://ift.tt/2KiUovQ

Efficacy of Fluoroscopic Guided Atlantoaxial Joint Injection on Head and Neck Pain and Sleep Quality in RA Patients

Conditions:   Pain, Head;   Sleep Disturbance
Intervention:   Drug: Steroids
Sponsor:   Assiut University
Recruiting

https://ift.tt/2LPaUsy

Continous Popliteal Block for Microvascular Free Flap Reconstruction in Ear, Nose and Throat Surgery

Conditions:   Head and Neck Cancer;   Pain, Musculoskeletal
Interventions:   Drug: Levobupivacaine;   Drug: Saline Solution
Sponsor:   Region Skane
Not yet recruiting

https://ift.tt/2KexLJf

Effects of reducing light-curing time of a high-power LED device on shear bond strength of brackets

Abstract

Purpose

To assess the effects of reducing the curing time of a high-power light-emitting diode (LED) unit (Valo, Ultradent, South Jordan, UT, USA) on shear bond strength (SBS) of metal brackets and on the amount of adhesive remnant of two orthodontic composites.

Methods

Eighty human premolars were divided into four groups (G1–4) according to curing time and composite: G1 (Transbond XT, 6 s), G2 (Opal Bond MV, 6 s), G3 (Transbond XT, 3 s), and G4 (Opal Bond MV, 3 s). Twenty-four hours after bonding, brackets were subject to a SBS test performed with a universal testing machine. Enamel surface was analyzed by SEM and the amount of adhesive remnant was assessed by the Image J software area calculation tool. Two-way analysis of variance was used for statistical analysis of SBS data, while Friedman and Mann–Whitney post hoc tests were used to analyze data on the amount of adhesive remnant.

Results

Time and composite significantly affected SBS (p < 0.001). The 6 s curing showed a higher SBS value (21.56 MPa) in comparison to 3 s curing (15.79 MPa). Transbond XT composite showed a significantly higher SBS value (21.06 MPa) compared to Opal Bond MV (16.29 MPa). After the SBS test, Opal Bond MV showed a significantly greater amount of composite adhered to enamel (p < 0.001).

Conclusion

Reducing exposure time from 6 to 3 s significantly decreased mean values of SBS, even with the use of a high-power LED unit. Reduction in time did not affect the amount of adhesive remnant.

https://ift.tt/2KcRdGf

Long-Term Results of Deep Brain Stimulation of the Mamillotegmental Fasciculus in Chronic Cluster Headache

Background: Deep brain stimulation (DBS) and the proper target for chronic cluster headache (CCH) are still subjects of controversy. Objectives: We present our long-term results of analysis of the target and its structural connectivity. Methods: Fifteen patients with drug-resistant CCH underwent DBS in coordinates 4 mm lateral to the III ventricular wall and 2 mm behind and 5 mm below the intercommissural point. The clinical parameters recorded were the number of weekly attacks, pain intensity, and duration of the headache. Structural connectivity was studied using 3-T MR diffusion tensor imaging (DTI). Results: All of our patients improved from a mean of 39 attacks/week to 2; pain intensity decreased from 9 to 3 out of 10, and the mean cephalalgia duration decreased from 53 to 8 min. The mean stereotactic coordinates of the effective contact location were 6.1 mm lateral to the midcommissural point and 1.2 mm behind and 4.0 mm below the intercommissural point. DTI analysis showed that this target was connected to tracts and nuclei of the posterior mesencephalic tegmentum, specifically the dorsal longitudinal and mamillotegmental fasciculi. Conclusions: Our data showed DBS to be a safe and useful procedure for the treatment of drug-resistant CCH; the rate of improvement was higher than those found in other series. Although these are promising results, larger series targeting those fasciculi with a longer follow-up are needed.
Stereotact Funct Neurosurg

https://ift.tt/2LKHEmL

Reference intervals for neonatal thyroid function tests in the first 7 days of life

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Issue: Ahead of print


https://ift.tt/2OvafLf

Is there an association between thyrotropin levels within the normal range and birth growth parameters in full-term newborns?

Journal Name: Journal of Pediatric Endocrinology and Metabolism
Issue: Ahead of print


https://ift.tt/2App2UT

Effects of reducing light-curing time of a high-power LED device on shear bond strength of brackets

Abstract

Purpose

To assess the effects of reducing the curing time of a high-power light-emitting diode (LED) unit (Valo, Ultradent, South Jordan, UT, USA) on shear bond strength (SBS) of metal brackets and on the amount of adhesive remnant of two orthodontic composites.

Methods

Eighty human premolars were divided into four groups (G1–4) according to curing time and composite: G1 (Transbond XT, 6 s), G2 (Opal Bond MV, 6 s), G3 (Transbond XT, 3 s), and G4 (Opal Bond MV, 3 s). Twenty-four hours after bonding, brackets were subject to a SBS test performed with a universal testing machine. Enamel surface was analyzed by SEM and the amount of adhesive remnant was assessed by the Image J software area calculation tool. Two-way analysis of variance was used for statistical analysis of SBS data, while Friedman and Mann–Whitney post hoc tests were used to analyze data on the amount of adhesive remnant.

Results

Time and composite significantly affected SBS (p < 0.001). The 6 s curing showed a higher SBS value (21.56 MPa) in comparison to 3 s curing (15.79 MPa). Transbond XT composite showed a significantly higher SBS value (21.06 MPa) compared to Opal Bond MV (16.29 MPa). After the SBS test, Opal Bond MV showed a significantly greater amount of composite adhered to enamel (p < 0.001).

Conclusion

Reducing exposure time from 6 to 3 s significantly decreased mean values of SBS, even with the use of a high-power LED unit. Reduction in time did not affect the amount of adhesive remnant.

https://ift.tt/2KcRdGf

The Clinical Cases of Geleophysic Dysplasia: One Gene, Different Phenotypes.

Related Articles

The Clinical Cases of Geleophysic Dysplasia: One Gene, Different Phenotypes.

Case Rep Endocrinol. 2018;2018:8212417

Authors: Globa E, Zelinska N, Dauber A

Abstract
Background: Geleophysic dysplasia is a rare multisystem disorder that principally affects the bones, joints, heart, and skin. This condition is inherited either in an autosomal dominant pattern due to FBN1 mutations or in an autosomal recessive pattern due to ADAMTSL2 mutations. Two patients with unaffected parents from unrelated families presented to their endocrinologist with severe short stature, resistant to growth hormone treatment. Routine endocrine tests did not reveal an underlying etiology. Exome sequencing was performed in each family. Our two patients, harboring de novo heterozygous FBN1 mutations p.Tyr1696Asp and p.Cys1748Ser, had common clinical symptoms such as severe short stature, characteristic facial features, short hands and feet, and limitation of joint movement. However, one patient had severe cardiac involvement whereas the other patient had tracheal stenosis requiring tracheostomy placement.
Conclusions: Patients with severe dwarfism, skeletal anomalies, and other specific syndromic features (e.g., tracheal stenosis and cardiac valvulopathy) should undergo genetic testing to exclude acromelic dysplasia syndromes.

PMID: 30057829 [PubMed]

https://ift.tt/2NZNy0B

Fever of Unknown Origin: Could It Be a Pheochromocytoma? A Case Report and Review of the Literature.

Related Articles

Fever of Unknown Origin: Could It Be a Pheochromocytoma? A Case Report and Review of the Literature.

Case Rep Endocrinol. 2018;2018:3792691

Authors: Siddiqui UM, Matta S, Wessolossky MA, Haas R

Abstract
Pheochromocytomas are rare tumors that arise from the adrenal medulla, with an incidence of less than 1 per 100,000 person-years. These tumors are characterized by excess catecholamine secretion and classically present with the triad of headaches, palpitations, and sweating episodes. However, the clinical presentation can be quite variable. Herein, we present a patient who presented with persistent fevers. An adrenal mass was incidentally discovered during the extensive investigation for the fever of unknown origin. Consequently, blood and urine tests were done and found to be consistent with a pheochromocytoma. The resection of this pheochromocytoma resulted in resolution of fevers. It is hypothesized that fevers in patients with pheochromocytomas occur due to the excess catecholamine or possibly due to interleukins. This clinical presentation serves as a learning point that adrenal incidentalomas in the setting of fever of unknown origin should not be ignored. It also reminds clinicians that pheochromocytomas which present with fevers may have tumor necrosis and many such patients are at risk for multisystem crises.

PMID: 30057828 [PubMed]

https://ift.tt/2OwWmMp

Possible Neurobiological Underpinnings of Homosexuality and Gender Dysphoria

Abstract

Although frequently discussed in terms of sex dimorphism, the neurobiology of sexual orientation and identity is unknown. We report multimodal magnetic resonance imaging data, including cortical thickness (Cth), subcortical volumes, and resting state functional magnetic resonance imaging, from 27 transgender women (TrW), 40 transgender men (TrM), and 80 heterosexual (40 men) and 60 homosexual cisgender controls (30 men). These data show that whereas homosexuality is linked to cerebral sex dimorphism, gender dysphoria primarily involves cerebral networks mediating self–body perception. Among the homosexual cisgender controls, weaker sex dimorphism was found in white matter connections and a partly reversed sex dimorphism in Cth. Similar patterns were detected in transgender persons compared with heterosexual cisgender controls, but the significant clusters disappeared when adding homosexual controls, and correcting for sexual orientation. Instead, both TrW and TrM displayed singular features, showing greater Cth as well as weaker structural and functional connections in the anterior cingulate-precuneus and right occipito-parietal cortex, regions known to process own body perception in the context of self.

https://ift.tt/2NUuil4

Revealing a Cortical Circuit Responsive to Predatory Threats and Mediating Contextual Fear Memory

Abstract

The ventral part of the anteromedial thalamic nucleus (AMv) receives substantial inputs from hypothalamic sites that are highly responsive to a live predator or its odor trace and represents an important thalamic hub for conveying predatory threat information to the cerebral cortex. In the present study, we begin by examining the cortico-amygdalar-hippocampal projections of the main AMv cortical targets, namely, the caudal prelimbic, rostral anterior cingulate, and medial visual areas, as well as the rostral part of the ventral retrosplenial area, one of the main targets of the anterior cingulate area. We observed that these areas form a clear cortical network. Next, we revealed that in animals exposed to a live cat, all of the elements of this circuit presented a differential increase in Fos, supporting the idea of a predator threat-responsive cortical network. Finally, we showed that bilateral cytotoxic lesions in each element of this cortical network did not change innate fear responses but drastically reduced contextual conditioning to the predator-associated environment. Overall, the present findings suggest that predator threat has an extensive representation in the cerebral cortex and revealed a cortical network that is responsive to predatory threats and exerts a critical role in processing fear memory.

https://ift.tt/2Ox9XUf

Interrogating the Relationship Between Schizotypy, the Catechol-O-Methyltransferase (COMT) Val158Met Polymorphism, and Neuronal Oscillatory Activity

Abstract

The COMT Val158Met polymorphism affects the availability of synaptic dopamine in the prefrontal cortex and has been widely studied as a genetic risk factor for psychosis. Schizotypy is associated with an increased risk of psychosis, with some studies implicating similar neurobiological mechanisms to schizophrenia. The present study sought to interrogate the link between the COMT Val158Met polymorphism and schizotypy using electroencephalogram (EEG) to identify neurophysiological mechanisms underpinning psychosis risk. Neurotypical (N = 91) adults were genotyped for the COMT Val158Met polymorphism, completed the Schizotypal Personality Questionnaire (SPQ), and had eyes open resting-state EEG recorded for 4 min. SPQ suspiciousness subscale scores were higher for individuals homozygous for Val/Val and Met/Met versus Val/Met genotypes. Delta, theta, alpha-2, beta-1, and beta-2 amplitudes were lower for Val/Val than Met/Met individuals. Lower theta amplitudes were correlated with higher total SPQ scores (P = 0.050), and multiple regression revealed that higher delta, and lower theta and beta-2 amplitudes (but not COMT genotype) best predicted total SPQ scores (P = 0.014). This study demonstrates the importance of COMT genotype in determining trait suspiciousness and EEG oscillatory activity. It also highlights relationships between dopaminergic alterations, EEG and schizotypy that are dissimilar to those observed in schizophrenia.

https://ift.tt/2NY49BP

Role of the Default Mode Network in Cognitive Transitions

Abstract

A frequently repeated finding is that the default mode network (DMN) shows activation decreases during externally focused tasks. This finding has led to an emphasis in DMN research on internally focused self-relevant thought processes. A recent study, in contrast, implicates the DMN in substantial externally focused task switches. Using functional magnetic resonance imaging, we scanned 24 participants performing a task switch experiment. Whilst replicating previous DMN task switch effects, we also found large DMN increases for brief rests as well as task restarts after rest. Our findings are difficult to explain using theories strictly linked to internal or self-directed cognition. In line with principal results from the literature, we suggest that the DMN encodes scene, episode or context, by integrating spatial, self-referential, and temporal information. Context representations are strong at rest, but rereference to context also occurs at major cognitive transitions.

https://ift.tt/2OwTLC9

Prefrontal Control Over Occipital Responses to Crossmodal Overlap Varies Across the Congruency Spectrum

Abstract

While matched crossmodal information is known to facilitate object recognition, it is unclear how our perceptual systems encode the more gradual congruency variations that occur in our natural environment. Combining visual objects with odor mixtures to create a gradual increase in semantic object overlap, we demonstrate high behavioral acuity to linear variations of olfactory–visual overlap in a healthy adult population. This effect was paralleled by a linear increase in cortical activation at the intersection of occipital fusiform and lingual gyri, indicating linear encoding of crossmodal semantic overlap in visual object recognition networks. Effective connectivity analyses revealed that this integration of olfactory and visual information was achieved by direct information exchange between olfactory and visual areas. In addition, a parallel pathway through the superior frontal gyrus was increasingly recruited towards the most ambiguous stimuli. These findings demonstrate that cortical structures involved in object formation are inherently crossmodal and encode sensory overlap in a linear manner. The results further demonstrate that prefrontal control of these processes is likely required for ambiguous stimulus combinations, a fact of high ecological relevance that may be inappropriately captured by common task designs juxtaposing congruency and incongruency.

https://ift.tt/2vkzt6n

ACC Sulcal Patterns and Their Modulation on Cognitive Control Efficiency Across Lifespan: A Neuroanatomical Study on Bilinguals and Monolinguals

Abstract

The anterior cingulate cortex (ACC) is a key structure implicated in the regulation of cognitive control (CC). Previous studies suggest that variability in the ACC sulcal pattern—a neurodevelopmental marker unaffected by maturation or plasticity after birth—is associated with intersubject differences in CC performance. Here, we investigated whether bilingual experience modulates the effects of ACC sulcal variability on CC performance across the lifespan. Using structural MRI, we first established the distribution of the ACC sulcal patterns in a large sample of healthy individuals (N = 270) differing on gender and ethnicity. Second, a participants' subsample (N = 157) was selected to test whether CC performance was differentially affected by ACC sulcation in bilinguals and monolinguals across age. A prevalent leftward asymmetry unaffected by gender or ethnicity was reported. Sulcal variability in the ACC predicted CC performance differently in bilinguals and monolinguals, with a reversed pattern of structure–function relationship: asymmetrical versus symmetrical ACC sulcal patterns were associated with a performance advantage in monolinguals and a performance detriment to bilinguals and vice versa. Altogether, these findings provide novel insights on the dynamic interplay between early neurodevelopment, environmental background and cognitive efficiency across age.

https://ift.tt/2LBQpjw

Hippocampal Network Oscillations Rescue Memory Consolidation Deficits Caused by Sleep Loss

Abstract

Oscillations in the hippocampal network during sleep are proposed to play a role in memory storage by patterning neuronal ensemble activity. Here we show that following single-trial fear learning, sleep deprivation (which impairs memory consolidation) disrupts coherent firing rhythms in hippocampal area CA1. State-targeted optogenetic inhibition of CA1 parvalbumin-expressing (PV+) interneurons during postlearning NREM sleep, but not REM sleep or wake, disrupts contextual fear memory (CFM) consolidation in a manner similar to sleep deprivation. NREM-targeted inhibition disrupts CA1 network oscillations which predict successful memory storage. Rhythmic optogenetic activation of PV+ interneurons following learning generates CA1 oscillations with coherent principal neuron firing. This patterning of CA1 activity rescues CFM consolidation in sleep-deprived mice. Critically, behavioral and optogenetic manipulations that disrupt CFM also disrupt learning-induced stabilization of CA1 ensembles' communication patterns in the hours following learning. Conversely, manipulations that promote CFM also promote long-term stability of CA1 communication patterns. We conclude that sleep promotes memory consolidation by generating coherent rhythms of CA1 network activity, which provide consistent communication patterns within neuronal ensembles. Most importantly, we show that this rhythmic patterning of activity is sufficient to promote long-term memory storage in the absence of sleep.

https://ift.tt/2vowdqv

Reward-Driven Arousal Impacts Preparation to Perform a Task via Amygdala–Caudate Mechanisms

Abstract

Preparing for a challenging task can increase physiological arousal, in particular when potential incentives are large (e.g., a solo musical performance in front of an audience). Here, we examine how potential reward and its influence on arousal, measured by pupil dynamics, are represented in the brain while preparing for a challenging task. We further ask how neural representations during preparation relate to actual performance. Trials resulting in performance failure were characterized by increased pupil dilation as a function of increasing reward magnitude during preparation. Such failure trials were also associated with activation of the right amygdala representing pupil dilation, and the left caudate representing reward magnitude. Notably, increases in functional connectivity between amygdala and caudate preceded performance failure. These findings highlight increased connectivity between neural regions representing reward and arousal in circumstances where reward-driven arousal impairs performance.

https://ift.tt/2OwLxu4

Control Engagement During Sentence and Inhibition fMRI Tasks in Children With Reading Difficulties

Abstract

Recent reading research implicates executive control regions as sites of difference in struggling readers. However, as studies often employ only reading or language tasks, the extent of deviation in control engagement in children with reading difficulties is not known. The current study investigated activation in reading and executive control brain regions during both a sentence comprehension task and a nonlexical inhibitory control task in third–fifth grade children with and without reading difficulties. We employed both categorical (group-based) and individual difference approaches to relate reading ability to brain activity. During sentence comprehension, struggling readers had less activation in the left posterior temporal cortex, previously implicated in language, semantic, and reading research. Greater negative activity (relative to fixation) during sentence comprehension in a left inferior parietal region from the executive control literature correlated with poorer reading ability. Greater comprehension scores were associated with less dorsal anterior cingulate activity during the sentence comprehension task. Unlike the sentence task, there were no significant differences between struggling and nonstruggling readers for the nonlexical inhibitory control task. Thus, differences in executive control engagement were largely specific to reading, rather than a general control deficit across tasks in children with reading difficulties, informing future intervention research.

https://ift.tt/2NZxbRQ

The Timing of Sensory-Guided Behavioral Response is Represented in the Mouse Primary Somatosensory Cortex

Abstract

Whisker-guided decision making in mice is thought to critically depend on information processing occurring in the primary somatosensory cortex. However, it is not clear if neuronal activity in this "early" sensory region contains information about the timing and speed of motor response. To address this question we designed a new task in which freely moving mice learned to associate a whisker stimulus to reward delivery. The task was tailored in such a way that a wide range of delays between whisker stimulation and reward collection were observed due to differences of motivation and perception. After training, mice were anesthetized and neuronal responses evoked by stimulating trained and untrained whiskers were recorded across several cortical columns of barrel cortex. We found a strong correlation between the delay of the mouse behavioral response and the timing of multiunit activity evoked by the trained whisker, outside its principal cortical column, in layers 4 and 5A but not in layer 2/3. Circuit mapping ex vivo revealed this effect was associated with a weakening of layer 4 to layer 2/3 projection. We conclude that the processes controlling the propagation of key sensory inputs to naive cortical columns and the timing of sensory-guided action are linked.

https://ift.tt/2OuC06s

Dynamic Reorganization of Motor Networks During Recovery from Partial Spinal Cord Injury in Monkeys

Abstract

After spinal cord injury (SCI), the motor-related cortical areas can be a potential substrate for functional recovery in addition to the spinal cord. However, a dynamic description of how motor cortical circuits reorganize after SCI is lacking. Here, we captured the comprehensive dynamics of motor networks across SCI in a nonhuman primate model. Using electrocorticography over the sensorimotor areas in monkeys, we collected broadband neuronal signals during a reaching-and-grasping task at different stages of recovery of dexterous finger movements after a partial SCI at the cervical levels. We identified two distinct network dynamics: grasping-related intrahemispheric interactions from the contralesional premotor cortex (PM) to the contralesional primary motor cortex (M1) in the high-γ band (>70 Hz), and motor-preparation-related interhemispheric interactions from the contralesional to ipsilesional PM in the α and low-β bands (10–15 Hz). The strengths of these networks correlated to the time course of behavioral recovery. The grasping-related network showed enhanced activation immediately after the injury, but gradually returned to normal while the strength of the motor-preparation-related network gradually increased. Our findings suggest a cortical compensatory mechanism after SCI, where two interdependent motor networks redirect activity from the contralesional hemisphere to the other hemisphere to facilitate functional recovery.

https://ift.tt/2NT0TaQ

Large Nasal Defects with Exposed Cartilage: The Folded Transposition Flap as an Innovative Alternative to the Paramedian Forehead Flap

Background: Skin cancer removal surgery involving the tip or dorsum of the nose often results in large-sized defects with exposure of cartilage. In such cases, the paramedian forehead flap is a frequently used reconstruction technique; however, this method is complex and can result in a cosmetically unsatisfying outcome. Objective: To describe the folded transposition flap as an aesthetically pleasing alternative to the paramedian forehead flap for large nasal defects with exposed cartilage. Methods: The folded transposition flap is a 2-stage surgical modification of the transposition flap. In the first stage, an overlong axial cheek pedicle is used to cover the defect. In the second stage, the flap is thinned and the nasal scars are revised. Results: All 4 patients experienced aesthetically pleasing results. Conclusion: The folded transposition flap is an alternative for reconstructing large surgical defects of the nasal tip or distal dorsum of the nose.
Dermatology

https://ift.tt/2vnXskW

Sodium butyrate supplementation ameliorates diabetic inflammation in db/db mice

Endotoxemia has been recognized to be closely accompanied with type 2 diabetes mellitus (T2DM) and is responsible for many diabetic complications. Recent study suggests the potential role of butyrate, a short-chain fatty acid (SCFA) from microbiota metabolite, on T2DM. Gut-leak is a key event in diabetic-endotoxemia. To investigate if butyrate could ameliorate diabetic-endotoxemia, both in vivo and in vitro experiments were carried out in the present study. The effect of butyrate supplementation on blood HbA1c and inflammatory cytokines were determined in db/db mice; gut barrier integrity and expression of tight junction proteins were investigated both in vivo and in vitro. Oral butyrate administration significantly decreased blood HbA1c, inflammatory cytokines and LPS in db/db mice; inflammatory cell infiltration was reduced, and gut integrity and intercellular adhesion molecules were increased as detected by HE staining, immunohistochemistry and Western blot. By gut microbiota assay, ratio of Firmicutes:Bacteroidetes for gut microbiota was reduced by butyrate. In Caco-2 cells, butyrate significantly promoted cell proliferation, decreased inflammatory cytokines' secretion, enhanced cell anti-oxidative stress ability and preserved the epithelial monocellular integrity, which was damaged by LPS. The present findings demonstrated that butyrate supplementation could ameliorate diabetic-endotoxemia in db/db mice via restoring composition of gut microbiota and preserving gut epithelial barrier integrity.

https://ift.tt/2LHkNZM

Sex-specific changes in postnatal GH and PRL secretion in somatotrope LEPR-null mice

The developing pituitary is a rapidly changing environment that is constantly meeting the physiological demands of the growing organism. During early postnatal development, the anterior pituitary is refining patterns of anterior hormone secretion in response to numerous genetic factors. Our laboratory previously developed a somatotrope leptin receptor (LEPR) deletion mouse model that had decreased lean body mass, disrupted metabolism, decreased GH stores and was GH deficient as an adult. To understand how deletion of LEPR in somatotropes altered GH, we turned our attention to postnatal development. The current study examines GH, PRL, TSH, ACTH, LH and FSH secretion during postnatal days 4, 5, 8, 10 and 15 and compares age and sex differences. The LEPR mutants have dysregulation of GH (P < 0.03) and a reduced developmental prolactin peak in males (P < 0.04) and females (P < 0.002). There were no differences in weight between groups, and the postnatal leptin surge appeared to be normal. Percentages of immunolabeled GH cells were reduced in mutants compared with controls in all age groups by 35–61% in males and 41–44% in females. In addition, we measured pituitary expression of pituitary transcription factors, POU1F1 and PROP1. POU1F1 was reduced in mutant females at PND 10 (P < 0.009) and PND 15 (P < 0.02) but increased in males at PND 10 (P < 0.01). PROP1 was unchanged in female mutants but showed developmental increases at PND 5 (P < 0.02) and PND 15 (P < 0.01). These studies show that the dysfunction caused by LEPR deletion in somatotropes begins as early as neonatal development and involves developing GH and prolactin cells (somatolactotropes).

https://ift.tt/2M8Y3OR

Is Positioning During Lumbar Puncture Clinically Significant?

No abstract available

https://ift.tt/2ArIm3P

Shared decision-making for postoperative analgesia: A semistructured qualitative study

BACKGROUND Shared decision-making (SDM) and decision-support tools have attracted broad support in healthcare as they improve medical decision-making. Experts disagree on how these can help patients evaluate their present situation and possible outcomes of therapy, and how they might reduce decisional conflict. Little is known about their implementation, especially in anaesthesiology. OBJECTIVE To obtain a more fundamental understanding of pre-operative SDM and evaluate the use of a decision-support tool for postoperative analgesia after major thoracic and abdominal surgery. DESIGN A qualitative study with semistructured, in-depth interviews of patients and professionals. SETTING Patient recruitment took place at the Radboud University Medical Centre in Nijmegen and the Canisius Wilhelmina Hospital in Nijmegen, a nonacademic teaching centre. Professionals of the Radboud University Medical Centre were invited to participate in the interviews. PARTICIPANTS Interviews were performed with 10 individual patients and two focus groups both consisting of eight different professionals. MAIN OUTCOME MEASURES To gain insight into the provision of pre-operative information, decision-making processes and the clarity and usability of a prototype decision-support tool. RESULTS Professionals seemed to provide their patients with information directed towards the application of epidural analgesia, providing little attention to its negative effects. For many patients, the information was not tailored to their needs. Patients' involvement in decision-making was minimal, but they did not feel a need for more involvement. They were positive about the decision-support tool, although they indicated that it would not have influenced their treatment decision. Professionals expressed their doubt about the capacity of their patients to fully understand the decisions involved and about the clinical usability of the decision-support tool, because patients might misinterpret the information provided. CONCLUSION The results of this study suggest that both patients and professionals did not adhere to some 'self-evident' principles of SDM when postoperative analgesia after major thoracic and abdominal surgery was discussed. Correspondence to Dr Martin J.L. Bucx, MD, PhD, Consultant, Anaesthesiologist and Clinical Epidemiologist, Department of Anaesthesiology, Pain and Palliative Medicine, Radboud University Medical Center, Internal Postal Code 717, PO Box 9101, 6500 HB Nijmegen, The Netherlands Tel: +31 24 361 45 53; fax: +31 24 354 04 62; e-mail: Martin.Bucx@Radboudumc.nl Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Website (https://ift.tt/2ylyqmW). © 2018 European Society of Anaesthesiology

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Simple dichotomous assessment of cranial artery inflammation by conventional 18F-FDG PET/CT shows high accuracy for the diagnosis of giant cell arteritis: a case-control study

Abstract

Purpose

To estimate the diagnostic accuracy of conventional 18F-FDG PET/CT of cranial arteries in the diagnosis of giant cell arteritis (GCA).

Methods

The study was a retrospective case-control study. The reference diagnosis was fulfillment of the 1990 ACR criteria for GCA. All patients had new-onset GCA. Conventional 18F-FDG PET/CT was performed before glucocorticoid treatment. Controls were age- and sex-matched patients with a previous history of malignant melanoma (MM) undergoing surveillance PET/CT >6 months after MM resection. PET images were evenly cropped to include only head and neck and were assessed in random order by four nuclear medicine physicians blinded to reference diagnosis. Temporal (TA), maxillary (MA) and vertebral (VA) arteries were visually rated for 18F-FDG uptake. Interreader agreement was evaluated by Fleiss kappa.

Results

A total of 44 patients and 44 controls were identified. In both groups, the mean age was 69 years (p = 0.45) and 25/44 were women. 35/41 GCA patients were temporal artery biopsy positive (TAB). Considering only FDG uptake in TA and/or MA, diagnostic sensitivity and specificity was 64 and 100%. Including VA, sensitivity increased to 82% and specificity remained 100%. Interreader agreement was 91% and Fleiss kappa 0.82 for the PET diagnosis based on the cranial arteries.

Conclusion

Conventional 18F-FDG PET/CT is an accurate and reliable tool to diagnose cranial arteritis in glucocorticoid-naïve GCA patients. The high diagnostic specificity suggests that TAB can be omitted in patients with 18F-FDG uptake in cranial arteries. 18F-FDG PET/CT performed in patients with suspected vasculitis should always include the head and neck.

https://ift.tt/2OuAeCx

Processing number and length in the parietal cortex: sharing resources, not a common code

Publication date: Available online 31 July 2018

Source: Cortex

Author(s): Valentina Borghesani, Maria Dolores de Hevia, Arnaud Viarouge, Pedro Pinheiro Chagas, Evelyn Eger, Manuela Piazza

Abstract

A current intense discussion in numerical cognition concerns the relationship between the processing of numerosity and other non-numerical quantities. In particular, it is a matter of debate whether number and other quantities (e.g. size, length) are represented separately in the brain or whether they share a common generalized magnitude representation. We acquired high-resolution functional MRI data while adult subjects engaged in a magnitude comparison task involving either numerosity (i.e., which of the two sets has more elements?) or line length (i.e., which of the two lines is longer?). We compared the activation evoked by the two different types of quantity and observed a common recruitment of a vast portion of occipital and parietal cortices. Using MVPA, we demonstrated that some of the commonly activated regions represented the discrete and continuous quantities via a similar distance-dependent magnitude code. However, we found no effect of distance across the two quantity representations, failing to support the existence of a common, dimension invariant, generalized quantity code. Taken together, these findings indicate that although the processing of number and length is supported by partially overlapping neural resources, representations within these regions do not appear to be based on a common neural code.

https://ift.tt/2mXiWkU

Cognitive and neural markers of super-recognisers’ face processing superiority and enhanced cross-age effect

Publication date: Available online 31 July 2018

Source: Cortex

Author(s): Elena Belanova, Josh P. Davis, Trevor Thompson

Abstract

Super-recognisers inhabit the extreme high end of an adult face processing ability spectrum in the population. While almost all research in this area has evaluated those with poor or mid-range abilities, evaluating whether super-recognisers' superiority generates distinct electrophysiological brain activity, and transcends to different age group faces (i.e., children's) is important for enhancing theoretical understanding of normal and impaired face processing. It may also be crucial for policing, as super-recognisers may be deployed to operations involving child identification and protection. In Experiment 1, super-recognisers (n = 315) outperformed controls (n = 499) at adult and infant face recognition, while also displaying larger cross-age effects. These findings were replicated in Experiment 2 (super-recognisers, n = 19; controls, n = 28), although one SR with frequent infant exposure showed no cross-age effect. Compared to controls, super-recognisers also generated significantly greater electrophysiological activity in event-related potentials associated with pictorial processing (P1) and explicit recognition (P600). Experiment 3, employing an upright and inverted sequential matching design found super-recognisers (n = 24) outperformed controls (n = 20) at adult and infant face matching, but showed no upright cross-age matching effects. Instead, they displayed larger inversion effects, and cross-age inversion effects, implicating the role of holistic processing in their perceptual superiority. Larger cross-age effects in recognition, but not matching suggests that super-recognisers' adult face recognition is partly driven by experience. However, their enhanced infant face recognition suggest super-recognisers' superiority is also experience-independent, results that have implications for policing and for models of face recognition.

https://ift.tt/2M5tCZF

Arithmetic learning modifies the functional connectivity of the fronto-parietal network

Publication date: Available online 31 July 2018

Source: Cortex

Author(s): Hui Zhao, Xiaoxi Li, Vyacheslav Karolis, Yi Feng, Haijing Niu, Brian Butterworth

Abstract

How Resting-State Functional Connectivity (RSFC) is modified by learning is an important but rarely asked question. Here we used functional near-infrared spectroscopy (fNIRS) to measure changes in RSFC after learning novel subtraction and multiplication facts by forty-one young adult volunteers. We also measured changes in regional hemoglobin concentration. Fronto-parietal RSFC was modified by arithmetic learning and the fronto-parietal RSFC configuration before learning predicted the effectiveness of arithmetic learning. We also found a significant learning effect indicated by a monotonic decrease in reaction time and an increase in accuracy. Regional task-dependent oxy-hemoglobin concentration differentiated subtraction from multiplication learning supporting previous fMRI findings. These results suggest the sensitivity and importance of fronto-parietal connectivity to arithmetic learning.

https://ift.tt/2mXvicI

The cerebellar topography of attention sub-components in spinocerebellar ataxia type 2

Publication date: Available online 31 July 2018

Source: Cortex

Author(s): M. Lupo, G. Olivito, C. Iacobacci, S. Clausi, S. Romano, M. Masciullo, M. Molinari, M. Cercignani, M. Bozzali, M. Leggio

Abstract

Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant neurodegenerative disease characterized by a progressive cerebellar syndrome and multiple-domain cognitive impairments. The cerebellum is known to contribute to distinct functional networks related to higher-level functions. The aims of the present study were to investigate the different sub-components of attention and to analyse possible correlations between attention deficits and specific cerebellar regions in SCA2 patients.

To this purpose, 11 SCA2 patients underwent an exhaustive attention battery that evaluated several attention sub-components. The SCA2 group performed below the normal range in tasks assessing selective attention, divided attention, and sustained attention, obtaining negative Z-scores. These results were confirmed by non-parametric Mann-Whitney U tests that showed significant differences between SCA2 and control subjects in the same sub-components of the attention battery, allowing us to speculate on cerebellar involvement when a high cognitive demand is required (i.e., multisensory integration, sequencing, prediction of events, and inhibition of inappropriate response behaviours).

The voxel-based morphometry analysis showed a pattern of significantly reduced grey matter volume in specific cerebellar lobules. In particular, the SCA2 patients showed significant grey matter loss in bilateral regions of the anterior cerebellar hemisphere (I-V) and in the posterior lobe (VI-IX) and posterior vermis (VI-IX).

Statistical analysis found significant correlations between grey matter reductions in the VIIb/VIIIa cerebellar lobules and impairments in Sustained and Divided Attention tasks and between grey matter reduction in the vermal VI lobule and impairment in the Go/NoGo task.

For the first time, the study demonstrated the involvement of specific cerebellar lobules in different sub-components of the attention domain, giving further support to the inclusion of the cerebellum within the attention network.

https://ift.tt/2KdHPBV

Neural signatures of inhibitory control in bilingual spoken production

Publication date: Available online 31 July 2018

Source: Cortex

Author(s): Eleonora Rossi, Sharlene Newman, Judith F. Kroll, Michele Diaz

Abstract

Bilinguals activate both languages when they intend to speak even one language alone (e.g., Kroll et al., 2006). At the same time, they are able to select the language they intend to speak and switch back and forth between languages rapidly, with few production errors. Previous research utilizing behavioral (Linck et al., 2009) and neuroimaging techniques (ERPs and fMRI; Guo et al., 2011; Misra et al., 2012) suggest that successful bilingual speech production is enabled by active inhibition of the language not in use. Results showing an asymmetric switching cost for the L1 compared to the L2 (with a larger cost -reflected in longer naming latencies-when switching from the L2 to the L1) have been taken as evidence that the L1 (usually the dominant language for bilinguals who learned their second language later in life) may need to be inhibited when speaking in the L2. However, there is still little research on the scope of this inhibitory process. The goal of this event-related functional magnetic resonance imaging study is to understand how the recruitment of neural areas implicated during bilingual language processing are shaped by the scope of language use. The results show that bilinguals engage a wide functional control network that is hierarchically engaged in local control for single lexical items, but extends further to the broader semantic level, and finally to the whole language. This functional network is modulated by proficiency in the L2.

https://ift.tt/2LHgii7