Transcriptomic changes in the ovaries of scallop Chlamys farreri exposed to benzo[a]pyrene

Abstract

In this study, digital gene expression (DGE) sequencing technology was used to identify alterations in gene transcription of the ovarian tissue of Chlamys farreri (C. farreri) exposed to benzo[a]pyrene (BaP) pollutants. A total of 124 genes were detected differentially expressed with 42 up-regulated and 82 down-regulated genes in BaP DGE libraries. Gene ontology annotation and kyoto encyclopedia of genes and genomes pathway analyses were performed on all genes to elucidate their biological functions and processes. The results showed that numerous enriched differentially expressed genes related to "detoxification process", "damage effects to extracellular matrix and cell interactions", "endocrine disrupting effects" and "tissue damage responses". Quantitative RT-PCR procedure was executed to understand the expression patterns of several important reproductive-related genes. To supplement the reproductive toxicity of BaP, histological analysis of the ovaries illustrated that after 21 days higher dose of BaP exposure, the immature oocytes and degenerated oocytes increased. The study aims to provide reference data for future study of organic pollutions in aquatic mollusks.

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Attentional guidance by relative features: Behavioral and electrophysiological evidence

Abstract

Our ability to select task-relevant information from cluttered visual environments is widely believed to be due to our ability to tune attention to the particular elementary feature values of a sought-after target (e.g., red, orange, yellow). By contrast, recent findings showed that attention is often tuned to feature relationships, that is, features that the target has relative to irrelevant features in the context (e.g., redder, yellower). However, the evidence for such a relational account is so far exclusively based on behavioral measures that do not allow a safe inference about early perceptual processes. The present study provides a critical test of the relational account, by measuring an electrophysiological marker in the EEG of participants (N2pc) in response to briefly presented distractors (cues) that could either match the physical features of the target or its relative features. In a first experiment, the target color and nontarget color were kept constant across trials. In line with a relational account, we found that only cues with the same relative color as the target were attended, regardless of whether the cues had the same physical color as the target. In a second experiment, we demonstrate that attention is biased to the exact target feature value when the target is embedded in a randomly varying context. Taken together, these results provide the first electrophysiological evidence that attention can modulate early perceptual processes differently; in a context-dependent manner versus a context-independent manner, resulting in marked differences in the range of colors that can attract attention.

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Emotional responses to irony and emoticons in written language: Evidence from EDA and facial EMG

Abstract

While the basic nature of irony is saying one thing and communicating the opposite, it may also serve additional social and emotional functions, such as projecting humor or anger. Emoticons often accompany irony in computer-mediated communication, and have been suggested to increase enjoyment of communication. In the current study, we aimed to examine online emotional responses to ironic versus literal comments, and the influence of emoticons on this process. Participants read stories with a final comment that was either ironic or literal, praising or critical, and with or without an emoticon. We used psychophysiological measures to capture immediate emotional responses: electrodermal activity to directly measure arousal and facial electromyography to detect muscle movements indicative of emotional expressions. Results showed higher arousal, reduced frowning, and enhanced smiling for messages with rather than without an emoticon, suggesting that emoticons increase positive emotions. A tendency toward less negative responses (i.e., reduced frowning and enhanced smiling) for ironic than literal criticism, and less positive responses (i.e., enhanced frowning and reduced smiling) for ironic than literal praise suggests that irony weakens the emotional impact of a message. The present findings indicate the utility of a psychophysiological approach in studying online emotional responses to written language.

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Clinical and echocardiographic outcomes after bariatric surgery in obese patients with left ventricular systolic dysfunction

Circulation: Heart Failure

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Effectiveness of anti-TNF? drugs in patients with Crohn's disease who do not achieve remission with their first anti-TNF? agent

Digestive and Liver Diseases

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Bundled payments for surgical colectomy among medicare enrollees

JAMA Surgery

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Bevacizumab combined with docetaxel, oxaliplatin, and capecitabine, followed by maintenance with capecitabine and bevacizumab, as first-line treatment of patients with advanced HER2-negative gastric cancer: A multicenter phase 2 study

Cancer

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Burden of rotavirus disease in Norway: using national registries for public health research

The Pediatric Infectious Disease Journal

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Sofosbuvir/velpatasvir improves patient-reported outcomes in HCV patients: Results from astral-1 placebo-controlled trial

Journal of Hepatology

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Effect of Kuijie granule on the expression of TGF-β/Smads signaling pathway in patients with ulcerative colitis

Evidence-based Complementary and Alternative Medicine

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Presence of hepatitis C (HCV) infection in baby boomers with medicare is independently associated with mortality and resource utilisation

Alimentary Pharmacology and Therapeutics

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Impaired outcome colitis associated rectal cancer versus sporadic

Journal of Surgical Research

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Combining routine markers improves the accuracy of transient elastography for hepatitis B cirrhosis detection

Digestive and Liver Diseases

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Decrease in seroma rate after adopting progressive tension sutures without drains: a single surgery center experience of 451 abdominoplasties over 7 years

Aesthetic Surgery Journal

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Responder interferon lambda genotypes are associated with higher risk of liver fibrosis in HIV-hepatitis C virus co-infection

The Journal of Infectious Diseases

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Expression of chemokine receptor CCR7 is a negative prognostic factor for patients with gastric cancer: A meta-analysis

Gastric Cancer

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The ability of hepascore to predict liver fibrosis in chronic liver disease: a meta-analysis

Liver International

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Contribution of alcoholic and non-alcoholic fatty liver disease to the burden of liver-related morbidity and mortality

Gastroenterology

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Hepatocellular carcinoma detected by regular surveillance: Does timely confirmation of diagnosis matter?

Digestive and Liver Diseases

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Laparoscopic revision of Roux-en-Y gastric bypass to sleeve gastrectomy: A ray of hope for failed Roux-en-Y gastric bypass

Asian Journal of Endoscopic Surgery

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Cost effectiveness and clinical efficacy of biliary stents in patients undergoing neoadjuvant therapy for pancreatic adenocarcinoma in a randomized controlled trial

Gastrointestinal Endoscopy

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The Ecdysone and Notch Pathways Synergistically Regulate Cut at the Dorsal-Ventral Boundary in Drosophila Wing Discs

Publication date: Available online 17 March 2016
Source:Journal of Genetics and Genomics
Author(s): Dongyu Jia, Jamal Bryant, Allison Jevitt, Gabriel Calvin, Wu-Min Deng
Metazoan development requires coordination of signaling pathways to regulate patterns of gene expression. In Drosophila, the wing imaginal disc provides an excellent model for the study of how signaling pathways interact to regulate pattern formation. The determination of the dorsal/ventral (DV) boundary of the wing disc depends on the Notch pathway, which is activated along the DV boundary and induces the expression of the homeobox transcription factor, Cut. Here, we show that Broad (Br), a zinc-finger transcription factor, is also involved in regulating Cut expression in the DV boundary region. However, Br expression is not regulated by Notch signaling in wing discs, rather, ecdysone signaling is the upstream signal that induces Br for Cut upregulation. Also, we find that the ecdysone-Br cascade upregulates cut-lacZ expression, a reporter containing a 2.7 kb cut enhancer region, implying that ecdysone signaling, similar to Notch, regulates cut at the transcriptional level. Collectively, our findings reveal that the Notch and ecdysone signaling pathways synergistically regulate Cut expression for proper DV boundary formation in the wing disc. Additionally, we show br promotes Delta, a Notch ligand, near the DV boundary to suppress aberrant high Notch activity, indicating further interaction between the two pathways for DV patterning of the wing disc.



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Lessons from nature: Signaling cascades associated with vertebrate brain anoxic survival

Mammalian neurons undergo rapid degeneration when oxygen supply is curtailed. Neuroprotective pathways are induced during hypoxia/ischemia but their analysis is complicated by concurrent pathological events. Survival mechanisms can be investigated in anoxia tolerant freshwater turtle species, which survive oxygen deprivation and post-anoxic reoxygenation by entrance into a state of reversible hypometabolism. Many energy demanding processes are suppressed, including ion flux and neurotransmitter release, while cellular and protective mechanisms including certain MAP Kinases are upregulated. This superfamily of serine/threonine kinases plays a significant role in vital cellular processes including cell proliferation, differentiation, stress adaptation, and apoptosis in response to external stimuli. Here we report that neuronal survival relies on robust coordination between the major signaling cascades: upregulation of the pro-survival Akt and ERK1/2 and suppression of the p38MAPK and JNK pathways. Other protective responses, including the upregulation of heat shock proteins (HSPs) and antioxidants, allow the turtle brain to abrogate potential oxidative stress upon reoxygenation.

This article is protected by copyright. All rights reserved

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ER stress inhibition improves coronary artery function in type 2 diabetic mice

Aim: Vascular dysfunction is a major complication in type 2 diabetes. Although endoplasmic reticulum (ER) stress has been suggested to be a contributing factor in cardiovascular diseases, the relationship between ER stress and vascular dysfunction in type 2 diabetes remains unclear. Thus, in the present study, we examined whether ER stress contributes coronary artery dysfunction and ER stress inhibition ameliorates vascular function in type 2 diabetes. Methods: Type 2 diabetic and their control mice were treated with or without ER stress inhibitor (taurine-conjugated ursodeoxycholic acid, TUDCA, 150 mg kg⁻¹ day⁻¹, intra-peritoneal injection for two weeks) for 2 weeks. Myogenic response and endothelium-dependent relaxation were measured in the pressurized coronary arteries. Results In type 2 diabetic mice, blood glucose, and body weight are elevated compared to control mice. The myogenic response is potentiated and endothelium-dependent relaxation is impaired in the coronary arteries from type 2 diabetic mice. Interestingly, treatment of ER stress inhibitor normalized myogenic responses and endothelium-dependent relaxation. These data were associated with an increase in ER stress marker expression or phosphorylation (IRE1-XBP-1, and PERK-eIF2α) in type 2 diabetic mice, which were reduced by treatment with ER stress inhibitor. Conclusion: ER stress inhibition normalizes myogenic response and improves vascular function in type 2 diabetes. Therefore, ER stress could be a potential target for cardiovascular diseases in diabetes mellitus.

This article is protected by copyright. All rights reserved

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Spanish Translated Abstracts

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Academy News

As the primary medical society for the specialty of PM&R, your Academy is focused on moving the specialty and you forward. Academy membership supports initiatives to assist our members with:

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A Study on Rumen Foreign Body Impaction in sheep slaughtered at the Maiduguri Metropolitan abattoir, Maiduguri, Nigeria

2016-03-17T00-44-39Z
Source: International Journal of Livestock Research
Diana Anjili Bwala, Innocent Damudu Peter, Chinedu Athanasius Eze, Yachilla Maryam Bukar-Kolo, Muhammad Modu Bukar.
This study was conducted on sheep slaughtered at the Maiduguri Metropolitan Council abattoir with the objective of determining the histopathology of the rumen with foreign body impaction. A total of 91 sheep (63 males and 28 females) were selected using simple random sampling. Out of the total number, 15 (16.5%) were found to have foreign bodies, of which 13 (86.7%) were females while 2 (13.3%) were males. The Foreign bodies identified were an admixture of polythene, plastic materials (shopping bags, mats and ropes) and pieces of wood. Breed distribution of the foreign body impaction showed that the highest percentage was recorded in crossbreeds (20%) while the lowest was in Uda breed (8.3%). It was demonstrated that rumen with Foreign Body Impaction was characterized by increased keratinisation of the mucosal epithelium. The associated keratinisation of the rumen epithelium and the expected deleterious effects on rumen nutrient uptake might exacerbate further, the problems of shortage and low quality of feed in the arid Sahel region where Maiduguri is situated. This information is important for clinicians for management of FBI in ewes.


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The obese patient undergoing nonbariatric surgery.

Purpose of review: This article provides the reader with recent findings on the pathophysiology of comorbidities in the obese, as well as evidence-based treatment options to deal with perioperative respiratory challenges. Recent findings: Our understanding of obesity-associated asthma, obstructive sleep apnea, and obesity hypoventilation syndrome is still expanding. Routine screening for obstructive sleep apnea using the STOP-Bang score might identify high-risk patients that benefit from perioperative continuous positive airway pressure and close postoperative monitoring. Measures to most effectively support respiratory function during induction of and emergence from anesthesia include optimal patient positioning and use of noninvasive positive pressure ventilation. Appropriate mechanical ventilation settings are under investigation, so that only the use of protective low tidal volumes could be currently recommended. A multimodal approach consisting of adjuvants, as well as regional anesthesia/analgesia techniques reduces the need for systemic opioids and related respiratory complications. Summary: Anesthesia of obese patients for nonbariatric surgical procedures requires knowledge of typical comorbidities and their respective treatment options. Apart from cardiovascular diseases associated with the metabolic syndrome, awareness of any pulmonary dysfunction is of paramount. A multimodal analgesia approach may be useful to reduce postoperative pulmonary complications. Copyright (C) 2016 YEAR Wolters Kluwer Health, Inc. All rights reserved.

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A Comparison of the Haider Tube-Guard(R) Endotracheal Tube Holder Versus Adhesive Tape to Determine if This Novel Device Can Reduce Endotracheal Tube Movement and Prevent Unplanned Extubation.

BACKGROUND: Endotracheal tube security is a critical safety issue. We compared the mobility of an in situ endotracheal tube secured with adhesive tape to the one secured with a new commercially available purpose-designed endotracheal tube-holder device (Haider Tube-Guard(R)). We also observed for the incidence of oropharyngeal or facial trauma associated with the 2 tube fixation methods. METHODS: Thirty adult patients undergoing general anesthesia with neuromuscular blockade were prospectively enrolled. Immediately after intubation, a single study author positioned the endotracheal tube tip in the distal trachea using a bronchoscope. Anesthesiologists caring for patients secured the tube in their normal fashion (always with adhesive tape). A force transducer was used to apply linear force, increasing to 15 N or until the principal investigator deemed that the force be aborted for safety reasons. The displacement of the endotracheal tube was measured with the bronchoscope. Any tape was then removed and the endotracheal tube secured with the Haider Tube-Guard device. The linear force was reapplied and the displacement of the endotracheal tube measured. The Haider Tube-Guard device was left in place for the duration of the case. The patient's face and oropharynx were examined for any evidence of trauma during surgery and in the recovery room. On discharge from the postanesthesia care unit, the patient answered a brief survey assessing for any subjective evidence of minor facial or oropharyngeal trauma. RESULTS: Under standardized tension, the endotracheal tube withdrew a mean distance of 3.4 cm when secured with adhesive tape versus 0.3 cm when secured with the Haider Tube-Guard (P 1 cm) when adhesive tape was used to secure the tube versus 3% (1/30) when the Haider Tube-Guard was used (P 4 cm) when the endotracheal tube was secured with tape versus 0% (0/30) when secured with the Haider Tube-Guard (P = 0.004). Six patients with taped endotracheal tubes required the traction to be aborted before 15 N of force was achieved to prevent potential extubation as the tape either separated from the face or stretched to allow excessive endotracheal tube movement. None of the patients appeared to sustain any injury from the Haider Tube-Guard device. CONCLUSIONS: The Haider Tube-Guard significantly reduced the mobility of the endotracheal tube when compared with adhesive tape and was well tolerated in our observations. This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially. (C) 2016 International Anesthesia Research Society

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Anesthetic Care in Mozambique.

BACKGROUND: The World Bank and Lancet Commission in 2015 have prioritized surgery in Low-Income Countries (LIC) and Lower-Middle Income Countries (LMICs). This is consistent with the shift in the global burden of disease from communicable to noncommunicable diseases over the past 20 years. Essential surgery must be performed safely, with adequate anesthesia monitoring and intervention. Unfortunately, a huge barrier to providing safe surgery includes the paucity of an anesthesia workforce.1 In this study, we qualitatively evaluated the anesthesia capacity of Mozambique, a LIC in Africa with limited access to anesthesia and safe surgical care. Country-based solutions are suggested that can expand to other LIC and LMICs. METHODS: A comprehensive review of the Mozambique anesthesia system was conducted through interviews with personnel in the Ministry of Health (MOH), a school of medicine, a public central referral hospital, a general first referral hospital, a private care hospital, and leaders in the physician anesthesia community. Personnel databases were acquired from the MOH and Maputo Central Hospital. RESULTS: Quantitative results reveal minimal anesthesia capacity (290 anesthesia providers for a population of >25 million or 0.01:10,000). The majority of physician anesthesiologists practice in urban settings, and many work in the private sector. There is minimal capacity for growth given only 1 Mozambique anesthesia residency with inadequate resources. The most commonly perceived barriers to safe anesthesia in this critical shortage are lack of teachers, lack of medical student interest in and exposure to anesthesia, need for more schools, low allocation to anesthesia from the list of available specialist prospects by MOH, and low public payments to anesthesiologists. Qualitative results show assets of a good health system design, a supportive environment for learning in the residency, improvement in anesthetic care in past decades, and a desire for more educational opportunities and teachers. CONCLUSIONS: Mozambique has a strong health system design but few resources for surgery and safe anesthesia. At present, similar to other LICs, human resources, access to essential medicines, and safety monitoring limit safe anesthesia in Mozambique. (C) 2016 International Anesthesia Research Society

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Prothrombin Complex Concentrates for Bleeding in the Perioperative Setting.

Prothrombin complex concentrates (PCCs) contain vitamin K-dependent clotting factors (II, VII, IX, and X) and are marketed as 3 or 4 factor-PCC formulations depending on the concentrations of factor VII. PCCs rapidly restore deficient coagulation factor concentrations to achieve hemostasis, but like with all procoagulants, the effect is balanced against thromboembolic risk. The latter is dependent on both the dose of PCCs and the individual patient prothrombotic predisposition. PCCs are approved by the US Food and Drug Administration for the reversal of vitamin K antagonists in the setting of coagulopathy or bleeding and, therefore, can be administered when urgent surgery is required in patients taking warfarin. However, there is growing experience with the off-label use of PCCs to treat patients with surgical coagulopathic bleeding. Despite their increasing use, there are limited prospective data related to the safety, efficacy, and dosing of PCCs for this indication. PCC administration in the perioperative setting may be tailored to the individual patient based on the laboratory and clinical variables, including point-of-care coagulation testing, to balance hemostatic benefits while minimizing the prothrombotic risk. Importantly, in patients with perioperative bleeding, other considerations should include treating additional sources of coagulopathy such as hypofibrinogenemia, thrombocytopenia, and platelet disorders or surgical sources of bleeding. Thromboembolic risk from excessive PCC dosing may be present well into the postoperative period after hemostasis is achieved owing to the relatively long half-life of prothrombin (factor II, 60-72 hours). The integration of PCCs into comprehensive perioperative coagulation treatment algorithms for refractory bleeding is increasingly reported, but further studies are needed to better evaluate the safe and effective administration of these factor concentrates. (C) 2016 International Anesthesia Research Society

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Lumbar Epidural Hematoma Following Interlaminar Fluoroscopically Guided Epidural Steroid Injection.

Objective: Spinal epidural steroid injections are generally considered a safe, effective treatment for radicular pain in a variety of spinal conditions. Complications secondary to these injections, although rare, can result in devastating neurologic symptoms. Patients with preexisting moderate-to-severe spinal stenosis and recent use of chronic anticoagulation pose a challenging dilemma when making treatment decisions, as a history of both can increase the risk of complications. Case Report: The following case study provides a description of a patient with spinal stenosis who discontinued anticoagulation therapy according to the recommended guidelines but who experienced a subsequent acute epidural hematoma and significant neurologic injury. Conclusions: This case report describes the potential risk factors present in this patient. Presence of spinal stenosis and the interlaminar approach seem to be significant risk factors in this case. Presence of an intrinsic coagulopathy was not determined. Copyright (C) 2016 by American Society of Regional Anesthesia and Pain Medicine.

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Impact of Type of Needle on Incidence of Intravascular Injection During Diagnostic Lumbar Medial Branch Block.

Background and Objectives: Intravascular (IV) injection of local anesthetics is a potential cause of false-negative results after lumbar medial branch nerve blockade (L-MBB) performed to diagnose facetogenic back pain. The aim of the present study was to identify the relationship between the needle type and the incidence of IV injection in patients undergoing L-MBB using fluoroscopy with digital subtraction imaging (DSI). Methods: In this prospective randomized study, we compared the incidence of IV uptake of contrast medium using the Quincke needle and Whitacre needle under real-time DSI during L-MBB. Clinical and demographic factors associated with the occurrence of IV uptake were also investigated. Results: In total, 126 patients were randomized into the Quincke needle group (n = 62) and Whitacre needle group (n = 64). Intravascular uptake of contrast medium was observed in 66 (9.8%) of 671 L-MBB procedures under DSI. The incidence of IV uptake was 13.9% (47/338) using the Quincke needle and 5.7% (19/333) using the Whitacre needle. In the multivariate generalized estimating equations analysis, use of a Quincke needle was related to positive IV injection at a 1.898-fold higher rate than was use of a Whitacre needle (95% confidence interval, 1.025-3.516) and a positive aspiration test predicted IV injection at a 21.735-fold higher rate (95% confidence interval, 11.996-52.258). Conclusions: Lumbar medial branch nerve blockade using the Quincke needle was associated with a 1.9-fold higher rate of IV injection than was L-MBB using the Whitacre needle under DSI. Although further study is needed to confirm the clinical efficacy, Whitacre needles can be considered to reduce the risk of IV injection during L-MBB. Copyright (C) 2016 by American Society of Regional Anesthesia and Pain Medicine.

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In vivo analysis of cerebellar Purkinje cell activity in SCA2 transgenic mouse model

Cerebellar Purkinje cells (PCs) are primarily affected in many spinocerebellar ataxias (SCA). In this study we investigated functional activity of PCs in transgenic mouse model of SCA2, a polyglutamine neurodegenerative hereditary disorder. In our studies we used extracellular single-unit recording method to compare spontaneous activity of PCs in age-matched wild type mice and SCA2-58Q transgenic mice. We discovered that the fraction of PCs with bursting and irregular pattern of spontaneous activity dramatically increases in aged SCA2-58Q mice when compared with wild type littermates. Small conductance calcium-activated potassium (SK) channels play an important role in determining firing rate of PCs. Indeed, we demonstrated that intraperitoneal (i.p.) injection of SK channel inhibitor NS8593 induces irregular pattern of PC activity in wild type mice. Furthermore, we demonstrated that i.p. injection of SK channel positive modulator chlorzoxazone (CHZ) decreases spontaneous firing rate of cerebellar PCs. Finally, we have shown that i.p. injections with CHZ normalize firing activity of cerebellar PCs from aging SCA2-58Q mice. We propose that alterations in PC firing patterns is one of potential causes of ataxic symptoms in SCA2 and in other SCAs and that positive modulators of SK channels can be used to normalize activity of PCs and alleviate ataxic phenotype in SCA patients.

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Metaplasticity in human primary somatosensory cortex: effects on physiology and tactile perception

Theta-burst stimulation (TBS) over human primary motor cortex evokes plasticity and metaplasticity, the latter contributing to the homeostatic balance of excitation and inhibition. Our knowledge of TBS-induced effects on primary somatosensory cortex (SI) is limited, and it is unknown whether TBS induces metaplasticity within human SI. Sixteen right-handed participants (6 females, mean age 23 years) received two TBS protocols (cTBS and iTBS) delivered in six different combinations over SI in separate sessions. TBS protocols were delivered at 30 Hz and were as follows: a single cTBS protocol, a single iTBS protocol, cTBS followed by cTBS, iTBS followed by iTBS, cTBS followed by iTBS and iTBS followed by cTBS. Measures included the amplitudes of the first and second somatosensory evoked potentials (SEPs) via median nerve stimulation, their paired-pulse ratio (PPR), and temporal order judgment (TOJ). Dependent measures were obtained prior to TBS and at 5, 25, 50 and 90 minutes following stimulation. Results indicate similar effects following cTBS and iTBS; increased amplitudes of the second SEP and PPR without amplitude changes to SEP 1, and impairments in TOJ. Metaplasticity was observed such that TOJ impairments following a single cTBS protocol were abolished following consecutive cTBS protocols. Additionally, consecutive iTBS protocols altered the time course of effects when compared to a single iTBS protocol. In conclusion, 30 Hz cTBS and iTBS protocols delivered in isolation induce effects consistent with a TBS-induced reduction in intracortical inhibition within SI. Further, cTBS and iTBS-induced metaplasticity appear to follow homeostatic and non-homeostatic rules, respectively.

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Muscle fatigue increases beta-band coherence between the firing times of simultaneously active motor units in the first dorsal interosseous muscle

Synchronization between the firing times of simultaneously active motor units (MUs) is generally assumed to increase during fatiguing contractions. To date, however, estimates of MU synchronization have relied on indirect measures, derived from surface electromyographic (EMG) interference signals. This study used intramuscular coherence to investigate the correlation between MU discharges in the first dorsal interosseous muscle during and immediately following a submaximal fatiguing contraction, and after rest. Coherence between composite MU spike trains, derived from decomposed surface EMG, were examined in the delta (1-4 Hz), alpha (8-12 Hz), beta (15-30 Hz) and gamma (30-60 Hz) band frequency ranges. A significant increase in MU coherence was observed in the delta, alpha and beta frequency bands postfatigue. In addition, wavelet coherence revealed a tendency for delta, alpha and beta-band coherence to increase during the fatiguing contraction, with subjects exhibiting low initial coherence values displaying the greatest relative increase. This was accompanied by an increase in MU short-term synchronization and a decline in mean firing rate of the majority of MUs detected during the sustained contraction. A model of the motoneuron pool and surface EMG was used to investigate factors influencing the coherence estimate. Simulation results indicated that changes in motoneuron inhibition and firing rates alone could not directly account for increased beta-band coherence postfatigue. The observed increase is, therefore, more likely to arise from an increase in the strength of correlated inputs to MUs as the muscle fatigues.

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Network Burst Activity in Hippocampal Neuronal Cultures: The Role of Synaptic and Intrinsic Currents

The goal of this work is to define the contributions of intrinsic and synaptic mechanisms towards spontaneous network-wide bursting activity, observed in dissociated rat hippocampal cell cultures. This network behavior is typically characterized by short-duration bursts, separated by order of magnitude longer interburst intervals. We hypothesize that while short-timescale synaptic processes modulate spectro-temporal intraburst properties and network-wide burst propagation, much longer-timescales of intrinsic membrane properties such as persistent-sodium (Nap) currents, govern burst onset during interburst intervals. To test this, we used synaptic receptor antagonists PTX, CNQX and CPP to selectively block GABA_A, AMPA and NMDA receptors and riluzole to selectively block Na_p channels. We systematically compared intracellular activity (recorded using patch-clamp) and network-activity (recorded using multi-electrode arrays), in eight different synaptic-connectivity conditions: GABA_A+NMDA+AMPA, NMDA+AMPA, GABA_A+AMPA, GABA_A+NMDA, AMPA, NMDA, GABA_A, and all receptors blocked. Furthermore, we used mixed-effects modeling to quantify aforementioned independent and interactive synaptic-receptor contributions towards spectro-temporal burst properties including intraburst spike-rate, burst-activity index, burst duration, power in the local field potential, network connectivity and transmission delays. We found that blocking intrinsic Nap currents completely abolished bursting activity, demonstrating their critical role in burst onset within the network. On the other hand, blocking different combinations of synaptic receptors revealed that spectro-temporal burst properties are uniquely associated with synaptic functionality and that excitatory connectivity is necessary for presence of network-wide bursting. In addition to confirming the critical contribution of direct excitatory effects, mixed-effects modeling also revealed distinct combined (nonlinear) contributions of excitatory and inhibitory synaptic activity to network-bursting properties.

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Retinal crosstalk in the mammalian visual system

The existence and functional relevance of efferent optic nerve fibers in mammals has long been debated. While anatomical evidence for cortico-retinal and retino-retinal projections is substantial, physiological evidence is lacking as efferent fibers are few in number and severed in studies of excised retinal tissue. Here we show that interocular connections contribute to retinal bioelectrical activity in adult mammals. Full-field flash electroretinograms (ERGs) were recorded from one or both eyes of Brown-Norway rats under dark-adapted (n=16) and light-adapted (n=11) conditions. Flashes were confined to each eye by an opaque tube that blocked stray light. Monocular flashes evoked a small (5-15μV) signal in the non-illuminated eye, which was named "crossed ERG" (xERG). The xERG began under dark-adapted conditions with a positive (xP1) wave that peaked at 70-90ms and ended with slower negative (xN1) and positive (xP2) waves from 200-400ms. xN1 was absent under light-adapted conditions. Injection of tetrodotoxin in either eye (n=15) eliminated the xERG. Intraocular pressure elevation of the illuminated eye (n=6) had the same effect. The treatments also altered the ERG b-wave in both eyes, and the alterations correlated with xERG disappearance. Optic nerve stimulation (n=3) elicited a biphasic compound action potential in the non-stimulated nerve with 10-13ms latency, implying the xERG comes from slow-conducting (W-type) fibers. Monocular dye application (n=7) confirmed the presence of retino-retinal ganglion cells in adult rats. We conclude that mammalian eyes communicate directly with each other via a handful of optic nerve fibers. The crosstalk alters retinal activity in rats, and perhaps other animals.

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Local and global contributions to hemodynamic activity in mouse cortex

Imaging techniques such as fMRI seek to estimate neural signals in local brain regions through measurements of hemodynamic activity. However, hemodynamic activity is accompanied by large vascular fluctuations of unclear significance. To characterize these fluctuations and their impact on estimates of neural signals, we used optical imaging in visual cortex of awake mice. We found that hemodynamic activity can be expressed as the sum of two components, one local and one global. The local component reflected presumed neural signals driven by visual stimuli in the appropriate retinotopic region. The global component constituted large fluctuations shared by larger cortical regions, which extend beyond visual cortex. These fluctuations varied from trial to trial, but they did not constitute noise: they correlated with pupil diameter, suggesting that they reflect variations in arousal or alertness. Distinguishing local and global contributions to hemodynamic activity may help understand neurovascular coupling and interpret measurements of hemodynamic responses.

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Reactivation of visual-evoked activity in human cortical networks

In the absence of sensory input, neuronal networks are far from being silent. Whether spontaneous changes in ongoing activity reflect previous sensory experience or stochastic fluctuations in brain activity is not well understood. Here we demonstrate reactivation of stimulus-evoked activity that is distributed across large areas in the human brain. We performed simultaneous electrocorticography recordings from occipital, parietal, temporal, and frontal areas in awake humans in the presence and absence of sensory stimulation. We found that, in the absence of visual input, repeated exposure to brief natural movies induces robust stimulus-specific reactivation at individual recording sites. The reactivation sites were characterized by greater global connectivity compared to those sites that did not exhibit reactivation. Our results indicate a surprising degree of short-term plasticity across multiple networks in the human brain as a result of repeated exposure to unattended information.

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Nitric oxide/ cGMP/ PKG signaling pathway activated by M1-type muscarinic acetylcholine receptor cascade inhibits Na+-activated K+ currents in Kenyon cells

The interneurons of the mushroom body, known as Kenyon cells, are essential for the long-term memory of olfactory associative learning in some insects. Some studies have reported that nitric oxide (NO) is strongly related to this long-term memory in Kenyon cells. However, the target molecules and upstream and downstream NO signaling cascades are not completely understood. Here, we analyzed the effect of the NO signaling cascade on Na⁺-activated K⁺ (K_Na) channel activity in Kenyon cells of crickets (Gryllus bimaculatus). We found that two different NO donors, S-nitrosoglutatione (GSNO) and S-nitroso-N-acetyl-DL-penicillamine (SNAP), strongly suppressed K_Na channel currents. Additionally, this inhibitory effect of GSNO on K_Na channel activity was diminished by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), an inhibitor of soluble guanylate cyclase (sGC), and KT5823, an inhibitor of protein kinase G (PKG). Next, we analyzed the role of ACh in the NO signaling cascade. ACh strongly suppressed K_Na channel currents, similar to NO donors. Furthermore, this inhibitory effect of ACh was blocked by pirenzepine, an M₁ muscarinic ACh receptor antagonist, but not by 4-DAMP and mecamylamine, an M₃ muscarinic ACh receptor antagonist and a nicotinic ACh receptor antagonist, respectively. The ACh-induced inhibition of K_Na channel currents was also diminished by PLC inhibitor, U73122, and calmodulin antagonist, W-7. Finally, we found that ACh inhibition was blocked by the NO synthase (NOS) inhibitor L-NAME. These results suggested that the ACh signaling cascade promotes NO production by activating NOS, and NO inhibits K_Na channel currents via the sGC/cGMP/PKG signaling cascade in Kenyon cells.

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Developing the Pediatric Gastrointestinal Endoscopy Unit - A Clinical Report by the Endoscopy and Procedures Committee.

No abstract available

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Gut Microbiota Differences in Children from Distinct Socioeconomic Levels Living in the Same Urban Area in Brazil.

Objective: To compare gut microbiota in impoverished children versus children of high socioeconomic status living in the same urban area in Brazil. Methods: A cross-sectional study was conducted to evaluate 100 children living in a slum and 30 children from a private school, aged between 5 and 11 years old, in Sao Paulo State, Brazil. To characterize the groups, data based on socioeconomic status, sanitation and housing conditions were collected. Anthropometric measurements and neonatal data were obtained from both groups. Gut microbiota were quantified in fecal samples by real-time PCR. Results: The children in the private school group had higher rates of Cesarean section and premature birth than the children in the slum group. Staphylococcus aureus (90% vs. 48.0%) and Clostridium difficile (100% vs. 43.0%) were more commonly found in the children from the private school than in the impoverished children (p

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Propofol, but not ketamine or midazolam, exerts neuroprotection after ischaemic injury by inhibition of Toll-like receptor 4 and nuclear factor kappa-light-chain-enhancer of activated B-cell signalling: A combined in vitro and animal study.

BACKGROUND: Propofol, midazolam and ketamine are widely used in today's anaesthesia practice. Both neuroprotective and neurotoxic effects have been attributed to all three agents. OBJECTIVE: To establish whether propofol, midazolam and ketamine in the same neuronal injury model exert neuroprotective effects on injured neurones in vitro and in vivo by modulation of the Toll-like receptor 4-nuclear factor kappa-light-chain-enhancer of activated B cells (TLR-4-NF-[kappa]B) pathway. DESIGN AND SETTING: Cell-based laboratory (n = 6 repetitions per experiment) and animal (n = 6 per group) studies using a neuronal cell line (SH-SY5Y cells) and adult Sprague-Dawley rats. INTERVENTIONS: Cells were exposed to oxygen-glucose deprivation before or after treatment using escalating, clinically relevant doses of propofol, midazolam and ketamine. In animals, retinal ischaemia (60 min) was induced followed by reperfusion and randomised treatment with saline or propofol. MAIN OUTCOME MEASURES: Neuronal cell death was determined using flow-cytometry (mitochondrial membrane potential) and lactate dehydrogenase (LDH) release. Nuclear factor NF-[kappa]B and hypoxia-inducible factor 1 [alpha]-activity were analysed by DNA-binding ELISA, expression of NF-[kappa]B-dependent genes and TLR-4 by luciferase-assay and flow-cytometry, respectively. In animals, retinal ganglion cell density, caspase-3 activation and gene expression (TLR-4, NF-[kappa]B) were used to determine in vivo effects of propofol. Results were compared using ANOVA (Analysis of Variance) and t test. A P value less than 0.05 was considered statistically significant. RESULTS: Post-treatment with clinically relevant concentrations of propofol (1 to 10 [mu]g ml-1) preserved the mitochondrial membrane potential in oxygen-glucose deprivation-injured cells by 54% and reduced LDH release by 21%. Propofol diminished TLR-4 surface expression and preserved the DNA-binding activity of the protective hypoxia-inducible factor 1 [alpha] transcription factor. DNA-binding and transcriptional NF-[kappa]B-activity were inhibited by propofol. Neuronal protection and inhibition of TLR-4-NF-[kappa]B signalling were not consistently seen with midazolam or ketamine. In vivo, propofol treatment preserved rat retinal ganglion cell densities (cells mm-2, saline 1504 +/- 251 vs propofol 2088 +/- 144, P = 0.0001), which was accompanied by reduced neuronal caspase-3, TLR-4 and NF-[kappa]B expression. CONCLUSION: Propofol, but neither midazolam nor ketamine, provides neuroprotection to injured neuronal cells via inhibition of TLR-4-NF-[kappa]B-dependent signalling. (C) 2016 European Society of Anaesthesiology

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