Early reoperations in chronic subdural hematoma

Background: The recurrence rate of chronic subdural hematoma (cSDH) is high and early reoperation is often required. Aim: The aim of this study was to evaluate prognostic factors for early reoperation of chronic subdural hematomas (cSDH) treated by classical and minimally invasive approach. Materials and Methods: We retrospectively analyzed the medical history of 355 cSDH patients treated with formal craniotomy and minimally invasive burr hole craniostomy. We determined the potential predictors of early reoperations. Results: A total of 33 (9.3%) patients required early reoperation. Those patients more often underwent craniotomies instead of burr hole craniostomies (36.4% vs. 62.7%, p < 0.01) and took steroids before hospitalization (3.0% vs. 0.3%, p = 0.04) than non-reoperated patients. Patients who had surgery on the right side were less likely to be reoperated (51.9% vs. 33.3%, p = 0.04). On multivariate analysis the frontal (OR = 5.284, 95% CI: 1.293–21.76, p = 0.019) and large craniotomy (OR = 2.297, 95% CI: 1.004–5.258, p = 0.048) remained independent risk factors for early reoperation of cSDH. Conclusions: Neurosurgeons should consider the evacuation of a cSDH with help of minimally invasive burr hole craniostomy in most of the cases, as well as avoid large and frontal and craniotomies in order to prevent early reoperation of cSDH

Prefrontal and auditory input to intercalated neurons of the Amygdala

The basolateral amygdala (BLA) and prefrontal cortex (PFC) are partners in fear learning and extinction. Intercalated (ITC) cells are inhibitory neurons that surround the BLA. Lateral ITC (IITC) neurons provide feed-forward inhibition to BLA principal neurons, whereas medial ITC (mITC) neurons form an inhibitory interface between the BLA and central amygdala (CeA). Notably, infralimbic prefrontal (IL) input to mITC neurons is thought to play a key role in fear extinction. Here, using targeted optogenetic stimulation, we show that IITC neurons receive auditory input from cortical and thalamic regions. IL inputs innervate principal neurons in the BLA but not mITC neurons. These results suggest that (1) these neurons may play a more central role in fear learning as both IITCs and mITCs receive auditory input and that (2) mITC neurons cannot be driven directly by the IL, and their role in fear extinction is likely mediated via the BLA

Distributed Alarming in the On-Duty and Off-Duty Models

Decentralized monitoring and alarming systems can be an attractive alternative to centralized architectures. Distributed sensor nodes (e.g., in the smart grid's distribution network) are closer to an observed event than a global and remote observer or controller. This improves the visibility and response time of the system. Moreover, in a distributed system, local problems may also be handled locally and without overloading the communication network. This paper studies alarming from a distributed computing perspective and for two fundamentally different scenarios: on-duty and off-duty. We model the alarming system as a sensor network consisting of a set of distributed nodes performing local measurements to sense events. In order to avoid false alarms, the sensor nodes cooperate and only escalate an event (i.e., raise an alarm) if the number of sensor nodes sensing an event exceeds a certain threshold. In the on-duty scenario, nodes not affected by the event can actively help in the communication process, while in the off-duty scenario, non-event nodes are inactive. We present and analyze algorithms that minimize the reaction time of the monitoring system while avoiding unnecessary message transmissions. We investigate time and message complexity tradeoffs in different settings, and also shed light on the optimality of our algorithms by deriving cost lower bounds for distributed alarming systems.13 page(s

Switchable surface coatings for control over protein adsorption

Control over biomolecule interactions at interfaces is becoming an increasingly important goal for a range of scientific fields and is being intensively studied in areas of biotechnological, biomedical and materials science. Improvement in the control over materials and biomolecules is particularly important to applications such as arrays, biosensors, tissue engineering, drug delivery and 'lab on a chip' devices. Further development of these devices is expected to be achieved with thin coatings of stimuli responsive materials that can have their chemical properties 'switched' or tuned to stimulate a certain biological response such as adsorptionldesorption of proteins. Switchable coatings show great potential for the realisation of spatial and temporal immobilisation of cells and biomolecules such as DNA and proteins. This study focuses on protein adsorption onto coatings of the thermosensitive polymer poly(N-isopropylacrylamide) (pNIPAM) which can exhibit low and high protein adsorption properties based on its temperature dependent conformation. At temperatures above its lower critical solution temperature (LCST) pNIPAM polymer chains are collapsed and protein adsorbing whilst below the LCST they are hydrated and protein repellent. Coatings of pNIPAM on silicon wafers were prepared by free radical polymerisation in the presence of surface bound polymerisable groups. Surface analysis and protein adsorption was carried out using X-ray photoelectron spectroscopy, time of flight secondary ion mass spectrometry and contact angle measurements. This study is expected to aid the development of stimuli-responsive coatings for biochips and biodevices.Bellingham, US

Future challenges in cephalopod research

We thank Anto´nio M. de Frias Martins, past President of the Unitas Malacologica and Peter Marko, President of the American Malacological Society for organizing the 2013 World Congress of Malacology, and the Cephalopod International Advisory Committee for endorsing a symposium held in honour of Malcolm R. Clarke. In particular, we would like to thank the many professional staff from the University of the Azores for their hospitality, organization, troubleshooting and warm welcome to the Azores. We also thank Malcolm Clarke’s widow, Dorothy, his daughter Zoe¨, Jose´ N. Gomes-Pereira and numerous colleagues and friends of Malcolm’s from around the world for joining us at Ponta Delgada. We are grateful to Lyndsey Claro (Princeton University Press) for granting copyright permissions.Peer reviewedPublisher PD

Balanced interhemispheric cortical activity is required for correct targeting of the corpus callosum

Bilateral integration of sensory and associative brain processing is achieved by precise connections between homologous regions in the two hemispheres via the corpus callosum. These connections form postnatally, and unilateral deprivation of sensory or spontaneous cortical activity during a critical period severely disrupts callosal wiring. However, little is known about how this early activity affects precise circuit formation. Here, using in utero electroporation of reporter genes, optogenetic constructs, and direct disruption of activity in callosal neurons combined with whisker ablations, we show that balanced interhemispheric activity, and not simply intact cortical activity in either hemisphere, is required for functional callosal targeting. Moreover, bilateral ablation of whiskers in symmetric or asymmetric configurations shows that spatially symmetric interhemispheric activity is required for appropriate callosal targeting. Our findings reveal a principle governing axon targeting, where spatially balanced activity between regions is required to establish their appropriate connectivit