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Cell migration is a central biological process that requires fine coordination of molecular events in time and space. A deregulation of the migratory phenotype is also associated with pathological conditions including cancer where cell motility has a causal role in tumor spreading and metastasis formation. Thus cell migration is of critical and strategic importance across the complex disease spectrum as well as for the basic understanding of cell phenotype. Experimental studies of the migration of cells in monolayers are often conducted with ‘wound healing’ assays. Analysis of these assays has traditionally relied on how the wound area changes over time. However this method does not take into account the shape of the wound. Given the many options for creating a wound healing assay and the fact that wound shape invariably changes as cells migrate this is a significant flaw. Here we present a novel software package for analyzing concerted cell velocity in wound healing assays. Our method encompasses a wound detection algorithm based on cell confluency thresholding and employs a Bayesian approach in order to estimate concerted cell velocity with an associated likelihood. We have applied this method to study the effect of siRNA knockdown on the migration of a breast cancer cell line and demonstrate that cell velocity can track wound healing independently of wound shape and provides a more robust quantification with significantly higher signal to noise ratios than conventional analyses of wound area. The software presented here will enable other researchers in any field of cell biology to quantitatively analyze and track live cell migratory processes and is therefore expected to have a significant impact on the study of cell migration, including cancer relevant processes. Installation instructions, documentation and source code can be found at licensed under GPLv3. [ABSTRACT FROM AUTHOR]

We here present an update of the PERISCOP pressurised recovery device (PRD), which has allowed the recovery of live deep-sea fauna, following active sampling by manned or remotely-operated submersibles. It was designed in 2006, has since been deployed almost a hundred times (93), and its operation has now become almost routine. Various hydrothermal vent megafaunal organisms (shrimp, crabs, annelids, mussels, fish,..) were successfully targeted and recovered, allowing access to samples in excellent physiological condition. Gradually, the system was modified, aiming at improved reliability, depth of operation, and simplicity of use, especially regarding its compensator, i.e. the system that compensates for pressure loss experienced during ascent through the water column. Two types of compensators are presented, called "active" and "passive" (with so-called "water-filled" or "oil-filled" modes regarding the latter). Their respective uses are reported and discussed here, and while the active system proves more efficient (recovering at minimum pressure in the range 93.8–98.2% of in situ pressure, as opposed to 80.9–86.6% for the water-filled passive system, while no compensation leads to a range of 63.5–73.0%), the simplicity of the passive compensator greatly improves reliability and ease of use and maintenance. Finally, the monitoring of pressure and temperature of the PRD and the surrounding water column permits to discuss various technical aspects of pressurised recovery, and to propose further improvements. • The PERISCOP pressurised recovery device (PRD) aims at recovering live deep-sea fauna, following active sampling by manned or remotely-operated submersibles. It has been deployed almost a hundred times (93) since its initial design in 2006, at depths ranging from 800 to 3600 m. Its operation has now become almost routine, with the successful recovery of various hydrothermal vent megafaunal organisms (shrimp, crabs, annelids, mussels, fish,..), in excellent physiological condition. Several improvements of the system are presented in terms of reliability, depth of deployment, simplicity of use, and a focus is made on its compensator, i.e. the system that compensates for pressure loss experienced during ascent through the water column. Two types of compensators are presented, called "active" and "passive". Their respective uses are reported and discussed here, and while the active system proves more efficient, the simplicity of the passive compensator greatly improves reliability and ease of use. Finally, in the light of the field experience acquired with the PERISCOP PRD, various technical aspects of pressurised recovery are discussed, and further improvements are proposed. [ABSTRACT FROM AUTHOR]

Author summary: Here, we describe the development of the MosqTent, an innovative double-chamber mosquito trap in which a human being attracts mosquitoes while is protected from being bitten within the inner chamber of the trap, while mosquitoes are lured to enter an outer chamber where they are trapped. The MosqTent previously collected an average of 3,000 anophelines/man-hour compared to 240 anophelines/man-hour for the human landing catch (HLC), thereby providing high numbers of human host–seeking mosquitoes while protecting the collector from mosquito bites. The MosqTent performed well by collecting a high number of specimens of Anopheles marajoara, a local vector and anthropophilic mosquito species present in high density, but not so well in collecting An. darlingi, an anthropophilic mosquito species considered the main vector in Brazil but is present in low-density conditions in the area. The HLC showed a higher efficiency in collecting An. darlingi in these low-density conditions. The MosqTent is light (<1 kg), portable (comes as a bag with two handles), flexible (can be used with other attractants), adaptable (can be deployed in a variety of environmental settings and weather conditions), and it can be used in the intra-, peri-, and in the extradomicile. Also, the MosqTent collected similar portions of parous females and anthropophilic mosquito species and collects specimens suitable for downstream analysis. Further developments may include testing for other fabric colors, different mesh sizes and dimensions for other hematophagous insects and conditions, additional chemical mosquito attractants, and even the replacement of the human attractant in favor of other attractants. MosqTent modifications that would allow the trap to be applied as a vector control tool with killing action could also be explored. [ABSTRACT FROM AUTHOR]

Recommendations for fertilizing irrigated rice in southern Brazil have been constantly evolving over years. In this process, the influence of factors such as the development cycle of varieties and sowing period increased. Thus, computational tools that take these and others important aspects into account can potentiate the fertilization response of rice. This study describes the computer program "ADUBARROZ". The software provides recommendations of fertilizer rates and liming requirements of irrigated rice, based on information entered by the user. The system takes various factors that regulate the crop response to fertilization into account. A final report is established with the graphical representation of input management over time. [ABSTRACT FROM AUTHOR]

The synapse is the focus of experimental research and theory on the cellular mechanisms of nervous system plasticity and learning, but recent research is expanding the consideration of plasticity into new mechanisms beyond the synapse, notably including the possibility that conduction velocity could be modifiable through changes in myelin to optimize the timing of information transmission through neural circuits. This concept emerges from a confluence of brain imaging that reveals changes in white matter in the human brain during learning, together with cellular studies showing that the process of myelination can be influenced by action potential firing in axons. This Opinion article summarizes the new research on activity-dependent myelination, explores the possible implications of these studies and outlines the potential for new research. [ABSTRACT FROM AUTHOR]

Autoimmunity in rheumatoid arthritis (RA) is characterized by an antibody response to citrullinated proteins. Two of the risk factors for RA-HLA-DRB1 shared epitope alleles and smoking-are also associated with periodontitis, which is largely, but not exclusively, caused by Porphyromonas gingivalis infection. Furthermore, RA and periodontitis have a similar pathophysiology, characterized by destructive inflammation. The citrullination of proteins by P. gingivalis and the subsequent generation of autoantigens that drive autoimmunity in RA represents a possible causative link between these two diseases. Antibodies directed towards the immunodominant epitope of human citrullinated α-enolase cross-react with a conserved sequence on citrullinated P. gingivalis enolase. On the basis of this cross-reactivity, in this Perspectives article we explore the hypothesis of molecular mimicry in the etiology of RA, with citrullinated enolase as the specific antigen involved. [ABSTRACT FROM AUTHOR]

The precise mechanisms whereby anti-angiogenesis therapy blocks tumour growth or causes vascular toxicity are unknown. We propose that endothelial cells establish a vascular niche that promotes tumour growth and tissue repair not only by delivering nutrients and O2 but also through an 'angiocrine' mechanism by producing stem and progenitor cell-active trophogens. Identification of endothelial-derived instructive angiocrine factors will allow direct tumour targeting, while diminishing the unwanted side effects associated with the use of anti-angiogenic agents. [ABSTRACT FROM AUTHOR]

Traditional descriptions of the cortical cholinergic input system focused on the diffuse organization of cholinergic projections and the hypothesis that slowly changing levels of extracellular acetylcholine (ACh) mediate different arousal states. The ability of ACh to reach the extrasynaptic space (volume neurotransmission), as opposed to remaining confined to the synaptic cleft (wired neurotransmission), has been considered an integral component of this conceptualization. Recent studies demonstrated that phasic release of ACh, at the scale of seconds, mediates precisely defined cognitive operations. This characteristic of cholinergic neurotransmission is proposed to be of primary importance for understanding cholinergic function and developing treatments for cognitive disorders that result from abnormal cholinergic neurotransmission. [ABSTRACT FROM AUTHOR]

Children and adults with mobilily problems often suffer with contraction of unused muscles, which can consequently pose a risk to joint stability Both contraction and joint instability can be extremely painful, leading to among other issues, poor quality of sleep. Although seating provision attempts to maintain appropriate posture during the day, suitable equipment provision must also be considered for the night. Sleep systems aim to provide appropriate support, promote postural symmetry and increase quality of sleep. This article discusses the Moonlite Sleep System, manufactured by JCM. It describes the features and benefits of the system and summarizes client feedback to date. [ABSTRACT FROM AUTHOR]

Most tumours are derived from a single cell that is transformed into a cancer-initiating cell (cancer stem cell) that has the capacity to proliferate and form tumours in vivo. However, the origin of the cancer stem cell remains elusive. Interestingly, during development and tissue repair the fusion of genetic and cytoplasmic material between cells of different origins is an important physiological process. Such cell fusion and horizontal gene-transfer events have also been linked to several fundamental features of cancer and could be important in the development of the cancer stem cell. [ABSTRACT FROM AUTHOR]

The mammalian heart is crafted from a few progenitor cells that are subject to rapidly changing sets of instructions from their environment and from within. These instructions cause them to migrate, expand and diversify in lineage, and acquire form and function. Molecular information from various model systems, combined with increasingly detailed morphogenetic data, has provided insights into some of these key events. Many congenital heart abnormalities might arise from defects in the early stages of heart development, therefore it is important to understand the molecular pathways that underlie the lineage specification and patterning processes that shape this organ. [ABSTRACT FROM AUTHOR]