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The paper describes an experimental, mechanically simple, tactile sensing solution in the form of a sensing chair for discriminating human motion in a reaching task. This cost-efficient technical approach was employed for the assessment of selective arm movements in stroke survivors. The sensing system classifies trunk motion in a seated stroke survivor during a goal-directed task where there is direct correlation with the level of severity of arm movement. The system interprets motion mechanically from coupled sensory data transients using artificial neural networks and shows tolerance to patients' sitting posture and performance variability. The accuracy of classification was typically greater than 94% across three categories when applied to a group of stroke survivors of wide-ranging motor abilities. The mechanical simplicity, versatility of approach for use in other classes of movement, and potential low cost of manufacturing provides opportunity to employ the system at clinics and homes for assessment and training. [ABSTRACT FROM AUTHOR]

The concept of a hand guided robotic drill has been inspired by an automated, arm supported robotic drill recently applied in clinical practice to produce cochleostomies without penetrating the endosteum ready for inserting cochlear electrodes. The smart tactile sensing scheme within the drill enables precise control of the state of interaction between tissues and tools in real-time. This paper reports development studies of the hand guided robotic drill where the same consistent outcomes, augmentation of surgeon control and skill, and similar reduction of induced disturbances on the hearing organ are achieved. The device operates with differing presentation of tissues resulting from variation in anatomy and demonstrates the ability to control or avoid penetration of tissue layers as required and to respond to intended rather than involuntary motion of the surgeon operator. The advantage of hand guided over an arm supported system is that it offers flexibility in adjusting the drilling trajectory. This can be important to initiate cutting on a hard convex tissue surface without slipping and then to proceed on the desired trajectory after cutting has commenced. The results for trials on phantoms show that drill unit compliance is an important factor in the design. [ABSTRACT FROM AUTHOR]

Robotic assistance in the context of lateral skull base surgery, particularly during cochlear implantation procedures, has been the subject of considerable research over the last decade. The use of robotics during these procedures has the potential to provide significant benefits to the patient by reducing invasiveness when gaining access to the cochlea, as well as reducing intracochlear trauma when performing a cochleostomy. Presented herein is preliminary work on the combination of two robotic systems for reducing invasiveness and trauma in cochlear implantation procedures. A robotic system for minimally invasive inner ear access was combined with a smart drilling tool for robust and safe cochleostomy; evaluation was completed on a single human cadaver specimen. Access to the middle ear was successfully achieved through the facial recess without damage to surrounding anatomical structures; cochleostomy was completed at the planned position with the endosteum remaining intact after drilling as confirmed by microscope evaluation. [ABSTRACT FROM AUTHOR]

• A novel approach to use complex electrical impedance (magnitude and phase) to predict electrode array path. • Use of machine learning algorithms to classify paths due to different insertion trajectories. • Reasonable overall accuracy results of full and partial insertions. • Partial insertion results are capable for real time electrode array positioning during automated insertion. Cochlear Implant provides an electronic substitute for hearing to severely or profoundly deaf patients. However, postoperative hearing outcomes significantly depend on the proper placement of electrode array (EA) into scala tympani (ST) during cochlear implant surgery. Due to limited intra-operative methods to access array placement, the objective of the current study was to evaluate the relationship between EA complex impedance and different insertion trajectories in a plastic ST model. A prototype system was designed to measure bipolar complex impedance (magnitude and phase) and its resistive and reactive components of electrodes. A 3-DoF actuation system was used as an insertion feeder. 137 insertions were performed from 3 different directions at a speed of 0.08 mm/s. Complex impedance data of 8 electrode pairs were sequentially recorded in each experiment. Machine learning algorithms were employed to classify both the full and partial insertion lengths. Support Vector Machine (SVM) gave the highest 97.1% accuracy for full insertion. When a real-time prediction was tested, Shallow Neural Network (SNN) model performed better than other algorithms using partial insertion data. The highest accuracy was found at 86.1% when 4 time samples and 2 apical electrode pairs were used. Direction prediction using partial data has the potential of online control of the insertion feeder for better EA placement. Accessing the position of the electrode array during the insertion has the potential to optimize its intraoperative placement that will result in improved hearing outcomes. [ABSTRACT FROM AUTHOR]

Abstract: Blood genomic profiling has been applied to disorders of the blood and various organ systems including brain to elucidate disease mechanisms and identify surrogate disease markers. Since most studies have not examined specific cell types, we performed a preliminary genomic survey of major blood cell types from normal individuals using microarrays. CD4+ T cells, CD8+ T cells, CD19+ B cells, CD56+ natural killer cells, and CD14+ monocytes were negatively selected using the RosetteSep antibody cocktail, while polymorphonuclear leukocytes were separated with density gradient media. Genes differentially expressed by each cell type were identified. To demonstrate the potential use of such cell subtype-specific genomic expression data, a number of the major genes previously reported to be regulated in ischemic stroke, migraine, and Tourette syndrome are shown to be associated with distinct cell populations in blood. These specific gene expression, cell-type-related profiles will need to be confirmed in larger data sets and could be used to study these and many other neurological diseases. [Copyright &y& Elsevier]

The adsorption properties of individual fullerene molecules at room-temperature have been investigated by scanning tunneling microscopy. Statistical analysis of the images demonstrates that fullerene molecules prefer to adsorb on five specific sites: corner hole, the middle of the faulted and unfaulted parts, and the top of the rest atoms within the faulted and unfaulted parts. High-resolution images of individual fullerene molecules on each of the adsorption sites show distinct intramolecular structures. By combining these internal fine structures with theoretical simulations, the molecular orientations at each of the adsorption sites can be unambiguously determined. [ABSTRACT FROM AUTHOR]

Insulin resistance, diabetes and many kinds of cancers are common in overweight and obese individuals. The tumor suppressor p53 is important in securing genetic stability, but its role in the regulation of metabolic processes and cell differentiation remains unclear. We have investigated the role of p53 in adipocyte differentiation. Using 3T3-L1 cells, a mouse embryonic fibroblast preadipocyte model and DIO rat model, p53 expression and function during adipocyte differentiation were investigated. p53 expression increased on the second and fourth day of adipocyte differentiation and decreased thereafter. Its overexpression in 3T3-L1 preadipocytes markedly reduced adipogenesis and marker gene expression. p53 activity was weakened in DIO rat abdominal adipose tissue because of an decreased expression of its activated phosphorylated form. In contrast, p53 knockout enhanced adipogenesis and the expression of marker genes, but significantly reduced insulin-stimulated Akt phosphorylation. These results indicate that p53 partly suppresses preadipocyte differentiation and adipogenesis by regulating adipocyte gene expression and Akt signaling. [ABSTRACT FROM AUTHOR]

Abstract: The influence of Ag atoms on the adsorption statuses of individual fullerene molecules on Si surface at room temperature has been investigated by scanning tunneling microscopy. For a fullerene molecule, its adsorption status can be switched from one initial state into multiple final states by attaching Ag atoms onto various parts of the molecule. Once silver atoms are removed from the adsorption sites by a STM tip, the adsorption statuses of the fullerene molecules are recovered as that for fullerene molecules on a bare Si surface. [Copyright &y& Elsevier]

Pediatric strokes are rare but critical diagnoses to make in the emergency setting. They are associated with a set of pathologies that are not frequently encountered in the adult population. Some of these diseases have variable clinical presentations and imaging appearance depending on the age of onset and severity of the underlying pathologies. This article reviews the differential diagnoses and noninvasive imaging evaluation of pediatric cerebral ischemic and hemorrhagic diseases. [ABSTRACT FROM AUTHOR]

The fit of a lower limb prosthetic socket is critical for user comfort and the quality of life of lower limb amputees. Sockets are conventionally produced using hand-crafted patient-based casting techniques. Modern digital techniques offer a host of advantages to the process and ultimately lead to improving the lives of amputees. However, commercially available scanning equipment required is often expensive and proprietary. Smartphone photogrammetry could offer a low cost alternative, but there is no widely accepted imaging technique for prosthetic socket digitisation. Therefore, this paper aims to determine an optimal imaging technique for whole socket photogrammetry and evaluate the resultant scan measurement accuracy. A 3D printed transtibial socket was produced to create digital and physical twins, as reference models. The printed socket was photographed from 360 positions and simplified genetic algorithms were used to design a series of experiments, whereby a collection of photos were processed using Autodesk ReCap. The most fit technique was used to assess accuracy. The accuracy of the socket wall volume, surface area and height were 61.63%, 99.61% and 99.90%, respectively, when compared to the digital reference model. The scanned model had a wall thickness ranging from 2.075 mm at the top to 7.758 mm towards the base of the socket, compared to a consistent thickness of 2.025 mm in the control model. The technique selected did not show sufficient accuracy for clinical application due to the degradation of accuracy nearer to the base of the socket interior. However, using an internal wall thickness estimation, scans may be of sufficient accuracy for clinical use; assuming a uniform wall thickness. [ABSTRACT FROM AUTHOR]

The leukocyte integrin alpha(M)beta(2)/Mac-1 appears to support the inflammatory response through multiple ligands, but local engagement of fibrin(ogen) may be particularly important for leukocyte function. To define the biological significance of fibrin(ogen)-alpha(M)beta(2) interaction in vivo, gene-targeted mice were generated in which the alpha(M)beta(2)-binding motif within the fibrinogen gamma chain (N(390)RLSIGE(396)) was converted to a series of alanine residues. Mice carrying the Fibgamma(390-396A) allele maintained normal levels of fibrinogen, retained normal clotting function, supported platelet aggregation, and never developed spontaneous hemorrhagic events. However, the mutant fibrinogen failed to support alpha(M)beta(2)-mediated adhesion of primary neutrophils, macrophages, and alpha(M)beta(2)-expressing cell lines. The elimination of the alpha(M)beta(2)-binding motif on fibrin(ogen) severely compromised the inflammatory response in vivo as evidenced by a dramatic impediment in leukocyte clearance of Staphylococcus aureus inoculated into the peritoneal cavity. This defect in bacterial clearance was due not to diminished leukocyte trafficking but rather to a failure to fully implement antimicrobial functions. These studies definitively demonstrate that fibrin(ogen) is a physiologically relevant ligand for alpha(M)beta(2), integrin engagement of fibrin(ogen) is critical to leukocyte function and innate immunity in vivo, and the biological importance of fibrinogen in regulating the inflammatory response can be appreciated outside of any alteration in clotting function. [ABSTRACT FROM AUTHOR]