Stair ascent and descent in assessing donor site morbidity following osteocutaneous free fibula transfer : a preliminary study

Purpose: We wanted to investigate the gait kinematic parameters during stairs ascent and descent after a fibula free flap (FFF) removal for facial reconstruction. Methods: Eight patients who underwent facial reconstruction with FFF ascended and descended three standard steps. Their movements were recorded by a motion analyzer; gait kinematic parameters were obtained and compared to those calculated in eight control subjects. Results: Stride time, percentage of swing and support phases did not differ among healthy or operated limb, and control subjects (Kruskal Wallis, p>0.05). No significant differences were found for hip and knee movements, pelvis rotation and tilt, and body center of mass displacements. During stair descent, the patients had a significantly larger pelvis inclination than the control subjects (p<0.05). Conclusion: No functional limitations during stair performance were found. The only significant difference could indicate a minor control of the pelvis, and should be used to define specific rehabilitative interventions

Myo-Inositol based nano-PCM for Solar Thermal Energy Storage

The thermo-physical behavior of Myo-Inositol (MI), (a sugar alcohol), was investigated as a potential material for developing more compact solar thermal energy storage systems than those currently available. This latent heat storage medium could be utilized for commercial and industrial applications using solar thermal energy storage in the temperature range of 160°C to 260°C, if its thermal performance was modified. The objective of this investigation was to determine via experimentation, if Al2O3 and CuO nanoparticles dispersed in pure MI for mixtures of 1, 2 and 3% (by weight) improved the thermal performance of MI for solar thermal energy systems. Nanoparticles only physically interacted with MI, and not chemically, even after 50 thermal cycles. The distribution of CuO nanoparticles in the nano-PCM was found to be more uniform than alumina nanoparticles. After cycling, nano-MIs studied here suffered a lower decrease in heat of fusion than pure MI, which makes nano-MIs more suitable for solar thermal storage applications at 160°C to 260°C. Between CuO and Al2O3 nanoparticles, latter was found to be more suitable for compact solar thermal energy storage owing to an increase in melting point observed

Antibiotic treatment-induced dysbiosis differently affects BDNF and TrkB expression in the brain and in the gut of juvenile mice

Antibiotic use during adolescence may result in dysbiosis-induced neuronal vulnerability both in the enteric nervous system (ENS) and central nervous system (CNS) contributing to the onset of chronic gastrointestinal disorders, such as irritable bowel syndrome (IBS), showing significant psychiatric comorbidity. Intestinal microbiota alterations during adolescence influence the expression of molecular factors involved in neuronal development in both the ENS and CNS. In this study, we have evaluated the expression of brain-derived neurotrophic factor (BDNF) and its high-affinity receptor tropomyosin-related kinase B (TrkB) in juvenile mice ENS and CNS, after a 2-week antibiotic (ABX) treatment. In both mucosa and mucosa-deprived whole-wall small intestine segments of ABX-treated animals, BDNF and TrKB mRNA and protein levels significantly increased. In longitudinal muscle-myenteric plexus preparations of ABX-treated mice the percentage of myenteric neurons staining for BDNF and TrkB was significantly higher than in controls. After ABX treatment, a consistent population of BDNF-and TrkB-immunoreactive neurons costained with SP and CGRP, suggesting up-regulation of BDNF signaling in both motor and sensory myenteric neurons. BDNF and TrkB protein levels were downregulated in the hippocampus and remained unchanged in the prefrontal cortex of ABX-treated animals. Immunostaining for BDNF and TrkB decreased in the hippocampus CA3 and dentate gyrus subregions, respectively, and remained unchanged in the prefrontal cortex. These data suggest that dysbiosis differentially influences the expression of BDNF-TrkB in the juvenile mice ENS and CNS. Such changes may potentially contribute later to the development of functional gut disorders, such as IBS, showing psychiatric comorbidity

Investigations into nanofluids as direct solar radiation collectors

Nanofluids that directly absorb solar radiation have been proposed as an alternative to selectively coated metallic receivers in solar thermal collectors. Given the expense of characterising a potential nanofluid experimentally methods for comparing nanofluids virtually are needed. This paper develops a computational wave optics model using COMSOL to simulate the absorption of nanoparticles suspended in a fluid for solar radiation (380–800 nm) and compares it to experimental results using reflectance and transmission spectrometry. It was concluded that while both yielded data with matching trends, the exact absorption of some fluids differed by up to 1 AU. Optical characteristics of nanofluids comprising ethylene glycol (melting point −12.99 °C and boiling point range 195–198 °C at 1013 h Pa) and graphene oxide (sheets size 5 nm × 19 nm × 19 nm, volume fraction 0.004–0.016%) have been experimentally measured. An optimum volume fraction of 0.012% of graphene oxide has been identified achieving a minimum reflectance and highest absorbance over the visible spectral range.Authors, Rose, Singh, Tassou, Suresh and Anathraman, thankfully acknowledge the UKIERI-DST grant (IND/CONT/E/14-15/381) which made this research possible

Acoustic Phonon-Assisted Resonant Tunneling via Single Impurities

We perform the investigations of the resonant tunneling via impurities embedded in the AlAs barrier of a single GaAs/AlGaAs heterostructure. In the $I(V)$ characteristics measured at 30mK, the contribution of individual donors is resolved and the fingerprints of phonon assistance in the tunneling process are seen. The latter is confirmed by detailed analysis of the tunneling rates and the modeling of the resonant tunneling contribution to the current. Moreover, fluctuations of the local structure of the DOS (LDOS) and Fermi edge singularities are observed.Comment: accepted in Phys. Rev.

Microparticle-mediated transfer of the viral receptors CAR and CD46, and the CFTR channel in a CHO cell model confers new functions to target cells

Cell microparticles (MPs) released in the extracellular milieu can embark plasma membrane and intracellular components which are specific of their cellular origin, and transfer them to target cells. The MP-mediated, cell-to-cell transfer of three human membrane glycoproteins of different degrees of complexity was investigated in the present study, using a CHO cell model system. We first tested the delivery of CAR and CD46, two monospanins which act as adenovirus receptors, to target CHO cells. CHO cells lack CAR and CD46, high affinity receptors for human adenovirus serotype 5 (HAdV5), and serotype 35 (HAdV35), respectively. We found that MPs derived from CHO cells (MP-donor cells) constitutively expressing CAR (MP-CAR) or CD46 (MP-CD46) were able to transfer CAR and CD46 to target CHO cells, and conferred selective permissiveness to HAdV5 and HAdV35. In addition, target CHO cells incubated with MP-CD46 acquired the CD46-associated function in complement regulation. We also explored the MP-mediated delivery of a dodecaspanin membrane glycoprotein, the CFTR to target CHO cells. CFTR functions as a chloride channel in human cells and is implicated in the genetic disease cystic fibrosis. Target CHO cells incubated with MPs produced by CHO cells constitutively expressing GFP-tagged CFTR (MP-GFP-CFTR) were found to gain a new cellular function, the chloride channel activity associated to CFTR. Time-course analysis of the appearance of GFP-CFTR in target cells suggested that MPs could achieve the delivery of CFTR to target cells via two mechanisms: the transfer of mature, membrane-inserted CFTR glycoprotein, and the transfer of CFTR-encoding mRNA. These results confirmed that cell-derived MPs represent a new class of promising therapeutic vehicles for the delivery of bioactive macromolecules, proteins or mRNAs, the latter exerting the desired therapeutic effect in target cells via de novo synthesis of their encoded proteins

A novel integrated platform for the identification of surgical margins in oral squamous cell carcinoma: results from a prospective single-institution series

BackgroundThe optimal surgical margins assessment is capital in oral squamous cell carcinoma (OSCC) management. We evaluated the clinical benefits of integrating intraoperative macroscopic margin (MM) assessment and narrow band imaging (NBI).MethodsSixteen OSCC patients eligible for surgery were prospectively enrolled. For each patient, 2 to 6 bioptic samples of MM and NBI margins were obtained and histologically analyzed for the presence of dysplasia and lymphocytes. Microvessel density was investigated by CD34 immunohistochemistry.ResultsTaken together, 104 specimens were analyzed, including 15% tumors, 33% MM, 33% NBI margins, and 19% MM-NBI overlapping margins. The NBI margins were closer to the lesion in 50% cases, while the same number of MM were more conservative than NBI, irrespective of the tumor site. The rate of histologically positive margins was similar among the two methods, akin to the microvessel density.ConclusionsMM assessment should be integrated but not replaced with the NBI technology to allow for more conservative surgery

Aptamer-based field-effect biosensor for tenofovir detection

During medical treatment it is critical to maintain the circulatory concentration of drugs within their therapeutic range. A novel biosensor is presented in this work to address the lack of a reliable point-of-care drug monitoring system in the market. The biosensor incorporates high selectivity and sensitivity by integrating aptamers as the recognition element and field-effect transistors as the signal transducer. The drug tenofovir was used as a model small molecule. The biointerface of the sensor is a binary self-assembled monolayer of specific thiolated aptamer and 6-mercapto-1-hexanol (MCH), whose ratio was optimized by electrochemical impedance spectroscopy measurements to enhance the sensitivity towards the specific target. Surface plasmon resonance, performed under different buffer conditions, shows optimum specific and little non-specific binding in phosphate buffered saline. The dose-response behavior of the field-effect biosensor presents a linear range between 1 nM and 100 nM of tenofovir and a limit of detection of 1.2 nM. Two non-specific drugs and one non-specific aptamer, tested as stringent control candidates, caused negligible responses. The applications were successfully extended to the detection of the drug in human serum. As demonstrated by impedance measurements, the aptamer-based sensors can be used for real-time drug monitoring