Aural health awareness and incident prevention in UK scuba divers.

Introduction: Otological disorders, including Eustachian tube dysfunction (ETD), are commonly observed in divers. Data were gathered to observe the prevalence of ear disorders, and awareness of ear health recommendations for recreational divers in the United Kingdom.

Methods: An anonymous online survey included: diver/diving demographics, the validated Eustachian Tube Dysfunction Questionnaire 7 (ETDQ-7) (a mean score of ≥ 2.

Rationalising requests for preoperative sleep studies and postoperative HDU beds: a quality improvement project in paediatric ENT patients undergoing elective surgery.

Background: Sleep disordered breathing represents a spectrum of upper airway obstruction including snoring, increased respiratory effort and obstructive sleep apnoea. An increasing demand for paediatric preoperative sleep studies and postoperative high dependency unit (HDU) beds was having a significant impact on service delivery at this ear, nose and throat (ENT) unit.

Methods: Retrospective and prospective review of all paediatric sleep study requests over a 30-month period in a single tertiary ENT department.

Controlled intracellular generation of reactive oxygen species in human mesenchymal stem cells using porphyrin conjugated nanoparticles.

Nanoparticles capable of generating controlled amounts of intracellular reactive oxygen species (ROS), that advance the study of oxidative stress and cellular communication, were synthesized by functionalizing polyacrylamide nanoparticles with zinc(II) porphyrin photosensitisers. Controlled ROS production was demonstrated in human mesenchymal stem cells (hMSCs) through (1) production of nanoparticles functionalized with varying percentages of Zn(II) porphyrin and (2) modulating the number of doses of excitation light to internalized nanoparticles. hMSCs challenged with nanoparticles functionalized with increasing percentages of Zn(II) porphyrin and high numbers of irradiations of excitation light were found to generate greater amounts of ROS.

Hematopoietic stem cell (CD34+) uptake of superparamagnetic iron oxide is enhanced by but not dependent on a transfection agent.

Background Aims: Tracking the fate of cells after infusion would be a valuable asset for many stem cell therapies, but very few (cell) labels are approved for human therapeutic use. Superparamagnetic iron oxide particles (SPIO) can be internalized into stem cells in vitro to allow real-time tracking with gradient echo magnetic resonance imaging, but SPIO are approved for (diagnostic) imaging and not for (therapeutic) cell labeling in vivo. In this study, we investigated the possibility of labeling stem cells with an SPIO approved for patient use, albeit in a novel manner by enhancing uptake with the use of a transfection agent, also approved for patient use.

Mesenchymal stem cells in the human corneal limbal stroma.

Purpose: Peripheral and limbal corneal stromal cells (PLCSCs), which contain keratocytes, have a complex phenotype. Knowledge of keratocyte cell properties, function, and origin is limited. Evidence available thus far has suggested both mesenchymal stromal and hematopoietic characteristics.

Granulocyte-colony stimulating factor for mobilizing bone marrow stem cells in subacute stroke: the stem cell trial of recovery enhancement after stroke 2 randomized controlled trial.

Background And Purpose: Granulocyte-colony stimulating factor (G-CSF) is neuroprotective in experimental stroke and mobilizes CD34(+) peripheral blood stem cells into the circulation. We assessed the safety of G-CSF in recent stroke in a phase IIb single-center randomized, controlled trial.

Methods: G-CSF (10 μg/kg) or placebo (ratio 2:1) was given SC for 5 days to 60 patients 3 to 30 days after ischemic or hemorrhagic stroke.

Internalisation of polymeric nanosensors in mesenchymal stem cells: analysis by flow cytometry and confocal microscopy.

The aim of this study was to demonstrate that flow cytometry and confocal microscopy could be applied in a complementary manner to analyse the internalisation of polymeric nanosensors in mesenchymal stem cells (MSC). The two techniques are able to provide en masse data analysis of nanosensors from large cell populations and detailed images of intracellular nanosensor localisation, respectively. The polyacrylamide nanosensors used in this investigation had been modified to contain free amine groups which were subsequently conjugated to Tat peptide, which acted as a delivery vector for nanosensor internalisation.

Hematopoiesis from human embryonic stem cells: overcoming the immune barrier in stem cell therapies.

The multipotency and proliferative capacity of human embryonic stem cells (hESCs) make them a promising source of stem cells for transplant therapies and of vital importance given the shortage in organ donation. Recent studies suggest some immune privilege associated with hESC-derived tissues. However, the adaptability of the immune system makes it unlikely that fully differentiated tissues will permanently evade immune rejection.

Expression of CD34 and L-selectin on human corneal keratocytes.

Purpose: To investigate the expression of CD34, a hematopoietic stem cell marker and an adhesion molecule, and its ligand L-selectin in the human cornea.

Methods: Seventeen normal adult human corneal specimens were studied by immunohistochemistry using a panel of monoclonal antibodies against all three classes of the hematopoietic stem cell marker CD34 and its ligand L-selectin. An additional six corneal specimens were used for protein extraction and analysis by Western blotting, using the CD34 and L-selectin antibodies.