Structured light enhanced entoptic stimuli for vision science applications.

The dichroic macular pigment in the Henle fiber layer in the fovea enables humans to perceive entoptic phenomena when viewing polarized blue light. In the standard case of linearly polarized stimuli, a faint bowtie-like pattern known as the Haidinger's brush appears in the central point of fixation. As the shape and clarity of the perceived signal is directly related to the health of the macula, Haidinger's brush has been used as a diagnostic marker in studies of early stage macular degeneration and central field visual dysfunction. However, due to the weak nature of the perceived signal the perception of the Haidinger's brush has not been integrated with modern clinical methods. Recent attempts have been made to increase the strength of the perceived signal by employing structured light with spatially varying polarization profiles. Here we review the advancements with the structured light stimuli and describe the current challenges and future prospects.

Endotracheal inflammatory myofibroblastic tumour: A rare cause of central airway occlusion in adults.

Inflammatory myofibroblastic tumour (IMT) is an unusual myofibroblastic spindle cell neoplasm that is rarely discovered in the airway of adults. Previously, it was regarded as a reactive lesion and was infamously known as inflammatory pseudotumour before recent insights revealed that significant majority of cases harboured neoplastic genes. Diagnosis is difficult as clinical presentation and imaging findings are non-specific. Diagnosis and a favourable prognosis require the complete resection of the tumour. Detection of the anaplastic lymphoma kinase expression via immunohistochemistry expedites diagnosis. We report a young adult with an endotracheal mass occluding the central airway. The patient successfully underwent bronchoscopic resection using interventional techniques. IMT was diagnosed. No recurrence was seen after a year of surveillance. Due to the rarity of the disease, the recurrence rates for large airway disease is unknown. Recurrence rates for pulmonary lesions is reported to be lower compared to extrapulmonary IMTs and recurrence is unlikely if compete surgical excision is achieved.

Multifocal Primary Intrapulmonary Thymoma: A rare subtype of ectopic thymoma.

Primary Intrapulmonary Thymoma (PIT) is an infrequent ectopic lung tumor that poses a diagnostic dilemma and has a poorly understood origin. We report a previously healthy 61-year-old lady who presented with cough and weight loss for a month. Diagnostic imaging showed a large left upper lobe mass and two multifocal pleural based nodules in the left lower lobe. She underwent Computed Tomography (CT) guided biopsy of the lung mass and histopathological findings was consistent with a combined Type B1 and B2 thymoma. She was planned for 6 cycles of neoadjuvant chemotherapy with the intent of achieving tumor downstaging and resectability. Due to the lack of established evidence for management of unresectable disease, we wish to highlight the importance of multidisciplinary consensus before pursuing multimodality treatment.

Discovery of hemocompatible bacterial biofilm-resistant copolymers.

Blood-contacting medical devices play an important role within healthcare and are required to be biocompatible, hemocompatible and resistant to microbial colonization. Here we describe a high throughput screen for copolymers with these specific properties. A series of weakly amphiphilic monomers are combinatorially polymerized with acrylate glycol monomers of varying chain lengths to create a library of 645 multi-functional candidate materials containing multiple chemical moieties that impart anti-biofilm, hemo- and immuno-compatible properties. These materials are screened in over 15,000 individual biological assays, targeting two bacterial species, one Gram negative (Pseudomonas aeruginosa) and one Gram positive (Staphylococcus aureus) commonly associated with central venous catheter infections, using 5 different measures of hemocompatibility and 6 measures of immunocompatibililty. Selected copolymers reduce platelet activation, platelet loss and leukocyte activation compared with the standard comparator PTFE as well as reducing bacterial biofilm formation in vitro by more than 82% compared with silicone. Poly(isobornyl acrylate-co-triethylene glycol methacrylate) (75:25) is identified as the optimal material across all these measures reducing P. aeruginosa biofilm formation by up to 86% in vivo in a murine foreign body infection model compared with uncoated silicone.

The impact of surface chemistry modification on macrophage polarisation.

Macrophages are innate immune cells that have a central role in combating infection and maintaining tissue homeostasis. They exhibit remarkable plasticity in response to environmental cues. At either end of a broad activation spectrum are pro-inflammatory (M1) and anti-inflammatory (M2) macrophages with distinct functional and phenotypical characteristics. Macrophages also play a crucial role in orchestrating immune responses to biomaterials used in the fabrication of implantable devices and drug delivery systems. To assess the impact of different surface chemistries on macrophage polarisation, human monocytes were cultured for 6 days on untreated hydrophobic polystyrene (PS) and hydrophilic O2 plasma-etched polystyrene (O2-PS40) surfaces. Our data clearly show that monocytes cultured on the hydrophilic O2-PS40 surface are polarised towards an M1-like phenotype, as evidenced by significantly higher expression of the pro-inflammatory transcription factors STAT1 and IRF5. By comparison, monocytes cultured on the hydrophobic PS surface exhibited an M2-like phenotype with high expression of mannose receptor (MR) and production of the anti-inflammatory cytokines IL-10 and CCL18. While the molecular basis of such different patterns of cell differentiation is yet to be fully elucidated, we hypothesise that it is due to the adsorption of different biomolecules on these surface chemistries. Indeed our surface characterisation data show quantitative and qualitative differences between the protein layers on the O2-PS40 surface compared to PS surface which could be responsible for the observed differential macrophage polarisation on each surface.

Octreotide in malignant chylothorax: a case report.

The treatment of malignancy-associated chylous pleural effusion and ascites, especially in the palliative setting, represents a major therapeutic challenge. Our patient, a case of metastatic lung cancer, was suffering from high-output, non-resolving, malignancy-related chylothorax. We found that subcutaneous octreotide in combination with fasting and total parenteral nutrition, followed later by institution of low-fat diet, resulted in its resolution. We suggest that it is a reasonable approach associated with minimal morbidity in what is otherwise a challenging clinical condition.

Discovery of a Novel Polymer for Human Pluripotent Stem Cell Expansion and Multilineage Differentiation.

A scalable and cost-effective synthetic polymer substrate that supports robust expansion and subsequent multilineage differentiation of human pluripotent stem cells (hPSCs) with defined commercial media is presented. This substrate can be applied to common cultureware and used off-the-shelf after long-term storage. Expansion and differentiation of hPSCs are performed entirely on the polymeric surface, enabling the clinical potential of hPSC-derived cells to be realized.

Palliative care in South Asia: a systematic review of the evidence for care models, interventions, and outcomes.

BACKGROUND: The increasing incidence of cancer and chronic diseases in South Asia has created a growing public health and clinical need for palliative care in the region. As an emerging discipline with increasing coverage, palliative care must be guided by evidence. In order to appraise the state of the science and inform policy and best practice in South Asia this study aimed to systematically review the evidence for palliative care models, interventions, and outcomes. RESULTS: The search identified only 16 articles, reporting a small range of services. The 16 articles identified India as having greatest number of papers (n = 14) within South Asia, largely focused in the state of Kerala. Nepal and Pakistan reported a single study each, with nothing from Bhutan, Afghanistan, Maldives or Bangladesh. Despite the large population of South Asia, we found only 4 studies reporting intervention outcomes, with the remaining reporting service descriptions (n = 12). CONCLUSIONS: The dearth of evidence in terms of palliative care outcomes, and the lack of data from beyond India, highlight the urgent need for greater research investment and activity to guide the development of feasible, acceptable, appropriate and effective palliative care services. There is some evidence that suggests implementation of successful and well-developed community based models of palliative care may be replicated in other resource limited settings. Greater investigation to determine outcomes and costs are urgently needed, and require well-designed and validated tools to measure outcomes. Studies are also needed to better understand the cultural context of death and dying for patients and their families in South Asia, and to respond to the growing need for palliative and end-of-life care in the region.