INVESTIGATING THE ROLE OF NOX NADPH OXIDASE SIGNALLING IN CELL MIGRATION AND ANGIOGENESIS OF ENDOTHELIAL COLONY-FORMING CELLS

Introduction. Endothelial colony-forming cells (ECFCs) hold great cytotherapeutic potential for ischaemic disease. Emerging evidence supports a key role for NADPH oxidases in underlying angiogenic processes of these and other endothelial cells. Aims. To study the influence of Nox NADPH oxidases on the pro-angiogenic function of ECFCs. Methods. Human ECFCs isolated from umbilical cord blood were treated with pro-oxidant PMA and assessed in vitro, both under basal conditions and after siRNA knockdown of Nox4, a key endothelial NADPH oxidase isoform, alongside primary mature human aortic endothelial cells (HAoECs) for comparison, using an established scratch-wound assay as the functional end-point. Results. PMA (500nM for 8h) increased cell migration (control 18.6±2.8, PMA 32.7±6.6% wound closure; n=6, P<0.05) in a superoxide-dependent manner, as indicated by attenuation of this effect in the presence of PEG-SOD. Although HAoEC migration in response to PMA also tended to increase, this did not reach statistical significance. Notably, cell migration at 16h was reduced by Nox4 knockdown in ECFCs (control siRNA 53.4±3.5, Nox4 siRNA 35.1±4.9% closure; n=3, P<0.05), but not in HAoECs, whilst the pro-migratory effect of PMA in ECFCs was potentiated after Nox4 knockdown (control siRNA 53.4±3.5, +PMA 61.5±3.2% closure; n=3, P=NS; Nox4 siRNA 35.1±4.9, +PMA 53.0±4.9% closure; n=3, P<0.05). Conclusion. ECFC migration is enhanced by low concentrations of superoxide, to a greater extent compared to mature endothelial cells, and appears to be at least partly dependent upon NADPH oxidase, including a specific role for Nox4. Although, the precise contribution of endothelial Nox NADPH oxidases isoforms remains to be determined, it is clear that these findings may have significant implications for potential ECFC-based therapies for ischaemic disease, which is associated with an oxidative microenvironment.

From 'trailing wives' to the emergence of a 'trailing husbands' phenomenon: Retirement migration to rural areas

Migration and gender studies have focused on economically active heterogeneous couples and traditionally highlight a dominant male role in migration decision-making. The female partner is commonly portrayed as a 'trailing wife' or 'trailing mother' with the move found to have a negative effect on her employment prospects. Much less is known about if or how the balance of power shifts between husbands and wives when employment or career-motivated moves are removed from the decision-making process. This is analysed with reference to retirement migration to rural areas of the UK and involved interviews with both partners present. For this cohort of retired couples, and in common with the literature, migration during economically active life course stages demonstrates strong 'trailing wife' and 'trailing mother' tendencies. The male's decision to retire signalled the commencement of a retirement life course stage for the couple. However, in contrast to the earlier male dominated decision-making, retirement migration saw the emergence of a 'trailing husband' phenomenon. Wives appear to adapt most successfully to the new rural environment while many husbands found it difficult to adjust (at least initially) to the multiple life changes: moving from largely urban areas to a rural setting alongside exiting the workforce. The findings suggest that the role of leader/ follower changed during the course of these couples' lives together and in relation to their reasons for moving.

Is Longer-Distance Migration Slowing? An Analysis of the Annual Record for England and Wales since the 1970s

This paper is prompted by the widespread acceptance that the rates of inter-county and inter-state migration have been falling in the USA and sets itself the task of examining whether this decline in migration intensities is also the case in the UK. It uses annual inter-area migration matrices available for England and Wales since the 1970s by broad age group. The main methodological challenge, arising from changes in the geography of health areas for which the inter-area flows are given, is addressed by adopting the lowest common denominator of 80 areas. Care is also taken to allow for the effect of economic cycles in producing short-term fluctuations on migration rates and to isolate the effect of a sharp rise in rates for 16-24 year olds in the 1990s, which is presumed to be related to the expansion of higher education. The findings suggest that, unlike for the USA, there has not been a substantial decline in the intensity of internal migration between the first two decades of the study period and the second two. If there has been any major decline in the intensity of address changing in England and Wales, it can only be for the within-area moves that this time series does not cover. This latter possibility is examined in a companion paper using a very different data set (Champion and Shuttleworth, 2016).

Are People Changing Address Less? An Analysis of Migration within England and Wales, 1971–2011, by Distance of Move

Expectations of migration and mobility steadily increasing in the longer term, which have a long currency in migration theory and related social science, are at odds with the latest US research showing a marked decline in internal migration rates. This paper reports the results of research that investigates whether England and Wales have experienced any similar change in recent decades. Using the Office for National Statistics Longitudinal Study (ONS-LS) of linked census records, it examines the evidence provided by its 10-year migration indicator, with particular attention to a comparison of the first and latest decades available, 1971-1981 and 2001-2011. This suggests that, as in the USA, there has been a marked reduction in the level of shorter-distance (less than 10km) moving that has involved almost all types of people. In contrast to this and to US experience, however, the propensity of people to make longer-distance address changes between decennial censuses has declined much less, largely corroborating the results of a companion study tracking the annual trend in rates of between-area migration since the 1970s (Champion and Shuttleworth, 2016).

A comparison of gold nanoparticle surface co-functionalization approaches using Polyethylene Glycol (PEG) and the effect on stability, non-specific protein adsorption and internalization

To create clinically useful gold nanoparticle (AuNP) based cancer therapeutics it is necessary to co-functionalize the AuNP surface with a range of moieties; e.g. Polyethylene Glycol (PEG), peptides and drugs. AuNPs can be functionalized by creating either a mixed monolayer by attaching all the moieties directly to the surface using thiol chemistry, or by binding groups to the surface by means of a bifunctional polyethylene glycol (PEG) linker. The linker methodology has the potential to enhance bioavailability and the amount of functional agent that can be attached. While there is a large body of published work using both surface arrangements independently, the impact of attachment methodology on stability, non-specific protein adsorption and cellular uptake is not well understood, with no published studies directly comparing the two most frequently employed approaches. This paper compares the two methodologies by synthesizing and characterizing PEG and Receptor Mediated Endocytosis (RME) peptide co-functionalized AuNPs prepared using both the mixed monolayer and linker approaches. Successful attachment of both PEG and RME peptide using the two methods was confirmed using Dynamic Light Scattering, Fourier Transform Infrared Spectroscopy and gel electrophoresis. It was observed that while the 'as synthesized' citrate capped AuNPs agglomerated under physiological salt conditions, all the mixed monolayer and PEG linker capped samples remained stable at 1M NaCl, and were stable in PBS over extended periods. While it was noted that both functionalization methods inhibited non-specific protein attachment, the mixed monolayer samples did show some changes in gel electrophoresis migration profile after incubation with fetal calf serum. PEG renders the AuNP stable in-vivo however, studies with MDA-MB-231 and MCF 10A cell lines indicated that functionalization with PEG, blocks cellular uptake. It was observed that co-functionalization with RME peptide using both the mixed monolayer and PEG linker methods greatly enhanced cellular internalization compared to PEG capped AuNPs.

ALMA-resolved salt emission traces the chemical footprint and inner wind morphology of VY Canis Majoris

(abreviated) We aim to study the inner-wind structure (R<250 Rstar) of the well-known red supergiant VY CMa. We analyse high spatial resolution (~0".24x0".13) ALMA Science Verification (SV) data in band 7 in which four thermal emission lines of gaseous sodium chloride (NaCl) are present at high signal-to-noise ratio. For the first time, the NaCl emission in the inner wind region of VY CMa is spatially resolved. The ALMA observations reveal the contribution of up to four different spatial regions. The NaCl emission pattern is different compared to the dust continuum and TiO2 emission already analysed from the ALMA SV data. The emission can be reconciled with an axisymmetric geometry, where the lower density polar/rotation axis has a position angle of ~50 degrees measured from north to east. However, this picture can not capture the full morphological diversity, and discrete mass ejection events need to be invoked to explain localized higher-density regions. The velocity traced by the gaseous NaCl line profiles is significantly lower than the average wind terminal velocity, and much slower than some of the fastest mass ejections, signalling a wide range of characteristic speeds for the mass loss. Gaseous NaCl is detected far beyond the main dust condensation region. Realising the refractory nature of this metal halide, this hints at a chemical process preventing all NaCl from condensing onto dust grains. We show that in the case of the ratio of the surface binding temperature to the grain temperature being ~50, only some 10% of NaCl remains in gaseous form, while for lower values of this ratio thermal desorption efficiently evaporates NaCl. Photodesorption by stellar photons seems not to be a viable explanation for the detection of gaseous NaCl at 220 Rstar from the central star, and instead, we propose shock-induced sputtering driven by localized mass ejection events as alternative.