The College of Radiographers Research Strategy for the next five years.

This article outlines the updated College of Radiographers (CoR) Research Strategy. This new research strategy will shape the approach to research from the radiography profession over the next five years. This will apply to all the profession and is aspirational and future thinking. The updated research strategy is the fifth research strategy presented by the CoR. Over the last five years, there have been considerable developments within healthcare and healthcare research. As this article is being written we are still in the middle of a global pandemic (Covid-19) which has influenced all our lives. However, despite the challenges of the last year, we are in a stronger position as a profession with more radiographers working towards and gaining masters and doctoral level qualifications. There are more radiographers working in clinical academic roles and there has been further development of radiographers coordinating and delivering research as well as becoming research leaders. This updated research strategy supports the radiography profession in delivering research-based practice over the next five years offering a framework within which radiographers can develop.

Apical membrane targeting of Nedd4 is mediated by an association of its C2 domain with annexin XIIIb.

Nedd4 is a ubiquitin protein ligase (E3) containing a C2 domain, three or four WW domains, and a ubiquitin ligase HECT domain. We have shown previously that the C2 domain of Nedd4 is responsible for its Ca(2+)-dependent targeting to the plasma membrane, particularly the apical region of epithelial MDCK cells. To investigate this apical preference, we searched for Nedd4-C2 domain-interacting proteins that might be involved in targeting Nedd4 to the apical surface. Using immobilized Nedd4-C2 domain to trap interacting proteins from MDCK cell lysate, we isolated, in the presence of Ca(2+), a approximately 35-40-kD protein that we identified as annexin XIII using mass spectrometry. Annexin XIII has two known isoforms, a and b, that are apically localized, although XIIIa is also found in the basolateral compartment. In vitro binding and coprecipitation experiments showed that the Nedd4-C2 domain interacts with both annexin XIIIa and b in the presence of Ca(2+), and the interaction is direct and optimal at 1 microM Ca(2+). Immunofluorescence and immunogold electron microscopy revealed colocalization of Nedd4 and annexin XIIIb in apical carriers and at the apical plasma membrane. Moreover, we show that Nedd4 associates with raft lipid microdomains in a Ca(2+)-dependent manner, as determined by detergent extraction and floatation assays. These results suggest that the apical membrane localization of Nedd4 is mediated by an association of its C2 domain with the apically targeted annexin XIIIb.

Non-invasive ventilation in chronic obstructive pulmonary disease: management of acute type 2 respiratory failure.

Non-invasive ventilation (NIV) in the management of acute type 2 respiratory failure in patients with chronic obstructive pulmonary disease (COPD) represents one of the major technical advances in respiratory care over the last decade. This document updates the 2002 British Thoracic Society guidance and provides a specific focus on the use of NIV in COPD patients with acute type 2 respiratory failure. While there are a variety of ventilator units available most centres now use bi-level positive airways pressure units and this guideline refers specifically to this form of ventilatory support although many of the principles encompassed are applicable to other forms of NIV. The guideline has been produced for the clinician caring for COPD patients in the emergency and ward areas of acute hospitals.

Latent membrane protein 2A of Epstein-Barr virus binds WW domain E3 protein-ubiquitin ligases that ubiquitinate B-cell tyrosine kinases.

The latent membrane protein (LMP) 2A of Epstein-Barr virus (EBV) is implicated in the maintenance of viral latency and appears to function in part by inhibiting B-cell receptor (BCR) signaling. The N-terminal cytoplasmic region of LMP2A has multiple tyrosine residues that upon phosphorylation bind the SH2 domains of the Syk tyrosine kinase and the Src family kinase Lyn. The LMP2A N-terminal region also has two conserved PPPPY motifs. Here we show that the PPPPY motifs of LMP2A bind multiple WW domains of E3 protein-ubiquitin ligases of the Nedd4 family, including AIP4 and KIAA0439, and demonstrate that AIP4 and KIAA0439 form physiological complexes with LMP2A in EBV-positive B cells. In addition to a C2 domain and four WW domains, these proteins have a C-terminal Hect catalytic domain implicated in the ubiquitination of target proteins. LMP2A enhances Lyn and Syk ubiquitination in vivo in a fashion that depends on the activity of Nedd4 family members and correlates with destabilization of the Lyn tyrosine kinase. These results suggest that LMP2A serves as a molecular scaffold to recruit both B-cell tyrosine kinases and C2/WW/Hect domain E3 protein-ubiquitin ligases. This may promote Lyn and Syk ubiquitination in a fashion that contributes to a block in B-cell signaling. LMP2A may potentiate a normal mechanism by which Nedd4 family E3 enzymes regulate B-cell signaling.

Serum stimulation of plasma protein synthesis in culture is selective and rapidly reversible.

Primary hepatocyte monolayers, derived from chick embryos, can be cultured from the onset in a completely chemically defined medium, free of added hormones. The liver cells synthesize and secrete a wide spectrum of plasma proteins for several days in this serum-free environment. Addition of fetal bovine serum elicits a 3-5-fold increase in the production of certain plasma proteins: fibrinogen, albumin, and the alpha1-globulin M. This effect of serum is selective; transferrin and plasminogen syntheses are enhanced less than 1.5-fold. Significant stimulation is observed with 0.1% fetal bovine serum, and half-maximal values for individual plasma proteins are obtained with concentrations ranging between 0.4 and 1%. The stimulatory activity of serum shows no developmental or species specificity. Plasma is active as serum derived from the same blood sample. The hepatocytes respond rapidly to serum, significant changes in albumin synthesis occurring less than 1 h after serum addition or removal. The effect of short exposure is fully reversible. These results establish the capacity of low concentrations of serum to stimulate plasma protein synthesis and underscore the importance of studying the effects of hormones and other factors under serum-free conditions. The findings suggest that, in addition to the classical hormones, ubiquitous but as yet uncharacterized serum components play a role in controlling this major hepatic function.

Structural analysis of fibrinogen synthesized by cultured chicken hepatocytes in the presence or absence of dexamethasone.

Hepatocyte monolayers, derived from chick embryos and cultured in chemically defined medium without hormones, synthesize and secrete fibrinogen that resembles chicken plasma fibrinogen immunochemically and structurally. Addition of a synthetic glucocorticoid, dexamethasone, to the cultured cells resulted in an appreciable and relatively selective increase in fibrinogen synthesis. Autoradiography of fibrinogen that had been metabolically labelled with [35S]methionine and then subjected to SDS-polyacrylamide gel electrophoresis, unreduced or under disulfide-reducing conditions, revealed that only dimeric forms of fibrinogen, containing undegraded A alpha, B beta, and gamma chains, were secreted under stimulated and unstimulated culture conditions.

Hormonal regulation of fibrinogen synthesis in cultured hepatocytes.

Most of what was originally known of the effects of hormones on fibrinogen synthesis was based, as noted above, on experiments involving surgical removal of endocrine glands. Some caution should be exercised when using such in vivo experiments to derive the hormonal requirements of fibrinogen synthesis, however, since multiple hormonal alterations often occur in these animals. The development of a variety of ex vivo systems has allowed investigators to more carefully control the hepatocellular environment. The work of several laboratories, including our own, has now made it clear that hormones and other agents directly stimulate hepatocellular synthesis of fibrinogen. From the studies summarized here, using chick embryo hepatocytes as a model, several generalizations emerge: Fibrinogen synthesis may be considered to be a "constitutive" liver function, since hepatocytes cultured without serum, hormones or other macromolecular supplements synthesize this protein at a basal rate for several days. Addition of certain hormones (e.g. T3, dexamethasone, insulin), individually and in physiological concentrations, elicits an increase in fibrinogen production, varying with each agent in onset, dose, minimum exposure required and accompanying effects on the synthesis of other plasma proteins. Glucocorticoids and thyroid hormones are similar in the selectivity of their stimulation (neither affects albumin or transferrin synthesis) but differ in that thyroid hormones need to be present for just a short "triggering" period. The stimulation of fibrinogen synthesis by insulin occurs only following prolonged exposure to concentrations 10-times higher than the very low doses to which albumin synthesis responds rapidly.

The relative lung and systemic bioavailability of terbutaline following nebulisation in non-invasively ventilated patients.

Nebulising a bronchodilator during non-invasive ventilation (NIV) is effective but there is a lack of consensus on the system to use because comparator in vivo studies in these patients are difficult. Urinary pharmacokinetic methodology post inhalation could provide this information. Chronic obstructive pulmonary disease patients requiring NIV received randomised study doses of either 2mg terbutaline nebulised from an Aeroneb Pro (AERO) or 5mg from a Sidestream (SIDE) on days 1 and 3 of admission. Urine samples were provided at 30 min then pooled up to 24h post inhalation and amounts of urinary terbutaline (UTER0.5 and UTER24; indices of relative lung and systemic bioavailability, respectively) were determined. Twelve consenting patients receiving NIV mean (SD) age and weight of 74.8 (8.2) years and 61.0 (10.7)kg completed the study. The mean (SD) UTER0.5 following AERO and SIDE was 9.4 (3.7) and 10.4 (4.1) µg with a mean ratio (90% confidence interval) of 89.7 (87.8, 92.3)%. UTER24 was 192.3 (52.4) and 205.3 (58.0)mcg with a mean ratio (90% CI) of 93.7 (113.5, 77.3)%. This urinary pharmacokinetic method to identity relative lung and systemic bioavailability between two nebuliser systems was easy to perform and is a useful and simple in vivo method to compare different nebulisers in patients receiving non-invasive ventilation.

Use of the Nottingham Health Profile to test the validity of census variables to proxy the need for health care.

BACKGROUND: Data on health or health service use are invariably used to test the validity of proxy measures of need, for use in resource allocation formulae. Perceived health state is a good measure to use in this respect, as it is closely linked to perceived need and the decision to consult health services. This being the case, a large community based study was undertaken which collected data on perceived health, using the Nottingham Health Profile (NHP), with the aim of testing the validity of a variety of Census based measures as proxy measures of the need for health care. METHOD: A postal questionnaire survey of 9565 people living in the former South East Thames Regional Health Authority was conducted and the relationship between their perceived health state and the socio-economic characteristics of their electoral ward of residence analysed. RESULTS: A relatively low response rate (59 per cent) weakened any conclusions to be drawn from the results. However, significant correlations between perceived health and a variety of the Census based indicators were found. The highly skewed distribution of responses to the NHP statements made the results difficult to analyse and interpret. CONCLUSIONS: Although the study gave an indication of those variables that might be incorporated into resource allocation formulae, the NHP is not a particularly efficient instrument to use in a community setting. It is argued that the appropriateness of an approach to determining appropriate needs weights in allocation formulae, which attempts to find one indicator of all health care needs at the District Health Authority level, must be questioned.

Chronic obstructive pulmonary disease * 9: management of ventilatory failure in COPD.

The management of respiratory failure during acute exacerbations of COPD and during chronic stable COPD is reviewed and the role of non-invasive and invasive mechanical ventilation is discussed.

Noncoordinate synthesis of the fibrinogen subunits in hepatocytes cultured under hormone-deficient conditions.

Differential detergent gel electrophoresis conditions are described which enable the accurate quantitation of radiolabel incorporated into each of the closely migrating, constituent polypeptides of chicken fibrinogen: glycosylated and nonglycosylated A alpha, B beta, gamma', and gamma. These methods were applied to analysis of fibrinogen synthesis by monolayer cultures of chick embryo hepatocytes to determine whether the cells coordinate biosynthesis of the fibrinogen subunits under nonstimulated or basal conditions (i.e. in the absence of hormones) and in the presence of serum, which is a potent stimulator of fibrinogen production. Since secretion of the subunits apparently depends on their oligomeric assembly into the general structure (A alpha, B beta, gamma)2, it was thought that their synthesis might be stoichiometric. Incorporation of [35S]methionine into the subunit chains was determined for both cellular and secreted fibrinogen, immunoprecipitated from pulse-labeled and continuously labeled cultures. Molar ratios of subunit synthesis and the degree of serum-induced stimulation for each subunit were calculated. Specific subunit mRNA levels were also evaluated with a cell-free translation assay as well as microinjection of RNA into Xenopus oocytes. The results indicate, to the contrary, that in hormone-deprived hepatocytes there is a deficiency in A alpha chain synthesis, correlating with reduced A alpha-specific mRNA levels, which leads to hepatocellular degradation of surplus B beta and gamma chains. Addition of serum to the cellular environment, while increasing rates of subunit synthesis, also corrects the deficiency in A alpha chain synthesis, thereby restoring a measure of balance and preventing much of the degradation. The outcome of this serum-induced enhancement and coordination of fibrinogen subunit gene expression is a dramatic (more than 20-fold) stimulation of fibrinogen secretion.

Non-invasive positive pressure ventilation.

NPPV is a major advance in respiratory and critical care medicine. In the acute setting, it has a clear role in the management of patients with COPD who are acidotic, and in weaning from IMV. NPPV in hypoxic RF shows promise for selected patients, but further studies are required. For domiciliary use, NPPV is effective in both the short and long term for the management of extrapulmonary restrictive disease, but further research is required for COPD.

Selective block of albumin gene expression in chick embryo hepatocytes cultured without hormones and its partial reversal by insulin.

Rates of synthesis of albumin and transferrin were compared with the levels of their cognate mRNAs in primary monolayer cultures of chick embryo hepatocytes over a period of 72 h. These liver cells were exposed, from the onset of culture, only to a chemically defined medium devoid of hormonal or macromolecular supplement. Synthesis of transferrin was constant whereas synthesis of albumin diminished to near 0 in 3 days. RNA prepared from hepatocyte monolayers, maintained for various lengths of time in culture, was translated in wheat germ extracts and Xenopus oocytes. Translation products were immunoprecipitated and analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. In addition, total RNA from the cultured cells was hybridized to labeled cDNA probes to determine the number of sequences specific for each protein. Albumin mRNA was found to decrease with time in culture in all three assay systems, while transferrin mRNA remained constant. Analysis of the kinetics suggests a selective decay, with a half-life of 7 h, of the amount of albumin-specific RNA present at the beginning of culture. Apparently, in the hormone-deprived hepatocytes, there is little or no further transcription of the albumin gene. After addition of insulin to the cultures, albumin mRNA levels increased, suggesting an effect of this hormone on albumin gene utilization.

Glycosylated A alpha chains in chicken fibrinogen.

Fibrinogen immunoprecipitated from cultured chick embryo hepatocytes was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and compared with fibrinogen from chicken plasma. The character and relatedness of the constituent polypeptide bands were established on the basis of enzymatic treatment, peptide analysis, metabolic labeling with [14C]glucosamine, and inhibition of glycosylation with tunicamycin. Hepatocyte-derived fibrinogen resolved into five polypeptides that, in order of decreasing apparent molecular weight, were identified as glycosylated A alpha, non-glycosylated A alpha, B beta, gamma', and gamma. Fibrinogen immunoprecipitated directly from chicken plasma yielded an identical profile except for an additional smaller A alpha chain. This small A alpha chain appears to be the product of partial proteolysis in the circulation and was the only A alpha band found in purified plasma fibrinogen (fraction I-2). The observation of glycosylated A alpha chains is novel. The gamma/gamma' chain heterogeneity appears to be due to an amino acid extension similar to that observed in mammalian fibrinogens. Fibrinogen from cells exposed to fetal bovine serum, a potent stimulator of fibrinogen production, was enriched in glycosylated A alpha chains, which constituted approximately one-third of the A alpha chain population. Serum did not affect the gamma/gamma' chain distribution.

Selective intracellular degradation of fibrinogen and its reversal in cultured hepatocytes.

Primary monolayer cultures of chick embryo hepatocytes were employed in pulse-chase experiments to examine plasma protein synthesis and secretion. The fates of [35S]methionine-labeled fibrinogen and transferrin were monitored in cell extracts and in spent culture media. It was found that hepatocytes, which were maintained in the absence of added hormones or serum, released into the medium virtually all of the label of transferrin but only 30% of the label in fibrinogen. The remainder of the labeled fibrinogen was retained by the cells, gradually disappearing in a manner suggestive of its intracellular degradation. To stimulate fibrinogen production on as many levels as possible, fetal bovine serum was added to the medium of the cultured cells. Serum elicited an increase in the level of fibrinogen mRNA which was accompanied by a 7-fold increase in the rate of fibrinogen synthesis as well as the complete release of fibrinogen label, resulting in an overall 20-fold enhancement in the hepatocellular output of this protein. Thus, both the amount of fibrinogen synthesized as well as the amount ultimately secreted are subject to modulation by the hepatocellular environment.