Ultrasound-guided percutaneous delivery of tissue-engineered endothelial cells to the adventitia of stented arteries controls the response to vascular injury in a porcine model

Objective High restenosis rates are a limitation of peripheral vascular interventions. Previous studies have shown that surgical implantation of a tissue-engineered endothelium onto the adventitia surface of injured vessels regulates vascular repair. In the present study, we developed a particulate formulation of tissue-engineered endothelium and a method to deliver the formulation perivascular to injured blood vessels using a percutaneous, minimally invasive technique. Methods Stainless steel stents were implanted in 18 balloon-injured femoral arteries of nine domestic swine, followed by ultrasound-guided percutaneous perivascular injection of gelatin particles containing cultured allogeneic porcine aortic endothelial cells (PAE). Controls received injections of empty particles (matrix) or no perivascular injection (sham) after stent deployment. Animals were sacrificed after 90 days. Results Angiographic analysis revealed a significantly greater lumen diameter in the stented segments of arteries treated with PAE/matrix (4.72 ± 0.12 mm) compared with matrix (4.01 ± 0.20 mm) or sham (4.03 ± 0.16 mm) controls (P < .05). Similarly, histologic analysis revealed that PAE/matrix-treated arteries had the greatest lumen area (20.4 ± 0.7 mm[superscript 2]; P < .05) compared with controls (16.1 ± 0.9 mm[superscript 2] and 17.1 ± 1.0 mm[superscript 2] for sham and matrix controls, respectively) and the smallest intimal area (3.3 ± 0.4 mm[superscript 2]; P < .05) compared with controls (6.2 ± 0.5 mm[superscript 2] and 4.4 ± 0.5 mm[superscript 2] for sham and matrix controls, respectively). Overall, PAE-treated arteries had a 33% to 50% decrease in percent occlusion (P < .05) compared with controls. Histopathological analysis revealed fewer leukocytes present in the intima in the PAE/matrix group compared with control groups, suggesting that the biological effects were in part due to inhibition of the inflammatory phase of the vascular response to injury. Conclusions Minimally invasive, perivascular delivery of PAE/matrix to stented arteries was performed safely using ultrasound-guided percutaneous injections and significantly decreased stenosis. Application at the time of or subsequent to peripheral interventions may decrease clinical restenosis rates

Delivery Site of Perivascular Endothelial Cell Matrices Determines Control of Stenosis in a Porcine Femoral Stent Model

PURPOSE: High restenosis rates are a major limitation of peripheral interventions. Endothelial cells, grown within gelatin matrices and implanted onto the adventitia of injured vessels, inhibit stenosis in experimental models. To determine if this technology could be adapted for minimally invasive procedures, we compared the effects of cells in an implantable sponge to an injectable formulation and investigated the importance of delivery site in a stent model. MATERIALS AND METHODS: Stents were implanted in the femoral arteries of 30 pigs followed by perivascular implantation of sponges or injection of particles containing allogeneic endothelial cells. Controls received acellular matrices or nothing. The effects of delivery site were assessed by injecting cellular matrices into or adjacent to the perivascular tissue, or into the neighboring muscle. Animals were sacrificed after 28 days. Pre-sacrifice angiograms and tissue sections were evaluated for stenosis. RESULTS: Arteries treated with cellular matrices had a 55 – 63% decrease in angiographic stenosis (P<0.05) and a 38 – 43% reduction (P<0.05) in histologic stenoses compared to controls. Intimal area was greatest when cellular matrices were delivered into the muscle (6.35 ± 0.95 mm2) compared to into or adjacent to the perivascular tissue (4.05 ± 0.56 mm2 and 4.73 ± 0.53 mm2, respectively, P < 0.05). CONCLUSIONS: Perivascular endothelial-cell matrices reduced stenosis after stent-induced injury. The effects were not dependent on the formulation but appeared to be dependent upon delivery site. Minimally invasive injections of endothelial-cell matrices to the adventitia of arteries following peripheral interventions may decrease restenosis rates.National Institutes of Health (U.S.) (Grant GM 49039

Crops, Rumps and Woolly Jumpers: An Innovative Extension Approach Enabling the Complexities of Mixed Farming to Be Shared and Understood

The sheep-wheat belt of southern Australia accounts for about 19% and 57% of total Australian beef and sheep production, respectively. Most farm businesses in this zone are family owned and contain a mix of livestock and cropping enterprises. While the focus of most research, development and extension for mixed farming systems focuses on single components of the system (lamb, wool, beef, pastures, crops), the systems are complex and dynamic and cannot be understood by analysing the components in isolation. The enterprise synergies are dependent on economic, environmental and social factors. The farmers themselves are best equipped to explain the system function and the interplay between the components. The traditional conference format with technical experts presenting their findings was deemed to be inadequate to relay the complexity of mixed farming systems, stifling two-way information flow and the opportunity for experts to acquire tacit knowledge held by farmers. This paper out-lines an innovative extension approach based on story telling, video footage and discussion, providing technical experts with an opportunity to appreciate the complexity and farmer decision processes. This approach fostered audience participation and interaction, leading to a better understanding of the complexities of mixed farming and how conflicts between diversification and specialisation may be resolved by the management team. Facilitated discussion also highlighted potential areas of research, development and extension

Downstream effects on human low density lipoprotein of homocysteine exported from endothelial cells in an in vitro system

A model system is presented using human umbilical vein endothelial cells (HUVECs) to investigate the role of homocysteine (Hcy) in atherosclerosis. HUVECs are shown to export Hcy at a rate determined by the flux through the methionine/Hcy pathway. Additional methionine increases intracellular methionine, decreases intracellular folate, and increases Hcy export, whereas additional folate inhibits export. An inverse relationship exists between intracellular folate and Hcy export. Hcy export may be regulated by intracellular S-adenosyl methionine rather than by Hcy. Human LDLs exposed to HUVECs exporting Hcy undergo time-related lipid oxidation, a process inhibited by the thiol trap dithionitrobenzoate. This is likely to be related to the generation of hydroxyl radicals, which we show are associated with Hcy export. Although Hcy is the major oxidant, cysteine also contributes, as shown by the effect of glutamate. Finally, the LDL oxidized in this system showed a time-dependent increase in uptake by human macrophages, implying an upregulation of the scavenger receptor. These results suggest that continuous export of Hcy from endothelial cells contributes to the generation of extracellular hydroxyl radicals, with associated oxidative modification of LDL and incorporation into macrophages, a key step in atherosclerosis. Factors that regulate intracellular Hcy metabolism modulate these effects. Copyright © 2005 by the American Society for Biochemistry and Molecular Biology, Inc

Validity of a three-variable juvenile arthritis disease activity score in children with new-onset juvenile idiopathic arthritis

&lt;p&gt;Objectives To investigate the validity and feasibility of the Juvenile Arthritis Disease Activity Score (JADAS) in the routine clinical setting for all juvenile idiopathic arthritis (JIA) disease categories and explore whether exclusion of the erythrocyte sedimentation rate (ESR) from JADAS (the ‘JADAS3’) influences correlation with single markers of disease activity.&lt;/p&gt; &lt;p&gt;Methods JADAS-71, JADAS-27 and JADAS-10 were determined at baseline for an inception cohort of children with JIA in the Childhood Arthritis Prospective Study. JADAS3-71, JADAS3-27 and JADAS3-10 were determined using an identical formula but with exclusion of ESR. Correlation of JADAS with JADAS3 and single measures of disease activity/severity were determined by category.&lt;/p&gt; &lt;p&gt;Results Of 956 eligible children, sufficient data were available to calculate JADAS-71, JADAS-27 and JADAS-10 at baseline in 352 (37%) and JADAS3 in 551 (58%). The median (IQR) JADAS-71, JADAS-27 and JADAS-10 for all 352 children was 11 (5.9–18), 10.4 (5.7–17) and 11 (5.9–17.3), respectively. Median JADAS and JADAS3 varied significantly with the category (Kruskal–Wallis p=0.0001), with the highest values in children with polyarticular disease patterns. Correlation of JADAS and JADAS3 across all categories was excellent. Correlation of JADAS71 with single markers of disease activity/severity was good to moderate, with some variation across the categories. With the exception of ESR, correlation of JADAS3-71 was similar to correlation of JADAS-71 with the same indices.&lt;/p&gt; &lt;p&gt;Conclusions This study is the first to apply JADAS to all categories of JIA in a routine clinical setting in the UK, adding further information about the feasibility and construct validity of JADAS. For the majority of categories, clinical applicability would be improved by exclusion of the ESR.&lt;/p&gt

A modelling approach to investigate the impact of consumption of three different beef compositions on human dietary fat intakes

Objective: To apply a dietary modelling approach to investigate the impact of substituting beef intakes with three types of alternative fatty acid (FA) composition of beef on population dietary fat intakes. Design: Cross-sectional, national food consumption survey – the National Adult Nutrition Survey (NANS). The fat content of the beef-containing food codes (n 52) and recipes (n 99) were updated with FA composition data from beef from animals receiving one of three ruminant dietary interventions: grass-fed (GRASS), grass finished on grass silage and concentrates (GSC) or concentrate-fed (CONC). Mean daily fat intakes, adherence to dietary guidelines and the impact of altering beef FA composition on dietary fat sources were characterised. Setting: Ireland. Participants: Beef consumers (n 1044) aged 18–90 years. Results: Grass-based feeding practices improved dietary intakes of a number of individual FA, wherein myristic acid (C14 : 0) and palmitic acid (C16 : 0) were decreased, with an increase in conjugated linoleic acid (C18 : 2c9,t11) and trans-vaccenic acid (C18 : 1t11; P < 0·05). Improved adherence with dietary recommendations for total fat (98·5 %), SFA (57·4 %) and PUFA (98·8 %) was observed in the grass-fed beef scenario (P < 0·001). Trans-fat intakes were increased significantly in the grass-fed beef scenario (P < 0·001). Conclusions: To the best of our knowledge, the present study is the first to characterise the impact of grass-fed beef consumption at population level. The study suggests that habitual consumption of grass-fed beef may have potential as a public health strategy to improve dietary fat quality

Severe Airway Epithelial Injury, Aberrant Repair and Bronchiolitis Obliterans Develops after Diacetyl Instillation in Rats

Bronchiolitis obliterans (BO) is a fibrotic lung disease that occurs in a variety of clinical settings, including toxin exposures, autoimmunity and lung or bone marrow transplant. Despite its increasing clinical importance, little is known regarding the underlying disease mechanisms due to a lack of adequate small animal BO models. Recent epidemiological studies have implicated exposure to diacetyl (DA), a volatile component of artificial butter flavoring, as a cause of BO in otherwise healthy factory workers. Our overall hypothesis is that DA induces severe epithelial injury and aberrant repair that leads to the development of BO. Therefore, the objectives of this study were 1) to determine if DA, delivered by intratracheal instillation (ITI), would lead to the development of BO in rats and 2) to characterize epithelial regeneration and matrix repair after ITI of DA.Male Sprague-Dawley rats were treated with a single dose of DA (125 mg/kg) or sterile water (vehicle control) by ITI. Instilled DA resulted in airway specific injury, followed by rapid epithelial regeneration, and extensive intraluminal airway fibrosis characteristic of BO. Increased airway resistance and lung fluid neutrophilia occurred with the development of BO, similar to human disease. Despite rapid epithelial regeneration after DA treatment, expression of the normal phenotypic markers, Clara cell secretory protein and acetylated tubulin, were diminished. In contrast, expression of the matrix component Tenascin C was significantly increased, particularly evident within the BO lesions.We have established that ITI of DA results in BO, creating a novel chemical-induced animal model that replicates histological, biological and physiological features of the human disease. Furthermore, we demonstrate that dysregulated epithelial repair and excessive matrix Tenacin C deposition occur in BO, providing new insights into potential disease mechanisms and therapeutic targets

Costs and effects of a 'healthy living' approach to community development in two deprived communities: findings from a mixed methods study

Background: Inequalities in health have proved resistant to 'top down' approaches. It is increasingly recognised that health promotion initiatives are unlikely to succeed without strong local involvement at all stages of the process and many programmes now use grass roots approaches. A healthy living approach to community development (HLA) was developed as an innovative response to local concerns about a lack of appropriate services in two deprived communities in Pembrokeshire, West Wales. We sought to assess feasibility, costs, benefits and working relationships of this HLA. Methods: The HLA intervention operated through existing community forums and focused on the whole community and its relationship with statutory and voluntary sectors. Local people were trained as community researchers and gathered views about local needs though resident interviews. Forums used interview results to write action plans, disseminated to commissioning organisations. The process was supported throughout through the project. The evaluation used a multi-method before and after study design including process and outcome formative and summative evaluation; data gathered through documentary evidence, diaries and reflective accounts, semi-structured interviews, focus groups and costing proformas. Main outcome measures were processes and timelines of implementation of HLA; self reported impact on communities and participants; community-agency processes of liaison; costs. Results: Communities were able to produce and disseminate action plans based on locally-identified needs. The process was slower than anticipated: few community changes had occurred but expectations were high. Community participants gained skills and confidence. Cross-sector partnership working developed. The process had credibility within service provider organisations but mechanisms for refocusing commissioning were patchy. Intervention costs averaged £58,304 per community per annum. Conclusions: The intervention was feasible and inexpensive, with indications of potential impact at individual, community and policy planning levels. However, it is a long term process which requires sustained investment and must be embedded in planning and service delivery processes.12 page(s

Associations between DSM-IV diagnosis, psychiatric symptoms and morning cortisol levels in a community sample of adolescents

Purpose. Dysfunction of the hypothalamic-pituitary-adrenocortical axis (HPA-axis) is implicated in a variety of psychiatric and emotional disorders. In this study, we explore the association between HPA-axis functioning, as measured by morning cortisol, and common psychiatric disorders and symptoms among a community sample of adolescents. Method. Data from a cross-sectional school-based survey of 501 school pupils, aged 15, were used to establish the strength of association between salivary morning cortisol and both diagnosis of psychiatric disorders and a number of psychiatric symptoms, as measured via a computerised psychiatric interview. Analysis, conducted separately by gender, used multiple regressions, adjusting for relevant confounders. Results-á-áWith one exception (a positive association between conduct disorder symptoms and cortisol among females) there was no association between morning cortisol and psychiatric diagnosis or symptoms. However, there was a significant two-way interaction between gender and conduct symptoms, with females showing a positive and males a negative association between cortisol and conduct symptoms. A further three-way interaction showed that while the association between cortisol and conduct symptoms was negative among males with a few mood disorder symptoms, among females with many mood symptoms it was positive. Conclusions. Except in relation to conduct symptoms, dysregulation of morning cortisol levels seems unrelated to any psychiatric disorder or symptoms. However, the relationship between cortisol and conduct symptoms is moderated by both gender and mood symptoms. Findings are compatible with the recent work suggesting research should concentrate on the moderated associations between gender, internalising and externalising symptoms and cortisol, rather than any simple relationship