Hyaluronic acid as a macromolecular crowding agent for production of cell-derived matrices.

Cell-derived matrices (CDMs) provide an exogenous source of human extracellular matrix (ECM), with applications as cell delivery vehicles, substrate coatings for cell attachment and differentiation, and as biomaterial scaffolds. However, commercial application of CDMs has been hindered due to the prolonged culture time required for sufficient ECM accumulation. One approach to increasing matrix deposition in vitro is macromolecular crowding (MMC), which is a biophysical phenomenon that limits the diffusion of ECM precursor proteins, resulting in increased ECM accumulation at the cell layer. Hyaluronic acid (HA), a natural MMC highly expressed in vivo during fetal development, has been shown to play a role in ECM production, but has not been investigated as a macromolecule for increasing cell-mediated ECM deposition in vitro. In the current study, we hypothesized that HA can act as a MMC, and increase cell-mediated ECM production. Human dermal fibroblasts were cultured for 3, 7, or 14 days with 0%, 0.05%, or 0.5% high molecular weight HA. Ficoll 70/400 was used as a positive control. SDS-PAGE, Sircol, and hydroxyproline assays indicated that 0.05% HA-treated cultures had significantly higher mean collagen deposition at 14 days, whereas Ficoll 70/400-treated cultures had significantly lower collagen production compared to the HA and untreated controls. However, fluorescent immunostaining of ECM proteins and quantification of mean gray values did not indicate statistically significant differences in ECM production in HA or Ficoll 70/400-treated cultures compared to untreated controls. Raman imaging (a marker-free spectral imaging method) indicated that HA increased ECM deposition in human dermal fibroblasts. These results are consistent with decreases in CDM stiffness observed in Ficoll 70/400-treated cultures by atomic force microscopy. Overall, these results indicate that there are macromolecule- and cell type- dependent effects on matrix assembly, turnover, and stiffness in cell-derived matrices. STATEMENT OF SIGNIFICANCE: Cell-derived matrices (CDMs) are versatile biomaterials with many regenerative medicine applications, including as cell and drug delivery vehicles and scaffolds for wound healing and tissue regeneration. While CDMs have several advantages, their commercialization has been limited due to the prolonged culture time required to achieve CDM synthesis in vitro. In this study, we explored the use of hyaluronic acid (HA) as a macromolecular crowder in human fibroblast cell cultures to support production of CDM biomaterials. Successful application of macromolecular crowding will allow development of human cell-derived, xeno-free biomaterials that re-capitulate the native human tissue microenvironment.

One-year follow-up of the outcome of a randomized controlled trial of a home-based intervention programme for children with autism and developmental delay and their families.

INTRODUCTION: There is debate about the type and intensity of early childhood intervention that is most helpful for children with developmental problems. The aim of the study was to determine whether a home-based programme provided over 12 months resulted in sustained improvement in development and behaviour 12 months after the intervention ceased. The characteristics of the children and families who benefited most from the intervention were also studied. METHOD: Randomized controlled trial. Participants A total of 59 children, aged 3-5 years, attending two early childhood intervention centres in Melbourne, Australia. Intervention Half of the subjects received an additional home-based programme consisting of 40 weekly visits. MAIN OUTCOME MEASURES: Bayley Scales of Infant Development and Wechsler Preschool and Primary Scale of Intelligence Revised, Preschool Behaviour Checklist, Bayley Behaviour Rating Scale and Behaviour Screening Questionnaire. All tests administered pre-intervention, following the intervention and 12 months later. Secondary outcome measures Family stress, support and empowerment. RESULTS: Fifty-four children completed the assessments 12 months after conclusion of the intervention. Compared with the control group, improvement in aspects of cognitive development in the children who received the extra intervention was sustained 1 year later (P= 0.007) while significant behavioural differences post intervention were not. Analyses of the data by the Reliable Change Index indicated improvement of clinical significance occurred in non-verbal areas. In contrast to the control group who deteriorated, language skills in the intervention group remained stable. Improvements were significantly associated with higher stress in the families. CONCLUSION: Improvements following the provision of a home-based programme to preschool children with developmental disabilities were sustained 1 year later. Children from highly stressed families appeared to benefit most, reinforcing the importance of involving families in early childhood intervention programmes.

Determining the composition and benefit of the pre-hospital medical response team in the conflict setting.

AIM: To determine the optimal composition o f the pre-hospital medical response team (MERT) and the value of pre-hospital critical care interventions in a military setting, and specifically to determine both the benefit of including a doctor in the pre-hospital response team and the relevance of the time and distance to definitive care. METHOD: A comprehensive review of the literature incorporating a range of electronic search engines and hand searches of key journals. RESULTS: There was no level 1 evidence on which to base conclusions. The 15 most relevant articles were analysed in detail. There was one randomized controlled trial (level 2 evidence) that supports the inclusion of a doctor on MERT. Several cohort studies were identified that analysed the benefits of specific critical care interventions in the pre-hospital setting. CONCLUSIONS: A doctor with critical care skills deployed on the MERT is associated with improved survival in victims of major trauma. Specific critical care interventions including emergency endotracheal intubation and ventilation, and intercostal drainage are associated with improved survival and functional recovery in certain patients. These benefits appear to be more easily demonstrated for the rural and remote setting than for the urban setting.

The implantable cardioverter-defibrillator: postcode prescribing in the UK 1998-2002.

OBJECTIVE: To determine the rate of implantable cardioverter-defibrillator (ICD) implantation across the UK during the period 1998 to 2002. DESIGN: Observational self reporting with cross checking. SETTING: All ICD implanting centres coordinated by the National Pacemaker and ICD Database. PATIENTS: Every patient receiving an ICD in the UK from 1998 to 2002. MAIN OUTCOME MEASURES: Date of implantation and postcode of each ICD recipient during the study period. RESULTS: ICD implantation increased in the UK in the five year period studied but fell far short of the European average and national targets. Implantation rates varied greatly by region. CONCLUSIONS: The low rate of ICD implantation in the UK and the disparity between regions require further study to determine the barriers to this evidence based treatment.

Improving care for patients with acute coronary syndromes: initial results from the National Audit of Myocardial Infarction Project (MINAP).

OBJECTIVE: To describe the improvements in care that have followed the introduction of an electronic data entry and analysis system providing contemporary feedback on the management of acute coronary syndromes in 230 hospitals in England and Wales. DESIGN: Observational study METHODS: A secure electronic system was used to transfer encrypted data on patients with acute coronary syndromes from collaborating hospitals to central servers for analysis. Immediate online data entry to the central servers by hospitals allowed contemporary analyses of performance and immediate comparison with the national aggregate performance. RESULTS: The records of 156 902 patients receiving a final diagnosis of acute coronary syndrome during three years between October 2000 and September 2003 were analysed. Of 69 113 patients with ST segment elevation infarction, 75.4% received thrombolytic treatment. Between the first and last years of the study the median interval from hospital arrival to treatment fell for eligible patients from 38 (interquartile range 22-58) to 20 (interquartile range 14-28) minutes. By mid 2003 77.6% were receiving thrombolytic treatment within 30 minutes of arrival. The proportion treated within two hours of onset of symptoms increased from 32.5% to 40.3% (a difference of 7.8 percentage points, p < 0.0001). The use of secondary prevention medication for acute coronary syndromes increased over this period: angiotensin converting enzyme inhibitors, 62.4% to 72.4%; beta blockers, 76.3% to 82.6%; statins, 69.6% to 83.8%; and aspirin, 89.3% to 90.2%. CONCLUSION: The provision of contemporary online performance analyses has underpinned substantial improvement in the care of patients with acute coronary syndromes.

Two episodes of life-threatening anaphylaxis in the same patient to a chlorhexidine-sulphadiazine-coated central venous catheter.

Chlorhexidine allergy has been described in the literature, mainly in Japanese individuals. Most reactions have been limited to the skin, mild in severity and a result of chlorhexidine containing solutions such as 'Savlon' (Novartis Consumer Health, Horesham, UK). We describe what we believe is the first reported case of anaphylaxis in a European patient to a chlorhexidine- sulphadiazine-coated central venous catheter.

The World Survey of Cardiac Pacing and Implantable Cardioverter Defibrillators: calendar year 1997--Europe.

The registry of the European Working Group on Cardiac Pacing (EWGCP) is based on the European Pacemaker Identification Card originally designed in July 1978. National registration centers collect the local data and send aggregated annual data to the EWGCP. For 1997, data were obtained from 2,887 hospitals in 20 European countries representing a population of 568 million. Across all participating countries, the median value for all implanted pacemakers was 378 per million population. For initial pacemaker implants, the median value was 290 per million population. Single chamber atrial pacing was important in Denmark, the Netherlands, Poland, Slovak Republic, Spain, and Sweden for the treatment of sick sinus syndrome. Dual chamber pacing accounted for < 50% of initial implants in only 5 of 14 countries for atrioventricular block, and in only 3 of 15 countries for sick sinus syndrome. In 7 of 15 countries, unipolar ventricular leads were used in > or = 50% of cases. In 6 of 14 countries, there was > 15% use of unipolar atrial leads. Nine of 13 countries frequently used atrial active-fixation leads. For the 1997 survey, ICD data were obtained from 16 countries. The total number of ICDs per million population was a median value of 14. Initial ICD implants per million population was 11. Only 3 of 16 countries implanted a total of 30 or more ICDs per million population. Pacing and ICD practices were dependent on the availability of medical and technical resources and influenced by economic constraints inherent in health care administration and insurance coverage patterns.

Children followed with difficulty: how do they differ?

OBJECTIVE: To determine if very low birthweight children followed with ease differ in any perinatal or sociodemographic characteristics, or outcomes, compared with children followed with more difficulty. METHODOLOGY: Consecutive children of birthweight < 1000 g or with gestational ages < 28 weeks born in 1991 (n = 51) or of birthweight < 1500 g born in 1992 (n = 166) at the Royal Women's Hospital, Melbourne, surviving to 5 years of age, were assessed at 5 years of age, corrected for prematurity. Those who attended on the first mutually agreed appointment without substantial reluctance were considered to have been followed with ease. The remainder were considered to have been followed with difficulty. Outcomes included impairments such as cerebral palsy, blindness, deafness, and low IQ. Children had a disability if they had any of cerebral palsy, blindness, deafness requiring amplification, or an IQ more than 1 SD below the mean. RESULTS: Of the 217 survivors, 204 (94%) were assessed fully at 5 years of age. Of the 204 children assessed, 153 (75%) were followed with ease, and 51 (25%) with difficulty. Of data available in the perinatal period, significantly fewer children followed with more difficulty came from intact families, and more of their mothers had fewer than 12 years of schooling. More children followed with difficulty had a disability (41% compared with 19%), as they predominantly had lower IQ scores (mean difference in IQ - 12.7, 95% confidence interval - 18.0, - 7.4). The association between difficulty of assessment and both higher rates of disability and lower IQ scores remained after adjustment for significant perinatal and sociodemographic variables. CONCLUSIONS: Children followed with difficulty can partly be recognized on several sociodemographic characteristics in the perinatal period, and have substantially worse sensorineural outcomes than those followed with ease. In any longitudinal study, the more incomplete the follow up, the lower will be the rate of adverse sensorineural outcome.

Difference in the mortality of the CABRI diabetic and nondiabetic populations and its relation to coronary artery disease and the revascularization mode.

In diabetics with coronary artery disease (CAD), there remains uncertainty as to whether revascularization by percutaneous transluminal coronary angioplasty (PTCA) or coronary artery bypass surgery (CABG) is preferable. To address this, 4-year mortality and level of pre- and postrevascularization angiographic CAD (measured by a series of coronary scores) were compared between both diabetics and nondiabetics and between revascularization modes in the Coronary Angioplasty versus Bypass Revascularization Investigation population as a whole, and then substratified by diabetic status and then by procedure to which they were randomized. The 1,054 randomized subjects contained 125 diabetics (11.9%) who had significantly greater mortality than nondiabetics (RR 2.19, p = 0.001). Among diabetics or nondiabetics, there was no significant mortality difference between those randomized to PTCA versus those to CABG. Diabetics randomized to PTCA and those to CABG had higher mortalities than respective nondiabetics; the association reached significance only in the former (RR 2.41, p = 0.002). All subgroups had similar prerevascularization CAD. Postrevascularization residual CAD was consistently significantly greater in PTCA than in respective CABG subgroups. Most measurements of CAD were greater in diabetic than in nondiabetic subgroups, but none was significant. In the Coronary Angioplasty versus Bypass Revascularization Investigation, diabetics had double the mortality of nondiabetics; this difference was statistically significant both for the entire population and for those randomized to PTCA, but not for those randomized to CABG. Among diabetics or nondiabetics, there was no significant mortality difference between PTCA and CABG. The higher diabetic mortality was more likely related to more rapid disease progression than to greater postrevascularization disease.

Auditory function at 14 years of age of very-low-birthweight.

The aim of the study was to determine audiological function at 14 years of age of very-low-birthweight (VLBW < or = 1500 g) children compared with a cohort of normal birthweight (NBW > 2499 g) children. Participants were consecutive surviving preterm children of birthweight < 1000 g born between 1977 and 1982 (n=86) and of birthweight 1000 to 1500 g born between 1980 and 1982 (n=124) and randomly selected NBW children born between 1981 and 1982 (n=60). Audiometric tests included pure tone audiometry, tympanometry, stapedius muscle reflexes, and measures of central auditory processing. Psychometric tests included measures of IQ, academic achievement, and behaviour. There were no significant differences in rates of hearing impairment, abnormal tympanograms, figure-ground problems, or digit recall between VLBW children and NBW control children. VLBW children had higher rates of some central auditory processing problems, which in turn were associated with poorer intellectual, academic, and behavioural progress.

Cognition, academic progress, behavior and self-concept at 14 years of very low birth weight children.

The aim of this study was to compare cognition, academic progress, behavior, and self-concept children of very low birth weight (VLBW, birth weight < 1501 g) born in the period 1980 to 1982 with randomly selected children of normal birth weight (NBW, birth weight > 2,499 g). At 14 years of age, 130 (84.4%) of 154 VLBW and 42 (70.0%) of 60 NBW children were assessed. Ten VLBW children and one NBW child who had cerebral palsy were excluded. VLBW children scored at a significantly lower level on all three composite scales of the Wechsler Intelligence Scale for Children, 3rd Edition. VLBW children were also significantly disadvantaged on more specific cognitive processes, including tests of visual processing and visual memory and on subtests reflecting learning and problem solving. Only in arithmetic was a difference between the groups discerned on tests of achievement. Significantly more VLBW children were rated by teachers as socially rejected and by their parents as having learning problems at school. VLBW children had significantly reduced self-esteem. VLBW children had more cognitive, academic, and behavioral problems and lower self-esteem at 14 years of age than NBW control subjects.

The effect of adjusting for baseline risk factors and post revascularisation coronary disease on comparisons between coronary angioplasty and bypass surgery.

BACKGROUND: In CABRI at 1 year PTCA was associated with greater repeat revascularisation and angina (but not myocardial infarction or death). We determined whether adjusting for baseline risk factors and post revascularisation coronary disease offsets this disadvantage of PTCA. METHODS: In the CABRI population the crude association of revascularisation mode (i.e. PTCA or CABG) with four clinical outcome (i.e. mortality, myocardial infarction, repeat revascularisation and angina) was adjusted for the baseline risk factors using a logistic regression model for each clinical outcome. A number of measures of angiographic coronary disease were used to assess post revascularisation coronary disease. One at a time, each of these measures was added to each of the four outcome models, to adjust for post revascularisation coronary disease. RESULTS: Comparing adjusted and crude unadjusted association of PTCA with repeat revascularisation there was an increase from 12.8 (P<0.0005) (crude relative risk) to 16.7 (P<0.0005) (adjusted odds ratio), with angina, from 1.89 (P=0.001) to 1.98 (P<0.0019), and with mortality from 1.84 (P=0.092) to 2.15 (P=0.060). PTCA was not significantly associated with myocardial infarction, either crudely or after adjustment. CONCLUSION: Adjusting for baseline risk factors and post revascularisation coronary disease tended to strengthen rather than weaken associations between PTCA and 1 year mortality, repeat revascularisation and angina at 1 year.

Newborn screening for congenital hypothyroidism, Victoria, Australia, 1977-1997. Part 1: The screening programme, demography, baseline perinatal data and diagnostic classification.

Clinical, demographic and laboratory data from infants with congenital hypothyroidism (CH) born in the Australian state of Victoria from the commencement of neonatal screening in mid-1977 until December 1988 are reported. These provide a baseline for a 12-year prospective longitudinal study on physical and neuro-psychological outcome until mid-1997, the subject of a second paper. Infants with CH were detected using a primary TT4 screening test. Demographic data were collected prospectively using a clinical assessment protocol. Nearly all affected infants underwent 99mTc pertechnetate scanning at the initial assessment to determine the underlying aetiology of their hypothyroidism. 704,723 infants were screened and 199 with permanent primary hypothyroidism (one in 3,541) were identified. The most common aetiologies were thyroid ectopia (46%), thyroid aplasia (33%), and 'dyshormonogenesis' (11%). The clinical abnormalities classically described in CH were more evident in infants with aplasia, and the striking female preponderance in infants with thyroid dysplasia (syn. dysgenesis) was confirmed. Other features included increased frequencies of 'dyshormonogenesis' in infants of parents of Middle-Eastern origin and of labour induction in infants with dysplasia. A closed posterior fontanelle was not found in any infant with thyroid aplasia.

Newborn screening for congenital hypothyroidism, Victoria, Australia, 1977-1997. Part 2: Treatment, progress and outcome.

A controlled longitudinal prospective study is reported of physical and neuropsychological progress up to 12 years in 152 children with congenital hypothyroidism (CH), detected by newborn screening in the Australian state of Victoria and born between the onset of screening in mid-1977 and December 1988. Linear growth of the CH children was normal. Throughout they were slightly heavier and the median head circumference was slightly larger compared with reference data. Those with thyroid aplasia required a marginally larger dose of thyroxine to achieve euthyroidism. Assessment of cognitive outcome in the children with permanent primary CH revealed the mean scores at 2, 5 and 8 years to be from 8.5 (p<0.001) to 10.2 (p<0.001) points lower than in a group of 60 euthyroid controls. However, there was large overlap and, of the affected children, only 10.1% at 2 years, 3.9% at 5 years and 6.8% at 8 years fell more than 2 SD below the means of the euthyroid controls. On univariate analysis, variables shown to have significant correlation with cognitive outcome at 8 years in the CH children were newborn activity, baseline TT4 and FTI, initial T4 dosage, socio-economic classification, maternal age, maternal education and presence of a serious accompanying disorder. On multiple regression analysis, significant variables were baseline bone age, maternal age and education, and presence of a serious accompanying disorder. No single thyroidal or extra-thyroidal variable could be identified to account for the discrepancy between the children with CH and the controls.

Relation between coronary artery disease, baseline clinical variables, revascularization mode, and mortality. CABRI Participants. Coronary Angioplasty vs. Bypass Revascularisation Investigation.

The Coronary Angioplasty vs. Bypass Revascularisation Investigation (CABRI) trial comparing percutaneous transluminal coronary angioplasty (PTCA) with coronary artery bypass grafting did not show a difference in mortality with either procedure. Nonrandomized studies suggest that coronary artery disease (CAD) severity and distribution influences outcome. In the present study we explored the effect of prerevascularization CAD on 1-year mortality in the CABRI population, while adjusting for other baseline variables. Of the 1,054 patients recruited, there were sufficient angiographic results to derive the CAD scores in 974 (92.4%). Of these 974, there were 32 deaths. A number of CAD scores, both weighted for proximal disease (Duke and Leaman) and nonweighted, were used. These scores were then cross-tabulated against mortality. Demographic and clinical variables were also cross-tabulated against mortality and used to derive an initial logistic regression model to predict mortality. The effect of adding each of the CAD scores to this initial model was then assessed. After inclusion of the CAD scores, the best model was: (1) presence of peripheral vascular disease (odds ratio [OR] 3.89, p = 0.0025), (2) previous cerebrovascular accident (OR 2.86, p = 0.043), (3) older age (OR 1.05, p = 0.039), (4) a higher Duke score (OR 2.84, p = 0.0061), and (5) having undergone PTCA (OR 2.12, p = 0.047). In the CABRI population, adjustment for baseline variables, including prerevascularization CAD, revealed significantly higher mortality in those who underwent PTCA than in those who underwent coronary artery bypass grafting.

Antenatal corticosteroids and outcome at 14 years of age in children with birth weight less than 1501 grams.

OBJECTIVE: To determine whether exposure to antenatal corticosteroid therapy was associated with adverse effects on growth, sensorineural outcome, or lung function of children of birth weight <1501 g at 14 years of age. DESIGN: Cohort study. SETTING: The Royal Women's Hospital, Melbourne, Australia. SUBJECTS: One hundred fifty-four consecutive survivors born from October 1, 1980 to March 31, 1982. INTERVENTIONS: The mothers of 78 survivors (51%) had been given corticosteroids antenatally to accelerate fetal lung maturation. Treatment with antenatal corticosteroids was nonrandom. No mother received >1 course of corticosteroids. OUTCOME MEASURES: The children were assessed at 14 years of age, corrected for prematurity. All assessors were unaware of the exposure of the child to antenatal corticosteroids. The assessments included measurements of growth and neurological, cognitive, and lung function. Growth measurements were converted into z scores (standard deviation) for the appropriate age and gender. RESULTS: Of the 154 survivors, 130 (84%) were assessed at 14 years of age. Overall, the children exposed to antenatal corticosteroids were significantly taller (height z score; mean difference:.39; 95% confidence interval:.001-. 79) and had better cognitive functioning (Wechsler Intelligence Scale for Children-Third Edition Full Scale; IQ mean difference: 6. 2; 95% confidence interval:.8-11.6) than those not exposed to corticosteroids. There were no other differences in sensorineural outcomes between the groups. Lung function was not significantly different between the groups. No conclusions were altered by adjustment for confounding variables. CONCLUSIONS: Exposure to 1 course of antenatal corticosteroid therapy was associated with some clinically and statistically improved outcomes at 14 years of age in children of birth weight <1501 g, with no obvious adverse effects on growth or on sensorineural, cognitive, or lung function. corticosteroids, growth, cognitive, IQ, lung function, adolescence.

Methylxanthines and sensorineural outcome at 14 years in children < 1501 g birthweight.

OBJECTIVES: Methylxanthines, including theophylline, have been used extensively and successfully to treat apnoea in preterm infants. However, long-term consequences of such therapy are largely unknown. The aim of this study was to determine the relationship between theophylline therapy and outcome at 14 years of age in surviving preterm children of birthweight < 1501 g. METHODOLOGY: The subjects of this study were 154 consecutive survivors with birthweights < 1501 g born from 1 October 1980 to 31 March 1982; 130 (84.4%) were assessed at 14 years of age. Outcomes included motor function, psychological test scores, and growth. RESULTS: Of the 130 children assessed, 69 (53.1%) had been exposed to theophylline; 13.0% had cerebral palsy, significantly higher than 1.6% in the 61 children not exposed to theophylline (P < 0.02). This difference remained statistically significant after adjusting for potential confounding variables including the presence of cerebroventricular haemorrhage. In contrast, after adjusting for known confounding variables, children who had received theophylline achieved higher psychological test scores. There was no association between theophylline therapy and growth. CONCLUSIONS: Theophylline therapy in the newborn period is associated with some evidence of harmful, but also helpful sensorineural effects at 14 years of age.