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1.
Phys Rev Lett ; 132(2): 024001, 2024 Jan 12.
Article in English | MEDLINE | ID: mdl-38277580

ABSTRACT

The classical Richtmyer-Meshkov instability (RMI) is a hydrodynamic instability characterizing the evolution of an interface following shock loading. In contrast to other hydrodynamic instabilities such as Rayleigh-Taylor, it is known for being unconditionally unstable: regardless of the direction of shock passage, any deviations from a flat interface will be amplified. In this article, we show that for negative Atwood numbers, there exist special sequences of shocks which result in a nearly perfectly suppressed instability growth. We demonstrate this principle computationally and experimentally with stepped fliers and phase transition materials. A fascinating immediate corollary is that in specific instances, a phase-transitioning material may self-suppress RMI.

2.
Pediatr Cardiol ; 44(3): 540-548, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36422652

ABSTRACT

Over the past 2 decades, fundamentals of exercise medicine, including clinical exercise testing, assessment and promotion of physical activity, exercise prescription, and supervised exercise training/rehabilitation programming have demonstrated considerable clinical value in the management of children and adolescents with congenital and acquired heart disease. Although the principles of exercise medicine have become an integral component in pediatric cardiology, there are no standardized training recommendations for exercise physiology during pediatric cardiology fellowship at this time. Thus, the Pediatric Cardiology Exercise Medicine Curriculum Committee (PCEMCC) was formed to establish core and advanced exercise physiology training recommendations for pediatric cardiology trainees. The PCEMCC includes a diverse group of pediatric cardiologists, exercise physiologists, and fellowship program directors. The expert consensus training recommendations are by no means a mandate and are summarized herein, including suggestions for achieving the minimum knowledge and training needed for general pediatric cardiology practice.


Subject(s)
Cardiology , Heart Diseases , Child , Humans , Adolescent , Fellowships and Scholarships , Cardiology/education , Curriculum , Exercise
3.
J Intellect Disabil Res ; 66(6): 503-516, 2022 06.
Article in English | MEDLINE | ID: mdl-35191124

ABSTRACT

BACKGROUND: Although correlates of physical activity (PA) have been extensively examined in both children and adolescents who are typically developing, little is known about correlates of moderate to vigorous physical activity (MVPA) and sedentary time in adolescents with intellectual and developmental disabilities (IDD). Therefore, we examined intrapersonal, interpersonal and environmental factors and their association with device-based MVPA and sedentary time in adolescents with IDD. METHODS: MVPA and sedentary time was assessed using a hip-worn ActiGraph model wGT3x-BT tri-axial accelerometer across a 7-day period in adolescents with IDD and one of their parents. Pearson and point-biserial correlations were calculated to inspect the associations of PA (MVPA, sedentary time) with intrapersonal factors (demographic characteristic, BMI, waist circumference, motor ability, muscle strength, grip strength, cardiovascular fitness and self-efficacy for PA), interpersonal factors (parent demographics, parent BMI, parent MVPA and sedentary time, family social support for PA, parent barriers and support for PA, parent's beliefs/attitudes towards PA and number of siblings), and environmental factors (meteorologic season and COVID-19). Ordinary least squares regression was used to estimate the unique contributions of key factors to PA after controlling for participants' age, sex, race, waist circumference and total wear time. RESULTS: Ninety-two adolescents (15.5 ± 3.0 years old, 21.7% non-White, 6.5% Hispanic, 56.5% female) provided valid accelerometer data. Average sedentary time was 494.6 ± 136.4 min/day and average MVPA was 19.8 ± 24.2 min/day. Age (r = 0.27, P = 0.01), diagnosis of congenital heart disease (r = -0.26, P = 0.01) and parent sedentary time (r = 0.30, P = 0.01) were correlated with sedentary time. BMI (r = -0.24, P = 0.03), waist circumference (r = -0.28, P = 0.01), identifying as White (r = -0.23, P = 0.03) and parent MVPA (r = 0.56, P < 0.001) were correlated with MVPA. After adjusting for the adolescent's age, sex, race, waist circumference, and total wear time, the association between parent and adolescent MVPA remained significant (b = 0.55, P < 0.01, partial η2  = 0.11). CONCLUSION: The results of this study provide evidence that race, waist circumference and parental MVPA may influence the amount of MVPA in adolescents with IDD. The limited available information and the potential health benefits of increased MVPA highlight the need to evaluate the effectiveness of multi-component interventions targeting both intrapersonal and interpersonal levels to promote increased PA in adolescents with IDD.


Subject(s)
COVID-19 , Sedentary Behavior , Adolescent , Child , Developmental Disabilities , Exercise/physiology , Female , Humans , Male , Waist Circumference
4.
J Intellect Disabil Res ; 66(6): 545-557, 2022 06.
Article in English | MEDLINE | ID: mdl-34915594

ABSTRACT

BACKGROUND: Adolescents and young adults with intellectual and developmental disabilities (IDD) have high rates of obesity and low levels of physical activity. This analysis examined changes in light, moderate-to-vigorous physical activity (MVPA) and sedentary time, and the association between changes in MVPA and weight loss in adolescents and young adults with IDD and overweight and obesity participating in a 6-month multi-component weight loss intervention. METHODS: Adolescents and young adults with IDD and overweight or obesity (body mass index ≥ 85 percentile, n = 110, age ~16 years, 52.7% female) and a parent were randomised to one of three intervention groups: face-to-face delivery/conventional reduced energy diet (n = 36), remote delivery (RD)/conventional reduced energy diet (n = 39), or RD/reduced energy enhanced stop light diet (eSLD) (n = 35.) Participants were asked to engage in 60 min/day of MVPA on 5 or more days/wk. Participants and a parent attended twice monthly education/behavioural counselling sessions with a health educator to assist participants in complying with dietary and MVPA recommendations. Education/counselling in the RD arms was delivered remotely using video conferencing, and self-monitoring of MVPA and daily steps was completed using a wireless activity tracker. Education/counselling in the face-to-face arm was delivered during home-visits and self-monitoring of MVPA and daily steps was completed by self-report using paper tracking forms designed for individuals with IDD. MVPA, light activity, and sedentary time were assessed over 7 days at baseline and 6 months using a portable accelerometer (ActiGraph wGT3x-BT). RESULTS: Mixed modelling analysis completed using participants with valid accelerometer data (i.e. ≥4-10 h days) at baseline (n = 68) and 6 months (n = 30) revealed no significant changes in light, moderate- MVPA, or sedentary time across the 6-month intervention (all P > 0.05). Participants obtained 15.2 ± 21.5 min/day of MVPA at baseline and 19.7 ± 19.7 min/day at 6 months (P = 0.119). Mixed modelling indicated no significant effects of group (P = 0.79), time (P = 0.10), or group-by-time interaction (P = 0.21) on changes in MVPA from baseline to 6 months. Correlational analysis conducted on participants with valid accelerometer data at both baseline and 6 months (n = 24) revealed no significant associations between baseline sedentary time (r = 0.10, P = 0.40) and baseline MVPA (r = -0.22, P = 0.30) and change in MVPA across the 6-month intervention. Additionally, attendance at education/counselling sessions (r = 0.26, P = 0.22) and frequency of self-monitoring of MVPA were not significantly associated with change in MVPA from baseline to 6 months (r = 0.26, P = 0.44). Baseline MVPA (r = 0.02, P = 0.92) and change in MVPA from baseline to 6 months (r = 0.13, P = 0.30) were not associated with changes in body weight across the 6-month intervention. CONCLUSION: We observed a non-significant increase in MVPA (30%), which was not associated with the magnitude of weight loss in a sample of adolescents and young adults with IDD who participated in a 6-month multi-component weight loss intervention. Additional strategies to increase MVPA in adolescents and young adults with IDD participating in weight loss interventions need to be developed and evaluated.


Subject(s)
Overweight , Weight Reduction Programs , Adolescent , Child , Developmental Disabilities/complications , Exercise , Female , Humans , Male , Obesity/complications , Overweight/therapy , Weight Loss , Young Adult
5.
J Intellect Disabil Res ; 64(3): 221-233, 2020 03.
Article in English | MEDLINE | ID: mdl-31944472

ABSTRACT

BACKGROUND: Down syndrome (DS) is one of the most common birth defects in the USA associated with high levels of overweight and obesity. Unique characteristics of adults with DS that may contribute to the high levels of obesity are high rates of hypothyroidism, poor muscle tone, altered gait and lower resting metabolic rate. Due to these factors, it is unknown if the same weight management interventions that are effective in adults with intellectual or developmental disability (IDD) without DS are as effective in those with DS. Therefore, the purpose of this secondary analysis was to compare changes in weight, diet and physical activity between participants with DS-related and non-DS-related IDD participating in an 18-month weight management trial. METHODS: We used propensity score methods to adjust baseline variables of overweight/obese adults with and without DS participating in an 18-month effectiveness trial with 6 months weight loss and 12 months weight maintenance. Participants followed one of two reduced calorie diet plans, obtained 150 min of moderate-vigorous intensity physical activity (MVPA) per week, and logged dietary intake daily. A health educator held monthly at-home visits with participants and a caregiver to give feedback on intervention compliance. RESULTS: Out of the 124 participants that met the criteria for inclusion, 21 were diagnosed with DS and 103 with non-DS-related IDD. Twenty out of 21 participants with DS were successfully matched. Clinically significant weight loss was seen at 18 months in participants with DS (-5.2%) and non-DS-related IDD (-6.8%), with no difference between groups (P = 0.53). Significant reductions in energy intake were seen across the 18-month intervention in both DS and non-DS-related IDD groups with between-group differences at 12 months only (1119 vs. 1492 kcal/day, respectively; P = 0.003). Although MVPA did not increase in either group across the intervention, those with non-DS-related IDD had higher levels of MVPA compared with those with DS across 18 months. CONCLUSION: Participants with DS lost a clinically significant amount of weight across the 18-month intervention. Compared with those with non-DS-related IDD, those with DS lost similar amounts of weight, had similar decreases in energy intake and participated in less MVPA across the 18-month intervention. Although individuals with DS have physiological factors that may contribute to obesity, weight management interventions designed for individuals with IDD may be equally effective in this population.


Subject(s)
Body Weight Maintenance , Developmental Disabilities/rehabilitation , Down Syndrome/rehabilitation , Outcome Assessment, Health Care , Overweight/therapy , Weight Reduction Programs , Adult , Comorbidity , Developmental Disabilities/epidemiology , Diet Therapy , Down Syndrome/epidemiology , Exercise Therapy , Female , Humans , Male , Obesity/diet therapy , Obesity/epidemiology , Obesity/rehabilitation , Overweight/diet therapy , Overweight/epidemiology , Overweight/rehabilitation , Patient Education as Topic , Propensity Score
6.
Forensic Sci Int ; 289: 320-328, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29933204

ABSTRACT

Unmarked graves are difficult to locate once the ground surface no longer shows visible evidence of disturbance, posing significant challenges to missing person investigations. This research evaluates the use of terrestrial LIDAR point data for measuring localized elevation change at human grave surfaces. Three differently sized human graves, one control-pit, and surrounding undisturbed ground, were scanned four times between February 2013 and November 2014 using a tripod-mounted terrestrial laser scanner. All the disturbed surfaces exhibited measurable and localized elevation change, allowing for separation of disturbed and undisturbed ground. This study is the first to quantify elevation changes to human graves over time and demonstrates that terrestrial LIDAR may contribute to multi-modal data collection approach to improve unmarked grave detection.


Subject(s)
Burial , Lasers , Remote Sensing Technology , Soil , Cadaver , Forensic Sciences/methods , Humans
7.
Ann R Coll Surg Engl ; 99(5): 373-377, 2017 May.
Article in English | MEDLINE | ID: mdl-28462648

ABSTRACT

Introduction The aim of this study was to identify patient factors including serum biomarkers that may predict response to neoadjuvant chemoradiotherapy (CRT) in patients with locally advanced rectal cancer staged on magnetic resonance imaging. Prediction of response may be helpful when selecting patients for a non-operative programme. Methods A retrospective review was carried out of patients undergoing neoadjuvant CRT for rectal cancer, conducted at the Royal Devon and Exeter Hospital. All patients were managed through the multidisciplinary team. Receiver operating characteristic (ROC) curve analysis was undertaken to assess the ability of biomarkers to predict response to neoadjuvant CRT. The biomarkers assessed included neutrophils, lymphocytes, monocytes, haemoglobin, platelets, C-reactive protein and carcinoembryonic antigen. Results Seventy-three patients underwent neoadjuvant CRT between January 2006 and December 2011. Nine (12.3%) of these experienced a clinical complete response and were managed with a 'watch and wait' approach. An additional ten patients (13.7%) had a pathological complete response following surgery. Using ROC curve analysis, the biomarkers with the largest area under the curve (AUC) were pre-CRT haemoglobin and post-CRT lymphocyte concentrations, producing AUC values of 0.673 and 0.618 respectively for clinical complete response. Pre-CRT haemoglobin and neutrophil concentrations produced the highest AUC values for pathological complete response at 0.591 and 0.614 respectively. Conclusions None of the assessed biomarkers offer the ability to predict response to neoadjuvant CRT in patients with rectal cancer. They cannot therefore assist in identifying complete clinical or pathological responders who could be considered for a non-operative, observational approach.


Subject(s)
Biomarkers, Tumor/blood , Chemoradiotherapy , Neoadjuvant Therapy , Rectal Neoplasms/blood , Rectal Neoplasms/therapy , Aged , Female , Humans , Male , Middle Aged , Neoplasm Recurrence, Local , Predictive Value of Tests , Retrospective Studies , Treatment Outcome
8.
Br Dent J ; 221(8): 509-514, 2016 Oct 21.
Article in English | MEDLINE | ID: mdl-27767153

ABSTRACT

Background The 2013 Children's Dental Health survey is the fifth in a series of national surveys.Aims This paper describes children's reported use of dental services, their experience of receiving dental treatment and parental satisfaction with services.Methodology A representative sample of children (aged 5, 8, 12 and 15 years) in England, Wales and Northern Ireland were invited to participate in dental examinations. Older children and all parents were invited to complete a questionnaire about oral health behaviours and attitudes.Results Over 80% of 12- and 15-year-olds reported attending for a check-up. According to parents, 9 in 10 children of all ages had visited a dentist in the last year and 9 in 10 parents reported they were satisfied with the last dental practice their child had visited. There was some variation by country with respect to children's experiences of fillings and extractions.Conclusions There has been little change in the reported attendance patterns of children since the 2003 survey. Family deprivation (measured by children's eligibility for free school meals) negatively influenced dental attendance for regular check-ups, attendance within the last 12 months and the likelihood of having experienced difficulties accessing NHS dental services for children.


Subject(s)
Dental Health Services/statistics & numerical data , Dental Health Surveys , Oral Health , Adolescent , Child , England , Female , Humans , Male , Northern Ireland , Wales
9.
S Afr Med J ; 106(4): 25-6, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27303779

ABSTRACT

Bronchiolitis may be diagnosed on the basis of clinical signs and symptoms. In a young child, the diagnosis can be made on the clinical pattern of wheezing and hyperinflation. Clinical symptoms and signs typically start with an upper respiratory prodrome, including rhinorrhoea, low-grade fever, cough and poor feeding, followed 1 - 2 days later by tachypnoea, hyperinflation and wheeze as a consequence of airway inflammation and air trapping.The illness is generally self limiting, but may become more severe and include signs such as grunting, nasal flaring, subcostal chest wall retractions and hypoxaemia. The most reliable clinical feature of bronchiolitis is hyperinflation of the chest, evident by loss of cardiacdullness on percussion, an upper border of the liver pushed down to below the 6th intercostal space, and the presence of a Hoover sign(subcostal recession, which occurs when a flattened diaphragm pulls laterally against the lower chest wall).Measurement of peripheral arterial oxygen saturation is useful to indicate the need for supplemental oxygen. A saturation of <92% at sea level and 90% inland indicates that the child has to be admitted to hospital for supplemental oxygen. Chest radiographs are generally unhelpful and not required in children with a clear clinical diagnosis of bronchiolitis.Blood tests are not needed routinely. Complete blood count tests have not been shown to be useful in diagnosing bronchiolitis or guiding its therapy. Routine measurement of C-reactive protein does not aid in management and nasopharyngeal aspirates are not usually done.Viral testing adds little to routine management. Risk factors in patients with severe bronchiolitis that require hospitalisation and may even cause death, include prematurity, congenital heart disease and congenital lung malformations.


Subject(s)
Bronchiolitis, Viral/diagnosis , Acute Disease , Blood Cell Count , Diagnosis, Differential , Humans , Nasopharynx/virology , Radiography, Thoracic , Risk Factors , South Africa
10.
S Afr Med J ; 106(4): 27-9, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27303780

ABSTRACT

Management of acute viral bronchiolitis is largely supportive. There is currently no proven effective therapy other than oxygen for hypoxic children. The evidence indicates that there is no routine benefit from inhaled, rapid short-acting bronchodilators, adrenaline or ipratropium bromide for children with acute viral bronchiolitis. Likewise, there is no demonstrated benefit from routine use of inhaled or oral corticosteroids, inhaled hypertonic saline nebulisation, montelukast or antibiotics. The last should be reserved for children with severe disease, when bacterial co-infection is suspected. Prevention of respiratory syncytial virus (RSV) disease remains a challenge. A specific RSV monoclonal antibody, palivizumab, administered as an intramuscular injection, is available for children at risk of severe bronchiolitis, including premature infants, young children with chronic lung disease, immunodeficiency, or haemodynamically significant congenital heart disease. Prophylaxis should be commenced at the start of the RSV season and given monthly during the season. The development of an RSV vaccine may offer a more effective alternative to prevent disease, for which the results of clinical trials are awaited. Education of parents or caregivers and healthcare workers about diagnostic and management strategies should include the following: bronchiolitis is caused by a virus; it is seasonal; it may start as an upper respiratory tract infection with low-grade fever; symptoms are cough and wheeze, often with fast breathing; antibiotics are generally not needed; and the condition is usually self limiting, although symptoms may occur for up to four weeks in some children.


Subject(s)
Bronchiolitis, Viral/prevention & control , Bronchiolitis, Viral/therapy , Acute Disease , Antiviral Agents/therapeutic use , Caregivers/education , Child , Humans , Infant , Infant, Newborn , Infant, Premature , Palivizumab/therapeutic use , Parents/education , Patient Education as Topic , Respiratory Syncytial Virus Infections/prevention & control , Risk Factors , South Africa , Viral Vaccines
11.
Int Rev Neurobiol ; 126: 1-14, 2016.
Article in English | MEDLINE | ID: mdl-27055609

ABSTRACT

The societal burden created by alcohol and drug use disorders is estimated to be on the order of hundreds of billions of dollars, creating a need for effective medications to reduce use and prevent relapse. While there are FDA-approved medications to facilitate abstinence and prevent relapse for some indications including, alcohol, tobacco, and opiate use disorders, there are no approved treatments for other abused substances, including cocaine, methamphetamine, and cannabis, leaving these critical medical needs unmet. The development of such medications has fallen largely to the government with efforts spearheaded by the National Institute on Drug Abuse and the National Institute on Alcoholism and Alcohol Abuse. Both agencies have medication development programs with preclinical components that include the standardized evaluation of compounds using animal models. This chapter describes the rationale and considerations involved in the use of such models, including reinstatement of drug self-administration.


Subject(s)
Drug Discovery , Drug Evaluation , Substance-Related Disorders/drug therapy , Animals , Humans , Predictive Value of Tests , Reproducibility of Results
12.
Diabet Med ; 33(2): 243-51, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26248590

ABSTRACT

AIMS: To explore health professionals' views about insulin pump therapy [continuous subcutaneous insulin infusion (CSII)] and the types of individuals they thought would gain greatest clinical benefit from using this treatment. METHODS: In-depth interviews with staff (n = 18) who delivered the Relative Effectiveness of Pumps Over MDI and Structured Education (REPOSE) trial. Data were analysed thematically. RESULTS: Staff perceived insulin pumps as offering a better self-management tool to some individuals due to the drip feed of insulin, the ability to alter basal rates and other advanced features. However, staff also noted that, because of the diversity of features on offer, CSII is a more technically complex therapy to execute than multiple daily injections. For this reason, staff described how, alongside clinical criteria, they had tended to select individuals for CSII in routine clinical practice based on their perceptions about whether they possessed the personal and psychological attributes needed to make optimal use of pump technology. Staff also described how their assumptions about personal and psychological suitability had been challenged by working on the REPOSE trial and observing individuals make effective use of CSII who they would not have recommended for this type of therapy in routine clinical practice. CONCLUSIONS: Our findings add to those studies that highlight the difficulties of using patient characteristics and variables to predict clinical success using CSII. To promote equitable access to CSII, attitudinal barriers and prejudicial assumptions amongst staff about who is able to make effective use of CSII may need to be addressed.


Subject(s)
Attitude of Health Personnel , Diabetes Mellitus, Type 1/drug therapy , Hyperglycemia/prevention & control , Hypoglycemia/prevention & control , Insulin Infusion Systems , Patient Education as Topic , Precision Medicine , Adaptation, Psychological , Adult , Clinical Decision-Making , Cluster Analysis , Combined Modality Therapy/adverse effects , Combined Modality Therapy/nursing , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/diet therapy , Diabetes Mellitus, Type 1/nursing , Follow-Up Studies , Humans , Hypoglycemia/chemically induced , Hypoglycemia/epidemiology , Insulin Infusion Systems/adverse effects , Nurse Clinicians , Nutritionists , Patient Compliance , Precision Medicine/nursing , Prejudice/prevention & control , Professional-Patient Relations , Qualitative Research , Risk , United Kingdom/epidemiology , Workforce
13.
Colorectal Dis ; 18(2): 135-46, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26559167

ABSTRACT

AIM: There is ambiguity with regard to the optimal management of anal intraepithelial neoplasia (AIN) III. The aim of this review was to assess and compare international/national society guidelines currently available in the literature on the management, treatment and surveillance of AIN III. We also aimed to assess the quality of the studies used to compile the guidelines and to clarify the terminology used in histological assessment. METHOD: An electronic search of PubMed and Embase was performed using the search terms 'anal intraepithelial neoplasia', 'AIN', 'anal cancer', 'guidelines', 'surveillance' and 'management'. Literature reviews and guidelines or practice guidelines in peer reviewed journals from 1 January 2000 to 31 December 2014 assessing the treatment, surveillance or management of patients with AIN related to human papilloma virus were included. The guidelines identified by the search were assessed for the quality of evidence behind them using the Oxford Centre for Evidence-based Medicine 2011 Levels of Evidence. RESULTS: The database search identified 5159 articles and two further guidelines were sourced from official body guidelines. After inclusion criteria were applied, 28 full-text papers were reviewed. Twenty-five of these were excluded, leaving three guidelines for inclusion in the systematic review: those published by the Association of Coloproctology of Great Britain and Ireland, the American Society of Colon and Rectal Surgeons and the Italian Society of Colorectal Surgery. No guidelines were identified on the management of AIN III from human papilloma virus associations and societies. All three guidelines agree that a high index of clinical suspicion is essential for diagnosing AIN with a disease-specific history, physical examination, digital rectal examination and anal cytology. There is interchange of terminology from high-grade AIN (HGAIN) (which incorporates AIN II/III) and AIN III in the literature leading to confusion in therapy use. Treatment varies from immunomodulation and photodynamic therapy to targeted destruction of areas of HGAIN/AIN II/III using infrared coagulation, electrocautery, cryotherapy or surgical excision but with little consensus between the guidelines. Recommendations on surveillance strategies are similarly discordant, ranging from 6-monthly physical examination to annual anoscopy ± biopsy. Over 50% of the recommendations are based on Level 3 or Level 4 evidence and many were compiled using studies that were more than 10 years old. CONCLUSION: Despite concordance regarding diagnosis, there is significant variation in the guidelines over recommendations on the treatment and surveillance of patients with HGAIN/AIN II/III. All three sets of guidelines are based on low level, outdated evidence originating from the 1980s and 1990s.


Subject(s)
Anus Neoplasms/diagnosis , Anus Neoplasms/therapy , Carcinoma in Situ/diagnosis , Carcinoma in Situ/therapy , Population Surveillance/methods , Practice Guidelines as Topic , Terminology as Topic , Disease Management , Guideline Adherence , Humans
14.
Genome Announc ; 3(3)2015 May 07.
Article in English | MEDLINE | ID: mdl-25953162

ABSTRACT

Rhodococcus sp. strain PML026 produces an array of trehalolipid biosurfactant compounds in order to utilize hydrophobic carbon sources, such as oils and alkanes. Here, we report the high-quality draft genome sequence of this strain, which has a total length of 5,168,404 bp containing 4,835 protein-coding sequences, 12 rRNAs, and 45 tRNAs.

15.
Biotechnol Rep (Amst) ; 7: 87-94, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26753128

ABSTRACT

Microalgae have potential as a chemical feed stock in a range of industrial applications. Nannochloropsis salina was subject to EMS mutagenesis and the highest lipid containing cells selected using fluorescence-activated cell sorting. Assessment of growth, lipid content and fatty acid composition identified mutant strains displaying a range of altered traits including changes in the PUFA content and a total FAME increase of up to 156% that of the wild type strain. Combined with a reduction in growth this demonstrated a productivity increase of up to 76%. Following UV mutagenesis, lipid accumulation of the mutant cultures was elevated to more than 3 fold that of the wild type strain, however reduced growth rates resulted in a reduction in overall productivity. Changes observed are indicative of alterations to the regulation of the omega 6 Kennedy pathway. The importance of these variations in physiology for industrial applications such as biofuel production is discussed.

17.
Phys Rev Lett ; 112(9): 098101, 2014 Mar 07.
Article in English | MEDLINE | ID: mdl-24655282

ABSTRACT

We consider the spatial dependence of filamentous protein self-assembly. Through studying the cases where the spreading of aggregated material is dominated either by diffusion or by growth, we derive analytical results for the spatial evolution of filamentous protein aggregation, which we validate against Monte Carlo simulations. Moreover, we compare the predictions of our theory with experimental measurements of two systems for which we identify the propagation as either growth or diffusion controlled. Our results connect the macroscopic observables that characterize the spatial propagation of protein self-assembly with the underlying microscopic processes and provide physical limits on spatial propagation and prionlike behavior associated with protein aggregation.


Subject(s)
Models, Chemical , Proteins/chemistry , Diffusion , Monte Carlo Method , Polymerization , Proteins/metabolism , Stochastic Processes
18.
J Appl Microbiol ; 115(3): 744-55, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23789786

ABSTRACT

AIMS: The aim of this study was to evaluate biosurfactant production by a novel marine Rhodococcus sp., strain PML026 and characterize the chemical nature and properties of the biosurfactant. METHODS AND RESULTS: A novel marine bacterium (Rhodococcus species; strain PML026) was shown to produce biosurfactant in the presence of hydrophobic substrate (sunflower oil). Biosurfactant production (identified as a trehalolipid) was monitored in whole-batch cultures (oil layer and aqueous phase), aqueous phase (no oil layer) and filtered (0·2 µm) aqueous phase (no oil or cells; extracellular) and was shown to be closely associated with growth/biomass production. Extracellular trehalolipid levels increased postonset of stationary growth phase. Purified trehalolipid was able to reduce the surface tension of water to 29 mN m(-1) at Critical Micellar Concentration (CMC) of c. 250 mg l(-1) and produced emulsions that were stable to a wide range of conditions (pH 2-10, temperatures of 20-100°C and NaCl concentrations of 5-25% w/v). Separate chemical analyses of the intact trehalolipid and its constituents demonstrated the compound was in fact a mixture of homologues (>1180 MW) consisting of a trehalose moiety esterified to a series of straight chain and hydroxylated fatty acids. CONCLUSIONS: The trehalolipid biosurfactant produced by the novel marine strain Rhodococcus sp. PML026 was characterized and exhibited high surfactant activity under a wide range of conditions. SIGNIFICANCE AND IMPACT OF STUDY: Strain PML026 of Rhodococcus sp. is a potential candidate for bioremediation or biosurfactant production for various applications.


Subject(s)
Glycolipids/chemistry , Rhodococcus/metabolism , Surface-Active Agents/chemistry , Biodegradation, Environmental , Emulsions , Glycolipids/isolation & purification , Glycolipids/metabolism , Micelles , Rhodococcus/growth & development , Surface Tension , Surface-Active Agents/isolation & purification , Surface-Active Agents/metabolism , Temperature , Trehalose/analysis
19.
Br Dent J ; 214(2): 71-5, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23348457

ABSTRACT

This is the final paper in a series reporting on the results of the 2009 Adult Dental Health Survey. Since 1968 national adult surveys have been repeated every decade with broadly similar methods providing a unique overview of trends in oral health over a 40-year period. This paper aims to explore the implications for dentists and oral health policy of the key results from the Adult Dental Health Survey 2009. Although repeat, cross-sectional, epidemiological surveys provide very valuable data on trends in disease patterns, they do not provide answers to test causal relationships and therefore cannot identify the causes for the significant improvements in oral health over the last 40 years. Evidence would indicate, however, that broad societal shifts in population norms and behaviours, combined with changes in clinical diagnostic criteria, treatment planning and clinical procedures are the main reasons for the changes that have taken place. Key implications of the survey results include the need to monitor, support and maintain the good state of oral health of the increasing proportion of younger adults with relatively simple treatment needs. A smaller number of young and middle aged adults but a significant proportion of older adults will have far more complex treatment needs requiring advanced restorative and periodontal care. Future oral health policy will need to address oral health inequalities, encourage skill mix and promote and facilitate the dental profession to deliver appropriate and high quality care relevant to the needs of their local population.


Subject(s)
Dental Health Surveys , Health Policy , Oral Health , Practice Patterns, Dentists' , Adult , Aged , Cariostatic Agents/therapeutic use , Delivery of Health Care , Dental Care , Dental Caries/epidemiology , Fluorides/therapeutic use , Health Behavior , Health Services Needs and Demand , Healthcare Disparities , Humans , Middle Aged , Oral Health/statistics & numerical data , Oral Hygiene/statistics & numerical data , Patient Care Planning , Periodontal Diseases/epidemiology , Quality of Health Care , Social Change , United Kingdom/epidemiology , Young Adult
20.
J Cyst Fibros ; 12(4): 363-6, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23206872

ABSTRACT

INTRODUCTION: Cystic fibrosis (CF) is the most common genetic disorder in Caucasians. Presentation of CF in non-Caucasians is less well studied. OBJECTIVE: This audit was undertaken to determine the phenotypic expression of the 3120+1G>A mutation in black and mixed race children in South Africa. METHODS: A multi-centre retrospective chart review of clinical, laboratory and spirometry data of non-Caucasian CF patients in four CF centres in South Africa was collected. Data was collected at diagnosis and after a five-year follow-up period. Ethical approval was granted for the study. RESULTS: A total of 30 participants were enrolled of whom 14 (47%) were homozygous and 16 (53%) heterozygous for the 3120+1G>A mutation. The mean age of diagnosis was 13 months. Twenty-four (80%) patients had malnutrition (mean weight z-score -3.6) or failure to thrive (77%) at presentation. Twenty (67%) presented with non-specific abdominal symptoms, whilst fifteen (50%) had recurrent respiratory tract infections. Pseudomonas aeruginosa was detected at a mean age of 21 months. The mean FEV1 was 73% predicted (95% CI 54.0-91.1) at study entry and 68% predicted (95% CI 49.74-87.06) at follow-up. CONCLUSION: Failure to thrive and a diagnosis of protein energy malnutrition (kwashiorkor) are the common presenting features of CF in children with the 3120+1G>A mutation. Meconium ileus is a rare presenting feature of CF in black and mixed race children with this deletion in South Africa.


Subject(s)
Black People/genetics , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Cystic Fibrosis/genetics , Mutation , Female , Humans , Infant , Male , Phenotype , Retrospective Studies , South Africa
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