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Richard Scott

Publications and source records attributed to Richard Scott.

22 records · Page 2Linked to original sources

An in vitro method for comparing biocompatibility of materials for extracorporeal circulation.

UNLABELLED: We measured the response of fresh heparinized human blood to recirculation through circuits made of LVA (Portex Industries, Hythe, Kent, UK), SRT (Rehau UK, Langley, Slough, UK) and Tygon S-65-HL (Norton Performance Plastics, Corby, Northants, UK), as control. Circuit construction: 1/2 in. tubing, heat exchanger (Dideco D-720P), Stockert roller pump, just underoccluded, Cincinnati Sub Zero heater, circuit volume of 500 ml. Flow 3.45 l/min, 37 degrees C. SAMPLES: at 10 min, 1, 2, 4 and 6 h. n=5 in each group; 2/5 SRT experiments were stopped at 45 and 60 min due to overpressurization. RESULTS: Baseline activated clotting time (ACT) of 300 s, increasing in all groups as fibrinogen fell to zero with SRT and LVA. Minimum fibrinogen was 1 g/l for Tygon. Absolute thrombocytopenia occurred (SRT and LVA 60 min and Tygon 240 min). International normalized ratio (INR) in both the SRT and LVA circuits increased, but mean increase for Tygon (0.56) was smaller than the other two materials. Plasma free haemoglobin increased in all three materials; the increase was greater in the LVA circuits compared to the control. C5b9 levels increased equally in all groups. Lactoferrin levels rose equally in all groups to a maximum at 150 min. The neutrophil counts fell, mirroring the lactoferrin. The total white cell counts also fell in all groups; in the LVA circuits, the fall was significantly lower than in the control. Rapid disappearance of platelets and fibrinogen from the blood in the SRT and LVA circuits excludes them both from extracorporeal use. Paradoxically, SRT caused the least complement activation of the three materials. This method can be used to compare biocompatibility.

Adolescent↗

Hunger: its impact on children's health and mental health.

OBJECTIVE: Hunger, with its adverse consequences for children, continues to be an important national problem. Previous studies that document the deleterious effects of hunger among children cannot distinguish child from family hunger and do not take into account some critical environmental, maternal, and child variables that may influence child outcomes. This study examines the independent contribution of child hunger on children's physical and mental health and academic functioning, when controlling for a range of environmental, maternal, and child factors that have also been associated with poor outcomes among children. METHODS: With the use of standardized tools, comprehensive demographic, psychosocial, and health data were collected in Worcester, Massachusetts, from homeless and low-income housed mothers and their children (180 preschool-aged children and 228 school-aged children). Mothers and children were part of a larger unmatched case-control study of homelessness among female-headed households. Hunger was measured by a set of 7 dichotomous items, each asking the mother whether she has or her children have experienced a particular aspect of hunger during the past year--1 concerns food insecurity for the entire family, 2 concern adult hunger, and 4 involve child hunger. The items, taken from the Childhood Hunger Identification Project measure, are summed to classify the family and divided into 3 categories: no hunger, adult or moderate child hunger, or severe child hunger (indicating multiple signs of child hunger). Outcome measures included children's chronic health condition count using questions adapted from the National Health Interview Survey, Child Health Supplement, and internalizing behavior problems and anxiety/depression, measured by the Child Behavior Checklist. Additional covariates included demographic variables (ie, age, gender, ethnicity, housing status, number of moves, family size, income), low birth weight, child life events (ie, care and protection order, out of home placement, abuse, severe life events count), developmental problems (ie, developmental delay, learning disability, emotional problems), and mother's distress and psychiatric illness. Multivariate regression analyses examined the effect of child hunger on physical and mental health outcomes. RESULTS: The average family size for both preschoolers and school-aged children was 3; about one third of both groups were white and 40% Puerto Rican. The average income of families was approximately $11 000. Among the school-aged children, on average 10 years old, 50% experienced moderate child hunger and 16% severe child hunger. Compared with those with no hunger, school-aged children with severe hunger were more likely to be homeless (56% vs 29%), have low birth weights (23% vs 6%), and have more stressful life events (9 vs 6) when compared with those with no hunger. School-aged children with severe hunger scores had parent-reported anxiety scores that were more than double the scores for children with no hunger and significantly higher chronic illness counts (3.4 vs 1.8) and internalizing behavior problems when compared with children with no hunger. There was no relationship between hunger and academic achievement. Among preschool-aged children, who averaged 4 years of age, 51% experienced moderate child hunger and 8% severe child hunger. For preschoolers, compared with children with no hunger, severe hunger was associated with homelessness (75% vs 48%), more traumatic life events (8.5 vs 6), low birth weight (23% vs 6%), and higher levels of chronic illness and internalizing behavior problems. Mothers of both preschoolers and school-aged children who reported severe hunger were more likely to have a lifetime diagnosis of posttraumatic stress disorder. For school-aged children, severe hunger was a significant predictor of chronic illness after controlling for housing status, mother's distress, low birth weight, and child live events. For preschoolers, moderate hunger was a significant predictor of health conditions while controlling for potenns while controlling for potential explanatory factors. For both preschoolers and school-aged children, severe child hunger was associated with higher levels of internalizing behavior problems. After controlling for housing status, mother's distress, and stressful life events, severe child hunger was also associated with higher reported anxiety/depression among school-aged children. CONCLUSION: This study goes beyond previous research and highlights the independent relationship between severe child hunger and adverse physical health and mental health outcomes among low-income children. Study findings underscore the importance of clinical recognition of child hunger and its outcomes, allowing for preventive interventions and efforts to increase access to food-related resources for families.

Adolescent↗

Camptocormia treated with bilateral pallidal stimulation.

The authors report the neurological, neurophysiological, and neuropsychological effects of using long-term bilateral pallidal high-frequency deep brain stimulation (DBS) in a case of disabling camptocormia. Deep brain stimulation electrodes were implanted stereotactically to target the globus pallidus internus (GPi) bilaterally. Local field potentials (FPs) were recorded using the DBS electrodes and concurrent abdominal flexor electromyography (EMG) potentials during camptocormic episodes. Videotaped assessments of the movement disorder and neuropsychological evaluations of the patient before implantation and 6 months after initiation of pallidal stimulation were recorded. There was significant functional improvement following long-term pallidal stimulation, and some improvement was noted in neuropsychological scores. A temporal correlation between the GPi FPs and EMG-recorded rectus abdominis potentials was evident. There were no treatment-related adverse effects. The authors have found that long-term pallidal stimulation was safe and offered functional benefit to a patient with this severely disabling condition. The physiological studies may help further the understanding of the pathophysiology of this rare entity.

Adult↗