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Biomedical subjects

L Davidson

Publications and source records attributed to L Davidson.

At least 19 recordsLinked to original sources
PubMed1992

Amino acid sequence of the coelomic C globin from the sea cucumber Caudina (Molpadia) arenicola.

The sequence of a globin from a marine invertebrate, the sea cucumber Caudina (Molpadia) arenicola (Echinodermata), is reported. This globin, chain C, is one of four major globins found in coelomic red cells in this organism and is the second to be sequenced. Chain C consists of 157 residues, is amino-terminally acetylated, and has an extended amino-terminal region. This globin shares a 60% sequence identity with the other sequenced C. arenicola globin, D chain (Mauri et al., Biochem. Biophys. Acta 1078, 63-67, 1991), but has a 93.6% identity with a globin from another sea cucumber, Paracaudina chilensis (Suzuki, Biochem. Biophys. Acta, 998, 292-296, 1989).

Amino Acid Sequence↗
PubMed1992

Epidemiology of pediatric trauma: importance of population-based statistics.

To determine the validity of using hospital-based pediatric trauma registry data to draw specific inferences with regard to regional pediatric trauma system design, we compared statistical data on the incidence and mortality of pediatric and adult injuries and burns calculated by the New York State Department of Health, based on legally mandated reports of injury deaths and hospital discharges for 1989. During this year, some 488 children, aged 0 to 14 years, died as a result of injuries, a rate of 13.8 per 100,000 annually, of whom 408 (11.6/100,000) died as a result of traumatic injuries or burns, a population-based rate 20% of that observed in adults. During the same period, 16,402 children were hospitalized for treatment of traumatic injuries and burns, a rate of 465 per 100,000 annually, a population-based rate 56% of that observed in adults; and of this number, some 90 children died, yielding an in-hospital mortality "rate" (ie, case fatality ratio) of 0.55%, and a population-based rate of 2.6 per 100,000 annually. Thus, 9.0 of the 11.6 per 100,000 children who died in New York State in 1989 as a result of traumatic injuries and burns were not admitted to the hospital and, therefore, were unknown to the statewide hospital reporting system.(ABSTRACT TRUNCATED AT 250 WORDS)

Accidents, Traffic↗
PubMed1992

Identification of childhood disability in Jamaica: the ten question screen.

This is the first in a series of papers that report the testing of two instruments for the identification and assessment of childhood disability by community workers (CWs) in Third World countries. It is part of the International Epidemiologic Study on Childhood Disability. The Ten Question Screen (TQ) was used as the main instrument to identify disability in a two stage population-based survey of 5478 children aged 2-9 years in Clarendon, Jamaica. In the second stage, TQ positive and 8% of the screen negative controls were professionally assessed by a doctor and a psychologist using standard criteria based on the main classification system of the ICIDH. Sensitivity of the TQ as a whole varied in different strata of the group and amongst different disabilities, from perfect in girls under 6 years, fits and motor disabilities and for serious disability in all group except boys over 5 years with cognitive disability. Specificity was good but the false positive rate was unacceptably high at 74%. It was concluded, firstly, that the validation of a simple questionnaire of perceptions of behaviour against objective measurements of impairments was perhaps not fair to the TQ. In spite of this, the TQ would be a very useful instrument in collecting disability data or for identifying people in need of rehabilitation help, if a way of reducing false positives could be found.

Child↗
PubMed1992

Sense of self in recovery from severe mental illness.

This report based on research interviews conducted with persons struggling to recover from prolonged psychiatric disorders suggests that the rediscovery and reconstruction of an enduring sense of the self as an active and responsible agent provides an important aspect of improvement. This process of developing a functional sense of self in the midst of persisting psychotic symptoms and dysfunction is described, and its implications for understanding severe mental illness and processes of change are discussed. It is suggested that viewing the development of a dynamic sense of self as central to the improvement process provides a coherent thread which ties together diverse research findings concerning factors influencing course and outcome of illness. It is also suggested that for treatment and rehabilitation to elicit and foster a more functional sense of self, models of improvement will need to allow for, and encourage, a more active and collaborative role for the person with the disorder.

Activities of Daily Living↗
PubMed1992

The promise of partial hospitalization: a reassessment.

In this review of trends in partial hospitalization since 1987, the authors provide a brief overview of the field, summarize recent research findings, examine the data on the growth of partial hospitals, and outline recent changes in public- and private-sector use of this treatment modality. Support for intermediate and long-term partial hospitalization is diminishing rapidly, while support for short-term partial hospitalization as an alternative to inpatient care is increasing in the private sector and diminishing in the public sector. The future for partial hospitals seems uncertain, as the treatment functions of these programs are being assumed by psychosocial and vocational rehabilitation programs and assertive community treatment teams. In light of these trends, the authors recommend new directions for partial hospital research involving comparisons between short-term day hospitalization and intensive outpatient interventions.

Cost Control↗
PubMed1992

Home sweet HEN--a guide to home enteral nutrition.

Initial experience of home enteral nutrition (HEN) was gained from malnourished patients with Crohn's disease. The rationale for HEN was to improve the patients' lifestyle by reducing the need for repeated admissions for nutritional support: this method is extremely useful in correcting nutritional problems. Over the past ten years the use of HEN has expanded to cover other clinical areas including correction of growth retardation secondary to gastrointestinal disease, cystic fibrosis, inborn errors of metabolism, congenital heart disease, and chronic renal failure, in addition to many types of neoplasia and chronic neurological diseases. At the present time, approximately 150 patients receive HEN within the catchment area of the Greater Glasgow Health Board (population 940,000). Despite the increasing availability of HEN many clinicians and dietitians are still reluctant to consider HEN as a 'routine adjunct' to clinical management, claiming that it is too dangerous or complicated. The aims of this article are to explain our method of running a HEN service, offer advice on practical problems and discuss further developments and potential difficulties.

Enteral Nutrition↗
PubMed1991

Suppression of diabetes in nonobese diabetic mice by oral administration of porcine insulin.

Nonobese diabetic (NOD) mice spontaneously develop an autoimmune form of diabetes associated with insulitis. A number of immunomodulatory therapies have been investigated as a treatment for the disease process. Oral administration of the autoantigens myelin basic protein and collagen type II suppresses experimental models of encephalomyelitis and arthritis. We have now found that oral administration of insulin delays the onset and reduces the incidence of diabetes in NOD mice over a 1-year period in animals administered 1 mg of porcine insulin orally twice a week for 5 weeks and then weekly until 1 year of age. As expected, orally administered insulin had no metabolic effect on blood glucose levels. The severity of lymphocytic infiltration of pancreatic islets was also reduced by oral administration of insulin. Furthermore, splenic T cells from animals orally treated with insulin adoptively transfer protection against diabetes, demonstrating that oral insulin administration generates active cellular mechanisms that suppress disease. These results show that oral insulin affects diabetes and the pancreatic cellular inflammatory process in the NOD mouse and raise the possibility that oral administration of insulin or other pancreatic autoantigens may provide a new approach for the treatment of autoimmune diabetes.

Administration, Oral↗
PubMed1991

Amino acid sequence of a globin from the sea cucumber Caudina (Molpadia) arenicola.

Coelomic cells from the sea cucumber Caudina (Molpadia) arenicola contain four major globins, A, B, C and D. The hemoglobins from this organism show unusual ligand-linked dissociation properties. The complete amino acid sequence of the D globin has been established. It is N-acetylated, consists of 158 residues and has a 10 amino acid N-terminal extension similar to that found in some other invertebrate globins. The C. arenicola D globin has an equal sequence identity (28%) with both alpha and beta human globins and as anticipated, is more closely related to these vertebrate proteins than are molluscan globins. The C. arenicola D globin shows a 59% identity with the globin I from the sea cucumber Paracaudina chilensis. The availability of the C. arenicola D globin sequence will aid the X-ray analysis of this protein and facilitate an understanding of the changes in subunit interactions that occur with cooperative ligand binding.

Amino Acid Sequence↗
PubMed1991

Effect of variation in infusion time and macrophage blockade on organ uptake of amphotericin B-deoxycholate.

Amphotericin B is administered as a colloidal suspension due to its insolubility in water. Macrophages, particularly those in the liver, have been implicated as the predominant cell type responsible for the uptake of colloidal amphotericin B. We examined the effect of infusion time and macrophage function to confirm the role of the macrophage in the uptake of amphotericin B. Prolonged infusion time (24 h compared to 6 h) resulted in significantly less hepatic and splenic accumulation of amphotericin B. Blockade of macrophage function with methylpalmitate also resulted in significantly decreased hepatic and splenic uptake of amphotericin B. Uptake of amphotericin B by lung macrophages was not significantly affected by methylpalmitate. The area under the serum concentration versus time curve was significantly higher in the group that received methylpalmitate compared to either the 6 or 24 h amphotericin B infusion groups. These results suggest that fixed macrophages play an important part in the pharmacokinetics of amphotericin B, and that increasing drug solubility may alter the pharmacokinetics of amphotericin B.

Amphotericin B↗
PubMed1991

Idiopathic gastroparesis is associated with a multiplicity of severe dietary deficiencies.

UNLABELLED: Idiopathic gastroparesis (IG), a disorder characterized by abnormally delayed emptying of food from the stomach, is associated with many symptoms that could have an impact on dietary intake. The intake of dietary protein, carbohydrate, fat, fiber, vitamins, and minerals was prospectively evaluated in patients with symptomatic IG and compared with asymptomatic controls. Twenty-four patients and 24 age- and sex-matched controls completed a detailed 7-day diet record while consuming a self-selected diet. Dietary information was entered into a computer and analyzed using the Nutranal program. Results were expressed as daily intake and percent recommended dietary allowance (%RDA) when applicable. Patients consumed a diet containing fewer calories than would have been predicted based on age, height, sex, frame, and weight (85% of calculated energy expenditure vs 100%) for controls. Although patients with IG consumed significantly fewer calories than controls (1112 kcal vs 1431 kcal), the proportion of fat (32% vs 34%), carbohydrate (49% vs 48%), and protein (17% vs 16%) was similar in the two groups. Intake of vitamins B6, vitamin C, folate, niacin, riboflavin, thiamine, calcium, copper, iron, magnesium, phosphorus, and zinc were below the %RDA. Intake of vitamin B12, vitamin C, folate, thiamine, niacin, magnesium, phosphorus, and zinc were significantly less than controls. Vitamin A intake was above the RDA and not different from that of controls. Prolonged t1/2 of solids correlated with diminished intake of protein, iron, niacin, and potassium. They correlated inversely with serum albumin in patients with idiopathic gastroparesis. CONCLUSION: Although eating less, patients with IG do not consistently alter the proportion of fat, carbohydrate, and protein in their diets. Because their diet is markedly deficient in a number of essential vitamins and minerals, dietary evaluation and counseling is suggested for all patients with idiopathic gastroparesis.

Adult↗
PubMed1989

Solubility and stability of amphotericin B in human serum.

The solubility and stability of amphotericin B in human serum in vitro was assessed using a sensitive high performance liquid chromatographic technique. The solubility of amphotericin B at concentrations ranging from 0.5 micrograms/ml to 10 micrograms/ml in human serum at pH 7.4, at 37 degrees C, and in 5% CO2 (simulated in vivo conditions) showed no significant difference compared with the solubility at 23 degrees C in room air after a 1 h incubation period. Dissolution of the colloidal suspension at a concentration of 2 micrograms/ml reached 81% in 3 min with a small increase in solubility by 60 min. Amphotericin B was very stable (less than 5% loss) in human serum at -20 degrees C for up to 14 days with only a 10% loss of drug at 6 months. In dimethylsulfoxide, however, losses at 6 months were greater than 60%. We conclude that amphotericin B solubilizes, but not completely, from a colloidal form in human serum under simulated in vivo conditions at 37 degrees C and at 23 degrees C in room air over 1 hour. Additionally, amphotericin B is stable in frozen serum for 6 months.

Amphotericin B↗