Search PubMed⌕ Search

Biomedical subjects

J Stevenson

Publications and source records attributed to J Stevenson.

At least 91 records · Page 5Linked to original sources
PubMed1996

The impact of the standards for pediatric immunization practices on vaccination coverage levels.

OBJECTIVE: To assess the impact on clinic-specific vaccination coverage of implementing the Standards for Pediatric Immunization Practices. DESIGN: A nonrandomized intervention trial conducted for 1 year. SETTING: Two public health clinics in Albuquerque, NM: 1 intervention site and 1 control site, each serving 1 of 4 city quadrants. PARTICIPANTS: All children enrolled in the 2 city public health clinics. INTERVENTIONS: Implementation of the Standards for Pediatric Immunization Practices. OUTCOME MEASURES: Assessment of up-to-date vaccination coverage levels prior to and at the conclusion of the project. The impact on the proportion of children who dropped out of vaccination services after receiving 1 dose by 3 months of age. RESULTS: At the intervention site, up-to-date coverage at 12 months of age rose from 57.5% to 80.4%, while levels at the control site decreased from 42.1% to 41.9%. Before the intervention, 24% of children at the intervention site who received the first dose of diphtheria and tetanus toxoids and pertussis vaccine (DTP 1) by 3 months of age failed to receive the third dose of DTP (DTP 3) by 12 months of age vs 5% after the intervention. At the control site, the proportion of children who received DTP 1 by 3 months of age, but not DTP 3 by 12 months of age, increased from 39% to 51%. CONCLUSION: Implementation of the Standards for Pediatric Immunization Practices in a public health clinic was associated with important increases in vaccination coverage levels and a reduction in the proportion of children who dropped out of vaccination services.

Child↗
PubMed1996

Outbreak of Escherichia coli O157 phage type 2 infection associated with eating precooked meats.

Fourteen cases of Escherichia coli O157 infection were reported to the consultant in communicable disease control in Sunderland Health Authority in August 1995. E. coli O157 phage type 2, Vero cytotoxin 2 was isolated from the faeces of ten cases. Nine of the isolates were indistinguishable by Vero cytotoxin subtyping and analysis of chromosomal DNA. Two cases with haemolytic uraemic syndrome were confirmed serologically and two cases remained unconfirmed. A case control study showed infection with E. coli O157 to be associated with having eaten precooked meats from a single shop. Environmental investigations at the shop showed that cooked meats were stored close to raw beef, raw meats were left on preparation surfaces, and the same staff served both raw and cooked meats. This outbreak draws attention to standards of food preparation and handling in outbreaks of E. coli O157, the issue of cross contamination, and the need to improve local surveillance of haemolytic uraemic syndrome.

Adolescent↗
PubMed1996

Changes in heritability across increasing levels of behavior problems in young twins.

The present study addresses the issue of differential heritability with increasing severity of parent-reported internalizing and externalizing behavior problems assessed by the Child Behavior Checklist. The sample includes 526 identical and 389 fraternal same-sexed twin pairs from five national birth cohorts, aged 5-6, 8-9, and 12-15 years. Heritability (h2), common environment (c2), and changes in these parameters as a function of proband score were analyzed by multiple regression models (Cherny et al., 1992). Internalizing and externalizing behavior showed significant heritability. A small increment in h2 and a reduction of c2 with increasing severity of externalizing behavior were independent of sex and age. For internalizing behavior h2 increased and c2 declined with increasing severity for the 5-6 and 8-9 year olds. Logarithmic transformation of scores lowered h2 and increased c2, particularly for externalizing behavior. The changes in heritability with severity were nonsignificant for the transformed variables.

Adolescent↗
PubMed1996

An audit of the organisation of neonatal screening for phenylketonuria and congenital hypothyroidism in the Northern Region.

BACKGROUND: The objectives of the study were to identify whether all districts in the Northern Region had a system in place to ensure that all resident babies were being screened for phenylketonuria and congenital hypothyroidism and to identify potential delays which could influence whether a result was available on all residents before 28 days of age. METHODS: Lead professionals involved in the screening programmes were interviewed in 1993 in all 16 districts. Recommendations for improving the service were made to each district. Six months later a follow up telephone interview with the doctor involved in the screening programmes was undertaken to identify the changes that had been made in the service. RESULTS: In 1993 three districts made no attempt to match neonatal screening results to birth notifications. Of the 13 districts that undertook matching, two districts did no further checks to identify babies without a result and five districts undertook a check on a monthly basis only. Only six districts were, therefore, found to have a timely fail-safe system for checking that results were available for resident babies. In 1994, following recommendations to improve the timeliness and completeness of the screening programmes, all districts except two had improved their fail-safe systems. CONCLUSION: This multi-disciplinary regional audit resulted in organisational improvements to the neonatal metabolic screening programmes in the Northern Region.

Appointments and Schedules↗
PubMed1996

Exogenous glutamate concentration regulates the metabolic fate of glutamate in astrocytes.

The metabolic fate of glutamate in astrocytes has been controversial since several studies reported > 80% of glutamate was metabolized to glutamine; however, other studies have shown that half of the glutamate was metabolized via the tricarboxylic acid (TCA) cycle and half converted to glutamine. Studies were initiated to determine the metabolic fate of increasing concentrations of [U-13C] glutamate in primary cultures of cerebral cortical astrocytes from rat brain. When astrocytes from rat brain were incubated with 0.1 mM [U-13C] glutamate 85% of the 13C metabolized was converted to glutamine. The formation of [1,2,3-13C3] glutamate demonstrated metabolism of the labeled glutamate via the TCA cycle. When astrocytes were incubated with 0.2-0.5 mM glutamate, 13C from glutamate was also incorporated into intracellular aspartate and into lactate that was released into the media. The amount of [13C] lactate was essentially unchanged within the range of 0.2-0.5 mM glutamate, whereas the amount of [13C] aspartate continued to increase in parallel with the increase in glutamate concentration. The amount of glutamate metabolized via the TCA cycle progressively increased from 15.3 to 42.7% as the extracellular glutamate concentration increased from 0.1 to 0.5 mM, suggesting that the concentration of glutamate is a major factor determining the metabolic fate of glutamate in astrocytes. Previous studies using glutamate concentrations from 0.01 to 0.5 mM and astrocytes from both rat and mouse brain are consistent with these findings.

Alanine↗
PubMed1996

Genetic influence on parent-reported attention-related problems in a Norwegian general population twin sample.

OBJECTIVE: To assess the genetic and environmental influences on attention problems in a general population twin sample and to investigate whether there are changes in the relative genetic influence on attention problems with increasing severity. METHOD: Parental ratings of the Child Behavior Checklist were collected from five Norwegian national cohorts of same-sex twins. The sample comprises 526 identical and 389 fraternal pairs. RESULTS: Considerable genetic influence on attention problems was found for both sexes and across age groups (aged 5 to 9 years and 12 to 15 years). A two-parameter model with additive genetic influence and nonshared environment showed a good fit, with heritability ranging from .73 in boys aged 5 to 9 years, to .76 in girls aged 5 to 9 years. There was no change in the relative genetic influence across severity after accounting for the influence of cerebral palsy, epilepsy, and low birth weight. CONCLUSION: The results indicate a substantial genetic influence on attention problems across sex, age, and severity.

Adolescent↗
PubMed1996

An unusual cause of hiccups.

A case of persistent hiccup associated with cavitating pulmonary tuberculosis is reported. Though tuberculosis presenting with hiccup is rare, tuberculosis is again on the increase and clinicians should remain alert to the possibility of this diagnosis.

Antitubercular Agents↗
PubMed1996

Mental health of preschool children and their mothers in a mixed urban/rural population. I. Prevalence and ecological factors.

BACKGROUND: The prevalence rate of behaviour problems and maternal mental disturbance was estimated using a sample of 1047 families with a 3-year-old child from a mixed urban/rural area. METHOD: Parents completed the Child Behaviour Checklist, EAS Temperament Questionnaire, Weiss-Werry-Peters Activity Scale and the GHQ-30. RESULTS: The rate of behaviour problems (13.2%) was similar to that obtained in studies of urban children. The rate of maternal disturbance (27.6%) was lower than in other population samples. Few differences were found in the prevalence rates in the urban and rural areas. CONCLUSIONS: Preschool children and their parents living in non-urban areas had the same rates of problems as those in conurbations. The service needs of such families are similar regardless of locality.

Attention Deficit Disorder with Hyperactivity↗
PubMed1996

Mental health of preschool children and their mothers in a mixed urban/rural population. II. Family and maternal factors and child behaviour.

BACKGROUND: The extent to which certain maternal, child and family characteristics are associated in families with a 3-year-old child were examined. METHOD: A total population of families with a 3-year-old child and living in the New Forest were identified. Measures of child behaviour and the maternal GHQ-30 were obtained. RESULTS: Whereas behaviour problems were found to be significantly associated with all maternal and family factors (except social class), difficult temperament was only related to mother's recall of their own childhood as unhappy and overactivity was only significantly associated with maternal disturbance. CONCLUSIONS: The results are consistent with maternal disturbance and difficult temperament acting independently and additively to influence the development of behaviour problems in preschool children.

Child Behavior Disorders↗
PubMed1996

Mental health of preschool children and their mothers in a mixed urban/rural population. III. Latent variable models.

BACKGROUND: There is a lack of clear and explicit models of the way various family and social influences on children's behaviour interact with factors such as temperament to produce behaviour disturbance in young children. METHOD: The following measures had been obtained on a total population sample of 1047 families with a 3-year-old child: the child's perceived cuddliness, difficult temperament, mother's unhappy childhood, maternal disturbance, social class, behaviour problems and overactivity. A latent variable analysis using the LISREL 7 program was applied to the data. RESULTS: A model that allowed the latent variables child 'temperament' and 'mother's mental state' to have separate additive effects on 'child adaptation' proved an excellent fit (goodness of fit index = 0.956). This model suggests that there is a common factor ('child adaptation') underlying behaviour problems and overactivity. Using this model 72% of child adaptation in boys could be explained. For girls however temperament and mother's mental state accounted for only 30% of the variance in child adaptation. CONCLUSION: There is a need to investigate different mechanisms for the origins of behaviour problems in preschool boys and girls.

Attention Deficit Disorder with Hyperactivity↗
PubMed1996

Progress toward integrating hepatitis B vaccine into routine infant immunization schedules in the United States, 1991 through 1994. Connecticut Hepatitis B Project Group.

OBJECTIVE: We assessed progress toward universal infant immunization against hepatitis B, which was first recommended in November 1991. METHODS: Multiple data sources were used to describe vaccination policies and trends in infant hepatitis B vaccine coverage. RESULTS: As of June 1993, 51% of the 63 local, state, and territorial immunization programs recommended hepatitis B vaccination of all newborns shortly after birth. The number of first dosages of hepatitis B vaccine administered to infants in public sector clinics increased rapidly from late 1992 to 1993, and at the end of 1993 was approximately two thirds the number of first dosages of other infant antigens. In a nationwide survey of hospital nurseries 47% offered hepatitis B vaccine to all newborns. Of 3982 sampled newborns in these hospitals, 36.2% had been vaccinated before discharge. In San Francisco and Connecticut, where public health officials encouraged hospitals to offer hepatitis B vaccination, first-dose coverage at discharge was 82.3% in 1994 and 69.1% in 1993, respectively. Coverage was higher in healthier infants and lower in infants of older or better-educated mothers. Results from the National Health Interview Survey demonstrate that three-dose completion at 12 months of age increased form less than 1% of children born in 1989 to 40% of children born in the fourth quarter of 1992. Vaccination at birth increased from less than 1% of infants born in 1989 to 32% of infants born in the second half of 1993. CONCLUSIONS: Infant hepatitis B vaccination has expanded rapidly since national recommendations were made; however, universal coverage has not been achieved.

Connecticut↗
PubMed1996

Modulation of central nervous system metabolism by macromolecules: effects of albumin and histones on glucose oxidation by synaptosomes.

Since increasing evidence suggests that several proteins play a significant role in the regulation of glucose oxidation in the central nervous system, a series of experiments was designed to determine the specific proteins involved and to delineate their possible mode of action. In these studies, the rate of substrate oxidation by isolated synaptosomes in vitro was determined by measuring the production of [14C]carbon dioxide from labeled compounds in the presence and absence of the added protein. In the initial experiments, an examination of a broad selection of pure proteins revealed that only albumin (bovine serum albumin [BSA]) or histones (at concentrations of 100 micrograms/mL or less) exhibited an inhibitory effect of greater than 60% on the rate of glucose oxidation. Furthermore, isolated cell fractions P1 (nuclei and cellular debris), P2 (mitochondria, synaptosomes, and myelin), and other membrane proteins had little or no effect on the rate of [14C]carbon dioxide production from [6(14)C]glucose. When either BSA or histones were treated with trypsin, the inhibitory effects were eliminated. To determine whether these effects were related to changes in substrate transport, we measured the rate of glucose uptake by synaptosomes using [6(14)C]glucose, [1,2-3H]2-deoxyglucose, and [3H]3-O-methylglucose in the presence of 5% serum protein. These experiments revealed that the rate of glucose transport was not affected by serum proteins. Collectively, these results indicate that albumin and histones attenuate the rate of glucose oxidation by synaptosomes. The results also support the conclusion that the intact protein molecule is required for this inhibition, since treatment with trypsin abolished this effect. It can also be concluded that this effect is not at the site of transport and that the protein(s) are acting either directly at intercellular site(s) or indirectly via specific messengers.

Animals↗
PubMed1995

HeLa plasma membranes bind the antitumor sulfonylurea LY181984 with high affinity.

Homogenates, total particulate and plasma membranes of cultured HeLa S cells bound the tritiated antitumor sulfonylurea [3H]LY181984 with high affinity (Kd of 20 to 50 nM). Highest affinity binding (Kd of 25 nM) was to purified plasma membrane. The number of binding sites, estimated to represent 30 to 35 pmol/mg protein, would represent a low abundance constituent representing about 1/1000 of the total plasma membrane proteins. When corrected for mitochondrial uptake, binding recoveries of about 80% were achieved. Of the recovered specific radioactivity bound, approximately 90% was associated with the total particulate fraction. Of this, nuclei- and plasma membrane-free total membranes bound little or no [3H]LY181984 with high affinity. The high-affinity binding was restricted primarily to the plasma membranes. All fractions exhibited varying degrees of lower affinity binding indicative of a heterogeneous array of components capable of binding [3H]LY181984 at high concentrations of LY181984. Enrichment of 5-fold over total homogenates of high-affinity binding compared favorably to a 6.7-fold enrichment of the plasma membrane marker enzyme 5'-nucleotidase determined in parallel. We conclude that plasma membranes of HeLa cells contain high-affinity binding sites of low abundance for the antitumor sulfonylurea LY181984 and that the high-affinity sites are associated predominantly with the plasma membrane.

Antineoplastic Agents↗
PubMed1995

Schedule for oral-motor assessment (SOMA): methods of validation.

The Schedule for Oral Motor Assessment (SOMA) was developed for the purpose of objectively rating the oral-motor skills of preverbal children, with a view to identifying areas of deficient abilities that could have clinical significance. The instrument can be administered without special equipment, by a trained observer. Oral-motor function is assessed across a range of food textures and fluids. Ratings of oral-motor skills are largely made post hoc by analysis of a videorecording of the test administration. The test-retest and interrater reliability of the instrument have been shown to be excellent. Criterion validity was investigated by means of a novel 'seeded cluster analysis' procedure in which 127 young children were assessed, most of whom were between 8 and 24 months of age. Ten percent of the sample had known abnormal oral-motor function in association with cerebral palsy (ages between 12 and 42 months). Not only was criterion validity satisfactorily established by the analysis but an abbreviated version of the SOMA--suitable for screening purposes--was developed. This has been shown to have a positive predictive validity greater than 90% and sensitivity greater than 85% for the detection of infants with clinically significant oral-motor dysfunction.

Cerebral Palsy↗