Biomedical subjects

A L Wright

Publications and source records attributed to A L Wright.

At least 19 recordsLinked to original sources

PubMed2006

Eye-hand co-ordination skills in very preterm infants <29 weeks gestation at 3 years: Effects of preterm birth and retinopathy of prematurity.

INTRODUCTION: Preterm infants are known to have low gross motor and fine motor skills. We questioned whether poor eye-hand coordination skills are associated with moderate to severe stages of Retinopathy of Prematurity (ROP). AIMS: The aim of this study was to examine development, with specific reference to eye-hand coordination skills, among preterm infants <29 weeks gestation with different stages of ROP at 3 years of age. METHODS AND MATERIALS: Fifteen preterm infants (<29 weeks gestation) who developed Stage 3 ROP were matched for gestation, birthweight and gender with infants who developed Stage 2 and Stage 1/no ROP. Developmental (Griffiths Mental Development Scales and Peabody Developmental Motor Scales) and ophthalmic assessments in the 3 matched groups of 15 were performed at 3 years of age. RESULTS: 1) Whilst the eye-hand coordination scores and Peabody fine motor scores were lower in the Stage 3 ROP group, they were not significantly lower than the other ROP groups. 2) Locomotor, Peabody gross motor skills and hearing and speech were significantly lower in the infants with Stage 3 ROP. The other developmental domains were not significantly different to the severe ROP group. 3) All 3 groups (of preterm infants) had lower eye-hand coordination and Peabody fine motor scores compared to test norms. 4) There were 8 of 15 infants with Stage 3 ROP who developed moderate visual problems by 3 years of age. CONCLUSION: In preterm infants, low eye-hand coordination/fine motor scores are likely to be due to their extreme prematurity.

Child, Preschool↗

PubMed2006

Postnatal development of a large auditory nerve terminal: the endbulb of Held in cats.

The endbulbs of Held are formed by the ascending branches of myelinated auditory nerve fibers and represent one of the largest synaptic endings in the brain. Most of the developmental changes in structure occur during the first 30 postnatal days of age. The neonatal endbulb begins as a flattened expansion with many filopodia, resembling a growth cone and characterized by numerous puncta adherentia and synapses associated with small postsynaptic densities; the most impressive feature of the ending at this age is its highly irregular plasma membrane that interdigitates with that of the postsynaptic spherical bushy cell. During these first 30 days, the number of puncta adherentia diminishes, postsynaptic densities nearly double in size, intermembraneous cisternae emerge, and plasma membranes flatten. These features endow the endbulb with an adult-like appearance. On the other hand, synaptic vesicle density increases progressively from approximately 50/microm2 at birth to 100/microm2 at adulthood. Mitochondria size remains constant over this developmental period but mitochondrial volume fraction increases until 60 days postnatal. Although many features of endbulb morphology stabilize by 30 days, other features suggest that endbulb development continues into the third month of age. Many of these observations correlate with the maturation of physiological response properties and suggest issues for further study.

Aging↗

PubMed2006

The impact of CD14 polymorphisms on the development of soluble CD14 levels during infancy.

CD14 is a receptor involved in the recognition of lipopolysaccharide and other bacterial wall components that may be involved in the balance between infectious and allergic disease and the early polarization towards TH1. Our group has shown an association between polymorphisms in the 5' flanking region of the CD14 gene and plasma soluble CD14 (sCD14) levels at 11 years of age. However, whether this association is present at birth and in infancy remains to be determined. In this study, we measured sCD14 levels in plasma from the umbilical cord (n = 387) and at 3 months (n = 357) and 1 year (n = 312) of age in non-selected healthy infants to assess their relationship with CD14 genotypes at -4190, -2838, -1720 and -260 (relative to translation start site). There was no relation of CD14 genotypes with sCD14 at birth. However, there was a significant association between CD14 genotypes and sCD14 as early as 3 months. Longitudinal analysis suggests that CD14 polymorphisms modulate sCD14 levels up to 1 year of age. This association early in life may have an impact on TH1 polarization and subsequent protection against allergic disease.

Cross-Sectional Studies↗

PubMed2004

Dynamic changes in sensitization to specific aeroallergens in children raised in a desert environment.

BACKGROUND: Allergen skin test reactivity and total serum IgE are objective measures used to characterize and help diagnose allergic diseases. Cross-sectional studies have shown that overall aeroallergen skin test reactivity increases throughout childhood. However, little attention has been paid to whether individual aeroallergen remittance occurs, which could distort or mask relationships to disease. OBJECTIVE: To access the incidence and remittance of skin test reactions to individual allergens in children aged 6-11 years. METHODS: Longitudinal sensitization to six aeroallergens and total IgE were assessed in 828 children raised in the semi-arid US southwest at ages 6 and 11 years. RESULTS: New sensitization (to any allergen) between 6 and 11 years occurred in 30.2% of children compared with 39.7% before age 6 years. The rate of complete remittance from positive to negative between ages 6 and 11 years was 8.2%, and total IgE at age 6 years was not predictive. Remittance rates for individual allergens were high and variable (19-49%). The perennial allergens Bermuda and Alternaria were early sensitizers and had low remittance rates. Early sensitization to the four seasonal allergens was less common and more subject to remittance with the bulk of sensitization occurring between 6 and 11 years. CONCLUSION: This study shows that sensitization to individual aeroallergens in childhood is dynamic and indicates the limitation of single point assessment of skin test reactivity.

Air↗

PubMed2003

A case of childhood dermatofibrosarcoma protuberans without detected cytogenetic abnormality.

Dermatofibrosarcoma protuberans (DFSP) is a rare, infiltrative skin tumour of intermediate malignancy, with a limited potential for metastasis but a high rate of recurrence; specific cytogenetic abnormalities are now known. Childhood DFSP has been considered a rarity in the past, but it is now recognized that many cases of childhood DFSP are diagnosed only in adulthood. Despite advances in the understanding of its pathogenesis as well as the development of valuable immunohistochemical and cytogenetic diagnostic techniques, there often remains a significant delay between the initial presentation and diagnosis of DFSP. We report a case of childhood DFSP in which the diagnosis was reached only after a nodular lesion developed in a plaque that was initially present. Causes for delay between initial presentation and diagnosis in childhood DFSP are discussed. Histology and immunostaining in our patient showed the typical features of DFSP, but the G-banded cytogenetic analysis of short-term tissue culture was negative. However, this technique offers only a detection rate between 50% and 80%. Clinicians should be aware of the limitations of newer diagnostic techniques. Increasing recognition amongst paediatricians and paediatric dermatologists that childhood DFSP is not as rare as once believed will probably lead to the use of newer diagnostic methods at an earlier stage, and so reduce the delay between the onset of symptoms and diagnosis.

Biopsy↗

PubMed2002

The association between persistent eosinophilia and asthma in childhood is independent of atopic status.

BACKGROUND: Although peripheral blood eosinophilia is associated with risk of asthma, the relation with atopy has not been established. OBJECTIVE: To assess the relationship between eosinophils and chronic asthma in childhood, and to determine the factors associated with eosinophil levels over time. METHODS: Percent eosinophils/300 white blood cell (WBC) count ('eos') was measured at 9 months, 6 years and 11 years in subjects participating in the prospective Tucson Children's Respiratory Study. Children were classified based on the number of measurements in which they had low (< or = 2%) or high (>5%) eosinophils, as follows: (1) Persistently low eos (n = 130); (2) Low eos (intermittently low or consistently moderate, but never high, n = 317); (3) Intermittently high eos (n = 192); and (4) Persistently high eos (n = 17). Only children with > or = 2 eos measurements were included in the analysis. Chronic asthma was defined as medical doctor (MD)-diagnosed asthma with reports of wheezing during the previous year, on > or = 3 questionnaires completed between 2 and 13 years of age. Children with at least one positive skin prick test (SPT; > or = 3 mm) at age 6 or 11 were considered 'atopic'. RESULTS: Chronic asthma was linearly related to longitudinally ascertained eosinophils (trend chi2 P<0.001) with prevalence ranging from 5.8% among children with persistently low eos to 37.5% among children with persistently high eos. This relation was independent of atopy. Parental history of asthma was associated with both chronic asthma (P <0.001) and with longitudinal eosinophil status (P < 0.001). After adjusting for atopy and gender, there was a 70% increase in asthma risk with each increase in longitudinal eosinophil level. This stepwise increase was reduced to 48% when parental asthma was added to the model. CONCLUSION: Longitudinal eosinophil levels are linearly associated with chronic asthma in childhood, independent of atopy. The strong association between parental asthma and eosinophil status suggests that genetic background may be an important determinant of eosinophilic response.

Asthma↗

PubMed2001

The association of allergic sensitization in mother and child in breast-fed and formula-fed infants.

Human milk contains immunologically active substances potentially capable of altering infant immune response. As part of the prospective Children's Respiratory Study, we assessed whether the association between maternal allergic status and allergic status of the child was altered by breast-feeding. Skin-prick tests for 7 common allergens were administered to 702 6-year-old children and their mothers. The percentage of children sensitized to specific allergens, maternal skin test response to that allergen, and whether or not the child was ever breast-fed was determined. Findings indicated that specific sensitization in the mother was associated with specific sensitization in the child only if the child was breast-fed. This indirectly supports the hypothesis that contents of milk differ with maternal allergic status, and appear to affect allergic status in the child. These results suggest that milk from allergic mothers either promotes a Th2 type immune response or suppresses Th1 immune response in the child.

Allergens↗

PubMed2001

The rise of breastfeeding in the United States.

What factors influenced the resurgence of breastfeeding in the last decades of the twentieth century? This article has considered several explanations. Demographic trends, particularly the increased birth rate among black and Hispanic women, coupled with the resurgence of breastfeeding in these groups, may have contributed to the increase in the breastfeeding rate during the 1990s but likely played a minimal role in the earlier, more dramatic increase. The decrease in breastfeeding in the earlier part of the twentieth century may be partly attributable to increased maternal employment, but the resurgence of breastfeeding occurred during the late twentieth century--a period of unprecedented influx of new mothers into the workforce. There is no evidence that health care practitioners are providing more support for breastfeeding, and most international and US policies postdated the resurgence of breastfeeding, although they may have influenced the increase in the 1990s. A more plausible explanation of the resurgence of breastfeeding in all major segments of society is the pervasive influence of the natural-childbirth movement of the 1960s and 1970s, with its effects on the standard management of childbirth. Also, the increase in breastfeeding among low-income women may be attributable partly to programmatic changes in the provision of supplemental food through the WIC program and the targeting of breastfeeding-promotion efforts to the specific concerns of these women. Although breastfeeding increased at the end of the twentieth century relative to earlier decades, the disparity between the recommended rates and those achieved by US women is great. Thus, efforts to increase breastfeeding initiation and duration should continue, particularly for the groups that are at greatest risk for illness, such as minority and low-income infants. This article suggests that the strategies likely to have a lasting effect on future breastfeeding rates will be social pressures that affect existing barriers to breastfeeding. Such pressures may come from health maintenance organizations, insurance companies, and the US government, which are likely to increasingly recognize the costs of not breastfeeding to their institutions. The provision of flexible work hours and paid maternity leave, either by the US government or family-friendly workplaces, could increase the ability of employed women to optimally feed their infants. As Retsinas noted in an article on the cultural context of breastfeeding, "While it is 'known' that breastfeeding is better, our society is not structured to facilitate that choice." Efforts to improve breastfeeding rates need to make visible the wider cultural context in which infant-feeding choices are made and alter components that make it difficult for US women to feed their infants optimally.

Breast Feeding↗

PubMed2001

A survey of trainee obstetricians preferences for childbirth.

OBJECTIVE: To determine trainee obstetricians personal preferences regarding mode and place of delivery given various scenarios. STUDY DESIGN: An anonymous nationwide postal survey of 365 specialist registrars. RESULTS: The response rate was 76%. About 2.5% preferred a home birth. And 16% of men and 15% of women opted for elective cesarean section (CS). When faced with a proposed trial of instrumental delivery in theatre, 60% accepted and a further 12% accepted only if they could choose the obstetrician performing the delivery. Regarding a breech presentation at term, 78% would accept external cephalic version (ECV). CONCLUSIONS: The percentage of obstetricians who preferred vaginal delivery and ECV were considerably higher than previously reported, and there were no significant gender differences. This study shows a more balanced attitude from obstetricians and refutes the previously held view that they necessarily advocate high levels of intervention for themselves.

Attitude of Health Personnel↗

PubMed2001

Dog exposure in infancy decreases the subsequent risk of frequent wheeze but not of atopy.

BACKGROUND: Influence of household pets in the development of childhood asthma or atopy has been controversial. OBJECTIVE: The purpose of this study was to investigate whether pet exposure in early life decreases the subsequent risk of frequent wheezing and/or allergic sensitization. METHODS: This was a prospective observational birth cohort study. The setting was a large health maintenance organization in Tucson, Ariz; the subjects were a population sample of 1246 newborns enrolled at birth and followed prospectively to age 13 years. The main outcome measures were as follows: time to first report of frequent wheezing (>3 episodes in the past year), skin prick test reactivity at 6 years and 11 years of age, and total serum IgE at 9 months, 6 years, and 11 years of age. RESULTS: Children living in households with > or =1 indoor dogs at birth were less likely to develop frequent wheeze than those not having indoor dogs (P =.004). This inverse association was confined to children without parental asthma (hazard ratio = 0.47; P <.001 [Cox regression]) and was not evident for children with parental asthma (hazard ratio = 0.96; P =.87). Adjustment by potential confounders did not change the results. Indoor cat exposure was not significantly associated with the risk of frequent wheezing. Neither cat exposure in early life nor dog exposure in early life was associated with skin prick test reactivity or total serum IgE at any age. CONCLUSION: Dog exposure in early life might prevent the development of asthma-like symptoms, at least in low-risk children with no family history of asthma. Nevertheless, early pet exposure does not seem to significantly influence the development of allergic sensitization.

Adolescent↗

PubMed2001

Factors influencing the relation of infant feeding to asthma and recurrent wheeze in childhood.

BACKGROUND: The relationship between infant feeding and childhood asthma is controversial. This study tested the hypothesis that the relation between breast feeding and childhood asthma is altered by the presence of maternal asthma. METHODS: Healthy non-selected newborn infants (n = 1246) were enrolled at birth. Asthma was defined as a physician diagnosis of asthma plus asthma symptoms reported on > or = 2 questionnaires at 6, 9, 11 or 13 years. Recurrent wheeze (> or = 4 episodes in the past year) was reported by questionnaire at seven ages in the first 13 years of life. Duration of exclusive breast feeding was based on prospective physician reports or parental questionnaires completed at 18 months. Atopy was assessed by skin test responses at the age of 6 years. RESULTS: The relationship between breast feeding, asthma, and wheeze differed with the presence or absence of maternal asthma and atopy in the child. After adjusting for confounders, children with asthmatic mothers were significantly more likely to have asthma if they had been exclusively breast fed (OR 8.7, 95% CI 3.4 to 22.2). This relationship was only evident for atopic children and persisted after adjusting for confounders. In contrast, the relation between recurrent wheeze and breast feeding was age dependent. In the first 2 years of life exclusive breast feeding was associated with significantly lower rates of recurrent wheeze (OR 0.45, 95% CI 0.2 to 0.9), regardless of the presence or absence of maternal asthma or atopy in the child. Beginning at the age of 6 years, exclusive breast feeding was unrelated to prevalence of recurrent wheeze, except for children with asthmatic mothers in whom it was associated with a higher odds ratio for wheeze (OR 5.7, 95% CI 2.3 to 14.1), especially if the child was atopic. CONCLUSION: The relationship between breast feeding and asthma or recurrent wheeze varies with the age of the child and the presence or absence of maternal asthma and atopy in the child. While associated with protection against recurrent wheeze early in life, breast feeding is associated with an increased risk of asthma and recurrent wheeze beginning at the age of 6 years, but only for atopic children with asthmatic mothers.

Adolescent↗

PubMed2001

Increased incidence of asthmalike symptoms in girls who become overweight or obese during the school years.

The possibility of a causal relationship is suggested by recent concomitant increases in the prevalence of obesity and asthma. In a general population sample, prevalence and incidence of asthma symptoms, skin tests, and body mass index (BMI) were ascertained at mean ages of 6.3 (n = 688) and 10.9 (n = 600) yr. Lung function, bronchodilator responsiveness, and daily peak flow variability were measured at 11 yr of age. There was no association between BMI at age 6 and wheezing prevalence at any age. Females, but not males, who were overweight or obese at 11 yr of age were more likely to have current wheezing at ages 11 and 13 but not at ages 6 or 8. This effect was strongest among females beginning puberty before the age of 11. Females who became overweight or obese between 6 and 11 yr of age were 7 times more likely to develop new asthma symptoms at age 11 or 13 (p = 0.0002); at age 11 their peak flow variability and bronchodilator responsiveness were significantly more likely to be increased. In females, becoming overweight or obese between 6 and 11 yr of age increases the risk of developing new asthma symptoms and increased bronchial responsiveness during the early adolescent period.

Age Distribution↗

PubMed2001

Relation of two different subtypes of croup before age three to wheezing, atopy, and pulmonary function during childhood: a prospective study.

OBJECTIVE: Some retrospective evidence suggests that children with a history of croup may be at increased risk of subsequently developing asthma, atopy, and diminished pulmonary function. The objective of this study was to determine the long-term outcome of croup (as diagnosed by a physician) in early life. METHODS: Lower respiratory illnesses (LRIs) in the first 3 years of life were assessed in 884 children who were enrolled in a large longitudinal study of airway diseases at birth. Pulmonary function tests, markers of atopy, and wheezing episodes were studied at different ages between birth and 13 years. RESULTS: Ten percent of children had croup with wheeze (Croup/Wheeze), 5% had croup without wheeze (Croup/No Wheeze), 36% had another LRI (Other LRI), and 48% had no LRI. Respiratory syncytial virus was more frequently isolated in children with Croup/Wheeze and Other LRI than in those with Croup/No Wheeze. There was no association between croup in early life and markers of atopy measured during the school years. Only children with Croup/Wheeze and with Other LRI had a significant risk of subsequent persistent wheeze later in life. Significantly lower levels of indices of intrapulmonary airway function were observed at ages <1 (before any LRI), 6, and 11 years in children with Croup/Wheeze and Other LRI compared with children with No LRI. Conversely, inspiratory resistance before any LRI episode was significantly higher in infants who later developed Croup/No Wheeze than in the other 3 groups. CONCLUSIONS: We distinguish 2 manifestations of croup with and without wheezing. Children who present with croup may or may not be at increased risk of subsequent recurrent lower airway obstruction, depending on the initial lower airway involvement, and preillness and postillness abnormalities in lung function associated with this condition.

Asthma↗

PubMed2001

Navajo perceptions of asthma and asthma medications: clinical implications.

BACKGROUND: Despite the large number of asthma patients, relatively little is known about the beliefs of asthmatic children and their parent(s), or the extent to which these beliefs influence management of the disease. OBJECTIVE: The purpose of this study was to examine how medication-taking and the use of health care services were influenced by perceptions of the disease and beliefs about medications among Navajo families. METHODS: Ethnographic interviews were used to investigate the disease and medication beliefs of 22 Navajo families with 29 asthmatic children. RESULTS: Most respondents perceived asthma as the transient experience of symptoms in someone who was chronically vulnerable to breathing problems. The majority (97%) of these asthmatics reported using bronchodilators, although only 34% reported current use of antiinflammatory medications. Although controller medications were distinguished from rescue medications, they were thought to have the same effect on the lungs. Many families were concerned about becoming dependent on the medicines and attempted to "wean" the asthmatic from the drugs. A large proportion (80%) of children had assumed responsibility for their own medication taking. Parents often referred to previous attacks requiring treatment in the emergency department when deciding whether to initiate medication or seek medical attention, often resulting in a delay of treatment. Nebulized treatments delivered in the emergency department were perceived to be the strongest therapy available. As a result, visits to the emergency department were common (79%), as were hospital admissions (57%). CONCLUSION: This study provides evidence that, among pediatric Navajo asthma patients, perceptions of asthma and beliefs about the activity of asthma medications influence when and how often asthma medicines are taken, as well as the use of health care services. In addition, excessive reliance on emergency treatments and the high rates of hospital admissions suggest that asthma is undertreated in this group of Navajo patients.

Adolescent↗

PubMed2001

Relation between infantile colic and asthma/atopy: a prospective study in an unselected population.

OBJECTIVE: To assess whether children with history of infantile colic may be at increased risk of subsequently developing asthma and/or atopy. METHODS: We used data collected in a large, prospective study from an unselected population. Infantile colic and concurrent feeding method were determined from the 2-month well-infant visit form completed by the physician for 983 children who were enrolled at birth. Markers of atopy (total serum immunoglobulin E and allergy skin prick test), allergic rhinitis, asthma, wheezing, and peak flow variability were the main outcome measures studied at different ages between infancy and 11 years. RESULTS: Ninety (9.2%) children had infantile colic. Prevalence of colic was similar among children fed either breast milk or formula. There was no association between infantile colic and markers of atopy, asthma, allergic rhinitis, wheezing, or peak flow variability at any age. CONCLUSION: Our data cannot support the hypothesis that infantile colic provides increased risk for subsequent allergic disease or atopy.

Asthma↗

PubMed2000

Siblings, day-care attendance, and the risk of asthma and wheezing during childhood.

BACKGROUND: Young children with older siblings and those who attend day care are at increased risk for infections, which in turn may protect against the development of allergic diseases, including asthma. However, the results of studies examining the relation between exposure to other children and the subsequent development of asthma have been conflicting. METHODS: In a study involving 1035 children followed since birth as part of the Tucson Children's Respiratory Study, we determined the incidence of asthma (defined as at least one episode of asthma diagnosed by a physician when the child was 6 to 13 years old) and the prevalence of frequent wheezing (more than three wheezing episodes during the preceding year) in relation to the number of siblings at home and in relation to attendance at day care during infancy. RESULTS: The presence of one or more older siblings at home protected against the development of asthma (adjusted relative risk for each additional older sibling, 0.8; 95 percent confidence interval, 0.7 to 1.0; P=0.04), as did attendance at day care during the first six months of life (adjusted relative risk, 0.4; 95 percent confidence interval, 0.2 to 1.0; P=0.04). Children with more exposure to other children at home or at day care were more likely to have frequent wheezing at the age of 2 years than children with little or no exposure (adjusted relative risk, 1.4; 95 percent confidence interval, 1.1 to 1.8; P=0.01) but were less likely to have frequent wheezing from the age of 6 (adjusted relative risk, 0.8; 95 percent confidence interval, 0.6 to 1.0; P=0.03) through the age of 13 (adjusted relative risk, 0.3; 95 percent confidence interval, 0.2 to 0.5; P<0.001). CONCLUSIONS: Exposure of young children to older children at home or to other children at day care protects against the development of asthma and frequent wheezing later in childhood.

Adolescent↗

PubMed2000

Prostate cancer and other xenografts from cells in peripheral blood of patients.

Good models for the investigation of human prostate cancer are few. Cells from approximately 9.2-21 ml of peripheral blood from patients with metastatic prostate cancer or metastatic colon cancer were injected s.c. into nude mice. Prostate cancer from 2 of 11 patients and colon cancer from 1 of 3 patients were found to be growing as metastases in the lungs of the nude mice. To our knowledge, this is the first report of the formation of xenografts from carcinoma cells taken directly from the peripheral blood of patients. Expanding circulating cancer cells with this approach may have important translational applications including: (a) development of models of human cancers; and (b) sampling of cancers from specific patients for novel molecular and therapeutic approaches.

Animals↗

PubMed2000

Maternal asthma status alters relation of infant feeding to asthma in childhood.

The relation of infant feeding to childhood asthma is controversial. This study tested the hypothesis that maternal asthma alters the relation of breastfeeding to childhood asthma. Questionnaires were completed at age 6, 9 or 11 years by parents of 1043 children enrolled at birth. Active MD asthma was defined as a physician diagnosis of asthma plus asthma symptoms reported on one of the questionnaires. Duration of exclusive breastfeeding, categorized as never, < 4 months, or > or = 4 months, was based on prospective physician reports or questionnaires completed at 18 months. The relationship between breastfeeding and asthma differed by maternal asthma status. For children with maternal asthma, the percent developing active MD asthma increased significantly with longer duration of exclusive breastfeeding. Odds of developing asthma among these children were significantly elevated (OR: 5.7,CI: 2.8-11.5), after adjusting for confounders. This association of longer exclusive breastfeeding with increased risk of reported asthma among children with asthmatic mothers may be biologically based, or may reflect reporting biases.

Asthma↗