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1.
Phys Rev Lett ; 128(13): 132002, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35426724

RESUMEN

The first measurement of lepton-jet momentum imbalance and azimuthal correlation in lepton-proton scattering at high momentum transfer is presented. These data, taken with the H1 detector at HERA, are corrected for detector effects using an unbinned machine learning algorithm (multifold), which considers eight observables simultaneously in this first application. The unfolded cross sections are compared with calculations performed within the context of collinear or transverse-momentum-dependent factorization in quantum chromodynamics as well as Monte Carlo event generators.

2.
Eur Phys J C Part Fields ; 77(11): 791, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-31997933

RESUMEN

The strong coupling constant α s is determined from inclusive jet and dijet cross sections in neutral-current deep-inelastic ep scattering (DIS) measured at HERA by the H1 collaboration using next-to-next-to-leading order (NNLO) QCD predictions. The dependence of the NNLO predictions and of the resulting value of α s ( m Z ) at the Z-boson mass m Z are studied as a function of the choice of the renormalisation and factorisation scales. Using inclusive jet and dijet data together, the strong coupling constant is determined to be α s ( m Z ) = 0.1157 ( 20 ) exp ( 29 ) th . Complementary, α s ( m Z ) is determined together with parton distribution functions of the proton (PDFs) from jet and inclusive DIS data measured by the H1 experiment. The value α s ( m Z ) = 0.1142 ( 28 ) tot obtained is consistent with the determination from jet data alone. The impact of the jet data on the PDFs is studied. The running of the strong coupling is tested at different values of the renormalisation scale and the results are found to be in agreement with expectations.

3.
Epidemiol Psychiatr Sci ; 24(3): 258-65, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24636750

RESUMEN

AIMS: To explore the role of psychiatric admission, diagnosis and reported unfair treatment in the relationship between ethnicity and mistrust of mental health services. METHODS: The Mental Illness-Related Investigations on Discrimination (MIRIAD) study was a cross-sectional study of 202 individuals using secondary mental health services in South London. Two structural equation models were estimated, one using Admission (whether admitted to hospital for psychiatric treatment in the past 5 years) and one using involuntary admission to hospital in the past 5 years. RESULTS: Increased mistrust was directly associated with the latent variable 'unfair treatment by mental health services and staff' and with Black or mixed ethnicity in both models. Those with a diagnosis of schizophrenia spectrum (as compared to depression and bipolar disorder) had a lower average score on the latent variable, suggesting that on average they reported less unfair treatment. We found evidence of increased reporting of unfair treatment by those who had an admission in the past 5 years, had experienced involuntary admission, and for people of Black of mixed Black and White ethnicity. CONCLUSIONS: Neither prevalence of schizophrenia spectrum nor rates of hospital admission explained the greater mistrust of mental health services found among people of Black and mixed Black and White ethnicity compared with White ethnicity. Rather, people of Black and mixed Black and white ethnicity may be more likely to experience unfair treatment, generating mistrust; furthermore, this group is more likely to express mistrust even after accounting for reporting of unfair treatment by mental health services and staff.

4.
Soc Psychiatry Psychiatr Epidemiol ; 49(10): 1599-608, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25038739

RESUMEN

PURPOSE: Research suggests levels of discrimination among mental health service users in England are high, but fell over the course of the first phase of the Time to Change programme to reduce stigma and discrimination (2008-2011). The aim of this study was to determine changes in discrimination levels, both overall and by the area of life in which discrimination is experienced, since Time to Change began and over the first year of its second phase (2011-2012). METHOD: Separate samples of mental health service users were interviewed annually from 2008 to 2012 using the Discrimination and Stigma Scale. In 2011 and 2012, social capital was also measured using the Resource Generator-UK. RESULTS: Sample percentages of participants reporting the experience of discrimination in one or more life areas for years 2008-2012 were 91.4, 86.5, 86.2, 87.9 and 91.0 %, respectively. A multivariable logistic regression model was performed to test for significant differences by study year, weighted to match the study population and adjusted for employment status and diagnosis as potential confounding factors. The odds of reporting discrimination in one or more life areas were significantly lower as compared to 2008 for all subsequent years except for 2012 (0.76, 95 % CI 0.49-1.19). However, a weighted multiple regression model provided evidence of decreased mean overall discrimination in 2012 as compared to 2008 (mean decrease -7.57, 95 % CI -11.1 to -4.0, p < 0.001). The weighted mean number of social resources was 13.5 in 2012 as compared to 14.0 in 2011 (mean difference -0.60, 95 % CI -1.25 to 0.06). CONCLUSIONS: While the overall level of discrimination across the life areas studied has fallen over 2008-2012, there is no evidence that more people using mental health services experience no discrimination. We suggest that the pattern suggesting a recent rise in discrimination following an earlier reduction may be linked to economic austerity. Further, the welfare benefits system has become an increasing source of discriminatory experience.


Asunto(s)
Trastornos Mentales/psicología , Servicios de Salud Mental , Prejuicio , Estigma Social , Adulto , Inglaterra , Femenino , Humanos , Entrevistas como Asunto , Masculino , Trastornos Mentales/terapia , Servicios de Salud Mental/estadística & datos numéricos , Persona de Mediana Edad , Capital Social , Encuestas y Cuestionarios
6.
J Clin Densitom ; 4(4): 325-35, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11748337

RESUMEN

Many children have contractures and/or deformities that preclude positioning in a fully supine position. The purpose of this study was to evaluate the effects of "poor" positioning on the assessment of body composition with dual X-ray absorptiometry (DXA) in thirty-seven normal child volunteers ages 3-16 yr. Multiple whole-body DXA scans of each child were performed: duplicate scans in the correct fully supine position, two scans while simulating different positions typical of children with contractures, and a scan while positioned in the full lateral position as a "worst-case" scenario. Also evaluated were the precision of duplicate measures in the altered positions, the effect of knee flexion contractures, and the impact of metallic orthopedic fixation devices. Errors in body composition assessment did occur from "poor" positioning. In those positions simulating children with contractures, the mean errors were 4-6% for measures of bone mineral content, 1-3% for lean body mass, and 5-11% for fat mass. Measures in the correct fully supine position and the contracted positions were highly correlated. The errors obtained by altering position were small. If errors of this magnitude are of significance, then corrective equations could be utilized to improve accuracy. Precise and reasonably accurate measures of body composition can be obtained with DXA in children with disabilities and deformities that preclude fully supine positioning.


Asunto(s)
Absorciometría de Fotón , Composición Corporal , Postura , Adolescente , Niño , Preescolar , Contractura/fisiopatología , Niños con Discapacidad , Femenino , Humanos , Masculino , Prótesis e Implantes , Posición Supina
7.
Dev Med Child Neurol ; 43(6): 364-70, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11409824

RESUMEN

The aim of the study was to evaluate the health of children with cerebral palsy (CP) using a global assessment of quality of life, condition-specific measures, and assessments of health care use. A multicenter population-based cross-sectional survey of 235 children, aged 2 to 18 years, with moderate to severe impairment, was carried out using Gross Motor Function Classification System (GMFCS) levels III (n = 56), IV (n = 55), and V (n = 122). This study group scored significantly below the mean on the Child Health Questionnaire (CHQ) for Pain, General Health, Physical Functioning, and Impact on Parents. These children used more medications than children without CP from a national sample. Fifty-nine children used feeding tubes. Children in GMFCS level V who used a feeding tube had the lowest estimate of mental age, required the most health care resources, used the most medications, had the most respiratory problems, and had the lowest Global Health scores. Children with the most severe motor disability who have feeding tubes are an especially frail group who require numerous health-related resources and treatments. Also, there is a relationship among measures of health status such as the CHQ, functional abilities, use of resources, and mental age, but each appears to measure different aspects of health and well-being and should be used in combination to reflect children's overall health status.


Asunto(s)
Actividades Cotidianas , Parálisis Cerebral/clasificación , Protección a la Infancia , Personas con Discapacidad/clasificación , Indicadores de Salud , Estado de Salud , Calidad de Vida , Índice de Severidad de la Enfermedad , Adolescente , Parálisis Cerebral/complicaciones , Parálisis Cerebral/fisiopatología , Parálisis Cerebral/psicología , Niño , Preescolar , Estudios Transversales , Personas con Discapacidad/psicología , Femenino , Servicios de Salud/estadística & datos numéricos , Encuestas Epidemiológicas , Humanos , Masculino , América del Norte , Vigilancia de la Población , Desempeño Psicomotor , Encuestas y Cuestionarios
8.
Arthropod Struct Dev ; 30(1): 1-14, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18088940

RESUMEN

Male scale insects (Hemiptera: Coccoidea) undergo a metamorphosis of the neometabola type, from scale-like nymph through prepupa and pupa to winged adult. The nymphal instar before prepupa secretes a waxy protective covering that remains in place throughout metamorphosis and these covers are characteristic of each family of scale insects. Most scale insect families (e.g. mealybugs, eriococcids, diaspidids) have rather loosely woven male covers, but male nymphs in the family Coccidae (soft scales) construct more rigid, glassy wax tests, which need a special mechanism for adult emergence. In the New Zealand male soft scales, a suture across the posterior quarter of the test enables the back plate to flex at a pair of hinges, to be raised up off the substrate, and so allow egress. The waxy back plate hinges are secreted by groups of tubular ducts on the abdominal dorsum of 2nd-instar males, during construction of the test. Scanning electron micrographs (SEMs) show the detail and diversity of hinge types. The wax tests of most New Zealand Coccidae, both female and male, are apparently unique in that they are constructed in rows of hexagonal plates, separated by sutures, however in the male test, the sutures are all fused except for the back plate suture. The two species in the endemic New Zealand genus Pounamococcus have male tests more like those of species in the Australian genus Austrolecanium.

9.
Bone ; 26(1): 95-8, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10617162

RESUMEN

The purpose of this prospective study was to extend the results of previous studies to determine if an accelerated rate of loss of bone mineral density (BMD) continues for 6 years after a hip fracture. Eighty-five elderly patients who had sustained a hip fracture had determinations of BMD made at the time of fracture; 55 of these patients were available for reassessment of BMD 1 year later, and 21 were available for reassessment of BMD 6 to 7 years later. The change in BMD from injury to 1 year and from 1 to 6 years was determined and correlated with pre- and postinjury variables, such as ambulatory ability, dietary intake of calcium, serum vitamin D levels, and mental status. There was a marked decrease in BMD in the in the first year after fracture, with the mean change in BMD being -4.3% at the femoral neck and -1.8% at the lumbar spine. Between 1 and 6 years after fracture, however, there was a dramatic increase in the BMD at both the femoral neck and lumbar spine measurement sites. Relative to 1 year after fracture, the mean increases were 7.7% at the femoral neck and 4.5% at the lumbar spine. In many cases, the loss of bone mineral that occurred in the first year after fracture was completely recouped in the subsequent 5 years. Five of the 21 patients (24%) sustained a contralateral hip fracture in the 6 years after the index fracture. Lumbar spine BMD was lower at baseline (p = 0.112), 1 year after fracture (p = 0.007), and 6 years after fracture (p = 0.003) in patients who sustained a second hip fracture than in those who did not. There was a general decrease in the functional activity level of patients in the 6 years after a hip fracture, but there were no statistically significant relationships between changes in BMD and the functional mobility of patients. The mean calcium intake in patients improved remarkably in the 6 years after fracture, but there was no correlation between daily calcium intake and changes in BMD. During the first year after a hip fracture, there is a rapid loss of bone mineral from the lumbar spine and contralateral femoral neck. Between 1 and 6 years after fracture, however, BMD is likely to increase, perhaps to levels greater than those at baseline. Although this investigation is small, the findings of this study point to the importance of further larger studies to further clarify the natural history of BMD after a hip fracture and the potential impact of pharmacological intervention on that natural history.


Asunto(s)
Densidad Ósea , Fracturas de Cadera/patología , Anciano , Calcio/administración & dosificación , Calcio/sangre , Femenino , Humanos , Estudios Longitudinales , Masculino , Estudios Prospectivos , Vitamina D/sangre
10.
J Pediatr Orthop ; 20(1): 71-4, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10641693

RESUMEN

The relationships between bone density, mobility, and fractures were assessed in 41 boys with Duchenne muscular dystrophy. Bone density in the lumbar spine was only slightly decreased while the boys were ambulatory (mean z-score, -0.8), but significantly decreased with loss of ambulation (mean z-score, -1.7). In contrast, bone density in the proximal femur was profoundly diminished even when gait was minimally affected (mean z-score, -1.6), and then progressively decreased to nearly 4 standard deviations below age-matched normals (mean z-score, -3.9). These are consistent with the findings that 18 (44%) of the boys sustained a fracture, 66% of these fractures involved the lower extremities, and there were no spinal compression fractures. Furthermore, four (44%) of nine boys who were walking with aids or support at the time of fracture never resumed walking after the fracture. Osteoporosis is most profound in the lower extremities of boys with Duchenne muscular dystrophy, and begins to develop early while still ambulating. Frequent fractures that may result in loss of ambulation are the clinical consequences.


Asunto(s)
Densidad Ósea , Fracturas Espontáneas/etiología , Distrofia Muscular de Duchenne/complicaciones , Adolescente , Niño , Fracturas Espontáneas/epidemiología , Humanos , Masculino
11.
Pediatr Pulmonol ; 27(2): 80-4, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10088930

RESUMEN

With dual energy X-ray absorptiometry (DEXA), it is possible to quantitate important aspects of growth in children with cystic fibrosis (CF), supplementing the usual measures of height and weight. Of particular concern during growth is the accumulation of bone mineral, since osteoporosis and fractures are well-recognized problems in end-stage disease. Various measures of growth and body composition were examined in 40 children and young adults (ages 5.7-20.3 years, mean 11.9 years) and compared to age-, gender-, and race-matched normal controls. The mean (+/- SE) weight Z-score of the 40 CF patients was -0.70 +/- 0.11, and the mean height Z-score was -0.66 +/- 0.15. Relative to their matched normal controls, the CF patients had a deficit in total body bone mineral averaging 19.1% +/- 3.0%. The deficits in total body bone mineral correlated with pulmonary and nutritional measures of disease severity. Serum vitamin D levels, calcium intake, age, gender, use of steroids, and CF genotype were not found to be significant factors. In this group of children and young adults with CF, height and weight measures of growth were not dramatically reduced (mean Z-scores = -0.7), yet large deficits in total body bone mineral averaging nearly 20% were identified.


Asunto(s)
Composición Corporal , Densidad Ósea , Fibrosis Quística/fisiopatología , Absorciometría de Fotón , Adolescente , Estatura , Peso Corporal , Niño , Estudios Transversales , Femenino , Humanos , Masculino
12.
J Pediatr Hematol Oncol ; 20(4): 322-6, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9703005

RESUMEN

PURPOSE: Some children who survive a childhood malignancy have diminished bone mineral density (BMD). The purpose of this study is to assess when, and perhaps why, this problem develops. PATIENTS AND METHODS: BMD was longitudinally monitored in 37 children for a minimum of 1 year (mean, 23.4 months; range, 12 to 41 months) during and, in some cases, after chemotherapy. Evaluations included serum analyses (vitamin D, calcium, and alkaline phosphatase), assessment of calcium intake, and measures of growth and nutrition (height, weight, and skinfolds). RESULTS: BMD was already diminished at the start of treatment in some patients; 6 of 13 patients (46%) had a BMD z score in the hip or spine of < -1.0. However, only 1 patient (8%) was < -2.0. Most patients did not have a significant drop in BMD z scores during chemotherapy, but one in four did decrease at least 0.5 standard deviations. Age greater than 10 years, a drop in height z score, and treatment with cranial irradiation correlated with a drop in BMD z scores during treatment. In the year immediately after completion of chemotherapy, no consistent "catch-up" was observed in BMD z scores. CONCLUSIONS: In some patients, BMD z scores are diminished at the time of diagnosis and a drop may occur during treatment in others. Multiple factors related to the disease process and treatment likely contribute to these observations. Cranial irradiation, perhaps by impacting on growth hormone homeostasis, is one such factor. Fortunately, most survivors of a childhood malignancy will not have large deficits in BMD later in life.


Asunto(s)
Antineoplásicos/farmacología , Densidad Ósea/efectos de los fármacos , Neoplasias/complicaciones , Osteoporosis/etiología , Adolescente , Fosfatasa Alcalina/sangre , Calcifediol/sangre , Calcitriol/sangre , Calcio/sangre , Niño , Preescolar , Irradiación Craneana/efectos adversos , Femenino , Trastornos del Crecimiento/etiología , Humanos , Estudios Longitudinales , Masculino , Proteínas de Neoplasias/sangre , Neoplasias/sangre , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Trastornos Nutricionales/complicaciones , Osteoporosis/sangre , Osteoporosis/inducido químicamente , Fósforo/sangre , Estudios Prospectivos , Traumatismos por Radiación/complicaciones
13.
Pediatr Radiol ; 28(4): 241-6, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9545479

RESUMEN

BACKGROUND: Children with cerebral palsy (CP), often nonambulatory and/or on anticonvulsants, are at increased risk for fractures. Bone mineral density (BMD) measured by the conventional techniques of dual-energy X-ray absorptiometry (DXA) often cannot be reliably or easily measured in these patients. OBJECTIVE: To find an alternative site to whole body, spine and hip that can be conveniently used to measure BMD in CP patients. MATERIALS AND METHODS: Having observed that CP patients prefer to lie on their sides, we explored measuring BMD at the distal femur in the lateral projection. A total of 92 scans were performed without sedation in 34 children and adolescents with CP, aged 4-19 years. Four femoral shaft subregions were created: two trabecular and two cortical. RESULTS: The coefficients of variation (CV %) were generally higher for opposite-side comparisons (n = 12 patients) than for same-side comparisons (n = 16 patients). For intra- and interobserver analyses, CV % were higher for cortical regions than for trabecular regions. Overall, the CV % were similar to those for hip and spine. CONCLUSION: This peripheral site in the femur should be considered as an alternative for patients with CP when whole-body, hip and spine DXA are not practical.


Asunto(s)
Absorciometría de Fotón/métodos , Densidad Ósea , Parálisis Cerebral/diagnóstico por imagen , Fémur/diagnóstico por imagen , Adolescente , Adulto , Niño , Preescolar , Humanos , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados
14.
J Child Neurol ; 12(7): 443-7, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9373801

RESUMEN

Calcitriol (1,25-dihydroxy vitamin D) is an important hormone in calcium and phosphate metabolism. Levels of calcitriol and its precursor, 25-hydroxy vitamin D (calcidiol), were measured in a heterogeneous group of 125 noninstitutionalized children and adolescents with spastic cerebral palsy. Levels of each were correlated with: (1) clinical factors including mobility, prior fracture, and use of anticonvulsants; (2) nutrition and growth parameters including skinfolds, body mass index, and use of vitamin supplements; and (3) other serum analyses including osteocalcin as a marker of bone formation, calcium, and alkaline phosphatase. Levels of calcidiol and calcitriol did not correlate with any of the various clinical, nutritional, or growth parameters examined. The prevalence of low (< 10 ng/mL) levels of calcidiol was significant (19%), and dependent on the season of the year in which the level was measured. In contrast, less than 2% of the patients were found to have a low (< 20 pg/mL) level of calcitriol and the mean was comparable to normal pediatric subjects. Levels of calcitriol are maintained in noninstitutionalized children with cerebral palsy despite anticonvulsants, poor nutrition, and calcidiol levels that vary greatly with the seasons.


Asunto(s)
Calcifediol/sangre , Calcitriol/sangre , Parálisis Cerebral/sangre , Adolescente , Anticonvulsivantes , Constitución Corporal , Calcifediol/análisis , Calcitriol/análisis , Parálisis Cerebral/fisiopatología , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Masculino , Estado Nutricional , Estaciones del Año
15.
Skeletal Radiol ; 26(9): 544-7, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9342815

RESUMEN

OBJECTIVE: To assess the correlation between a pediatric patient's proximal femur and lumbar spine bone mineral density (BMD) Z-scores, and the side-to-side difference between proximal femurs. DESIGN: Three hundred and thirty-nine patients aged 2.2-17.0 years with an assortment of underlying conditions underwent dual-energy X-ray absorptiometry (DXA) measures of BMD in both proximal femurs and the lumbar spine. RESULTS: Z-scores in the proximal femur and lumbar spine correlated highly (r = 0.73, P = 0.0001), but for individual patients the difference was often significant, and increased as BMD deviated further from normal. For patients with proximal femur Z-scores of 1 to -1 the mean difference between proximal femur and lumbar spine Z-scores was 0.5; with proximal femur Z-scores of less than -3 the mean difference was increased to 1.7. In conditions which symmetrically involve the lower extremities, the right and left proximal femur Z-scores differed on average by only 0.2. CONCLUSION: BMD measurements for pediatric patients are most easily interpreted by clinicians if converted to Z-scores, yet these are usually available only for the lumbar spine. Age-normalized BMD assessment at more than one site is necessary to provide a more reliable, complete assessment of bone mineral status in pediatric patients.


Asunto(s)
Absorciometría de Fotón , Densidad Ósea , Fémur/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Adolescente , Niño , Preescolar , Humanos , Osteoporosis/diagnóstico por imagen , Análisis de Regresión
16.
Bone ; 21(1): 79-82, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9213011

RESUMEN

The purpose of this prospective study was to monitor the bone mineral density (BMD) of the lumbar spine and contralateral femoral neck in the first year following an osteoporosis-related fracture of the hip. Eighty-three elderly patients (mean age 77 years) who had sustained a hip fracture had determinations of BMD made at the time of fracture; 49 of these patients were available for reassessment of BMD 1 year later. The change in BMD was correlated with pre- and postinjury variables, such as ambulatory ability, dietary intake of calcium, serum vitamin D levels, mental status, and routine serologies. The mean decrease in BMD in the year following fracture was 5.4% from the contralateral femoral neck and 2.4% from the lumbar spine. Calcium intake correlated with the loss of BMD from the femoral neck (p = 0.015), but not the lumbar spine. Patients with daily calcium intakes of less than 500 mg/day had a more than 10% decrease in femoral neck BMD in the year following their hip fracture. Serum 1,25-dihydroxy vitamin D level correlated with loss of MBD from the lumbar spine (p = 0.001), but not from the femoral neck. There was no correlation between the loss of bone mineral from either measurement site and age, sex, level of ambulation, or mental status. The loss of BMD from the femoral neck in the year following a hip fracture is more than five times that reported in the nonfractured population. This accelerated rate of loss can have drastic consequences in an elderly population already exhibiting osteopenia and propensity to fall. Investigation of pharmacologic or other interventions in the first critical year following a hip fracture may potentially blunt this accelerated rate of bone loss and lessen the risk of subsequent fractures.


Asunto(s)
Densidad Ósea/fisiología , Fracturas de Cadera/fisiopatología , Osteoporosis/fisiopatología , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Calcio de la Dieta/uso terapéutico , Femenino , Cuello Femoral/fisiología , Estudios de Seguimiento , Fracturas de Cadera/patología , Fracturas de Cadera/rehabilitación , Humanos , Estudios Longitudinales , Vértebras Lumbares/fisiología , Masculino , Salud Mental , Persona de Mediana Edad , Estado Nutricional , Osteoporosis/dietoterapia , Estudios Prospectivos , Vitamina D/análogos & derivados , Vitamina D/sangre
17.
J Paediatr Child Health ; 33(3): 209-12, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9259294

RESUMEN

OBJECTIVE: This study was made to: (i) identify the prevalence of low calcium intakes in a paediatric population with loosely defined 'milk allergy'; and (ii) assess long-term (mean 21 months later) changes in calcium intake following a single nutrition counselling session with those patients initially found to have a low intake. METHODOLOGY: Calcium intake was assessed in a cross-sectional study of 58 patients ages 5-16 years (mean 9.9 years) with IgG radioallergosorbent test (RAST) class II or higher for cow's milk protein. Those 31 patients found to have a low calcium intake were prospectively re-evaluated 12-30 months later following a single nutrition counselling session. RESULTS: Calcium intake was < recommended dietary allowance (RDA) for 31 of 58 (53%) patients. The patient's perception of their intake was unreliable; 44% of those who rated their calcium intake fair or good did not meet their RDA. Taking a calcium supplement did not ensure adequate intake; 21% of those taking supplements still did not meet their RDA. Milk intake predicted calcium intake; 8% of those who did not drink milk vs 68% of those who did drink at least some milk met their RDA without supplementation. The 31 patients with low intakes received counselling and were re-evaluated at an average follow-up of nearly 2 years. Calcium intake was increased a mean of 360 mg/day and use of supplements increased from 10 to 52% of the group. Despite these positive changes, 48% still did not meet their RDA. CONCLUSION: Limited milk intake is likely to be associated with suboptimal calcium intake. Efforts should be made to educate the family about the importance of calcium and its non-dairy sources. With many families repeated discussions of this issue may be necessary to influence calcium intake.


Asunto(s)
Calcio de la Dieta/administración & dosificación , Fenómenos Fisiológicos Nutricionales Infantiles , Inmunoglobulina G/análisis , Hipersensibilidad a la Leche/dietoterapia , Leche/inmunología , Adolescente , Animales , Calcio de la Dieta/uso terapéutico , Bovinos , Niño , Preescolar , Consejo , Estudios Transversales , Humanos , Leche/efectos adversos , Hipersensibilidad a la Leche/inmunología , Hipersensibilidad a la Leche/metabolismo , Estudios Prospectivos , Prueba de Radioalergoadsorción
18.
Dev Med Child Neurol ; 39(4): 224-7, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9183259

RESUMEN

Forty-three patients with spastic quadriplegia (mean age 7.9 years, range 3.3 to 17.2 years) underwent bone mineral density (BMD) measurement of the lumbar spine and were evaluated between 2.6 and 5.5 years (mean 3.8) later to determine whether this measurement had predicted risk of fracture over the subsequent period of observation. Other potential risk factors that were evaluated include body weight z score, serum vitamin D levels, previous fracture, and hip spica casting. The baseline measurements showed that BMD falls further below normal with increasing age and was more than one standard deviation below age-matched normal mean in 38 of the 43 patients. Fracture rate did not differ between those with low and those with very low spinal BMD. Similarly, serum vitamin D levels and body weight z scores were not predictive of fracture. However, fracture rate was over fourfold greater following spica casting and more than threefold greater following an initial fracture. Fracture rates in the study group were similar to those reported for age- and sex-matched normal children, though generally the location of the fractures and mechanisms of injury differed.


Asunto(s)
Densidad Ósea , Fracturas Óseas/etiología , Cuadriplejía/complicaciones , Cuadriplejía/diagnóstico por imagen , Absorciometría de Fotón , Adolescente , Factores de Edad , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Modelos Lineales , Vértebras Lumbares/diagnóstico por imagen , Masculino , Espasticidad Muscular , Valor Predictivo de las Pruebas , Cintigrafía , Factores de Riesgo
19.
South Med J ; 90(4): 378-83, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9114826

RESUMEN

Serum levels of the important hormone 1,25-dihydroxyvitamin D (1,25-diOHD, calcitriol) have not been extensively evaluated in patients with cystic fibrosis (CF) during the critical period of skeletal growth and development. This study was a cross-sectional, observational assessment of 25-hydroxyvitamin D (25-OHD, calcidiol) and 1,25-diOHD levels in 54 patients with CF. The patients' ages ranged from 4.9 years to 19.5 years (mean, 11.0 years). Levels were correlated with pulmonary function tests, chest x-ray scores, height and weight Z scores, skinfold percentiles, CF genotype, serum chemistries, and use of a vitamin supplement. Levels were compared with those in more than 160 other pediatric patients living in the same region, and all assays were done in the same laboratory. Despite low-normal levels of the 25-OHD precursor, there was a high prevalence of low (18%) and marginal (18%) levels of 1,25-diOHD. None of the various parameters examined correlated with either 25-OHD or 1,25-diOHD levels. The cause, clinical significance, and treatment of low levels of this important hormone in children with CF warrant further study.


Asunto(s)
Fibrosis Quística/sangre , Vitamina D/análogos & derivados , Adolescente , Adulto , Estatura , Peso Corporal , Niño , Estudios Transversales , Fibrosis Quística/diagnóstico por imagen , Fibrosis Quística/genética , Fibrosis Quística/fisiopatología , Alimentos Fortificados , Genotipo , Humanos , Pulmón/diagnóstico por imagen , Pulmón/fisiopatología , Radiografía , Pruebas de Función Respiratoria , Grosor de los Pliegues Cutáneos , Vitamina D/administración & dosificación , Vitamina D/sangre
20.
J Pediatr Hematol Oncol ; 18(4): 367-71, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8888743

RESUMEN

PURPOSE: The purpose of this study was to assess bone mineralization in survivors of childhood malignancies. PATIENTS AND METHODS: Bone mineral density (BMD) of the lumbar spine was measured in 60 patients aged 5.5-20.1 years (mean, 12.4 years) who had no known disease 1.0-14.5 years (mean, 4.3 years) after completing treatment for a malignancy. The age-normalized BMD findings (Z scores) were correlated with multiple variables, including measures of growth and nutrition, type of malignancy, and various treatments, including use of steroids, methotrexate, or cranial irradiation. RESULTS: BMD was normal in most patients with a mean Z score of -0.28 + 0.14 (+/- SE). Only 8% of the patients were more than 2 SDs below age-matched normal BMD. Weight Z score was the major determinant of BMD Z score. Calcium intake and height Z score were also important variables. CONCLUSIONS: Most survivors of childhood malignancies will not be left with a clinically significant deficit in BMD. Risk factors for diminished BMD include low-weight and low-height Z scores and low calcium intake. Therapeutic interventions are available to address these risk factors in those patients with significantly diminished BMD.


Asunto(s)
Antineoplásicos/efectos adversos , Densidad Ósea , Adolescente , Peso Corporal , Calcio/metabolismo , Niño , Preescolar , Estudios Transversales , Cabeza/efectos de la radiación , Humanos , Lactante , Neoplasias/terapia
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