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1.
Int J Obes (Lond) ; 38(1): 106-12, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23732657

RESUMO

OBJECTIVE: To compare portion size (PS) estimates, perceived energy density (ED) and anticipated consumption guilt (ACG) for healthier vs standard foods. METHODS: Three pairs of isoenergy dense (kJ per 100 g) foods-healthier vs standard cereals, drinks and coleslaws-were selected. For each food, subjects served an appropriate PS for themselves and estimated its ED. Subjects also rated their ACG about eating the food on a scale of 1 (not at all guilty) to 5 (very guilty). RESULTS: Subjects (n=186) estimated larger portions of the healthier coleslaw than that of the standard version, and perceived all healthier foods to be lower in ED than their standard alternatives, despite being isoenergy dense. Higher ACG was associated with the standard foods. Portion estimates were generally larger than recommendations and the ED of the foods was underestimated. CONCLUSIONS: The larger portions selected for the 'reduced fat' food in association with lower perceived ED and ACG suggests that such nutrition claims could be promoting inappropriate PS selection and consumption behaviour. Consumer education on appropriate portions is warranted to correct such misconceptions.


Assuntos
Comércio , Ingestão de Energia , Comportamento Alimentar/psicologia , Tamanho da Porção , Saúde Pública , Adulto , Comportamento do Consumidor , Comparação Transcultural , Europa (Continente) , Feminino , Indústria Alimentícia , Preferências Alimentares , Alimentos Fortificados , Alimentos Orgânicos , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Fenômenos Fisiológicos da Nutrição , Valor Nutritivo , Percepção , Tamanho da Porção/psicologia , Estados Unidos
2.
J Hum Nutr Diet ; 27(6): 617-25, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24303957

RESUMO

BACKGROUND: The present study aimed to compare the nutritional quality (NQ) and energy costs (EC) (£ MJ(-1) ) of own brand (OB) versus market brand (MB) foods in 2010 and 2012. METHODS: A list of processed foods (n = 32) was identified based on the most frequently consumed foods in the UK. Total fat, saturated fat, sugars, salt and energy density (ED) (kJ g(-1) ) in 2010 and 2012 were compared for six OB and one MB version of each food using a NQ scoring method based on the Food Standards Agency's Traffic Light System (TLS). Additional information (fruit, vegetable and nut content; protein; fibre and sodium) was recorded in 2012, and NQ was assessed using the Food Standards Agency's nutrient profiling model (NPM). The EC of the food baskets (FB) was compared in 2010 and 2012. RESULTS: There were no differences in overall NQ between OB and MB FB in 2010 (TLS, P = 0.978) or 2012 (TLS, P = 0.840; NPM, P = 0.696). However, the MB FB was highest in EC in 2010 and 2012 (both P < 0.001). There was an inverse relationship between the ED and EC of the MB foods in 2010 (r = -0.484; P = 0.005) and 2012 (r = -0.452; P = 0.009). CONCLUSIONS: The MB FB was higher in EC than the OB FB in 2010 and 2012 but not superior in overall NQ based on both the TLS and NPM.


Assuntos
Comércio , Ingestão de Energia , Fast Foods , Abastecimento de Alimentos , Valor Nutritivo , Fibras na Dieta , Fast Foods/economia , Fast Foods/normas , Abastecimento de Alimentos/economia , Abastecimento de Alimentos/normas , Humanos , Sódio na Dieta
3.
Proc Nutr Soc ; 71(4): 610-21, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22877767

RESUMO

Larger portion sizes (PS) may be inciting over-eating and contributing to obesity rates. Currently, there is a paucity of data on the effectiveness of serving size (SS) guidance. The aims of the present review are to evaluate SS guidance; the understanding, usability and acceptability of such guidance, its impact on consumers and potential barriers to its uptake. A sample of worldwide SS guidance schemes (n 87) were identified using targeted and untargeted searches, overall these were found to communicate various inconsistent and often conflicting messages about PS selection. The available data suggest that consumers have difficulty in understanding terms such as 'portion size' and 'serving size', as these tend to be used interchangeably. In addition, discrepancies between recommended SS and those present on food labels add to the confusion. Consumers generally understand and visualise SS best when expressed in terms of household measures rather than actual weights. Only a limited number of studies have examined the direct impact of SS guidance on consumer behaviour with equivocal results. Although consumers recognise that guidance on selecting SS would be helpful, they are often unwilling to act on such guidance. The challenge of achieving consumer adherence to SS guidance is formidable due to several barriers including chronic exposure to larger PS, distorted consumption norms and perceptions, the habit of 'cleaning one's plate' and language barriers for ethnic minorities. In conclusion, the impact of SS guidance on consumers merits further investigation to ensure that future guidance resonates with consumers by being more understandable, usable and acceptable.


Assuntos
Ingestão de Energia , Comportamento Alimentar , Rotulagem de Alimentos , Guias como Assunto , Comportamentos Relacionados com a Saúde , Obesidade/prevenção & controle , Meio Ambiente , Humanos , Cooperação do Paciente , Percepção
4.
Mucosal Immunol ; 2(1): 74-84, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19079336

RESUMO

Secretory immunoglobulin A (SIgA) is the most prevalent antibody in the human body and a first line of defense in mucosal immunity. We located secretory component (SC) relative to dimeric IgA1 (dIgA1) within the SIgA1 structure using the constrained modeling of solution scattering and analytical ultracentrifugation data. The extended solution structure of dIgA1 is largely preserved within SIgA1. From conformational searches of SC locations, the best-fit SC models within SIgA1 show that SC is extended along the outermost convex edge of the Fc dimer in dIgA1. The topology of our SIgA1 structure reveals that it is able to bind to one FcalphaRI receptor molecule. SC binding to the Fc dimer confers protection to SIgA1 by the masking of proteolytically susceptible surface sites from bacterial proteases in the harsh environment of the mucosa. The models support a "zipper-like" unfolding of SC upon dIgA1 in the formation and transportation of SIgA1 into the mucosa.


Assuntos
Imunoglobulina A/química , Imunoglobulina A/imunologia , Fragmentos Fc das Imunoglobulinas/química , Fragmentos Fc das Imunoglobulinas/imunologia , Multimerização Proteica , Componente Secretório/imunologia , Cristalografia por Raios X , Humanos , Imunidade nas Mucosas/imunologia , Modelos Moleculares , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína
5.
Child Maltreat ; 6(4): 300-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11675813

RESUMO

Research suggests that fathers' involvement in their children's lives is associated with enhanced child functioning. The current study examined (a) whether presence of a father was associated with better child functioning, (b) whether children's perceptions of fathers' support was associated with better functioning, and (c) whether the above association was moderated by the father's relationship to the child, the child's race, and the child's gender. Participants included 855 six-year-old children and their caregivers. Father presence was associated with better cognitive development and greater perceived competence by the children. For children with a father figure, those who described greater father support had a stronger sense of social competence and fewer depressive symptoms. The associations did not differ by child's gender, race, or relationship to the father figure. These findings support the value of fathers' presence and support to their children's functioning. Priorities for future research include clarifying what motivates fathers to be positively involved in their children's lives and finding strategies to achieve this.


Assuntos
Desenvolvimento Infantil , Relações Pai-Filho , Adulto , Criança , Transtornos do Comportamento Infantil/psicologia , Cognição , Estudos Transversais , Depressão/psicologia , Características da Família , Seguimentos , Humanos , Masculino , Projetos de Pesquisa , Autoimagem , Estados Unidos/epidemiologia
6.
Org Lett ; 3(21): 3325-7, 2001 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-11594825

RESUMO

[reaction: see text]. N-benzoylated quinone imine ketals undergo smooth cycloadditions in a [4 + 2] sense to yield the expected cycloadducts. The crude cycloadducts, when subjected to a short series of simple transformations, produce synthetically useful quantities of 5-methoxyindoles in excellent overall yields.


Assuntos
Indóis/síntese química , Aldeídos/química , Benzoquinonas/química , Química Farmacêutica , Iminas/química
7.
Org Lett ; 3(20): 3189-91, 2001 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-11574027

RESUMO

[reaction: see text] The total synthesis of the antibacterial and antimycotic alkaloid hapalindole Q has been achieved in eight steps and 12.4% overall yield. The key step involves a regio- and diastereoselective Diels-Alder reaction to afford a bicyclo[2.2.2]oct-2-ene. This cycloadduct was subsequently dihydroxylated, cleaved, and converted to the natural product.


Assuntos
Alcaloides/síntese química , Antibacterianos/síntese química , Indóis/síntese química , Cianobactérias/química
8.
J Infect Dis ; 184(7): 922-5, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11550129

RESUMO

The hormone human chorionic gonadotropin (hCG) serves to maintain the fetus during early pregnancy and regulate the onset of labor in late pregnancy. hCG also prevents Neisseria gonorrhoeae from developing invasive characteristics. Part of the beta subunit of hCG has an amino acid sequence similar to that of the hinge of human IgA1, which is the site of action of IgA1 proteases. This study examined the sensitivity of hCG to gonococcal IgA1 proteases, by means of autoradiography, immunoblotting, and RIA. hCG was cleaved in the beta subunit by the type 1 but not the type 2 IgA1 proteases of N. gonorrhoeae. hCG cleavage by gonococcal IgA1 proteases in vivo may increase the invasiveness of the pathogen and destroy its natural biologic activity, with major consequences for the fetus and the pregnancy.


Assuntos
Gonadotropina Coriônica/metabolismo , Neisseria gonorrhoeae/enzimologia , Serina Endopeptidases/metabolismo , Sequência de Aminoácidos , Autorradiografia , Gonadotropina Coriônica Humana Subunidade beta/química , Gonadotropina Coriônica Humana Subunidade beta/metabolismo , Humanos , Immunoblotting , Imunoglobulina A/química , Imunoglobulina A/metabolismo , Dados de Sequência Molecular , Fragmentos de Peptídeos/química
9.
Am J Hum Biol ; 13(2): 261-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11460872

RESUMO

Patterns of early postnatal growth were analyzed among low birthweight infants enrolled in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Infants were divided into four groups according to their neonatal status: (1) term, normal birthweight (NBW); (2) term, low birthweight (LBW); (3) moderately preterm LBW; and (4) very preterm LBW. Comparison of mean weight and length z-scores indicated that term NBW and very preterm LBW infants were at or near the national reference averages at 8, 12, and 18 months. Term LBW and moderately preterm infants were lighter and shorter than the other two study groups at each visit. Term LBW and moderately preterm infants displayed evidence of catch-up growth during the study period. Catch-up growth was defined as a decrease in the percentage of infants below the 10th percentile for weight. The effect of neonatal body proportions on postnatal growth was investigated in term LBW infants. The infants were divided into two groups based on their ponderal index (PI) at birth (low PI and proportionate PI). Comparison of weight and length z-scores indicated that both groups of term LBW infants improved in z-scores between birth and the first visit (approximately 8 months). However, infants with evidence of asymmetric intrauterine growth restriction (low PI) continued to improve in weight and length z-scores, whereas those with symmetric growth restriction (proportionate PI) remained lighter and shorter.


Assuntos
Recém-Nascido de Baixo Peso/crescimento & desenvolvimento , Seguridade Social , Peso ao Nascer , Retardo do Crescimento Fetal/complicações , Humanos , Lactente , Recém-Nascido
10.
J Org Chem ; 66(13): 4704-9, 2001 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-11421796

RESUMO

Indoles which bear an alkyl substituent in the 3-position undergo a [3 + 2] annulation reaction when treated with 1,1-cyclopropane diesters in the presence of Yb(OTf)(3) resulting in 2,3-cyclopentanoindolines. Typically, the reactions are performed at elevated temperatures or at ultrahigh pressures. In cases where steric crowding is an issue, ultrahigh pressures are required. In reactions involving substituted cyclopropanes, significant regio- and diastereocontrol was observed. When the substituent was aromatic or olefinic, the reactions took place at ambient temperature and pressure. The applicability of this methodology to the preparation of a key tetracyclic subunit of the kopsane alkaloids was demonstrated.


Assuntos
Alcaloides/síntese química , Alcanos/química , Ciclopentanos/síntese química , Alcaloides/química , Ciclopentanos/química , Ciclopropanos/química , Indóis/química
11.
Pediatrics ; 107(4): 728-35, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11335751

RESUMO

OBJECTIVES: There is mounting concern about how mothers' own victimization experiences affect their children. This study examines the effects of mothers' victimization on their own mental health and parenting and on their children's behavior, development, and health. The effects of both timing and type of victimization are assessed. A related objective was to determine if there was a cumulative risk effect produced by victimization during both childhood and adulthood, or both physical and sexual. SETTING: Urban families in an eastern state and urban and rural families in a southern state. PARTICIPANTS: A total of 419 mothers and their children 6 to 7 years old were identified from 2 sites. The eastern sample was recruited in the first 2 years of life from 3 pediatric clinics: 1 for children at high risk for human immunodeficiency virus disease, 1 for children with failure to thrive, and a third providing pediatric primary care. The southern sample was derived from a cohort of children at risk for adverse health or developmental outcomes, plus a systematic sampling of controls, recruited from area hospitals. At age 4, a random sample of children from the original cohort who had been maltreated along with a matched comparison group of nonmaltreated children were selected. RESULTS: In general, mothers victimized during both childhood and adulthood had poorer outcomes than mothers victimized during either childhood/adolescence or adulthood who in turn had worse outcomes than mothers with no history of victimization. This manifested as more maternal depressive symptoms, harsher parenting, and more externalizing and internalizing behavior problems in their children. There were no significant differences in maternal functioning or child outcomes between those abused in childhood and those abused in adulthood. These findings were similar for type of victimization. Mothers' depression and harsh parenting were directly associated with their children's internalizing and externalizing behavior problems. CONCLUSIONS: Maternal victimization appears to be a highly prevalent problem in high-risk samples and is associated with harmful implications for mental health and parenting, as well as for the offspring. Pediatricians need to consider past and current victimization of mothers. Routine screening for these problems, followed by appropriate evaluation and intervention may reduce maternal depression, improve parenting, and reduce the incidence of behavior problems in children.


Assuntos
Maus-Tratos Infantis/estatística & dados numéricos , Transtornos do Comportamento Infantil/epidemiologia , Filho de Pais com Deficiência/estatística & dados numéricos , Transtorno Depressivo/epidemiologia , Mães/estatística & dados numéricos , Violência/estatística & dados numéricos , Adulto , Fatores Etários , Criança , Maus-Tratos Infantis/psicologia , Abuso Sexual na Infância/psicologia , Abuso Sexual na Infância/estatística & dados numéricos , Transtornos do Comportamento Infantil/diagnóstico , Transtornos do Comportamento Infantil/etiologia , Filho de Pais com Deficiência/psicologia , Pré-Escolar , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/etiologia , Violência Doméstica/psicologia , Violência Doméstica/estatística & dados numéricos , Feminino , Humanos , Masculino , Mães/psicologia , Relações Pais-Filho , Poder Familiar/psicologia , Prevalência , Escalas de Graduação Psiquiátrica , Fatores de Risco , População Rural , Estados Unidos/epidemiologia , População Urbana , Violência/psicologia
13.
Org Lett ; 2(22): 3517-20, 2000 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-11082023

RESUMO

[reaction: see text] Ultrahigh pressures and catalytic Yb(OTf)(3).2H(2)O were found to mediate Diels-Alder reactions of various electron-deficient dienophiles with 1,3-cyclohexadiene to produce endo-bicyclo[2.2. 2]oct-2-enes in moderate to excellent yield and selectivity. The proposed total synthesis of hapalindole Q based on bicyclo[2.2. 2]oct-2-ene construction by Diels-Alder reaction and subsequent olefin cleavage is outlined. Preliminary results demonstrating the viability of this strategy are presented.


Assuntos
Alcaloides/síntese química , Compostos Bicíclicos com Pontes/química , Cicloexanos/química , Indóis/química , Alcaloides/química , Cicloexenos , Desenho de Fármacos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Pressão , Relação Estrutura-Atividade
14.
Biochem Biophys Res Commun ; 276(2): 749-55, 2000 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-11027542

RESUMO

Human neutrophil IgA receptors (FcalphaR) trigger phagocytosis of IgA-opsonized particles and activate the NADPH oxidase complex ultimately leading to pathogen destruction. Signal transduction events triggered by FcalphaR have not been investigated in the context of NADPH oxidase activation. In this study, we show that crosslinking FcalphaR triggers the release of Ca(2+) from an intracellular store that was unchanged by the addition of extracellular EGTA. This was in contrast to the thapsigargin-triggered Ca(2+) signal, which activates store-operated Ca(2+) entry pathways (SOCP) and is sensitive to extracellular EGTA. Buffering extracellular Ca(2+) with EGTA had no effect on FcalphaR-triggered NADPH oxidase activation, suggesting that SOCP was not required for activation by FcalphaR. EGTA inhibited thapsigargin-triggered NADPH oxidase activation but had no effect on PMA-triggered responses. The intracellular Ca(2+) chelator BAPTA caused dose-dependent inhibition of both FcalphaR-triggered and thapsigargin-triggered NADPH oxidase activation but had no effect on PMA-triggered responses. Our data demonstrate that FcalphaR-triggered NADPH oxidase activation is dependent on the release of Ca(2+) from an intracellular store, but is independent of SOCP.


Assuntos
Antígenos CD/fisiologia , Sinalização do Cálcio/fisiologia , Cálcio/metabolismo , NADPH Oxidases/metabolismo , Neutrófilos/enzimologia , Receptores Fc/fisiologia , Anticorpos Monoclonais , Sinalização do Cálcio/efeitos dos fármacos , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Humanos , Técnicas In Vitro , NADPH Oxidases/antagonistas & inibidores , Neutrófilos/metabolismo , Tapsigargina/farmacologia
15.
Cancer Causes Control ; 11(7): 635-43, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10977108

RESUMO

BACKGROUND: A case-control study was conducted with 183 histologically confirmed neuroblastoma cases aged 0-14 years diagnosed among residents of New York State, excluding New York City, between 1976 and 1987. Three hundred seventy-two controls were selected from the New York State live birth certificate registry and were matched to cases on year of birth. METHODS: Parental occupational exposures at the time of each child's birth were obtained from maternal telephone interviews, successfully completed for 85% of cases and 87% of controls. RESULTS: Odds ratios were significantly elevated for maternal occupation in the service (OR = 2.0, 95% CI = 1.0 4.1) and retail (OR = 2.0, 95% CI = 1.1-3.7) industries and paternal occupation in materials handling (OR = 3.8, 95% CI = 1.1-14.6). Odds ratios were also significantly elevated for maternal report of occupational exposure to acetone (OR = 3.1, 95% CI = 1.7-5.6), insecticides (OR = 2.3, 95% CI = 1.4-3.7), lead (OR = 4.7, 95% CI = 1.3-18.2) and petroleum (OR = 3.0, 95% CI = 1.5-6.1) and paternal exposure to creosote (OR = 2.1, 95% CI = 1.1-4.3), dioxin (OR = 6.9, 95% CI = 1.3-68.4), lead (OR = 2.4, 95% CI = 1.2-4.8), and petroleum (OR = 1.8, 95% CI = 1.1-2.8). CONCLUSIONS: Due to the uncertainty of the biologic plausibility of these associations and the possibility of alternative explanations, these results should be interpreted cautiously.


Assuntos
Neoplasias Encefálicas/etiologia , Exposição Materna/efeitos adversos , Neuroblastoma/etiologia , Exposição Ocupacional/efeitos adversos , Exposição Paterna/efeitos adversos , Acetona/efeitos adversos , Adolescente , Neoplasias Encefálicas/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Inseticidas/efeitos adversos , Masculino , Neuroblastoma/epidemiologia , Razão de Chances , Petróleo/efeitos adversos , Medição de Risco , Fatores de Risco , Estados Unidos/epidemiologia
16.
Immunol Lett ; 72(1): 1-6, 2000 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-10789674

RESUMO

NADPH oxidase assembly is considered to occur mainly on the plasma membrane and phagolysosome membranes and to a lesser extent in intracellular granules. Stimulation of neutrophils with phorbol 12-myristate 13-acetate (PMA) in conjunction with chemiluminescent substrates has been widely used as a model to understand the sub-cellular locations of NADPH-oxidase activity. Interpretation of data from such studies is complicated by observations that PMA does not trigger phagocytosis but results in formation of large macropinocytic vacuoles. Here we show by laser-scanning confocal microscopy that PMA triggers uptake of lucigenin into macropinocytic vacuoles and that no chemiluminescence (CL) can be detected at this location when NADPH oxidase assembly on the plasma membrane still occurs. This shows that the macropinocytic vacuole membrane is distinct from the phagocytic vacuole membrane although both compartments are derived from the plasma membrane.


Assuntos
NADPH Oxidases/metabolismo , Neutrófilos/enzimologia , Pinocitose , Acridinas/metabolismo , Membrana Celular/enzimologia , Humanos , Membranas Intracelulares/enzimologia , Medições Luminescentes , Microscopia Confocal , Microscopia Eletrônica , Ativação de Neutrófilo , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Explosão Respiratória , Acetato de Tetradecanoilforbol/farmacologia , Vacúolos/enzimologia
17.
Child Abuse Negl ; 24(5): 587-98, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10819092

RESUMO

OBJECTIVE: A cumulative risk model was used to examine the relationship among failure-to-thrive (FTT), maltreatment, and four aspects of children's development: cognitive performance (standardized testing), adaptive functioning at school, and classroom behavior (teacher report), and behavior at home (maternal report). METHOD: The sample included 193 6-year-old children and their families, recruited from pediatric clinics serving inner-city, low-income, primarily African-American families, who were part of a longitudinal investigation of child development and maltreatment. Four risk groups were formed based on their growth and maltreatment history: neither FTT nor Maltreatment, FTT Only, Maltreatment Only, and both FTT and Maltreatment. FTT was defined as a deceleration in weight gain (weight-for-age below the 5th percentile) prior to 25 months of age among children born at term with birth weight appropriate for gestational age. Maltreatment was defined as having at least one report to CPS for neglect, physical abuse and/or sexual abuse. RESULTS: Risk status was negatively associated with each of the four developmental outcomes. Children with a history of both FTT and maltreatment had more behavior problems and worse cognitive performance and school functioning than children with neither risk factor. Children with only one risk factor (either FTT or maltreatment) achieved intermediate scores. CONCLUSIONS: Findings support a cumulative risk model as being more detrimental to children's development than the presence of a single risk factor alone, consistent with theories linking the accumulation of environmental risks to negative consequences. These results underscore the importance of interventions to prevent both FTT and maltreatment during children's early years.


Assuntos
Negro ou Afro-Americano/psicologia , Maus-Tratos Infantis/psicologia , Transtornos do Comportamento Infantil/psicologia , Deficiências do Desenvolvimento/psicologia , Insuficiência de Crescimento/psicologia , Pobreza/psicologia , População Urbana , Criança , Feminino , Humanos , Deficiências da Aprendizagem/psicologia , Estudos Longitudinais , Masculino , Determinação da Personalidade , Fatores de Risco
18.
Arch Pediatr Adolesc Med ; 154(2): 135-41, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10665599

RESUMO

OBJECTIVE: To examine the association between father involvement and child neglect. DESIGN: Cohort study. SETTING: Participants were recruited from an inner-city pediatric primary care clinic and a clinic for children at risk for human immunodeficiency virus infection in a teaching hospital. PARTICIPANTS: Mothers and fathers or father figures, and 244 five-year olds participating in a longitudinal study. MAIN OUTCOME MEASURES: Child neglect measured via home observation, a videotaped mother-child interaction, and child protective services reports. RESULTS: A father or father figure was identified for 72% of the children. Rates of neglect ranged between 11% and 30%. Father absence alone was not associated with neglect. However, in families with an identified and interviewed father, a longer duration of involvement (P<.01), a greater sense of parenting efficacy (P<.01), more involvement with household tasks (P<.05), and less involvement with child care (P<.05) were associated with less neglect. The overall model explained 26.5% of the variance in neglect. CONCLUSIONS: There is substantial involvement of fathers in a subset of this high-risk sample, although more than a quarter of the children lacked a father or father figure. The mere presence of a father did not significantly influence the neglect of the children; rather, the nature of his involvement did. Fathers who felt more effective as parents were less likely to have neglected their children. A greater sense of efficacy may reflect parenting skills and be important in enhancing the contribution of fathers to their children's well-being. Pediatric health care providers can play a valuable role in enhancing the involvement and skills of fathers.


Assuntos
Maus-Tratos Infantis , Relações Pai-Filho , Pré-Escolar , Estudos de Coortes , Pai , Feminino , Humanos , Estudos Longitudinais , Masculino , Relações Mãe-Filho , Mães , Fatores Socioeconômicos
19.
J Infect ; 38(2): 99-106, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10342649

RESUMO

OBJECTIVES: patients with rheumatoid arthritis (RA) are reported to have in their sera raised levels of antibody specific to Proteus mirabilis. The aim of the study was to verify this and to determine an explanation for it by investigating the frequency of P. mirabilis urinary tract infection in RA patients and matched controls. METHODS: freshly voided urine was examined for the presence, number and identity of infecting bacteria. The levels of antibody in blood and in urine of the IgM, IgA and IgG classes to the common O serotypes of P. mirabilis and the antigens to which they reacted were determined by enzyme-linked immunosorbent assay (ELISA) and immunoblotting. RESULTS: analysis of urine from 76 patients with RA and 48 age- and gender-matched healthy controls showed that only two (4%) of the control urines but 25 (33%) of those from the RA patients were infected. The commonest infecting organism in the RA patients' urine was Proteus mirabilis which occurred twice as frequently as Escherichia coli. Proteus mirabilis was found in 52% of the infected urines of the RA patients and was always detected as a pure growth and usually in insignificant (< 10(4)/ml) numbers. It is highly improbable that this finding was the outcome of differences in age, physical ability or medication between the RA and control patient groups. Comparison of antibody levels to P. mirabilis by ELISA showed RA patients had raised (P < 0.0001, P = 0.001, P = 0.0063) levels of IgA, IgG and IgM respectively in their sera and raised (P < 0.0001, P < 0.0001, P = 0.0001) levels of IgG, IgM and IgA respectively in their urine compared with the control group. It was not possible to detect an antibody reacting to a P. mirabilis antigen that was specific to the RA patients. CONCLUSION: the results confirm that RA patients have raised levels of antibody to P. mirabilis not only in blood but also in urine and suggest that this arises because RA patients have an asymptomatic, non-significant P. mirabilis bacteriuria more frequently or more prolonged than control patients. This may be the trigger for their RA condition.


Assuntos
Artrite Reumatoide/complicações , Bacteriúria/complicações , Infecções por Proteus/complicações , Proteus mirabilis/isolamento & purificação , Infecções Urinárias/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/urina , Artrite Reumatoide/microbiologia , Western Blotting , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Testes de Fixação do Látex , Masculino , Pessoa de Meia-Idade , Infecções por Proteus/imunologia , Proteus mirabilis/imunologia , Fator Reumatoide/sangue , Infecções Urinárias/imunologia , Urina/microbiologia
20.
J Mol Biol ; 286(5): 1421-47, 1999 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-10064707

RESUMO

Human immunoglobulin A (IgA) is an abundant antibody that mediates immune protection at mucosal surfaces as well as in plasma. The IgA1 isotype contains two four-domain Fab fragments and a four-domain Fc fragment analogous to that in immunoglobulin G (IgG), linked by a glycosylated hinge region made up of 23 amino acid residues from each of the heavy chains. IgA1 also has two 18 residue tailpieces at the C terminus of each heavy chain in the Fc fragment. X-ray scattering using H2O buffers and neutron scattering using 100 % 2H2O buffers were performed on monomeric IgA1 and a recombinant IgA1 that lacks the tailpiece (PTerm455). The radii of gyration RG from Guinier analyses were similar at 6.11-6.20 nm for IgA1 and 5.84-6.16 nm for PTerm455, and their cross-sectional radii of gyration RXS were also similar. The similarity of the RG and RXS values suggests that the tailpiece of IgA1 is not extended outwards in solution. The IgA1 RG values are higher than those for IgG, and the distance distribution function P(r) showed two distinct peaks, whereas a single peak was observed for IgG. Both results show that the hinge of IgA1 results in an extended Fab and Fc arrangement that is different from that in IgG. Automated curve-fit searches constrained by homology models for the Fab and Fc fragments were used to model the experimental IgA1 scattering curves. A translational search to optimise the relative arrangement of the Fab and Fc fragments held in a fixed orientation resembling that in IgG was not successful in fitting the scattering data. A new molecular dynamics curve-fit search method generated IgA1 hinge structures to which the Fab and Fc fragments could be connected in any orientation. A search based on these identified a limited family of IgA1 structures that gave good curve fits to the experimental data. These contained extended hinges of length about 7 nm that positioned the Fab-to-Fab centre-to-centre separation 17 nm apart while keeping the corresponding Fab-to-Fc separation at 9 nm. The resulting extended T-shaped IgA1 structures are distinct from IgG structures previously determined by scattering and crystallography which have Fab-to-Fab and Fab-to-Fc centre-to-centre separations of 7-9 nm and 6-8 nm, respectively. It was concluded that the IgA1 hinge is structurally distinct from that in IgG, and this results in a markedly different antibody structure that may account for a unique immune role of monomeric IgA1 in plasma and mucosa.


Assuntos
Imunoglobulina A/química , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fc das Imunoglobulinas/química , Modelos Moleculares , Sequência de Aminoácidos , Animais , Bovinos , Simulação por Computador , Cristalização , Dissulfetos/química , Dissulfetos/metabolismo , Humanos , Imunoglobulina A/genética , Imunoglobulina G/química , Cadeias Pesadas de Imunoglobulinas/química , Camundongos , Dados de Sequência Molecular , Nêutrons , Estrutura Secundária de Proteína , Espalhamento de Radiação , Deleção de Sequência , Homologia de Sequência de Aminoácidos , Difração de Raios X
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