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1.
Acta Physiol (Oxf) ; 217(3): 240-53, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27029505

RESUMO

AIM: The maternal environment during pregnancy and lactation plays a determining role in programming energy metabolism in offspring. Among a myriad of maternal factors, disruptions in the light/dark cycle during pregnancy can program glucose intolerance in offspring. Out-of-phase feeding has recently been reported to influence metabolism in adult humans and rodents; however, it is not known whether this environmental factor impacts offspring metabolism when applied during pregnancy and lactation. This study aims to determine whether maternal day-restricted feeding (DF) influences energy metabolism in offspring. METHODS: Pregnant and lactating Wistar rats were subjected to ad libitum (AL) or DF during pregnancy and lactation. The offspring born to the AL and DF dams were intra- and interfostered, which resulted in 4 group types. RESULTS: The male offspring born to and breastfed by the DF dams (DF/DF off) were glucose intolerant, but without parallel insulin resistance as adults. Experiments with isolated pancreatic islets demonstrated that the male DF/DF off rats had reduced insulin secretion with no parallel disruption in calcium handling. However, this reduction in insulin secretion was accompanied by increased miRNA-29a and miRNA34a expression and decreased syntaxin 1a protein levels. CONCLUSION: We conclude that out-of-phase feeding during pregnancy and lactation can lead to glucose intolerance in male offspring, which is caused by a disruption in insulin secretion capacity. This metabolic programming is possibly caused by mechanisms dependent on miRNA modulation of syntaxin 1a.


Assuntos
Restrição Calórica/efeitos adversos , Insulina/metabolismo , Lactação/fisiologia , Prenhez/metabolismo , Animais , Cálcio/metabolismo , Metabolismo Energético/fisiologia , Feminino , Intolerância à Glucose/metabolismo , Técnicas In Vitro , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Masculino , MicroRNAs/biossíntese , MicroRNAs/genética , NADP/metabolismo , Gravidez , Ratos , Ratos Wistar , Sintaxina 1/biossíntese , Sintaxina 1/genética
2.
Br J Math Stat Psychol ; 54(Pt 1): 103-23, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11393895

RESUMO

Methods for the hierarchical clustering of an object set produce a sequence of nested partitions such that object classes within each successive partition are constructed from the union of object classes present at the previous level. Any such sequence of nested partitions can in turn be characterized by an ultrametric. An approach to generalizing an (ultrametric) representation is proposed in which the nested character of the partition sequence is relaxed and replaced by the weaker requirement that the classes within each partition contain objects consecutive with respect to a fixed ordering of the objects. A method for fitting such a structure to a given proximity matrix is discussed, along with several alternative strategies for graphical representation. Using this same ultrametric extension, additive tree representations can also be generalized by replacing the ultrametric component in the decomposition of an additive tree (into an ultrametric and a centroid metric). A common numerical illustration is developed and maintained throughout the paper.


Assuntos
Análise por Conglomerados , Modelos Estatísticos , Psicometria/métodos , Anticoncepção/classificação , Anticoncepção/estatística & dados numéricos , Árvores de Decisões , Feminino , Humanos , Masculino
3.
Methods Inf Med ; 40(5): 403-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11776739

RESUMO

OBJECTIVES: A new data-analysis strategy is proposed to solve the problems of selecting interaction terms in linear regression on the one hand, and of statistically testing the significance of regression trees on the other hand. METHODS: The proposed strategy combines two data mining techniques: regression trees and regression analysis with optimal scaling (CATREG). The method traces small regression trees using the bootstrap and integrates the results as interaction variables (called "trunk variables") into CATREG. RESULTS: An application to data from cardiac patients shows a relative increase of 19% variance accounted for (16% cross-validated variance), by the CATREG model including the trunk variables compared to the model excluding these variables. CONCLUSIONS: This study indicates that trunk variables can be useful to model interaction effects in prediction problems.


Assuntos
Sistemas de Apoio a Decisões Clínicas , Cardiopatias/prevenção & controle , Modelos Lineares , Inteligência Artificial , Simulação por Computador , Interpretação Estatística de Dados , Árvores de Decisões , Comportamentos Relacionados com a Saúde , Cardiopatias/psicologia , Humanos , Redes Neurais de Computação , Valor Preditivo dos Testes
4.
J Pediatr ; 137(4): 534-9, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11035834

RESUMO

OBJECTIVE: To determine the impact of preterm birth on health status (HS) development at the ages of 5 and 10 years in a cohort of children born before term. SAMPLE: Six hundred eighty-eight children, born in 1983 with a gestational age of <32 weeks and a birth weight of <1500 g. DESIGN: Prospectively collected HS variables, obtained from the parents, were analyzed in a longitudinal perspective by using principal component analyses. RESULTS: One third of the sample had minor to severe HS problems at both ages of measurement. One third had problems on one assessment only. The remainder of the sample had no HS problems at either age. The analyses grouped the HS variables into 3 combinations. Problems in basic functioning, such as mobility or speech, decreased with age. Negative moods substantially increased, and concentration problems increased slightly. Specifically at risk were preterm born children with handicaps, boys, and children who were small for gestational age. CONCLUSION: According to the parents, one third of the cohort had no HS problems at either age. The pattern of HS problems of the preterm born children changed between 5 and 10 years of age.


Assuntos
Nível de Saúde , Recém-Nascido Prematuro , Criança , Pré-Escolar , Estudos de Coortes , Pessoas com Deficiência , Feminino , Humanos , Recém-Nascido , Masculino , Estudos Prospectivos
5.
Health Psychol ; 18(5): 506-19, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10519467

RESUMO

In a meta-analysis of 37 studies, the effects of psychoeducational (health education and stress management) programs for coronary heart disease patients were examined. The results suggest that these programs yielded a 34% reduction in cardiac mortality; a 29% reduction in recurrence of myocardial infarction (MI); and significant (p < .025) positive effects on blood pressure, cholesterol, body weight, smoking behavior, physical exercise, and eating habits. No effects of psychoeducational programs were found in regard to coronary bypass surgery, anxiety, or depression. The results also suggest that cardiac rehabilitation programs that were successful on proximal targets (systolic blood pressure, smoking behavior, physical exercise, emotional distress) were more effective on distal targets (cardiac mortality and MI recurrences) than programs without success on proximal targets.


Assuntos
Adaptação Psicológica/fisiologia , Doença das Coronárias/prevenção & controle , Educação em Saúde , Estresse Psicológico/prevenção & controle , Estresse Psicológico/psicologia , Promoção da Saúde , Humanos
6.
Br J Psychiatry ; 170: 363-8, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9246256

RESUMO

BACKGROUND: Successive DSM versions struggle with the heterogeneity of the eating disorders. Criteria were mainly based on clinical impressions and on descriptive and inferential studies. METHOD: In a study of 55 eating-disordered adolescents, we investigated whether patients could be grouped on an empirical basis, using principal components analysis (PCA) with optimal scoring (scaling), i.e. PCA with no a priori assumptions. Clustering was based on Morgan-Russell subscales, each measured four times over the course of illness. RESULTS: Contrary to DSM-IV criteria, patients did not cluster primarily on the basis of anorectic symptoms; the occurrence of bulimic symptoms was more dominant. Core symptomatology (preoccupation with food, disturbed body perception and inadequate sexual behaviour) did not differ between patients, either at referral or over time. CONCLUSIONS: These results support the spectrum hypothesis of the eating disorders, which considers them as one syndrome with different manifestations.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos/classificação , Escalas de Graduação Psiquiátrica , Adolescente , Adulto , Anorexia Nervosa/classificação , Anorexia Nervosa/psicologia , Bulimia/classificação , Bulimia/psicologia , Criança , Progressão da Doença , Comportamento Alimentar , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Feminino , Humanos , Estudos Longitudinais , Estudos Prospectivos , Comportamento Sexual
7.
Biorheology ; 34(2): 127-38, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9373395

RESUMO

This paper deals with the mechanical characterization of brain tissue which behaves as a viscoelastic material. We focus on the linear viscoelastic behavior, which should apply for small strains at any strain rate, and demonstrate the applicability of the time/temperature superposition principle. This principle allows the opportunity to extend the range of shear rates for which the material is characterized, and makes the results applicable to impact conditions. This characterization of the linear behavior forms the basis for a further nonlinear characterization of the tissue.


Assuntos
Encéfalo/fisiologia , Estresse Mecânico , Animais , Bovinos , Elasticidade , Modelos Biológicos , Reologia , Temperatura , Fatores de Tempo , Viscosidade
8.
Diagn Cytopathol ; 17(6): 452-5, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9407207

RESUMO

The detection of diseases can exhibit seasonal fluctuations. This can be studied in cervical smears. Over a 9-year observation span (January 1983-January 1992) a series of 504,093 cervical smears obtained from a routine cytology laboratory in The Netherlands were examined for infections (monilia, trichomonas, actinomyces, human papilloma virus [HPV], chlamydia, and herpes) as well as for mild, moderate, and severe dysplasias, carcinoma in situ, and squamous carcinoma. Statistical analysis (principal component analysis) demonstrates clear seasonal rhythms in the detection of infections as well as in precursor lesions. These findings suggest that we are dealing with "true" detection rhythms. For the detection of (pre)malignancy and HPV, yearly fluctuations in women being screened might be the explanation for our observations.


Assuntos
Infecções/diagnóstico , Lesões Pré-Cancerosas/diagnóstico , Estações do Ano , Esfregaço Vaginal/estatística & dados numéricos , Actinomicose/diagnóstico , Actinomicose/epidemiologia , Candidíase/diagnóstico , Candidíase/epidemiologia , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia , Feminino , Humanos , Infecções/epidemiologia , Países Baixos/epidemiologia , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/epidemiologia , Tricomoníase/diagnóstico , Tricomoníase/epidemiologia , Infecções Tumorais por Vírus/diagnóstico , Infecções Tumorais por Vírus/epidemiologia , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/epidemiologia
9.
Anal Quant Cytol Histol ; 14(1): 60-72, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1558617

RESUMO

The purpose of this study was to investigate whether discrimination into five groups of various grades of cervical preneoplasia and neoplasia is possible using discriminant analysis models. Data were analyzed for 242 cases diagnosed as either slight dysplasia (n = 50), moderate dysplasia (n = 50), severe dysplasia (n = 50), carcinoma in situ (n = 50) or invasive carcinoma (n = 42) and consisted of qualitative and quantitative features of cells derived from a repeat sample taken from the ectocervix as well as the endocervix using Cytobrushes. The samples were embedded in plastic, and thin sections were prepared, resulting in a monolayer of cut nuclei. The percentages of expected correct prediction were obtained by using 10,000 double cross-validation samples; the mean percentage of correct prediction into five groups using cross-validation was 65% (in the original analysis, 72%) and into two groups (dysplasia versus carcinoma in situ and invasive carcinoma) was 91% (93%). The results reflect group discrimination potential; we do not claim reliability of prediction for an individual patient. The patients were not a representative sample of the population; to investigate whether groups of patients could be discriminated on the basis of both qualitative and quantitative features, the data analyzed contain an almost equal number of observations in each of the five groups. The results indicate that features do not classify the cases in the same way; the discriminant analyses suggest that quantitative features play an important role in the discrimination of dysplasia from carcinoma cases, while the majority of the qualitative features are important in discrimination within the three dysplasia groups.


Assuntos
Carcinoma in Situ/etiologia , Neoplasias do Colo do Útero/epidemiologia , Biópsia/métodos , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/patologia , Feminino , Humanos , Métodos , Plásticos , Valor Preditivo dos Testes , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/patologia
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