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1.
BMC Cancer ; 22(1): 1202, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36418985

RESUMO

BACKGROUND: Weight gain is commonly observed during and after breast cancer treatment and is associated with poorer survival outcomes, particularly in women with oestrogen receptor-positive (ER +) disease. The aim of this study was to co-design (with patients) a programme of tailored, personalised support (intervention), including high-quality support materials, to help female breast cancer patients (BCPs) with ER + disease to develop the skills and confidence needed for sustainable weight loss.  METHODS: ER + BCPs were recruited from two UK National Health Service (NHS) Trusts. The selection criteria included (i) recent experience of breast cancer treatment (within 36 months of completing primary treatment); (ii) participation in a recent focus group study investigating weight management perceptions and experiences; (iii) willingness to share experiences and contribute to discussions on the support structures needed for sustainable dietary and physical activity behaviour change. Co-design workshops included presentations and interactive activities and were facilitated by an experienced co-design researcher (HH), assisted by other members of the research team (KP, SW and JS). RESULTS: Two groups of BCPs from the North of England (N = 4) and South Yorkshire (N = 5) participated in a two-stage co-design process. The stage 1 and stage 2 co-design workshops were held two weeks apart and took place between Jan-March 2019, with each workshop being approximately 2 h in duration. Guided by the Behaviour Change Wheel, a theoretically-informed weight management intervention was developed on the basis of co-designed strategies to overcome physical and emotional barriers to dietary and physical activity behaviour change. BCPs were instrumental in designing all key features of the intervention, in terms of Capability (e.g., evidence-based information, peer-support and shared experiences), Opportunity (e.g., flexible approach to weight management based on core principles) and Motivation (e.g., appropriate use of goal-setting and high-quality resources, including motivational factsheets) for behaviour change. CONCLUSION: This co-design approach enabled the development of a theoretically-informed intervention with a content, structure and delivery model that has the potential to address the weight management challenges faced by BCPs diagnosed with ER + disease. Future research is required to evaluate the effectiveness of the intervention for eliciting clinically-important and sustainable weight loss in this population.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Medicina Estatal , Redução de Peso , Dieta , Estrogênios
2.
J Dent Res ; 101(4): 384-391, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34757884

RESUMO

Dental procedures produce aerosols that may remain suspended and travel significant distances from the source. Dental aerosols and droplets contain oral microbes, and there is potential for infectious disease transmission and major disruption to dental services during infectious disease outbreaks. One method to control hazardous aerosols often used in industry is local exhaust ventilation (LEV). The aim of this study was to investigate the effect of LEV on aerosols and droplets produced during dental procedures. Experiments were conducted on dental mannequins in an 825.4-m3 open-plan clinic and a 49.3-m3 single surgery. Ten-minute crown preparations were performed with an air-turbine handpiece in the open-plan clinic and 10-min full-mouth ultrasonic scaling in the single surgery. Fluorescein was added to instrument irrigation reservoirs as a tracer. In both settings, optical particle counters (OPCs) were used to measure aerosol particles between 0.3 and 10.0 µm, and liquid cyclone air samplers were used to capture aerosolized fluorescein tracer. In addition, in the open-plan setting, fluorescein tracer was captured by passive settling onto filter papers in the environment. Tracer was quantified fluorometrically. An LEV device with high-efficiency particulate air filtration and a flow rate of 5,000 L/min was used. LEV reduced aerosol production from the air-turbine handpiece by 90% within 0.5 m, and this was 99% for the ultrasonic scaler. OPC particle counts were substantially reduced for both procedures and air-turbine settled droplet detection reduced by 95% within 0.5 m. The effect of LEV was substantially greater than suction alone for the air-turbine and was similar to the effect of suction for the ultrasonic scaler. LEV reduces aerosol and droplet contamination from dental procedures by at least 90% in the breathing zone of the operator, and it is therefore a valuable tool to reduce the dispersion of dental aerosols.


Assuntos
Raspagem Dentária , Aerossóis , Fluoresceína , Sucção
3.
Nat Commun ; 12(1): 56, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397922

RESUMO

RAC1 activity is critical for intestinal homeostasis, and is required for hyperproliferation driven by loss of the tumour suppressor gene Apc in the murine intestine. To avoid the impact of direct targeting upon homeostasis, we reasoned that indirect targeting of RAC1 via RAC-GEFs might be effective. Transcriptional profiling of Apc deficient intestinal tissue identified Vav3 and Tiam1 as key targets. Deletion of these indicated that while TIAM1 deficiency could suppress Apc-driven hyperproliferation, it had no impact upon tumourigenesis, while VAV3 deficiency had no effect. Intriguingly, deletion of either gene resulted in upregulation of Vav2, with subsequent targeting of all three (Vav2-/- Vav3-/- Tiam1-/-), profoundly suppressing hyperproliferation, tumourigenesis and RAC1 activity, without impacting normal homeostasis. Critically, the observed RAC-GEF dependency was negated by oncogenic KRAS mutation. Together, these data demonstrate that while targeting RAC-GEF molecules may have therapeutic impact at early stages, this benefit may be lost in late stage disease.


Assuntos
Carcinogênese/metabolismo , Carcinogênese/patologia , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Intestinos/patologia , Transdução de Sinais , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteína da Polipose Adenomatosa do Colo/metabolismo , Animais , Carcinogênese/genética , Homeostase , Intestinos/ultraestrutura , Camundongos Knockout , Mutação/genética , Especificidade de Órgãos , Fenótipo , Proteínas Proto-Oncogênicas c-vav/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T/metabolismo , Regulação para Cima , Via de Sinalização Wnt
4.
Science ; 164(3879): 568-9, 1969 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-5778009

RESUMO

Chromosome studies on human cells in vitro have shown that the artificial sweeteners, sodium and calcium cyclamate, can induce chromosome breaks in vitro in human cells, in both leukocyte and monolayer cultures.


Assuntos
Aberrações Cromossômicas , Cromossomos/efeitos dos fármacos , Leucócitos/citologia , Edulcorantes/farmacologia , Carcinoma , Técnicas de Cultura , Citogenética , Humanos , Neoplasias Laríngeas , Leucócitos/efeitos dos fármacos , Estimulação Química
5.
Science ; 235(4787): 460-5, 1987 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-17810340

RESUMO

Acid deposition and photochemical smog are urban air pollution problems, and they remain localized as long as the sulfur, nitrogen, and hydrocarbon pollutants are confined to the lower troposphere (below about 1-kilometer altitude) where they are short-lived. If, however, the contaminants are rapidly transported to the upper troposphere, then their atmospheric residence times grow and their range of influence expands dramatically. Although this vertical transport ameliorates some of the effects of acid rain by diluting atmospheric acids, it exacerbates global tropospheric ozone production by redistributing the necessary nitrogen catalysts. Results of recent computer simulations suggest that thunderstorms are one means of rapid vertical transport. To test this hypothesis, several research aircraft near a midwestern thunderstrom measured carbon monoxide, hydrocarbons, ozone, and reactive nitrogen compounds. Their concentrations were much greater in the outflow region of the storm, up to 11 kilometers in altitude, than in surrounding air. Trace gas measurements can thus be used to track the motion of air in and around a cloud. Thunderstorms may transform local air pollution problems into regional or global atmospheric chemistry problems.

6.
J Geophys Res Atmos ; 123(19): 11238-11261, 2018 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32023330

RESUMO

Deep convective transport of surface moisture and pollution from the planetary boundary layer to the upper troposphere and lower stratosphere affects the radiation budget and climate. This study uses cloud-parameterized Weather Research and Forecasting model coupled with Chemistry simulations to analyze the subgrid deep convective transport of CO at 12- and 36-km horizontal resolution in supercell and mesoscale convective systems observed during the 2012 Deep Convective Clouds and Chemistry field campaign and compares the simulation results with aircraft measurements and cloud-resolved simulations. The best Weather Research and Forecasting simulation of these storms was obtained with the use of the Grell-Freitas convective scheme. The default Weather Research and Forecasting model coupled with Chemistry subgrid convective transport scheme was replaced with a scheme to compute convective transport within the Grell-Freitas subgrid cumulus parameterization, which resulted in improved transport simulations. We examined the CO tendencies due to subgrid- and grid-scale convective transport. Results showed that the subgrid convective transport started earlier than the grid-scale convective transport. The subgrid-scale convective transport reached its maximum during the hour prior to the formation of the grid-scale constant-altitude detrainment layer. After that, both the subgrid- and grid-scale convective transport began to decrease. The subgrid-scale convective transport played a more significant role in the supercell case than the mesoscale convective system case. Subgrid contribution reached ~90% at the beginning of the storm and decreased to ~30% (17%) for the 36-km (12-km) domain 4 hr later.

7.
Endocrinology ; 137(7): 2774-81, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8770897

RESUMO

Insulin-like growth factors (IGFs) play an important role in tissue repair, including healing of dermal and epidermal injury. In this study we have measured changes in the IGF:IGF-binding protein (IGFBP) profile of rat wound fluid (WF) collected after sc implantation of Hunt-Schilling chambers for 21 days. WF IGF-I levels 1 day after implantation were equivalent to plasma levels, then fell during the first 7 days before recovering to approximately two thirds of plasma levels by day 21. Western ligand blots of whole WF revealed a profile qualitatively similar to that found in plasma, although the intensity of the IGFBP-3 band was significantly less than that in plasma. Neutral gel chromatography of pooled day 14 WF, after in vitro incubation with [125I]IGF-I, separated the radioligand into three distinct regions of 150, 40, and 7.5 kDa. However, compared to plasma recovery of[125I]IGF-I in the 150-kDa region in WF was reduced, and that in the 40-kDa region was increased. Ligand blotting of the WF-derived neutral gel fractions revealed IGFBP-3 within the 150-kDa complex. Incubation of WF with plasma (1:1, vol/vol) resulted in a progressive decline in the intensity of the plasma IGFBP-3 band. Protease inhibitors, including EDTA, antipain, or aprotonin, inhibited this process. We have described the changes over time in WF IGF-I concentrations, characterized the IGFBP profile, and demonstrated the presence of IGFBP-3 proteolytic activity in WF. The latter may play a role in the regulation of IGF bioavailability during the repair process.


Assuntos
Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Ferimentos e Lesões/fisiopatologia , Animais , Contagem de Eritrócitos , Exsudatos e Transudatos , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Fator de Crescimento Insulin-Like II/metabolismo , Radioisótopos do Iodo , Contagem de Leucócitos , Masculino , Contagem de Plaquetas , Ensaio Radioligante , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/metabolismo , Fatores de Tempo , Ferimentos e Lesões/sangue
8.
Am J Psychiatry ; 155(6): 818-23, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9619156

RESUMO

OBJECTIVE: The prevalence and etiology of pre- and postpartum depressive symptoms in women in a variety of family forms have been well documented, but relatively little research has been conducted on the adjustment of their male partners. The authors' goals in this study were 1) to estimate rates of depression during the pregnancy and 8 weeks following the birth of a child in a large representative community sample of fathers in different family structures and 2) to explore the role of stressful life events, social and emotional support, the quality of the partner relationship, and socioeconomic circumstances. METHOD: This study describes the relations of family setting and other correlates to men's depressive symptoms during the pregnancies (18 weeks gestation, on average) and 8 weeks after the births of children for 7,018 partners of female participants in the Avon Longitudinal Study of Pregnancy and Childhood. RESULTS: Men living in stepfamilies had-significantly higher levels of depressive symptoms before and after the birth than did men in more traditional families. The effect of stepfamily status on depression was mediated by education, life events, social support, social network, and level of aggression in the partnership. CONCLUSIONS: There are similarities in the patterns and correlates of depression after the birth of a child for men and women. These findings point to the importance of family and partnership ecology in the adjustment of men before and after the birth of a child.


Assuntos
Transtorno Depressivo/epidemiologia , Características da Família , Pai/psicologia , Poder Familiar/psicologia , Adulto , Agressão/psicologia , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Escolaridade , Pai/estatística & dados numéricos , Feminino , Humanos , Acontecimentos que Mudam a Vida , Masculino , Casamento/psicologia , Período Pós-Parto , Gravidez , Qualidade de Vida , Apoio Social
9.
J Am Acad Child Adolesc Psychiatry ; 38(6): 731-7, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10361792

RESUMO

OBJECTIVE: To determine the distribution of behavioral and emotional problems and competencies among a sample of Vietnamese children aged 4 through 18 years living in Hanoi. METHOD: A representative community sample of 1,526 children and adolescents was selected from 2 precincts in Hanoi. Problems and competencies were assessed with the Child Behavior Checklist (CBCL). RESULTS: Vietnamese children had lower mean raw scores than U.S. norms on the CBCL's Total, Externalizing, Internalizing, and Competence scales. Boys were reported to have more externalizing problems and girls more internalizing problems. Girls' levels of internalizing problems increased significantly with age. CONCLUSION: The lower levels of problems and competencies reported in Vietnamese children may represent differences in the prevalence of psychiatric disorders, in parental perceptions of what constitutes deviant behavior, or in parental comfort with reporting psychopathological behaviors. Further research is needed to clarify the relationship between the reported behavioral and emotional problems of Vietnamese children and the presence of psychiatric disorders. From a clinical perspective, the study's results suggest that levels of problems and competencies may vary significantly between different ethnic and cultural groups. Specific clinical cutoffs used to identify children requiring further psychiatric assessment need to be established separately for different ethnic groups.


Assuntos
Atitude Frente a Saúde/etnologia , Sintomas Comportamentais/epidemiologia , Transtornos Mentais/epidemiologia , Pais , Adolescente , Sintomas Comportamentais/psicologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Transtornos Mentais/psicologia , Pais/psicologia , Valores de Referência , Análise de Regressão , Estudos de Amostragem , Saúde da População Urbana/estatística & dados numéricos , Vietnã/epidemiologia
10.
Int J Gynaecol Obstet ; 37(4): 285-8, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1350545

RESUMO

A case of intravenous leiomyomatosis with massive ascites is reported. This is the first such recorded case. The patient was treated with a subtotal abdominal hysterectomy and bilateral salpingo-oophorectomy. Pathological examination established a vessel wall origin. There is no evidence of recurrence up to 20 months after initial treatment.


Assuntos
Ascite/cirurgia , Leiomioma/cirurgia , Útero/irrigação sanguínea , Feminino , Humanos , Histerectomia , Leiomioma/patologia , Pessoa de Meia-Idade , Doenças Vasculares/patologia , Doenças Vasculares/cirurgia , Veias
11.
Meat Sci ; 40(3): 319-26, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-22060023

RESUMO

This was a preliminary study to investigate whether hyaline cartilage could be easily identified in mechanically recovered meat (MRM) and whether its presence could be used as a possible marker for MRM in meat products. MRMs produced from beef, pork, lamb, chicken and turkey, using a variety of machine types and processing conditions, were compared to both minced and colloid milled hand-deboned samples, using a chemical staining technique followed by examination using the light microscope. The methodology was tested on various mixtures of MRM and hand-deboned meat. Although this technique, as with most microscopy techniques generally, is not suitable for quantitative determinations, the results indicate that light microscopy could be used as a useful screening method.

12.
Meat Sci ; 40(3): 327-36, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-22060024

RESUMO

The possibility of using immunological techniques as a method for the detection of mechanically recovered chicken meat in meat products has been investigated in this preliminary study. Antibodies were raised against a low molecular weight fraction (≤ 30 kDa) of chicken bone marrow proteins and an enzyme-linked immunosorbent assay (ELISA) developed. The system was used to test for the presence of mechanically recovered meat (MRM) in a range of product types, from raw chicken meat through to heat processed samples. The results show that it is possible to raise antibodies to chicken bone marrow proteins which show a strong reactivity with chicken and turkey MRM but show little reaction with extracts of MRM and hand deboned meat of other common meat species. However, blood, skin and soya all affected the accuracy of the ELISA. This study has demonstrated the potential for the use of an immunological procedure as a rapid test for MRM. The selectivity of the antiserum would, however, have to be increased before this procedure could be considered as a suitable technique for the detection of MRM in meat products.

13.
West Indian Med J ; 47(3): 113-4, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9861865

RESUMO

Tubo-ovarian abscess usually results from ascending infection of the lower genital tract. In a few cases it can occur as a result of direct contamination at the time of tubal sterilization. We describe a case that presented seven years after post partum tubal sterilization, showing both acute and chronic components.


PIP: This paper presents the case of a 32-year-old woman who developed a tubo-ovarian abscess 7 years following tubal ligation via minilaparotomy. Symptoms experienced included pain, which was exacerbated by walking, and mild deep dyspareunia. Abdominal and pelvic examinations revealed pain in the left iliac fossa, cervical excitation tenderness, and an ill-defined left adnexal mass. Sonographic evaluation of the pelvis showed an irregularly shaped, cystic mass (8.0 x 4.5 x 5.3 cm) with thickened internal septations and solid parts. A left tubo-ovarian multilobulated complex mass adherent to the omentum and the pelvic side was found upon laparotomy. There was pus in the Pouch of Douglas, and the uterus was 10 weeks in size with symmetrical enlargement. The previously ligated right fallopian tube and the ovary were unremarkable. Management includes left adnexectomy, omental biopsy, and 5-day course of antibiotics against Staphylococcus aureus, which was cultured from the purulent material in the Pouch of Douglas. Tubo-ovarian abscess should be considered in diagnosing patients presenting symptoms of pelvic inflammatory disease.


Assuntos
Abscesso/etiologia , Doenças Ovarianas/etiologia , Infecções Estafilocócicas/etiologia , Esterilização Tubária/efeitos adversos , Abscesso/diagnóstico , Adulto , Feminino , Humanos , Laparotomia , Doenças Ovarianas/diagnóstico , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus/isolamento & purificação
14.
West Indian Med J ; 53(1): 47-9, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15114895

RESUMO

This paper reports the case of a 21-year-old Afro-Caribbean pregnant woman with hyperthyroidism and hypokalaemic quadriparesis and reviews the literature on the topic. Thyrotoxic periodic paralysis is a very rare condition in the Caribbean. This case reminds West Indian physicians to consider this rare condition in any patient that presents with paralysis.


Assuntos
Hipopotassemia/etiologia , Paralisia/etiologia , Complicações na Gravidez/diagnóstico , Tireotoxicose/complicações , Adulto , Antitireóideos/uso terapêutico , População Negra , Carbimazol/uso terapêutico , Feminino , Humanos , Hipopotassemia/tratamento farmacológico , Potássio/uso terapêutico , Gravidez , Complicações na Gravidez/tratamento farmacológico , Tireotoxicose/diagnóstico , Tireotoxicose/tratamento farmacológico
15.
Environ Sci Technol ; 39(5): 1359-65, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15787378

RESUMO

The relative production rate of reactive oxygen in aqueous solution sensitized by fullerol (a polyhydroxylated, water-soluble form of the fullerene C60) was measured and compared to known reactive oxygen sensitizers using an oxygen consumption method. The solutions were irradiated by polychromatic visible and ultraviolet light. Reactive oxygen species were generated under both visible and ultraviolet light sources. The greatest rates of oxygen consumption were observed at acidic pH. We show for the first time evidence of both singlet oxygen and superoxide production by fullerol under both UV and polychromatic light sources.


Assuntos
Fulerenos/química , Nanoestruturas/química , Espécies Reativas de Oxigênio/análise , Concentração de Íons de Hidrogênio , Raios Ultravioleta , Água/química
16.
Nature ; 412(6848): 699-700, 2001 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-11507629

RESUMO

Spence speculates that Egypt's pyramid builders found true north by using a plumb line: when the stars Kochab and Mizar were seen on the same vertical, one was facing north. As evidence in support of this hypothesis, she points to the proposed interstar-line precession past the north celestial pole at a rate of 27' per century (cy). We argue that a mathematical error affects this result, which when corrected points more strongly to a different pair of stars. This suggests that the conventional ancient chronology, instead of being compressed, may actually have to be expanded slightly.

17.
J Child Psychol Psychiatry ; 40(7): 1025-37, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10576533

RESUMO

Links between sibling relationships, mother-partner, and parent-child relationships were studied in a longitudinal community sample of 3681 sibling pairs. Individual differences in sibling relationship quality were related to mother-partner affection and hostility assessed 4 years earlier, to contemporary parent-child negativity, and to indices of social adversity. Evidence for both direct and indirect pathways (via parent-child relations) linking mother-partner and sibling relations were found. Comparisons of prediction for non-stepfamilies and stepfather families showed similarities in patterns of association, but also differences: In stepfather families, mother-partner hostility was unrelated to parent-child negativity and sibling relationship quality. Both positivity and negativity towards young siblings decreased with the age of older siblings, and older sisters were more positive than older brothers.


Assuntos
Divórcio , Relações Familiares , Núcleo Familiar , Relações Pais-Filho , Adulto , Pré-Escolar , Feminino , Hostilidade , Humanos , Estudos Longitudinais , Masculino
18.
Br J Cancer ; 26(4): 315-20, 1972 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-4672286

RESUMO

Cell cultures derived from a mammary adenocarcinoma carried in inbred Fisher (CDF) strain female rats, have been shown to possess oncogenic activities and on injection into control rats to produce mammary carcinomata with a failure rate of only one out of 25 rats (i.e. 4%). Efforts have been made to alter the cultured cells, or to select populations from them, so that the response in rats to their antigenic characteristics might leave them with the ability to then reject injections of the active, untreated cancer cells. We have found that continuous treatment of the cultures by their own cell debris (sonicate), or by relatively high concentrations of intact, salmon-sperm DNA, lead to cell populations which have a decreased potential to produce mammary carcinomata, with a combined failure rate of 9 out of 12 rats (i.e. 75%): 5 out of these 12 rats (i.e. 41·7%) did not exhibit any growth (carcinomata or granulomata) after injection of these treated cells, and now all 5 (i.e. 100%) have the capacity to reject injections of the untreated, active cancer cells. Four of these rats (one died under anaesthesia) have now been found to also reject implants of the carcinoma itself.


Assuntos
Adenocarcinoma/imunologia , Neoplasias Mamárias Experimentais/imunologia , Animais , Antígenos de Neoplasias , Células Cultivadas/imunologia , DNA , Feminino , Cariotipagem , Masculino , Transplante de Neoplasias , Ratos , Ratos Endogâmicos , Salmonidae , Espermatozoides , Timo
19.
Br J Psychiatry ; 179: 110-5, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11483471

RESUMO

BACKGROUND: Children in stepfamilies and single-parent families exhibit elevated levels of behavioural and emotional problems compared with children in intact (biological) families, but there is variation within and across these family types. AIMS: To examine the sources of variation in children's behavioural and emotional problems across diverse family settings. METHOD: Levels of behavioural and emotional problems in children from diverse stepfamilies and single-parent families were compared with children living with both biological parents. Psychosocial risks were measured at the individual child and family levels. RESULTS: Behavioural and emotional problems were elevated in children in stepmother/complex stepfamilies and single-parent families, but not in simple stepfather families, relative to 'biological' families. Psychopathology associated with family type was explained by compromised quality of the parent-child relationship, parental depression and socio-economic adversity. Sibling similarity in behavioural and emotional problems was most pronounced in high-risk family settings. CONCLUSIONS: Family type is a proxy for exposure to psychosocial risks; the extent of family-wide influence on children's development may be strongest in high-stress settings.


Assuntos
Adaptação Psicológica , Sintomas Comportamentais/etiologia , Família/psicologia , Adolescente , Criança , Pré-Escolar , Interpretação Estatística de Dados , Características da Família , Humanos , Modelos Estatísticos , Relações Pais-Filho , Poder Familiar/psicologia , Escalas de Graduação Psiquiátrica , Fatores de Risco , Estresse Psicológico/etiologia
20.
Behav Genet ; 28(4): 243-53, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9803017

RESUMO

We propose and explore a twin model to examine the basis for synchrony that often characterizes different facets of normal development. In so doing we also present an approach to the analysis of "soft" events; events for which available reports of dates or ages of occurrence are unreliable or inconsistent. Discrepancies among reports are accounted for by a statistical measurement model. This combines current status error reflecting uncertain definition of onset and two mechanisms for the phenomenon of "telescoping," namely, systematic compression of the time scale and heteroscedastic random measurement error. Statistically, the model can be viewed as a mixed generalized linear model with random effects within both mean and variance functions or, alternatively, as involving multiplicative random effects. We apply the model to multiple maternal reports on menarche and onset of breast development in twin daughters. Fitted to data from the Virginia Twin Study Of Adolescent and Behavioral Development by the use of penalized/predictive quasi-likelihood, the model provided much improved estimates of the true age-at-onset distribution as compared to those from a naive analysis. Results suggested that the observed variance was made up almost entirely of genetic variance and measurement error variance due to telescoping and current status errors and that the timing of breast development and menarche are largely under the control of a common set of genes. Results also indicated that maternal recollections of the onset of breast development were both more poorly defined and subject to greater recall errors than maternal recollections of menarche.


Assuntos
Adolescente/fisiologia , Modelos Genéticos , Puberdade/genética , Idade de Início , Relógios Biológicos/genética , Mama/crescimento & desenvolvimento , Criança , Feminino , Humanos , Menarca/genética , Modelos Estatísticos , Estudos Retrospectivos , Gêmeos , Virginia/epidemiologia
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