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1.
Int J Obes (Lond) ; 42(1): 115-118, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28871150

RESUMO

Intragastric Balloons are a temporary, reversible and safer option compared to bariatric surgery to promote significant weight loss, leading to improved metabolic outcomes. However, due to subsequent weight regain, alternative procedures are now preferred in adults. In adolescents, more amenable to lifestyle change, balloons may be an alternative to less reversible procedures. Our aim was to assess the tolerability and efficacy of the intragastric balloon in severely obese adolescents and the impact of associated weight loss on biomedical outcomes (glucose metabolism, blood pressure, lipid profiles) and bone density. A 2-year cohort study of 12 adolescents (BMI >3.5 s.d., Tanner stage >4) following 6 months intragastric balloon placement was carried out. Subjects underwent anthropometry, oral glucose tolerance test, and DEXA scans at 0, 6 and 24 months. The results showed clinically relevant improvements in blood pressure, insulin: glucose metabolism, liver function and sleep apnoea at 6 months. Changes were not sustained at 2 years though some parameters (Diastolic BP, HBA1c, insulin AUC) demonstrated longer-term improvement despite weight regain. Despite weight loss, bone mass accrual showed age appropriate increases. In conclusion, the intragastric balloon was safe, well tolerated and effective in supporting short-term weight loss and clinically relevant improvement in obesity-related complications, which resolved in some individuals. Benefits were not sustained in the majority at 2 years.


Assuntos
Balão Gástrico , Obesidade Mórbida , Adolescente , Pressão Sanguínea , Índice de Massa Corporal , Estudos de Viabilidade , Feminino , Humanos , Hipertensão/complicações , Masculino , Obesidade Mórbida/complicações , Obesidade Mórbida/fisiopatologia , Obesidade Mórbida/cirurgia , Resultado do Tratamento , Redução de Peso
2.
Int J Obes (Lond) ; 41(4): 591-597, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27795553

RESUMO

BACKGROUND: Severe adolescent obesity (body mass index (BMI) >99.6th centile) is a significant public health challenge. Current non-invasive treatments, including community-based lifestyle interventions, are often of limited effectiveness in this population, with NICE guidelines suggesting the use of bariatric surgery as the last line of treatment. Health professionals are understandably reluctant to commission bariatric surgery and as an alternative, the use of an intra-gastric balloon as an adjunct to a lifestyle programme might offer a reversible, potentially safer and less invasive option. OBJECTIVES: Explore the use of an intra-gastric balloon as an adjunct to a lifestyle support programme, to promote weight loss in severely obese adolescents. Outcomes included weight loss, waist and hip measurements, psychosocial outcomes including health-related quality of life (HRQoL) and physical self perceptions, physical activity and cardiorespiratory fitness. METHOD: Non-randomised pilot study. RESULTS: Twelve severely obese adolescents (5 males, 7 females; mean age 15 years; BMI >3.5 s.d.; puberty stage 4 or more) and their families were recruited. Mean weight loss at 12 months (n=9) was 3.05 kg±14.69; d=0.002, P=0.550, and a BMI Z-score (n=12) change of 0.2 s.d.; d=0.7, P=0.002 was observed at 6 months with a large effect, but was not sustained at 12 months (mean change 0.1 s.d.; d=0.3, P=0.146). At 24 months (n=10), there was a weight gain from baseline of +9.9 kg±1.21 (d=0.4; P=0.433). Adolescent and parent HRQoL scores exceeded the minimal clinical important difference between baseline and 12 months for all domains but showed some decline at 24 months. CONCLUSION: An intra-gastric balloon as an adjunct to a lifestyle support programme represents a safe and well-tolerated treatment approach in severely obese adolescents, with short-term effects on weight change. Improvements in psychosocial health, physical activity and cardiorespiratory fitness were maintained at 12 months, with varying results at 24 months.


Assuntos
Aptidão Cardiorrespiratória/fisiologia , Exercício Físico/fisiologia , Balão Gástrico , Obesidade Mórbida/terapia , Obesidade Infantil/terapia , Comportamento de Redução do Risco , Redução de Peso/fisiologia , Adolescente , Aptidão Cardiorrespiratória/psicologia , Inglaterra , Exercício Físico/psicologia , Feminino , Seguimentos , Humanos , Masculino , Obesidade Mórbida/epidemiologia , Obesidade Mórbida/fisiopatologia , Obesidade Mórbida/psicologia , Obesidade Infantil/epidemiologia , Obesidade Infantil/fisiopatologia , Obesidade Infantil/psicologia , Projetos Piloto , Qualidade de Vida , Fatores de Tempo , Resultado do Tratamento
3.
BMC Endocr Disord ; 17(1): 33, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28619024

RESUMO

BACKGROUND: Communication is complex in endocrine care, particularly during transition from paediatric to adult services. The aims of this study were to examine the feasibility of interventions to support young people to interact with clinicians. METHODS: Development and evaluation of a complex intervention in 2 phases: Pre-intervention observational study; Intervention feasibility study. Purposive sample of recordings of 62 consultations with 58 young people aged 11-25 years with long-term endocrine conditions in two paediatric and two adult endocrine clinics. Proportion of time talked during consultations, number and direction of questions asked; Paediatric Consultation Assessment Tool (PCAT); OPTION shared decision making tool; Medical Information Satisfaction Scale (MISS- 21). Young people were invited to use one or more of: a prompt sheet to help them influence consultation agendas and raise questions; a summary sheet to record key information; and the www.explain.me.uk website. RESULTS: Nearly two thirds of young people (63%) chose to use at least one communication intervention. Higher ratings for two PCAT items (95% CI 0.0 to 1.1 and 0.1 to 1.7) suggest interventions can support consultation skills. A higher proportion of accompanying persons (83%) than young people (64%) directed questions to clinicians. The proportion of young people asking questions was higher (84%) in the intervention phase than in the observation phase (71%). CONCLUSIONS: Interventions were acceptable and feasible. The Intervention phase was associated with YP asking more questions, which implies that the availability of interventions could promote interactivity.


Assuntos
Serviços de Saúde do Adolescente , Comunicação , Participação do Paciente , Adolescente , Criança , Tomada de Decisões , Endocrinologia/métodos , Estudos de Viabilidade , Feminino , Humanos , Masculino
4.
Diabet Med ; 33(2): 192-203, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26248789

RESUMO

AIM: To assess the effect of a 5-day structured education course (Kids in Control of Food; KICk-OFF) on biomedical and psychological outcomes in young people with Type 1 diabetes. METHODS: This was a cluster-randomized trial involving 31 UK paediatric centres. Participants were recruited prior to stratified centre randomization. Intervention centres delivered KICk-OFF courses, whereas control centres delivered usual care. Participants were 11-16 years of age and had Type 1 diabetes for at least one year. The KICk-OFF course was delivered by trained educators to eight participants per course. Glycaemic control and quality of life were measured at baseline, 6, 12 and 24 months. Secondary outcomes were hypoglycaemia, ketoacidosis, fear of hypoglycaemia and diabetes self-efficacy. RESULTS: Three hundred and ninety-six participants provided baseline data (199 intervention and 197 control). At 6 and 12 months the intervention group showed significantly improved total generic quality of life scores compared with controls (baseline: 80 vs. 82; 6 months: 82 vs. 82; P = 0.04). Across the whole intervention group mean HbA1c levels were not significantly different from controls; baseline HbA1c mean (95% confidence interval), 78 mmol/mol (75-81) vs. 76 mmol/mol (74-79) [9.3% (9-9.6%) vs. 9.1% (8.9-9.4%); 24 months: 77 mmol/mol (74-79) vs. 78 mmol/mol (75-81) (9.2% (8.9-9.4%) vs. 9.3% (9-9.6%)], adjusted mean difference, -2.0 mmol/mol (6.5-2.5) [2.3% (-2.7% to 2.4%)], P = 0.38. CONCLUSIONS: Attending a KICk-OFF course was associated with significantly improved total quality of life scores within 6 months. Glycaemic control, as measured by HbA1c , was no different at 24 months. (Clinical Trial Registry No: ISRCTN3704268).


Assuntos
Fenômenos Fisiológicos da Nutrição do Adolescente , Diabetes Mellitus Tipo 1/terapia , Dieta para Diabéticos , Ajustamento Emocional , Cooperação do Paciente , Educação de Pacientes como Assunto , Estresse Psicológico/prevenção & controle , Adolescente , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Análise por Conglomerados , Estudos de Coortes , Terapia Combinada , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/psicologia , Feminino , Seguimentos , Processos Grupais , Humanos , Hiperglicemia/prevenção & controle , Hipoglicemia/prevenção & controle , Masculino , Qualidade de Vida , Estresse Psicológico/complicações , Estresse Psicológico/etiologia , Reino Unido
5.
Nat Genet ; 19(2): 125-33, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9620767

RESUMO

During early mouse development the homeobox gene Hesx1 is expressed in prospective forebrain tissue, but later becomes restricted to Rathke's pouch, the primordium of the anterior pituitary gland. Mice lacking Hesx1 exhibit variable anterior CNS defects and pituitary dysplasia. Mutants have a reduced prosencephalon, anopthalmia or micropthalmia, defective olfactory development and bifurcations in Rathke's pouch. Neonates exhibit abnormalities in the corpus callosum, the anterior and hippocampal commissures, and the septum pellucidum. A comparable and equally variable phenotype in humans is septo-optic dysplasia (SOD). We have cloned human HESX1 and screened for mutations in affected individuals. Two siblings with SOD were homozygous for an Arg53Cys missense mutation within the HESX1 homeodomain which destroyed its ability to bind target DNA. These data suggest an important role for Hesx1/HESX1 in forebrain, midline and pituitary development in mouse and human.


Assuntos
Anormalidades Múltiplas/genética , Sequências Hélice-Alça-Hélice/genética , Proteínas de Homeodomínio/genética , Mutação , Hipófise/anormalidades , Septo Pelúcido/anormalidades , Anormalidades Múltiplas/patologia , Alelos , Sequência de Aminoácidos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , DNA/metabolismo , Desenvolvimento Embrionário e Fetal/genética , Feminino , Genótipo , Proteínas de Homeodomínio/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Fases de Leitura Aberta , Nervo Óptico/embriologia , Nervo Óptico/patologia , Linhagem , Hipófise/embriologia , Proteínas Repressoras , Septo Pelúcido/embriologia , Fatores de Transcrição HES-1
6.
Clin Exp Allergy ; 42(2): 284-92, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22181034

RESUMO

BACKGROUND: Although adrenaline is recommended as first line treatment for anaphylaxis, it is often not utilized. There has been a debate about when adrenaline autoinjectors should be prescribed and how many should be dispensed. OBJECTIVES: To see how many adrenaline autoinjectors were used during anaphylactic reactions and to determine why they were not used in situations where they were clinically indicated. METHODS: Patients were recruited prospectively at 14 paediatric allergy clinics throughout UK. Participants completed a questionnaire covering demographic data, atopic status and details of allergic reactions in the previous year and reasons for using more than one device. RESULTS: A total of 969 patients were recruited of whom 466 (48.1%, 95% CI: 37.9-58.2) had had at least one reaction in the previous year; 245 (25.3%, 95% CI: 16.2-34.4) of these reactions were anaphylaxis. An adrenaline autoinjector was used by 41 (16.7%, 95% CI: 11.7-21.3) participants experiencing anaphylaxis. Thirteen participants received more than one dose of adrenaline, for nine of these a health professional gave at least one. The commonest reasons for using more than one were severe breathing difficulties (40%), lack of improvement with first dose (20%) and miss-firing (13.3%). The commonest reasons for not using adrenaline in anaphylaxis were 'thought adrenaline unnecessary' (54.4%) and 'unsure adrenaline necessary' (19.1%). Many with wheeze did not use their autoinjector. CONCLUSIONS AND CLINICAL RELEVANCE: Adrenaline is used by only a minority of patients experiencing anaphylaxis in the community. Thirteen of the 41 patients with anaphylaxis who used their autoinjector needed another dose of adrenaline. Further research is needed to consider how to best encourage the usage of adrenaline when clinically indicated in anaphylaxis.


Assuntos
Agonistas alfa-Adrenérgicos/administração & dosagem , Anafilaxia/prevenção & controle , Epinefrina/administração & dosagem , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Injeções Subcutâneas/instrumentação , Injeções Subcutâneas/métodos , Masculino , Estudos Prospectivos , Reino Unido
7.
Arch Dis Child Educ Pract Ed ; 97(3): 98-105, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22611124

RESUMO

This expert opinion provides detailed guidance on assessing obesity in secondary paediatric practice. This guidance builds on existing recommendations from National Institute of Health and Clinical Excellence in the UK, and is evidence based where possible. Guidance is provided on which obese children and young people are appropriate to be seen in secondary care and relevant history and investigations, and guidance on when further investigation of causes and obesity-related comorbidity is appropriate.


Assuntos
Obesidade/etiologia , Obesidade/terapia , Encaminhamento e Consulta , Glicemia/análise , Índice de Massa Corporal , Criança , Jejum , Humanos , Insulina/análise , Lipídeos/sangue , Testes de Função Hepática , Anamnese , Síndrome Metabólica/diagnóstico , Exame Físico , Sono , Apneia Obstrutiva do Sono/diagnóstico
8.
Clin Endocrinol (Oxf) ; 75(4): 443-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21635277

RESUMO

CONTEXT: Increasing numbers of very low birth weight (VLBW) infants are surviving into adulthood because of improvements in neonatal intensive care. Adverse events in early life can have long-term effects through reprogramming of metabolic systems. OBJECTIVE: To determine whether young adult VLBW survivors have abnormalities of skeletal development or endocrine function. DESIGN: Cross-sectional, observational, case-control study. PARTICIPANTS: Thirty-seven VLBW subjects and 27 healthy controls at peak bone mass (mean age 23). MEASUREMENTS: Differences between cases and controls in body size, body composition, bone mass and bone geometry [assessed by dual-energy X-ray absorptiometry (DXA), hip structure analysis and peripheral quantitative computed tomography (pQCT)], bone turnover [urine N-terminal telopeptide of type I collagen (NTX), serum C-terminal telopeptide of type I collagen (CTX)], aminoterminal propeptide of type I procollagen (PINP) and bone alkaline phosphatase), hormones (sex steroids, IGF-1, PTH and 25-OH vitamin D) and insulin sensitivity (HOMA-IR and oral glucose tolerance testing). RESULTS: VLBW subjects had lower bone density at the lumbar spine (5.7%) and femoral neck (8.6%), which persisted after correction for bone size by the estimation of volumetric density (bone mineral apparent density). Urine NTX was higher in VLBW subjects than in controls, but there were no significant differences in other bone turnover markers. VLBW survivors had lower insulin sensitivity (mean INS-30 controls = 57.0, VLBW subjects = 94.3, P < 0.01), but there were no differences in whole body fat mass or truncal fat mass between VLBW subjects and controls. CONCLUSIONS: Young adult VLBW survivors have reduced bone density for their bone size and reduced insulin sensitivity, which may have significant implications for their risk of fracture and diabetes in later life.


Assuntos
Densidade Óssea/fisiologia , Recém-Nascido de muito Baixo Peso/sangue , Recém-Nascido de muito Baixo Peso/metabolismo , Resistência à Insulina/fisiologia , Absorciometria de Fóton , Adulto , Estudos de Casos e Controles , Colágeno Tipo I/sangue , Estudos Transversais , Feminino , Teste de Tolerância a Glucose , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/metabolismo , Humanos , Recém-Nascido , Masculino , Peptídeos/sangue , Adulto Jovem
9.
Scand J Immunol ; 71(6): 393-402, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20500691

RESUMO

Dendritic cells (DC) are an essential link between the innate and adaptive immune response. To become effective antigen-presenting cells DC need to undergo maturation, during which they up-regulate co-stimulatory molecules and produce cytokines. There is great interest in utilizing DC in vaccination regimes. Over recent years, Toll-like receptor (TLR) signalling has been recognized to be one of the major inducers of DC maturation. This study describes a mutant version of the TLR adaptor molecule MyD88 (termed MyD88lpr) as a novel adjuvant for vaccination regimes. MyD88lpr specifically activates DC by disrupting a DC intrinsic inhibitory mechanism, which is dependent on single immunoglobulin IL-1R-related. Moreover, MyD88lpr was able to induce an IgG2a-dominated response to a co-expressed antigen, suggesting Th1 immunity. However, when used as a vaccine adjuvant for Influenza nucleoprotein there was no significant difference in the lung viral titres during the infection. This study describes MyD88lpr as a potential adjuvant for vaccinations, which would be able to target DC specifically.


Assuntos
Células Dendríticas/imunologia , Fator 88 de Diferenciação Mieloide/imunologia , Receptores de Interleucina-1/imunologia , Adjuvantes Imunológicos/farmacologia , Animais , Anticorpos Antivirais/sangue , Células Dendríticas/efeitos dos fármacos , Feminino , Humanos , Imunidade Inata/imunologia , Vírus da Influenza A/imunologia , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/farmacologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/farmacologia , Organismos Livres de Patógenos Específicos , Células Th1/imunologia , Vacinação/métodos
11.
J Pediatr Endocrinol Metab ; 21(12): 1129-32, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19189685

RESUMO

BACKGROUND: There are few data in the paediatric literature on the normal cortisol response to stimulation during the low dose synacthen test (LDST) (1 microg). AIM: To examine the cortisol responses in children, subsequently presumed to be normal, who had an LDST during anterior pituitary function tests (APFTs). METHODS: A retrospective review of results in children with short stature and normal growth hormone levels. RESULTS: Of 33 children tested, seven had suboptimal cortisol responses based on accepted criteria (peak <500 nmol/l)--a false positive rate of 21%. Only three of these children had a repeat LDST, which was normal in all cases. The peak cortisol response (median 633, range, 417-1052 nmol/l) was inversely correlated with age (r = -0.44, p < 0.05). CONCLUSION: One in five tests did not meet normal criteria. This false positive rate (21%) should be borne in mind when interpreting synacthen tests to prevent overdiagnosis of adrenal insufficiency.


Assuntos
Insuficiência Adrenal/diagnóstico , Cosintropina , Hidrocortisona/sangue , Testes de Função Hipofisária/métodos , Adeno-Hipófise/fisiologia , Adolescente , Insuficiência Adrenal/sangue , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Reações Falso-Positivas , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos
12.
Eur J Endocrinol ; 157 Suppl 1: S61-5, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17785700

RESUMO

BACKGROUND: Phytosterolaemia (sitosterolaemia) is a rare autosomal recessive condition caused by mutations on the ABCG5 and ABCG8 gut transporter proteins. This leads to accumulation of plant-derived cholesterol-like molecules in blood and tissues. CASE: We describe a family of Bangladesh origin, where three siblings (two males and one female) have homozygous mutations for phytosterolaemia, and exhibit short stature and adrenal failure with the female having ovarian failure. FINDINGS: The index case (18-year-old female) and her sibling (16 years) have adrenal insufficiency with hyperpigmentation and raised levels of ACTH, at 367 and 690 ng/l respectively. The youngest child at 7 years has normal adrenal function. In addition, the index case has ovarian failure and sibling 2 has partial growth hormone deficiency. CONCLUSION: Although short stature is a recognised phenomenon, no previous association has been made between phytosterolaemia and other endocrine abnormalities. We postulate that the elevated plant sterol levels in phytosterolaemia may interfere with endocrine hormone synthesis; in particular, we present evidence that adrenal cholesterol metabolism may be preferentially affected, accounting for the adrenal insufficiency.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Insuficiência Adrenal/etiologia , Genes Recessivos , Lipoproteínas/genética , Mutação , Fitosteróis/sangue , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Adolescente , Insuficiência Adrenal/sangue , Hormônio Adrenocorticotrópico/sangue , Estatura , Criança , Feminino , Transtornos do Crescimento/etiologia , Hormônio do Crescimento/deficiência , Homozigoto , Humanos , Hiperpigmentação/etiologia , Masculino , Linhagem , Insuficiência Ovariana Primária/etiologia
13.
Arch Dis Child ; 102(6): 503-508, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27998884

RESUMO

BACKGROUND: Many infants born prematurely experience growth failure following delivery, with subsequent catch-up growth. Traditionally catch-up was thought to be complete in the first few years of life. Most studies have focused on groups of infants defined by birth weight, for example <1500 g, resulting in disproportionate numbers of small for gestational age infants. This study aimed to determine whether appropriate weight for gestation (AGA) preterm born children reach their expected adult height when compared with term controls. METHODOLOGY: This UK based prospective longitudinal cohort study recruited 204 preterm children born at a tertiary neonatal unit during 1994 and 50 matched controls. Growth parameters have been assessed annually until the completion of growth. RESULTS: There was no significant difference in the final height SD score (SDS) of children born at term (n=30) and those born prematurely and AGA (n=70) (0.45 term vs 0.22 preterm). Catch-up growth however, continued throughout the whole of childhood. When the difference between final height SDS and mid-parental height SDS were compared, there were again no significant differences (0.13 term vs 0.03 preterm). CONCLUSIONS: Those born prematurely with an AGA achieve a comparable adult height to children born at term, however, catch-up growth continues for much longer than traditionally thought.


Assuntos
Estatura/fisiologia , Recém-Nascido Prematuro/crescimento & desenvolvimento , Adulto , Envelhecimento/fisiologia , Antropometria/métodos , Estudos de Casos e Controles , Desenvolvimento Infantil/fisiologia , Feminino , Idade Gestacional , Crescimento/fisiologia , Humanos , Recém-Nascido , Estudos Longitudinais , Masculino , Valores de Referência , Caracteres Sexuais , Nascimento a Termo
14.
J Natl Cancer Inst ; 60(2): 317-20, 1978 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-202715

RESUMO

Diets containing either 49.5% or 32% casein or fish protein concentrate (FPC) were fed to young rainbow trout (Salmo gairdneri) for 12 months. Five levels [0, 2, 6, 18, and 54 parts per billion (ppb)] of aflatoxin B1 (AFB1) were given in each of four different diets. A 30-fish sample was taken at 6, 9, and 12 months to determine the influence of diet on the carcinogenicity of AFB1. Both levels of casein produced similar hepatoma incidences at each level of AFB1. The diet high in FPC produced more tumours than did the casein diets at 2, 6, and 18 ppb AFB1, whereas fish fed the diet low in FPC had a significantly (P less than 0.05) lower hepatoma incidence than did the other three groups. The liver size (percent body wt) was smaller at higher toxin levels in all instances. The growth of fish given 32% casein was less than that of the other groups.


Assuntos
Aflatoxinas/toxicidade , Carcinoma Hepatocelular/etiologia , Proteínas Alimentares/administração & dosagem , Neoplasias Hepáticas/etiologia , Aflatoxinas/administração & dosagem , Animais , Peso Corporal , Caseínas/administração & dosagem , Produtos Pesqueiros , Neoplasias Experimentais/etiologia , Fatores de Tempo , Truta
15.
J Natl Cancer Inst ; 64(6): 1503-9, 1980 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6929388

RESUMO

Versicolorin A (VA) and sterigmatocystin (ST) are biosynthetic precursors of aflatoxin B1 (AFB1). The carcinogenicity of these compounds relative to AFB1 was determined with the use of rainbow trout (Salmo gairdneri) embryo exposure. Exposure of 14-day rainbow trout embryos to a 0.5-ppm aqueous suspension of ST for 1 hour produced a 13% incidence of hepatocellular carcinomas among survivors 1 year later. Similar exposure of trout eggs to a 0.5-ppm solution of AFB1 produced a 53% incidence among survivors. Subsequent exposure of 21-day rainbow trout embryos to 5- and 25-ppm solutions of VA resulted in hepatocellular carcinoma incidences among survivors of 42 and 68%, respectively, at 12 months. A 0.5-ppm AFB1 positive control group had a 68% incidence among survivors of hepatocellular carcinomas at 1 year. These results established the carcinogenicity of VA for the first time and confirmed previous reports of ST carcinogenicity. Both compounds were of sufficient potencies to warrant caution as possible human health hazards.


Assuntos
Aflatoxinas/toxicidade , Antraquinonas/toxicidade , Neoplasias Hepáticas Experimentais/induzido quimicamente , Salmonidae/fisiologia , Esterigmatocistina/toxicidade , Truta/fisiologia , Xantenos/toxicidade , Animais , Neoplasias Hepáticas Experimentais/patologia , Truta/embriologia
16.
J Natl Cancer Inst ; 60(5): 1133-9, 1978 May.
Artigo em Inglês | MEDLINE | ID: mdl-205663

RESUMO

Liver cancer in rainbow trout was induced by exposure of fertile eggs to an aqueous, 0.5 ppm (microgram/ml) solution of aflatoxin B1 (AFB1) for 1 hour. Single treatments, given on alternate days during the embryonic period, produced a low cancer incidence (less than 20%) prior to formation of the embryonic liver on day 14, but a steadily increasing incidence from day 15 (31.7%) until day 23 (58.3%), in fish examined 1 year later. Treatment of trout eggs with [14C]AFB1 was used to quantitate the amount of AFB1 absorbed by the eggs. Twenty-one-day-old rainbow trout eggs absorbed approximately 30 ng of [14C]AFB1 during a 1-hour exposure to 0.5 ppm aqueous [14C]AFB1. After 1 day 85-90% of the [14C]AFB1 was either metabolized and excreted or leached from the egg. The residual [14C]AFB1 remained constant until hatching when an additional 50% was lost. Comparison of the amount of AFB1 absorbed by eggs with the amount of AFB1 consumed per fish during a 1-year feeding trial at 4 ppb in the diet indicates that the trout embryo is even more sensitive than juvenile trout to the carcinogenic properties of AFB1.


Assuntos
Aflatoxinas/toxicidade , Carcinoma Hepatocelular/induzido quimicamente , Neoplasias Hepáticas/induzido quimicamente , Aflatoxinas/administração & dosagem , Aflatoxinas/metabolismo , Animais , Carcinoma Hepatocelular/patologia , Dieta , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Feminino , Neoplasias Hepáticas/patologia , Masculino , Neoplasias Experimentais/induzido quimicamente , Fatores de Tempo , Truta
17.
J Natl Cancer Inst ; 64(3): 523-8, 1980 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6766512

RESUMO

Aflatoxin Q1 (AFQ1), the major microsomal biotransformation product of aflatoxin B1 (AFB1) formed in vitro by monkey and human liver preparations, was fed to rainbow trout (Salmo gairdneri) in a semipurified diet at levels of 20 ppb for 1 year and 100 ppb for 10 months. As a test for carcinogenicity in hatched fish, it was also used at 1 ppm in a water solution and exposed for 1 hour to fertile trout eggs. The 20-ppb dietary exposure and 1-ppm egg exposure failed to elicit a carcinogenic response; however, the 100-ppb dietary exposure produced a 10.6% incidence of hepatocellular carcinomas at the end of 1 year. Administration of 50 ppm methyl sterculate, a cyclopropenoid fatty acid, in combination with 100 ppb AFQ1 resulted in a synergistic tumor response similar to that previously noted with administration of AFB1 plus aflatoxin M1. The tumor incidence was 89.1% in the fish on the combined diet. These results indicated that AFQ1 was approximately 100 times less carcinogenic than was AFB1. This comparison of carcinogenic potencies was very similar to the comparison of the relative mutagenicities of the two compounds in the Ames bacterial mutagen assay system.


Assuntos
Aflatoxinas/toxicidade , Ciclopropanos/farmacologia , Ácidos Graxos Monoinsaturados , Ácidos Graxos Insaturados/farmacologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Aflatoxinas/metabolismo , Animais , Biotransformação , Cocarcinogênese , Sinergismo Farmacológico , Haplorrinos , Técnicas In Vitro , Neoplasias Hepáticas Experimentais/patologia , Microssomos Hepáticos/metabolismo , Truta
18.
Cancer Res ; 41(3): 1011-4, 1981 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7459848

RESUMO

Aflatoxicol (AFL), a major metabolite of aflatoxin B1 (AFB1) in the Mt. Shasta rainbow trout (Salmo gairdneri), was found to produce hepatocellular carcinoma in trout. It was administered in a casein diet to duplicate groups of 120 fingering trout. In the same manner, additional duplicate groups received one of the following: no toxicant; AFB1; the diastereomer of AFL (AFL'); cyclopropenoid fatty acids (CPFA); and CPFA plus AFB1, AFL, and AFL'. Eight months after the initiation of the study, the following incidences of carcinoma were observed: control (0%); 20 ppb AFB1 (56%); 29 ppb AFL (26%); 61 ppb AFL' (0%); 50 ppm CPFA (3%); 20 ppb AFB1 plus 50 ppm CPFA (96%); 29 ppb AFL plus 50 ppm CPFA (94%); and 61 ppb AFL' plus 50 ppm CPFA (55%), showing both the carcinogenicity of AFL and the synergistic effects of CPFA. Twelve-month incidences were correspondingly higher in all cases. Aflatoxin M1, another metabolite of AFB1 in rainbow trout, was reported previously to be carcinogenic in trout. These results support the hypothesis that metabolism in rainbow trout does not effectively detoxify AFB1, but rather the formation of AFL extends the carcinogenicity of AFB1 and may contribute to the high sensitivity of rainbow trout to AFB.


Assuntos
Aflatoxinas , Ácidos Graxos Insaturados , Neoplasias Hepáticas Experimentais/induzido quimicamente , Salmonidae/fisiologia , Truta/fisiologia , Aflatoxinas/metabolismo , Animais , Biotransformação , Sinergismo Farmacológico , Fígado/metabolismo
19.
J Clin Oncol ; 13(10): 2503-7, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7595700

RESUMO

PURPOSE: To determine the effect of cranial irradiation (18 Gy and 24 Gy) on pubertal growth in young adult survivors of childhood acute lymphoblastic leukemia (ALL). PATIENTS AND METHODS: Final height (FH) and pubertal growth were retrospectively examined in 142 young adult survivors of childhood ALL. All were in first remission and had received either 18 or 24 Gy of cranial irradiation. Eighty-four children (48 girls) were treated with 24 Gy and 58 (35 girls) with 18 Gy. None had received either testicular or spinal irradiation. Timing and duration of puberty were studied in 110 patients. RESULTS: Significant reduction in height standard deviation score (SDS) from diagnosis to FH was seen in both sexes and in both dose groups. In girls, in both dose groups, mean age at peak height velocity (PHV) and mean age at menarche occurred significantly earlier than in the normal population. In boys, there was a normal timing of PHV. The amplitude of PHV was significantly reduced in both sexes and in both dose groups. Parameters of pubertal duration (PHV to menarche, PHV to FH, and menarche to FH) were not significantly different from normal population values. CONCLUSION: In conclusion, puberty occurred early in girls, but not in boys. Amplitude of PHV was reduced in both sexes, with no reduction in the duration of puberty. It is likely that disturbances of both timing and quality of growth during puberty contribute to the loss of standing height and body disproportion seen in these children.


Assuntos
Neoplasias Encefálicas/prevenção & controle , Irradiação Craniana/efeitos adversos , Crescimento/efeitos da radiação , Leucemia-Linfoma Linfoblástico de Células Precursoras/radioterapia , Puberdade/efeitos da radiação , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Asparaginase/uso terapêutico , Estatura/efeitos da radiação , Criança , Terapia Combinada , Daunorrubicina/uso terapêutico , Feminino , Seguimentos , Humanos , Masculino , Menarca/efeitos da radiação , Metotrexato/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/fisiopatologia , Prednisolona/uso terapêutico , Radioterapia/efeitos adversos , Estudos Retrospectivos , Fatores Sexuais , Vincristina/uso terapêutico
20.
Diabetes ; 37(7): 969-73, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3133261

RESUMO

The relationships between nerve polyol levels and both nerve conduction velocity (NCV) and resistance to ischemic conduction block (RICB) in streptozocin-induced diabetic rats were examined in two studies. In the first study, sciatic NCV and RICB of the tail nerve, assessed by measuring the time to disappearance of the nerve action potential after the tail was rendered ischemic, were measured in nondiabetic rats, untreated diabetic rats, and diabetic rats given Statil, an aldose reductase inhibitor (ARI). Sciatic NCV was lower in the untreated diabetic animals than in control animals (P less than .05), and RICB of the tail nerve was greater (P less than .001). Treatment with the ARI completely prevented the slowing of NCV but had no significant effect on the increase in RICB. In the second study, similar groups of rats were treated with either ARI, insulin, or myo-inositol. Sciatic NCV was lower in the untreated diabetic rats than in the nondiabetic rats (P less than .001). In diabetic rats treated with the ARI and in those treated with insulin, NCV was greater than in the untreated diabetic rats (P less than .05 and P less than .001, respectively) and was not significantly different from the nondiabetic rats. NCV in the myo-inositol-treated rats was not significantly different from that in the untreated diabetic rats. RICB was assessed by measuring the decline in sciatic nerve action potential amplitude at minute intervals after death.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Aldeído Redutase/antagonistas & inibidores , Diabetes Mellitus Experimental/fisiopatologia , Isquemia/fisiopatologia , Condução Nervosa , Desidrogenase do Álcool de Açúcar/antagonistas & inibidores , Potenciais de Ação , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Inositol/farmacologia , Insulina/uso terapêutico , Cinética , Masculino , Ftalazinas/farmacologia , Ratos , Ratos Endogâmicos , Nervo Isquiático/fisiopatologia , Sorbitol/metabolismo , Cauda/irrigação sanguínea , Cauda/inervação
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