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1.
Hum Reprod ; 35(4): 913-928, 2020 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-32325494

RESUMEN

STUDY QUESTION: Are maternal serum phthalate metabolite, phenol and paraben concentrations measured at 10-17 weeks of gestation associated with male infant genital developmental outcomes, specifically cryptorchidism, anogenital distance (AGD), penile length and testicular descent distance, at birth and postnatally? SUMMARY ANSWER: Maternal serum bisphenol A (BPA) concentration at 10-17 weeks of gestation was positively associated with congenital or postnatally acquired cryptorchidism, and n-propyl paraben (n-PrP) concentration was associated with shorter AGD from birth to 24 months of age. WHAT IS KNOWN ALREADY: Male reproductive disorders are increasing in prevalence, which may reflect environmental influences on foetal testicular development. Animal studies have implicated phthalates, BPA and parabens, to which humans are ubiquitously exposed. However, epidemiological studies have generated conflicting results and have often been limited by small sample size and/or measurement of chemical exposures outside the most relevant developmental window. STUDY DESIGN, SIZE, DURATION: Case-control study of cryptorchidism nested within a prospective cohort study (Cambridge Baby Growth Study), with recruitment of pregnant women at 10-17 postmenstrual weeks of gestation from a single UK maternity unit between 2001 and 2009 and 24 months of infant follow-up. Of 2229 recruited women, 1640 continued with the infancy study after delivery, of whom 330 mothers of 334 male infants (30 with congenital cryptorchidism, 25 with postnatally acquired cryptorchidism and 279 unmatched controls) were included in the present analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS: Maternal blood was collected at enrolment, and serum levels of 16 phthalate metabolites, 9 phenols (including BPA) and 6 parabens were measured using liquid chromatography/tandem mass spectrometry. Logistic regression was used to model the association of cryptorchidism with serum chemical concentrations, adjusting for putative confounders. Additionally, offspring AGD, penile length and testicular descent distance were assessed at 0, 3, 12, 18 and 24 months of age, and age-specific Z scores were calculated. Associations between serum chemical levels and these outcomes were tested using linear mixed models. MAIN RESULTS AND THE ROLE OF CHANCE: Maternal serum BPA concentration was associated with offspring all-type cryptorchidism both when considered as a continuous exposure (adjusted odds ratio per log10 µg/l: 2.90, 95% CI 1.31-6.43, P = 0.009) and as quartiles (phet = 0.002). Detection of n-PrP in maternal serum was associated with shorter AGD (by 0.242 standard deviations, 95% CI 0.051-0.433, P = 0.01) from birth to 24 months of age; this reduction was independent of body size and other putative confounders. We did not find any consistent associations with offspring outcomes for the other phenols, parabens, and phthalate metabolites measured. LIMITATIONS, REASONS FOR CAUTION: We cannot discount confounding by other demographic factors or endocrine-disrupting chemicals. There may have been misclassification of chemical exposure due to use of single serum measurements. The cohort was not fully representative of pregnant women in the UK, particularly in terms of smoking prevalence and maternal ethnicity. WIDER IMPLICATIONS OF THE FINDINGS: Our observational findings support experimental evidence that intrauterine exposure to BPA and n-PrP during early gestation may adversely affect male reproductive development. More evidence is required before specific public health recommendations can be made. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by a European Union Framework V programme, the World Cancer Research Fund International, the Medical Research Council (UK), Newlife the Charity for Disabled Children, the Mothercare Group Foundation, Mead Johnson Nutrition and the National Institute for Health Research Cambridge Comprehensive Biomedical Research Centre. Visiting Fellowship (J.M.): Regional Programme 'Jiménez de la Espada' for Research Mobility, Cooperation and Internationalization, Seneca Foundation-Science and Technology Agency for the Region of Murcia (No. 20136/EE/17). K.O. is supported by the Medical Research Council (UK) (Unit Programme number: MC_UU_12015/2). The authors declare no conflict of interest.


Asunto(s)
Parabenos , Fenoles , Compuestos de Bencidrilo , Estudios de Casos y Controles , Niño , Femenino , Humanos , Lactante , Masculino , Fenoles/toxicidad , Embarazo , Estudios Prospectivos
3.
Diabetes Metab ; 43(4): 323-331, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28392167

RESUMEN

AIM: We hypothesised that some of the genetic risk for gestational diabetes (GDM) is due to the fetal genome affecting maternal glucose concentrations. Previously, we found associations between fetal IGF2 gene variants and maternal glucose concentrations in late pregnancy. METHODS: In the present study, we tested associations between SNP alleles from 15 fetal imprinted genes and maternal glucose concentrations in late pregnancy in the Cambridge Baby Growth and Wellbeing cohorts (1160 DNA trios). RESULTS: Four fetal SNP alleles with the strongest univariate associations: paternally-transmitted IGF2 rs10770125 (P-value=2×10-4) and INS rs2585 (P-value=7×10-4), and maternally-transmitted KCNQ1(OT1) rs231841 (P-value=1×10-3) and KCNQ1(OT1) rs7929804 (P-value=4×10-3), were used to construct a composite fetal imprinted gene allele score which was associated with maternal glucose concentrations (P-value=4.3×10-6, n=981, r2=2.0%) and GDM prevalence (odds ratio per allele 1.44 (1.15, 1.80), P-value=1×10-3, n=89 cases and 899 controls). Meta-analysis of the associations including data from 1367 Hyperglycaemia and Adverse Pregnancy Outcome Study participants confirmed the paternally-transmitted fetal IGF2/INS SNP associations (rs10770125, P-value=3.2×10-8, rs2585, P-value=3.6×10-5) and the composite fetal imprinted gene allele score association (P-value=1.3×10-8), but not the maternally-transmitted fetal KCNQ1(OT1) associations (rs231841, P-value=0.4; rs7929804, P-value=0.2). CONCLUSION: This study suggests that polymorphic variation in fetal imprinted genes, particularly in the IGF2/INS region, contribute a small but significant part to the risk of raised late pregnancy maternal glucose concentrations.


Asunto(s)
Alelos , Glucemia/genética , Diabetes Gestacional/genética , Impresión Genómica , Polimorfismo de Nucleótido Simple , Adulto , Diabetes Gestacional/sangre , Femenino , Humanos , Insulina/genética , Factor II del Crecimiento Similar a la Insulina/genética , Canal de Potasio KCNQ1/genética , Embarazo , Resultado del Embarazo
4.
J Pediatr Urol ; 13(5): 498.e1-498.e6, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28351649

RESUMEN

BACKGROUND: Complete androgen insensitivity syndrome (CAIS) is an X-linked recessive disorder of sex development (DSD) where affected individuals are phenotypically female, but have an XY karyotype and testes. The risk of gonadal tumour development in CAIS may increase with age; incidence rates have been reported to be 0.8-22% in patients who have retained their gonads into adulthood. Consequently, gonadectomy has been recommended either during childhood or after puberty is complete, although there is no consensus on the optimal timing for this procedure. OBJECTIVE AND HYPOTHESES: To establish the frequency of histological abnormalities in CAIS in relation to the age at gonadectomy. METHOD: Data were collected from the Cambridge DSD database on patients with CAIS (n = 225; age range 3-88 years) who had undergone gonadectomy, and their age of gonadectomy, gonadal histology and immunohistochemistry. RESULTS: Evaluable data were obtained from 133 patients. Median age at gonadectomy was 14.0 years (range: 18 days-68 years). Pubertal status was: prepuberty, n = 62; postpuberty, n = 68. Thirteen cases were aged >20 years at gonadectomy. The pattern of histology is summarised in the Summary table. DISCUSSION: In this large case series of CAIS patients who had undergone gonadectomy, while the combined malignant and premalignant gonadal histology prevalence was 6.0%, the findings confirm the low occurrence of gonadal malignancy in CAIS, with a frequency of 1.5%. The two cases of malignancy were postpubertal. Germ cell neoplasia in situ (GCNIS) was observed in six cases, of which one occurred prepuberty and five postpuberty. The study highlighted difficulties in diagnosis of GCNIS and the need for histological analysis in expert centres. CONCLUSION: The results support the current recommendation that gonads in CAIS can be retained until early adulthood. The small number of individuals with gonadectomy after age 20 years do not allow firm conclusion regarding later adulthood. Therefore, it is recommended that the option of gonadectomy be discussed in adulthood. Some form of regular surveillance of the gonads is then recommended, although none of the available options are ideal.


Asunto(s)
Síndrome de Resistencia Androgénica/epidemiología , Síndrome de Resistencia Androgénica/cirugía , Gónadas/cirugía , Neoplasias de Células Germinales y Embrionarias/epidemiología , Neoplasias de Células Germinales y Embrionarias/cirugía , Adolescente , Adulto , Factores de Edad , Síndrome de Resistencia Androgénica/diagnóstico , Biopsia con Aguja , Niño , Preescolar , Estudios de Cohortes , Comorbilidad , Bases de Datos Factuales , Femenino , Estudios de Seguimiento , Gónadas/patología , Humanos , Inmunohistoquímica , Masculino , Neoplasias de Células Germinales y Embrionarias/patología , Ovario/patología , Ovario/cirugía , Estudios Retrospectivos , Medición de Riesgo , Desarrollo Sexual/fisiología , Testículo/patología , Testículo/cirugía , Resultado del Tratamiento , Adulto Joven
5.
Hum Reprod ; 31(11): 2642-2650, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27609981

RESUMEN

STUDY QUESTION: What is the relationship between maternal paracetamol intake during the masculinisation programming window (MPW, 8-14 weeks of gestation) and male infant anogenital distance (AGD), a biomarker for androgen action during the MPW? SUMMARY ANSWER: Intrauterine paracetamol exposure during 8-14 weeks of gestation is associated with shorter AGD from birth to 24 months of age. WHAT IS ALREADY KNOWN: The increasing prevalence of male reproductive disorders may reflect environmental influences on foetal testicular development during the MPW. Animal and human xenograft studies have demonstrated that paracetamol reduces foetal testicular testosterone production, consistent with reported epidemiological associations between prenatal paracetamol exposure and cryptorchidism. STUDY DESIGN, SIZE, DURATION: Prospective cohort study (Cambridge Baby Growth Study), with recruitment of pregnant women at ~12 post-menstrual weeks of gestation from a single UK maternity unit between 2001 and 2009, and 24 months of infant follow-up. Of 2229 recruited women, 1640 continued with the infancy study after delivery, of whom 676 delivered male infants and completed a medicine consumption questionnaire. PARTICIPANTS/MATERIALS, SETTING, METHOD: Mothers self-reported medicine consumption during pregnancy by a questionnaire administered during the perinatal period. Infant AGD (measured from 2006 onwards), penile length and testicular descent were assessed at 0, 3, 12, 18 and 24 months of age, and age-specific Z scores were calculated. Associations between paracetamol intake during three gestational periods (<8 weeks, 8-14 weeks and >14 weeks) and these outcomes were tested by linear mixed models. Two hundred and twenty-five (33%) of six hundred and eighty-one male infants were exposed to paracetamol during pregnancy, of whom sixty-eight were reported to be exposed during 8-14 weeks. AGD measurements were available for 434 male infants. MAIN RESULTS AND THE ROLE OF CHANCE: Paracetamol exposure during 8-14 weeks of gestation, but not any other period, was associated with shorter AGD (by 0.27 SD, 95% CI 0.06-0.48, P = 0.014) from birth to 24 months of age. This reduction was independent of body size. Paracetamol exposure was not related to penile length or testicular descent. LIMITATIONS, REASONS FOR CAUTION: Confounding by other drugs or endocrine-disrupting chemicals cannot be discounted. The cohort was not fully representative of pregnant women in the UK, particularly in terms of maternal ethnicity and smoking prevalence. There is likely to have been misclassification of paracetamol exposure due to recall error. WIDER IMPLICATIONS OF THE FINDINGS: Our observational findings support experimental evidence that intrauterine paracetamol exposure during the MPW may adversely affect male reproductive development. STUDY FUNDING/COMPETING INTERESTS: This work was supported by a European Union Framework V programme, the World Cancer Research Fund International, the Medical Research Council (UK), the Newlife Foundation for Disabled Children, the Evelyn Trust, the Mothercare Group Foundation, Mead Johnson Nutrition, and the National Institute for Health Research Cambridge Comprehensive Biomedical Research Centre. The authors declare no conflict of interest.


Asunto(s)
Acetaminofén/administración & dosificación , Canal Anal/anatomía & histología , Efectos Tardíos de la Exposición Prenatal , Testículo/anatomía & histología , Canal Anal/efectos de los fármacos , Biomarcadores , Pesos y Medidas Corporales , Femenino , Humanos , Recién Nacido , Masculino , Embarazo , Testículo/efectos de los fármacos
6.
Andrology ; 4(4): 616-25, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26846869

RESUMEN

Abnormal foetal testis development has been proposed to underlie common disorders of the male reproductive system such as cryptorchidism, hypospadias, reduced semen quality and testicular germ cell tumour, which are regarded as components of a 'testicular dysgenesis syndrome'. The increasing trends and geographical variation in their incidence have been suggested to result from in utero exposure to environmental chemicals acting as endocrine disruptors. In rodents, the anogenital distance (AGD), measured from the anus to the base of genital tubercle, is a sensitive biomarker of androgen exposure during a critical embryonic window of testis development. In humans, several epidemiological studies have shown alterations in AGD associated with prenatal exposure to several chemicals with potential endocrine disrupting activity. However, the link between AGD and androgen exposure in humans is not well-defined. This review focuses on the current evidence for such a relationship. As in rodents, a clear gender difference is detected during foetal development of the AGD in humans which is maintained thereafter. Reduced AGD in association with clinically relevant outcomes of potential environmental exposures, such as cryptorchidism or hypospadias, is in keeping with AGD as a marker of foetal testicular function. Furthermore, AGD may reflect variations in prenatal androgen exposure in healthy children as shorter AGD at birth is associated with reduced masculine play behaviour in preschool boys. Several studies provide evidence linking shorter AGD with lower fertility, semen quality and testosterone levels in selected groups of adults attending andrology clinics. Overall, the observational data in humans are consistent with experimental studies in animals and support the use of AGD as a biomarker of foetal androgen exposure. Future studies evaluating AGD in relation to reproductive hormones in both infants and adults, and to gene polymorphisms, will help to further delineate the effect of prenatal and postnatal androgen exposures on AGD.


Asunto(s)
Andrógenos/fisiología , Genitales Femeninos/anatomía & histología , Genitales Masculinos/anatomía & histología , Efectos Tardíos de la Exposición Prenatal , Antropometría , Femenino , Humanos , Masculino , Embarazo
7.
N Engl J Med ; 373(22): 2129-2140, 2015 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-26379095

RESUMEN

BACKGROUND: The feasibility, safety, and efficacy of prolonged use of an artificial beta cell (closed-loop insulin-delivery system) in the home setting have not been established. METHODS: In two multicenter, crossover, randomized, controlled studies conducted under free-living home conditions, we compared closed-loop insulin delivery with sensor-augmented pump therapy in 58 patients with type 1 diabetes. The closed-loop system was used day and night by 33 adults and overnight by 25 children and adolescents. Participants used the closed-loop system for a 12-week period and sensor-augmented pump therapy (control) for a similar period. The primary end point was the proportion of time that the glucose level was between 70 mg and 180 mg per deciliter for adults and between 70 mg and 145 mg per deciliter for children and adolescents. RESULTS: Among adults, the proportion of time that the glucose level was in the target range was 11.0 percentage points (95% confidence interval [CI], 8.1 to 13.8) greater with the use of the closed-loop system day and night than with control therapy (P<0.001). The mean glucose level was lower during the closed-loop phase than during the control phase (difference, -11 mg per deciliter; 95% CI, -17 to -6; P<0.001), as were the area under the curve for the period when the glucose level was less than 63 mg per deciliter (39% lower; 95% CI, 24 to 51; P<0.001) and the mean glycated hemoglobin level (difference, -0.3%; 95% CI, -0.5 to -0.1; P=0.002). Among children and adolescents, the proportion of time with the nighttime glucose level in the target range was higher during the closed-loop phase than during the control phase (by 24.7 percentage points; 95% CI, 20.6 to 28.7; P<0.001), and the mean nighttime glucose level was lower (difference, -29 mg per deciliter; 95% CI, -39 to -20; P<0.001). The area under the curve for the period in which the day-and-night glucose levels were less than 63 mg per deciliter was lower by 42% (95% CI, 4 to 65; P=0.03). Three severe hypoglycemic episodes occurred during the closed-loop phase when the closed-loop system was not in use. CONCLUSIONS: Among patients with type 1 diabetes, 12-week use of a closed-loop system, as compared with sensor-augmented pump therapy, improved glucose control, reduced hypoglycemia, and, in adults, resulted in a lower glycated hemoglobin level. (Funded by the JDRF and others; AP@home04 and APCam08 ClinicalTrials.gov numbers, NCT01961622 and NCT01778348.).


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hipoglucemiantes/efectos adversos , Sistemas de Infusión de Insulina , Insulina/efectos adversos , Adolescente , Adulto , Algoritmos , Niño , Estudios Cruzados , Diabetes Mellitus Tipo 1/sangre , Diseño de Equipo , Femenino , Hemoglobina Glucada/análisis , Humanos , Hipoglucemia/inducido químicamente , Hipoglucemiantes/administración & dosificación , Bombas de Infusión Implantables , Insulina/administración & dosificación , Sistemas de Infusión de Insulina/efectos adversos , Masculino , Persona de Mediana Edad
8.
Diabetes Obes Metab ; 17(12): 1173-9, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26257323

RESUMEN

AIMS: To evaluate safety, efficacy and glucose turnover during closed-loop with meal announcement using reduced prandial insulin boluses in adolescents with type 1 diabetes (T1D). METHODS: We conducted a randomized crossover study comparing closed-loop therapy with standard prandial insulin boluses versus closed-loop therapy with prandial boluses reduced by 25%. Eight adolescents with T1D [3 males; mean (standard deviation) age 15.9 (1.5) years, glycated haemoglobin 74 (17) mmol/mol; median (interquartile range) total daily dose 0.9 (0.7, 1.1) IU/kg/day] were studied on two 36-h-long visits. In random order, subjects received closed-loop therapy with either standard or reduced insulin boluses administered with main meals (50-80 g carbohydrates) but not with snacks (15-30 g carbohydrates). Stable-label tracer dilution methodology measured total glucose appearance (Ra_total) and glucose disposal (Rd). RESULTS: The median (interquartile range) time spent in target (3.9-10 mmol/l) was similar between the two interventions [74 (66, 84)% vs 80 (65, 96)%; p = 0.87] as was time spent above 10 mmol/l [21.8 (16.3, 33.5)% vs 18.0 (4.1, 34.2)%; p = 0.87] and below 3.9 mmol/l [0 (0, 1.5)% vs 0 (0, 1.8)%; p = 0.88]. Mean plasma glucose was identical during the two interventions [8.4 (0.9) mmol/l; p = 0.98]. Hypoglycaemia occurred once 1.5 h post-meal during closed-loop therapy with standard bolus. Overall insulin delivery was lower with reduced prandial boluses [61.9 (55.2, 75.0) vs 72.5 (63.6, 80.3) IU; p = 0.01] and resulted in lower mean plasma insulin concentration [186 (171, 260) vs 252 (198, 336) pmol/l; p = 0.002]. Lower plasma insulin was also documented overnight [160 (136, 192) vs 191 (133, 252) pmol/l; p = 0.01, pooled nights]. Ra_total was similar [26.3 (21.9, 28.0) vs 25.4 (21.0, 29.2) µmol/kg/min; p = 0.19] during the two interventions as was Rd [25.8 (21.0, 26.9) vs 25.2 (21.2, 28.8) µmol/kg/min; p = 0.46]. CONCLUSIONS: A 25% reduction in prandial boluses during closed-loop therapy maintains similar glucose control in adolescents with T1D whilst lowering overall plasma insulin levels. It remains unclear whether closed-loop therapy with a 25% reduction in prandial boluses would prevent postprandial hypoglycaemia.


Asunto(s)
Glucemia/análisis , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hipoglucemia/prevención & control , Hipoglucemiantes/administración & dosificación , Sistemas de Infusión de Insulina , Insulina/administración & dosificación , Monitoreo Fisiológico , Adolescente , Algoritmos , Estudios Cruzados , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/metabolismo , Esquema de Medicación , Inglaterra/epidemiología , Femenino , Carga Glucémica , Humanos , Hiperinsulinismo/inducido químicamente , Hiperinsulinismo/epidemiología , Hiperinsulinismo/prevención & control , Hipoglucemia/inducido químicamente , Hipoglucemia/epidemiología , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/sangre , Hipoglucemiantes/uso terapéutico , Inyecciones Subcutáneas , Insulina/efectos adversos , Insulina/sangre , Insulina/uso terapéutico , Resistencia a la Insulina , Masculino , Comidas , Riesgo
9.
Diabetologia ; 56(5): 1108-17, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23435829

RESUMEN

AIMS/HYPOTHESIS: Successful postprandial glycaemia management requires understanding of absorption patterns after meals containing variable complex carbohydrates. We studied eight young participants with type 1 diabetes to investigate a large low-glycaemic-load (LG) meal and another eight participants to investigate a high-glycaemic-load (HG) meal matched for carbohydrates (121 g). METHODS: On Visit 1, participants consumed an evening meal. On follow-up Visit 2, a variable-target glucose clamp was performed to reproduce glucose and insulin levels from Visit 1. Adopting stable-label tracer dilution methodology, we measured endogenous glucose production on Visit 2 and subtracted it from total glucose appearance measured on Visit 1 to obtain meal-attributable glucose appearance. RESULTS: After the LG meal, 25%, 50% and 75% of cumulative glucose appearance was at 88 ± 21, 175 ± 39 and 270 ± 54 min (mean ± SD), whereas glucose from the HG meal appeared significantly faster at 56 ± 12, 100 ± 25 and 153 ± 39 min (p < 0.001 to 0.003), and resulted in a 50% higher peak appearance (p < 0.001). Higher apparent bioavailability by 15% (p = 0.037) was observed after the LG meal. We documented a 20 min deceleration of dietary mixed carbohydrates compared with dietary glucose for the HG meal and a twofold deceleration for the LG meal. CONCLUSIONS/INTERPRETATION: Absorption patterns may be influenced by glycaemic load and/or meal composition, affecting optimum prandial insulin dosing in type 1 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 1/metabolismo , Carbohidratos de la Dieta/metabolismo , Hiperglucemia/prevención & control , Absorción Intestinal , Comidas , Modelos Biológicos , Adolescente , Adulto , Glucemia/análisis , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/dietoterapia , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Carbohidratos de la Dieta/efectos adversos , Carbohidratos de la Dieta/uso terapéutico , Femenino , Gluconeogénesis , Técnica de Clampeo de la Glucosa , Índice Glucémico , Humanos , Hiperglucemia/etiología , Hipoglucemiantes/sangre , Hipoglucemiantes/uso terapéutico , Técnicas de Dilución del Indicador , Insulina/sangre , Insulina/uso terapéutico , Masculino , Periodo Posprandial , Adulto Joven
10.
Am J Physiol Endocrinol Metab ; 302(12): E1493-501, 2012 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-22454288

RESUMEN

The triple-tracer (TT) dilution technique has been proposed to be the gold standard method to measure postprandial glucose appearance. However, validation against an independent standard has been missing. We addressed this issue and also validated the simpler dual-tracer (DT) technique. Sixteen young subjects with type 1 diabetes (age 19.5 ± 3.8 yr, BMI 23.4 ± 1.5 kg/m(2), HbA(1c) 8.7 ± 1.7%, diabetes duration 9.0 ± 6.9 yr, total daily insulin 0.9 ± 0.2 U·kg(-1)·day(-1), mean ± SD) received a variable intravenous 20% dextrose infusion enriched with [U-(13)C]glucose over 8 h to achieve postprandial-resembling glucose excursions while intravenous insulin was administered to achieve postprandial-resembling levels of plasma insulin. Primed [6,6-(2)H(2)]glucose was infused in a manner that mimicked the expected endogenous glucose production and [U-(13)C; 1,2,3,4,5,6,6-(2)H(7)]glucose was infused in a manner that mimicked the expected glucose appearance from a standard meal. Plasma glucose enrichment was measured by gas chromatography-mass spectrometry. The intravenous dextrose infusion served as an independent standard and was reconstructed using the TT and DT techniques with the two-compartment Radziuk/Mari model and an advanced stochastic computational method. The difference between the infused and reconstructed dextrose profile was similar for the two methods (root mean square error 6.6 ± 1.9 vs. 8.0 ± 3.5 µmol·kg(-1)·min(-1), TT vs. DT, P = NS, paired t-test). The TT technique was more accurate in recovering the overall dextrose infusion (100 ± 9 and 92 ± 12%; P = 0.02). The root mean square error associated with the mean dextrose infusion profile was 2.5 and 3.3 µmol·kg(-1)·min(-1) for the TT and DT techniques, respectively. We conclude that the TT and DT techniques combined with the advanced computational method can measure accurately exogenous glucose appearance. The TT technique tends to outperform slightly the DT technique, but the latter benefits from reduced experimental and computational complexity.


Asunto(s)
Glucosa/metabolismo , Trazadores Radiactivos , Técnica de Dilución de Radioisótopos , Adolescente , Algoritmos , Área Bajo la Curva , Glucemia/metabolismo , Radioisótopos de Carbono/química , Interpretación Estadística de Datos , Deuterio/química , Femenino , Cromatografía de Gases y Espectrometría de Masas , Glucosa/farmacología , Hemoglobina Glucada/análisis , Humanos , Infusiones Intravenosas , Insulina/sangre , Absorción Intestinal , Marcaje Isotópico , Análisis de los Mínimos Cuadrados , Masculino , Reproducibilidad de los Resultados , Procesos Estocásticos , Adulto Joven
11.
Br J Cancer ; 104(5): 746-9, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-21326239

RESUMEN

BACKGROUND: As most children with acute lymphoblastic leukaemia (ALL) achieve long-term survival, minimising late effects of treatment is a priority. Acute lymphoblastic leukaemia survivors treated historically with protocols including cranial irradiation demonstrate increased weight gain. METHODS: We retrospectively studied all 134 patients treated on the MRC/UKALL97 protocol (without cranial irradiation as standard therapy) at a single centre, with 77 inclusions. Height-, weight- and body mass index (BMI) standard-deviation scores (SDS) were recorded at diagnosis and annually until 3 years out (YO) from end of treatment (EoT); changes across time were explored using a univariate model (significance P ≤ 0.001 to account for multiple comparisons). RESULTS: Whole-group height SDS was lower from 1 year into treatment until 2 YO, whereas weight- and BMI-SDS remained higher until 3 YO. In females, height-SDS was lower until EoT, but higher weight- and BMI-SDS persisted until 3 YO. In males, height-SDS was lower at EoT and at 2 YO; differences in BMI-SDS had resolved by 2 YO. By WHO criteria, more patients were overweight or obese at 3 YO than at diagnosis (P=0.01). CONCLUSION: Survivors of childhood ALL, particularly females, exhibit adverse changes in height-, weight- and BMI-SDS, which arise during treatment and persist into follow-up. Patients should be supported with appropriate dietary and lifestyle advice during ALL treatment and follow-up, which may minimise these changes and reduce associated long-term morbidity.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estatura , Índice de Masa Corporal , Peso Corporal , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Sobrevivientes , Adolescente , Niño , Preescolar , Irradiación Craneana , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Obesidad/etiología , Factores Sexuales
12.
Diabet Med ; 27(4): 480-4, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20536523

RESUMEN

AIMS: We assessed an extended interruption of subcutaneous insulin delivery during overnight closed-loop glucose control in children and adolescents with Type 1 diabetes (T1D). METHODS: In seven young subjects with T1D [age 14.2+/-2.1 years, diabetes duration 6.9+/-4.0 years, glycated haemoglobin (HbA1c) 8.0+/-1.5%, body mass index (BMI) 21.4+/-4.0 kg/m2, total daily insulin dose 0.9+/-0.2 units/kg/day; mean+/-sd) participating in overnight closed-loop glucose control studies, insulin delivery was interrupted for at least 90 min on the basis of predicted hypoglycaemia, low prevailing glucose levels or a too-steep decline in glucose levels. RESULTS: Insulin delivery was interrupted for 165 (105, 210) min [median, interquartile range (IQR)]. Plasma glucose was 6.2+/-3.2 mmol/l at the time of interruption and 5.5+/-2.0 mmol/l 105 min later (P=0.15, paired t-test). Plasma glucose declined during the first hour of the interruption at a rate of 0.02+/-0.03 mmol/l per min and reached a nadir of 5.2+/-2.7 mmol/l; 105 min after the interruption, plasma glucose was increasing at a rate of 0.01+/-0.03 mmol/l per min. When insulin delivery restarted, plasma glucose was 6.4+/-2.2 mmol/l and peaked at 7.9+/-2.1 mmol/l in 60 min (P=0.01). Physiological levels of plasma insulin were measured throughout with a nadir of 119+/-78 pmol/l. CONCLUSIONS: A prolonged interruption of insulin delivery during overnight closed-loop glucose control to prevent hypoglycaemia was not associated with an increased risk of hyperglycaemia in young people with T1D.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Hiperglucemia/prevención & control , Hipoglucemiantes/administración & dosificación , Insulina/administración & dosificación , Adolescente , Algoritmos , Niño , Femenino , Humanos , Hipoglucemiantes/uso terapéutico , Infusiones Subcutáneas , Insulina/sangre , Insulina/uso terapéutico , Sistemas de Infusión de Insulina , Masculino , Factores de Tiempo
13.
Diabet Med ; 27(1): 117-22, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20121899

RESUMEN

AIMS: Using compartment modelling, we assessed the time delay between blood glucose and sensor glucose measured by the Guardian RT continuous glucose monitoring system in young subjects with Type 1 diabetes (T1D). METHODS: Twelve children and adolescents with T1D treated by continuous subcutaneous insulin infusion (male/female 7/5; age 13.1 +/- 4.2 years; body mass index 21.9 +/- 4.3 kg/m(2); mean +/- sd) were studied over 19 h in a Clinical Research Facility. Guardian RT was calibrated every 6 h and sensor glucose measured every 5 min. Reference blood glucose was measured every 15 min using a YSI 2300 STAT Plus Analyser. A population compartment model of sensor glucose-blood glucose kinetics was adopted to estimate the time delay, the calibration scale and the calibration shift. RESULTS: The population median of the time delay was 15.8 (interquartile range 15.2, 16.5) min, which was corroborated by correlation analysis between blood glucose and 15-min delayed sensor glucose. The delay has a relatively low intersubject variability, with 95% of individuals predicted to have delays between 10.4 and 24.3 min. Population medians (interquartile range) for the scale and shift are 0.800 (0.777, 0.823) (unitless) and 1.66 (1.47, 1.84) mmol/l, respectively. CONCLUSIONS: In young subjects with T1D, the total time delay associated with the Guardian RT system was approximately 15 min. This is twice that expected on physiological grounds, suggesting a 5- to 10-min delay because of data processing. Delays above 25 min are rarely to be observed.


Asunto(s)
Automonitorización de la Glucosa Sanguínea/instrumentación , Glucemia/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Adolescente , Automonitorización de la Glucosa Sanguínea/normas , Índice de Masa Corporal , Niño , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Factores de Tiempo
14.
Am J Med Genet A ; 152A(2): 340-6, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20082465

RESUMEN

Congenital pancreatic hypoplasia is a rare cause of neonatal diabetes. We report on a series of three patients with pancreatic agenesis and congenital heart defects. All had abdominal scan evidence of pancreatic agenesis. In addition, Patient 1 had a ventricular septal defect, patent ductus arteriosus and pulmonary artery stenosis; Patient 2 had a truncus arteriosus and Patient 3 had tetralogy of Fallot. Two of the three patients have developmental delay. All three patients were isolated cases within the family. Investigations included sequencing of GCK, ABCC8, IPF1, NEUROD1, PTF1A, HNF1B, INS, ISL1, NGN3, HHEX, G6PC2, TCF7L2, SOX4, FOXP3 (Patients 1 and 2), GATA4 and KCNJ11 genes (all three patients), but no mutations were found. Genetic investigation to exclude paternal UPD 6, methylation aberrations and duplications of 6q24 was also negative in all three. 22q11 deletion was excluded in all three patients. Array CGH in Patient (1) showed a approximately 250 kb, paternally inherited duplication of chromosome 12q [arr cgh 12q24.33 (B35:CHR12:131808577-132057649++) pat], not found in the other two patients. Permanent neonatal diabetes mellitus due to pancreatic hypoplasia with congenital heart defects has been reported before and may represent a distinct condition. We discuss this rare association and review previously reported literature.


Asunto(s)
Discapacidades del Desarrollo/diagnóstico , Discapacidades del Desarrollo/genética , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/genética , Páncreas/anomalías , Enfermedades Pancreáticas/complicaciones , Preescolar , Deleción Cromosómica , Cromosomas Humanos Par 12 , Cromosomas Humanos Par 22 , Hibridación Genómica Comparativa , Análisis Mutacional de ADN , Discapacidades del Desarrollo/complicaciones , Ecocardiografía/métodos , Femenino , Cardiopatías Congénitas/complicaciones , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Enfermedades Pancreáticas/diagnóstico
15.
Clin Endocrinol (Oxf) ; 72(2): 155-60, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19508608

RESUMEN

BACKGROUND: Reduced insulin sensitivity and increased fat mass have been reported in children and adults with congenital adrenal hyperplasia (CAH). To understand the potential mechanisms underlying these differences, we assessed insulin sensitivity and body composition in children with classical or nonclassical (late-presenting) CAH compared with normal controls. SUBJECTS AND METHODS: Thirty-seven children with CAH (26 classical and 11 nonclassical) median (range) age 9.4 year (0.5-15.8) were compared with 41 healthy control children age 11.0 year (3.2-17.1). All children had an overnight fasting blood sample and body composition assessed by DEXA. Pubertal children (14 CAH and 19 controls) also had an oral glucose tolerance test. Classical and nonclassical CAH groups were each compared with controls, adjusting for age, gender and pubertal status. Results Classical CAH children had more fat mass than controls (P = 0.03), while nonclassical CAH children had more lean mass (P = 0.006) and higher systolic blood pressure (P = 0.003) than control children. Among pubertal children, nonclassical CAH children had higher mean insulin (0-120 min; P = 0.04), stimulated insulin (0-30 min; P = 0.02), 120 min insulin (P = 0.004) and 120 min glucose levels (P = 0.03) than controls, but no difference in disposition index. DISCUSSION: Greater body fat in classical (early-presenting) CAH children could reflect the effects of lifetime glucocorticoid therapy. In contrast, the greater lean mass and parameters of insulin resistance in nonclassical (late-presenting) CAH children likely indicate the adverse metabolic effects of prolonged postnatal androgen excess.


Asunto(s)
Hiperplasia Suprarrenal Congénita/metabolismo , Composición Corporal/fisiología , Resistencia a la Insulina/fisiología , Adolescente , Hiperplasia Suprarrenal Congénita/sangre , Glucemia/metabolismo , Presión Sanguínea/fisiología , Índice de Masa Corporal , Niño , Preescolar , Ayuno/fisiología , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Lactante , Insulina/metabolismo , Masculino
16.
Arch Dis Child ; 94(11): 868-72, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19542061

RESUMEN

INTRODUCTION: Recent studies in other European countries suggest that the prevalence of congenital cryptorchidism continues to increase. This study aimed to explore the prevalence and natural history of congenital cryptorchidism in a UK centre. METHODS: Between October 2001 and July 2008, 784 male infants were born in the prospective Cambridge Baby Growth Study. 742 infants were examined by trained research nurses at birth; testicular position was assessed using standard techniques. Follow-up assessments were completed at ages 3, 12, 18 and 24 months in 615, 462, 393 and 326 infants, respectively. RESULTS: The prevalence of cryptorchidism at birth was 5.9% (95% CI 4.4% to 7.9%). Congenital cryptorchidism was associated with earlier gestational age (p<0.001), lower birth weight (p<0.001), birth length (p<0.001) and shorter penile length at birth (p<0.0001) compared with other infants, but normal size after age 3 months. The prevalence of cryptorchidism declined to 2.4% at 3 months, but unexpectedly rose again to 6.7% at 12 months as a result of new cases. The cumulative incidence of "acquired cryptorchidism" by age 24 months was 7.0% and these cases had shorter penile length during infancy than other infants (p = 0.003). CONCLUSIONS: The prevalence of congenital cryptorchidism was higher than earlier estimates in UK populations. Furthermore, this study for the first time describes acquired cryptorchidism or "ascending testis" as a common entity in male infants, which is possibly associated with reduced early postnatal androgen activity.


Asunto(s)
Criptorquidismo/epidemiología , Peso al Nacer , Estatura , Preescolar , Criptorquidismo/etiología , Humanos , Lactante , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Estudios Longitudinales , Masculino , Pene/anatomía & histología , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Reino Unido/epidemiología
17.
Diabetologia ; 52(6): 1173-81, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19305965

RESUMEN

AIMS/HYPOTHESIS: The relationship between BP and microalbuminuria in young people with type 1 diabetes is not completely clear. As microalbuminuria is preceded by a gradual rise in albumin excretion within the normal range, we hypothesised that ambulatory BP (ABP) may be closely related to albumin excretion and progression to microalbuminuria. METHODS: ABP monitoring (ABPM) was performed in 509 young people with type 1 diabetes (age median [range]: 15.7 [10.7-22.6] years) followed with annual assessments of three early morning urinary albumin:creatinine ratios (ACRs) and HbA(1c). Systolic BP (SBP) and diastolic BP (DBP) and the nocturnal fall in BP were analysed in relation to ACR. RESULTS: All ABPM variables were significantly related to baseline log(10) ACR (p < 0.001). After the ABPM evaluation, 287 patients were followed for a median of 2.2 (1.0-5.5) years. ABP at baseline was independently related to mean ACR during follow-up. Nineteen initially normoalbuminuric patients developed microalbuminuria after 2.0 (0.2-4.0) years and their baseline daytime DBP was higher than in normoalbuminuric patients (p < 0.001). After adjusting for baseline ACR and HbA(1c), there was an 11% increased risk of microalbuminuria for each 1 mmHg increase in daytime DBP. Forty-eight per cent of patients were non-dippers for SBP and 60% for DBP; however, ACR was not different between dippers and non-dippers and there were no differences in the nocturnal fall in BP between normoalbuminuric and future microalbuminuric patients. CONCLUSIONS/INTERPRETATION: In this cohort of young people with type 1 diabetes, ABP was significantly related to ACR, and daytime DBP was independently associated with progression to microalbuminuria. Increasing albumin excretion, even in the normal range, may be associated with parallel rises in BP.


Asunto(s)
Albúminas/metabolismo , Albuminuria/etiología , Albuminuria/fisiopatología , Presión Sanguínea/fisiología , Diabetes Mellitus Tipo 1/fisiopatología , Diabetes Mellitus Tipo 1/patología , Diabetes Mellitus Tipo 1/orina , Femenino , Humanos , Masculino , Modelos de Riesgos Proporcionales
19.
Pediatr Pulmonol ; 43(4): 354-9, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18286548

RESUMEN

OBJECTIVE: Fluticasone proprionate (FP) is increasingly used to treat very young children with asthma. Its safety in terms of effects on the hypothalamic pituitary axis (HPA) and growth in this age group is uncertain. PATIENTS AND METHODS: Eleven children (median (range) age 10 (5.6-24.3) months) presenting with recurrent wheeze and family history of asthma were studied prospectively for a period of 18 months. Children received daily-inhaled FP 250 microg via a spacer device. No other corticosteroid therapy was administered prior to or during the study. A Short Standard Synacthen Test (SST) (125 microg) was performed pretreatment, and after 6 and 18 months. Weight (Wt), height (Ht), and body mass index (BMI) were measured at 3-6 monthly intervals. RESULTS: Fasting early morning and peak cortisol levels remained within the normal reference range with therapy. There were no changes in Ht SDS, whereas both Wt SDS (baseline 0.05 (-2.17 to 0.52) vs. +18 months 0.68 (-0.5 to 1.36) P < 0.02) and BMI SDS (-0.22 (-1.73 to 0.75) vs. 0.86 (0.03 to 1.99) P < 0.005) increased after 18 months of treatment. CONCLUSION: Daily treatment with inhaled FP 250 microg in young children with asthma appears to have no adverse effects on the HPA or on linear growth, however, treatment is associated with increases in body Wt and BMI in young children.


Asunto(s)
Androstadienos/uso terapéutico , Asma/tratamiento farmacológico , Estatura/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Administración por Inhalación , Androstadienos/administración & dosificación , Androstadienos/efectos adversos , Biomarcadores/sangre , Índice de Masa Corporal , Broncodilatadores/administración & dosificación , Broncodilatadores/efectos adversos , Broncodilatadores/uso terapéutico , Desarrollo Infantil/efectos de los fármacos , Preescolar , Estudios de Cohortes , Femenino , Fluticasona , Humanos , Hidrocortisona/sangre , Lactante , Estudios Longitudinales , Masculino , Estudios Prospectivos , Ruidos Respiratorios/efectos de los fármacos
20.
Arch Dis Child ; 93(2): 147-8, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17768149

RESUMEN

Concordance with growth hormone (GH) therapy in 75 children was objectively assessed using data on GP prescriptions over 12 months. 23% missed >2 injections/week. Lower concordance was associated with longer duration on GH therapy (p<0.005), lack of choice of delivery device (p<0.005) and short prescription durations (p<0.005), and predicted lower height velocities (p<0.05).


Asunto(s)
Trastornos del Crecimiento/tratamiento farmacológico , Hormona de Crecimiento Humana/administración & dosificación , Cooperación del Paciente , Adolescente , Estatura/efectos de los fármacos , Niño , Estudios Transversales , Esquema de Medicación , Monitoreo de Drogas/métodos , Prescripciones de Medicamentos/estadística & datos numéricos , Femenino , Trastornos del Crecimiento/fisiopatología , Hormona de Crecimiento Humana/uso terapéutico , Humanos , Estudios Longitudinales , Masculino , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/uso terapéutico , Resultado del Tratamiento
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