RESUMO
AIM: To find predictors of abnormal retinal vascularisation in moderately to late preterm newborn infants considered to have no risk of developing retinopathy of prematurity. METHODS: Seventy-eight infants (34 girls) were recruited from a longitudinal study of otherwise healthy premature children born at a gestational age of 32 + 0-36 + 6 weeks. Retinal vessel morphology was evaluated at mean postnatal age 7 days. Insulin-like growth factor-I (IGF-I) levels were analysed in umbilical cord blood. RESULTS: Of the 78 infants, 21 (27%) had abnormal retinal vessel morphology; they had significantly lower median (range) birth weight [1850 g, (1190-3260), vs. 2320, (1330-3580), p < 0.0001], shorter birth length [43.0 cm, (38-49), vs. 46.0, (40-50), p < 0.0001] and smaller head circumference [31.0 cm, (27.7-34.0), vs. 32.0, (27.5-36.5), p = 0.003]. They also had significantly lower gestational age [34 + 1 weeks, (32 + 2-35 + 3), vs. 34 + 6, (32 + 2-36 + 6), p = 0.004] and mean ± SD IGF-I levels (24.6 ± 17.0 µg/L vs. 46.7 ± 21.5, p < 0.0001). A higher percentage of these infants were small for gestational age (57.1% vs. 15.8%, p = 0.001), and maternal hypertension/preeclampsia rates were also higher (47.6% vs. 19.3%, p = 0.03). Step-wise logistic regression showed that birth weight was the strongest predictor of abnormal retinal vascularisation (p < 0.0001, odds ratio 0.040, 95% confidence interval 0.007-0.216). CONCLUSION: In this population of moderately to late preterm newborns, birth weight appeared to affect the retinal vascular system.
Assuntos
Peso ao Nascer/fisiologia , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Fator de Crescimento Insulin-Like I/análise , Complicações na Gravidez , Neovascularização Retiniana/etiologia , Vasos Retinianos/patologia , Feminino , Sangue Fetal , Fundo de Olho , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional/sangue , Recém-Nascido Pequeno para a Idade Gestacional/fisiologia , Modelos Logísticos , Estudos Longitudinais , Masculino , Pré-Eclâmpsia , Gravidez , Gravidez em Diabéticas , Neovascularização Retiniana/sangue , Neovascularização Retiniana/patologia , Fatores de Risco , SuéciaRESUMO
CONTEXT: The prevalence of obesity among adolescents has increased and we lack effective treatments. OBJECTIVE: To determine if gastric bypass is safe and effective for an unselected cohort of adolescents with morbid obesity in specialized health care. DESIGN, SETTING AND PATIENTS: Intervention study for 81 adolescents (13-18 years) with a body mass index (BMI) range 36-69 kg m(-2) undergoing laparoscopic gastric bypass surgery in a university hospital setting in Sweden between April 2006 and May 2009. For weight change comparisons, we identified an adult group undergoing gastric bypass surgery (n=81) and an adolescent group (n=81) receiving conventional care. MAIN OUTCOME MEASUREMENTS: Two-year outcome regarding BMI in all groups, and metabolic risk factors and quality of life in the adolescent surgery group. RESULTS: Two-year follow-up rate was 100% in both surgery groups and 73% in the adolescent comparison group. In adolescents undergoing surgery, BMI was 45.5 ± 6.1 (mean ± s.d.) at baseline and 30.2 (confidence interval 29.1-31.3) after 2 years (P<0.001) corresponding to a 32% weight loss and a 76% loss of excess BMI. The 2-year weight loss was 31% in adult surgery patients, whereas 3% weight gain was seen in conventionally treated adolescents. At baseline, hyperinsulinemia (>20 mU l(-1)) was present in 70% of the adolescent surgery patients, which was reduced to 0% at 1 year and 3% at 2 years. Other cardiovascular risk factors were also improved. Two-thirds of adolescents undergoing surgery had a history of psychopathology. Nevertheless, the treatment was generally well tolerated and, overall, quality of life increased significantly. Adverse events were seen in 33% of patients. CONCLUSIONS: Adolescents with severe obesity demonstrated similar weight loss as adults following gastric bypass surgery yet demonstrating high prevalence of psychopathology at baseline. There were associated benefits for health and quality of life. Surgical and psychological challenges during follow-up require careful attention.
Assuntos
Derivação Gástrica/métodos , Laparoscopia/métodos , Obesidade Mórbida/cirurgia , Redução de Peso , Adolescente , Índice de Massa Corporal , Feminino , Seguimentos , Derivação Gástrica/psicologia , Derivação Gástrica/reabilitação , Humanos , Laparoscopia/psicologia , Laparoscopia/reabilitação , Masculino , Obesidade Mórbida/epidemiologia , Obesidade Mórbida/psicologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/psicologia , Complicações Pós-Operatórias/reabilitação , Prevalência , Qualidade de Vida , Fatores de Risco , Suécia/epidemiologia , Resultado do TratamentoRESUMO
AIM: To investigate the development of waist circumference (WC) in preschool children born preterm compared with a population-based reference. BACKGROUND: Children born preterm are reported to be insulin resistant, despite being lean during early childhood. We hypothesize that the mechanism is through increased visceral adiposity. METHODS: Data from 4446 preschool children (2169 girls/2277 boys) born in 2001-2006 from a population-based study were compared with longitudinal measurements of body mass index (BMI) and WC from a cohort of 152 children (64 girls/88 boys) born moderately preterm in 2002-2004 (gestational age, 32-37 weeks). RESULTS: In the preterm children, the mean WC was 2.8 cm larger compared with the reference group (p < 0.001) at 2 years of age but not at 5 years of age. There was no significant difference in the mean BMI at 2 years of age. The preterm group was significantly leaner at 5 years of age, with a mean BMI of 15.13 compared with 15.98 in the reference group (p < 0.001). CONCLUSION: Children born moderately preterm present as lean during early childhood but have an increased waist circumference in infancy, pointing towards a change in fat distribution with more abdominal fat. This may have implications for their metabolic status.
Assuntos
Índice de Massa Corporal , Desenvolvimento Infantil/fisiologia , Recém-Nascido Prematuro/crescimento & desenvolvimento , Circunferência da Cintura , Estudos de Casos e Controles , Pré-Escolar , Feminino , Gráficos de Crescimento , Humanos , Lactente , Recém-Nascido , Modelos Lineares , Estudos Longitudinais , MasculinoRESUMO
AIM: The mode of childbirth delivery can influence the child's future health and the aim of this study was to explore the association between the delivery mode and the prevalence of early childhood caries. METHODS: We searched the PubMed, Google Scholar and Cochrane databases up to September 15, 2020. Two independent reviewers screened the papers for relevance, extracted data and assessed the risk of bias with the Newcastle-Ottawa Scale. We performed a random effects meta-analysis to pool the prevalence of early childhood caries according to the mode of delivery. RESULTS: The authors included 11 studies in the review, comprising 47,688 children with vaginal delivery and 10,994 with caesarean section (C-section). The publication years ranged from 1997 to 2020 and included birth cohorts, cross-sectional, register-based and case-control studies. We assessed three publications with low or moderate risk of bias. The median caries prevalence in the C-section group was 56.4% compared to 45.9% in the vaginal group and this difference was statistically significant (p < 0.05). The pooled overall odds ratio was 1.48 (95% CI 1.07-2.05) indicating a weak but statistically significant trend towards a higher caries occurrence among children delivered with C-section. The certainty of this finding was low due to heterogeneity and inconsistencies across the studies. CONCLUSION: We found a weak but inconsistent association between the mode of delivery and the prevalence of early childhood caries. Further studies based on representative, prospective cohorts reporting a standardized core outcome set are required to answer the research question with higher certainty.
Assuntos
Suscetibilidade à Cárie Dentária , Cárie Dentária , Cesárea , Criança , Pré-Escolar , Estudos Transversais , Cárie Dentária/epidemiologia , Feminino , Humanos , Gravidez , Prevalência , Estudos ProspectivosRESUMO
LAY ABSTRACT: To date, studies using cross-sectional methodologies make up a majority of the literature surrounding children with autism spectrum disorders and participation in physical activity and screen time. Longitudinal studies are needed to examine how physical activity and screen time behaviors co-develop for children with and without an autism spectrum disorder. To address this research gap, this study compared how physical activity and screen time levels changed over time (from 9 to 18 years of age) between youth with autism spectrum disorder and youth with neurotypical development. Data on the levels of moderate-to-vigorous physical activity, light physical activity, television-, and video game-based screen time, collected as a part of the "Growing up in Ireland" study, were compared between youth with autism spectrum disorder and a propensity-matched sample of youth with neurotypical development (n = 88 per group; 176 in total). Robust regression analyses indicated that children with autism spectrum disorder became less active over time compared to children with neurotypical development and that video game screen time also differed significantly between the groups when children were 9 years old. These findings elucidate important disparities present between these groups of children during pivotal developmental times.
Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Adolescente , Criança , Estudos Transversais , Exercício Físico , Humanos , Irlanda/epidemiologia , Tempo de Tela , Fatores de TempoRESUMO
PURPOSE: To study the relationship between the tooth-brushing habits during the preschool ages and caries prevalence at the age of 5 years and to investigate a possible association with the mode of delivery. METHODS: The study population consisted of 336 children that were orally examined at 2, 3 and 5 years. All stages of caries were scored on tooth and surface level. Data on tooth brushing behaviour were collected through semi-structured interviews. RESULTS: At 5 years, the attrition rate was 13.1%. The total caries prevalence (cavitated and non-cavitated lesions) was 18.9%. The vast majority of the parents assisted their child with the brushing and 98% used fluoride toothpaste. The relative risk (RR) for caries was significantly (p < 0.05) increased for "tooth brushing less than twice daily" at two (RR 2.1, 95% CI 1.3-3.3, p < 0.01) and 3 years (RR 3.6, 95% CI 2.0-6.7; p < 0.001). Likewise, reporting "major/minor difficulties to perform tooth brushing" at 2 and 3 years was significantly related to caries development at the age of five (RR 1.5, 95% CI 1.0-2.4, p < 0.05 and RR 2.5, 95% CI 1.4-4.3; p < 0.01). We found no significant association between the tooth brushing habits and the mode of delivery. CONCLUSIONS: Less than twice daily tooth-brushing and difficulties to perform the procedure during the first preschool years were significant determinants of caries prevalence at the age of 5 years. Health professionals should, therefore, give special attention and assist parents to improve and optimize their tooth brushing behaviour during the preschool years.
Assuntos
Cárie Dentária , Escovação Dentária , Criança , Pré-Escolar , Hábitos , Humanos , Prevalência , Estudos ProspectivosRESUMO
PURPOSE: The modified Atkins diet (MAD) is a less restrictive treatment option than the ketogenic diet (KD) for intractable epilepsy and some metabolic conditions. Prolonged KD treatment may decrease bone mineralization and affect linear growth; however, long-term studies of MAD treatment are lacking. This study was designed to assess growth, body composition, and bone mass in children on MAD treatment for 24 months. METHODS: Thirty-eight patients, mean age (SD) 6.1 years (4.8 years), 21 girls, with intractable epilepsy (n = 22), glucose transporter type 1 deficiency syndrome (n = 7), or pyruvate dehydrogenase complex deficiency (n = 9) were included. Body weight, height, body mass index (BMI), bone mass, and laboratory tests (calcium, phosphorus, magnesium, alkaline phosphatase, cholesterol, 25-hydroxyvitamin D, insulin-like growth factor-I and insulin-like growth factor binding protein 3) were assessed at baseline and after 24 months of MAD treatment. RESULTS: Approximately 50% of the patients responded with more than 50% seizure reduction. Weight and height standard deviation score (SDS) were stable over 24 months, whereas median (minimum - maximum) BMI SDS increased from 0.2 (-3.3 to 4.5) to 0.7 (-0.9 to 2.6), p < 0.005. No effects were observed for bone mass (total body, lumbar spine and hip) or fat mass. CONCLUSIONS: The MAD was efficient in reducing seizures, and no negative effect was observed on longitudinal growth or bone mass after MAD treatment for 24 months.
Assuntos
Dieta Rica em Proteínas e Pobre em Carboidratos/métodos , Epilepsia Resistente a Medicamentos/dietoterapia , Adolescente , Densidade Óssea , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Estudos Longitudinais , Masculino , Estudos Prospectivos , Suécia , Resultado do TratamentoRESUMO
CONTEXT: Prenatal growth restriction may affect future fertility in both females and males. Studies have shown that growth-retarded male rats have different sexual behavior and disturbed steroidogenesis. OBJECTIVE: We hypothesized that adult human males born small for gestational age (SGA) have an altered sex hormone profile. DESIGN, SETTING, AND PATIENTS: Twenty-five adult males born SGA with median birth weight -2.2 sd scores (SDS) and birth length -2.4 SDS were studied. Median age was 23.1 yr and final height -0.5 SDS. They were compared with 44 male controls with median age 20.5 yr and final height 0.4 SDS. MAIN OUTCOME MEASURE: The primary outcome before the study started was 17beta-estradiol (E(2)) levels in SGA males. RESULTS: The SGA group showed significantly higher median levels of E(2), 17.9 pg/ml (P < 0.001), and dihydrotestosterone (DHT), 0.543 ng/ml (P < 0.05), compared with controls, 12.6 pg/ml and 0.423 ng/ml, respectively. Testosterone (T) levels did not differ between groups. E(2) to T ratio correlated negatively to birth weight (r = -0.40, P < 0.01) and birth length (r = -0.44, P < 0.001). DHT to T ratio correlated negatively to birth weight (r = -0.51, P < 0.001) and birth length (r = -0.38, P < 0.01). Males born SGA also had significantly higher median levels of inhibin B, 164 pg/ml (P < 0.05), compared with controls, 137 pg/ml. Inhibin B correlated negatively to birth length (r = -0.34, P < 0.01). CONCLUSION: SGA males of normal stature have higher levels of E(2), DHT, and inhibin B than controls, indicating a disturbed steroid synthesis or metabolism. Aromatase activity, calculated as E(2) to T ratio, and 5alpha-reductase activity, calculated as DHT to T ratio, is negatively correlated to size at birth.
Assuntos
Di-Hidrotestosterona/sangue , Estradiol/sangue , Recém-Nascido Pequeno para a Idade Gestacional , Inibinas/sangue , Adiponectina/sangue , Adulto , Estudos de Casos e Controles , Humanos , Recém-Nascido , MasculinoRESUMO
Similarities between lead-induced anemia and a new hereditary erythorenzymopathy involving pyrimidine-specific 5'-nucleotidase prompted studies of the effects of lead on this and other erythrocyte enzymes. In vitro incubations of normal mature erythrocytes demonstrated that significant inhibition of pyrimidine 5'-nucleotidase occurred in the presence of lead at concentrations that had minimal effects on many other erythrocyte enzymes assayed simultaneously. Similarly, subjects with chronic lead intoxication secondary to industrial exposure exhibited substantial and consistent impairment of erythrocyte pyrimidine-5'-nucleotidase activity. Results suggest that lead-induced deficiency of this enzyme in maturing erythroid elements could, if sufficiently severe, result in induction of basophilic stippling and premature erythrocyte hemolysis analogous to that encountered in the genetically induced enzyme-deficiency syndrome.
Assuntos
Eritrócitos/enzimologia , Intoxicação por Chumbo/enzimologia , Nucleotidases/metabolismo , Humanos , Técnicas In Vitro , Chumbo/farmacologia , Nucleotidases/deficiência , RibonucleotídeosRESUMO
BACKGROUND: Laparoscopic Roux-en-Y gastric bypass (RYGB) causes changes in body composition and bone metabolism, yet little is known about effects in adolescents. OBJECTIVES: The objective of this study was to report dual-energy X-ray absorptiometry measures and serum bone markers, hypothesizing that bone turnover increases after surgery. METHODS: Inclusion criteria included the following: age 13-18 years and body mass index (BMI) >35 kg/m2 . Seventy-two adolescents (22 boys; mean age 16.5 years; BMI 44.8 kg/m2 ) undergoing RYGB underwent dual-energy X-ray absorptiometry and serum bone marker analyses preoperatively and annually for 2 years. RESULTS: Mean BMI reduction at 2 years was 15.1 kg/m2 . Body composition changes included a reduction in fat mass (51.8% to 39.6%, p < 0.001) and relative increase in lean mass (47.0% to 58.1%, p < 0.001). In contrast to previous studies in adults, adolescent boys lost a greater percentage of their body fat than girls (-17.3% vs. -9.5%, p < 0.001). Individual bone mineral density Z-scores (BMD-Z) at baseline were within or above the normal range. The mean (SD) BMD-Z was 2.02 (1.2) at baseline, decreasing to 0.52 (1.19) at 2 years. Higher concentrations of serum CTX (p < 0.001) and osteocalcin (p < 0.001) were observed in boys throughout the study period. Levels rose in the first year, before decreasing modestly in the second. Levels of serum markers of bone synthesis and resorption were higher in boys, whose skeletal maturity occurs later than girls'. CONCLUSIONS: Differences in body fat and lean mass proportions were observed according to sex following RYGB. Bone turnover increased, and BMD decreased to levels approaching a norm for age. Long-term outcome will determine the clinical relevance.
Assuntos
Composição Corporal , Densidade Óssea , Derivação Gástrica/efeitos adversos , Obesidade Mórbida/cirurgia , Absorciometria de Fóton/métodos , Adolescente , Biomarcadores/sangue , Índice de Massa Corporal , Feminino , Seguimentos , Humanos , Masculino , Redução de PesoRESUMO
To provide basic information on the normal functioning of the hypothalamus-pituitary-adrenal axis in relation to pubertal development, growth (weight and height), body composition, and gender and to obtain reference data for serum cortisol concentrations in children, we investigated the basal circadian rhythm of serum cortisol in a group of 235 healthy children (162 boys and 73 girls). The age range was between 2.2-18.5 yr. Serum cortisol was analyzed from venous blood samples taken at 1400, 1800, 2200, 0200, 0400, 0600, and 1000 h. No evidence was found for differences in temporal placement or level of the circadian cortisol rhythm in relation to age, growth, or body composition. However, we found a broad range of cortisol levels in a healthy population, with individual mean diurnal levels ranging from 100-510 nmol/L. Regardless of high or low mean diurnal cortisol levels, repeated measurements within and between pubertal stages indicated that an individual remains in his or her cortisol range throughout pubertal development. In conclusion, the present study shows that 1) serum cortisol levels do not correlate with either age or gender; 2) there is a large and significant interindividual variability in endogenous mean diurnal cortisol levels; and 3) despite this variability between individuals, there is no correlation between cortisol levels and either body composition or growth rate. This suggests that the variability in cortisol levels is an expression of normal homeostasis rather than pathology.
Assuntos
Envelhecimento/sangue , Composição Corporal , Desenvolvimento Infantil , Ritmo Circadiano , Hidrocortisona/sangue , Puberdade , Caracteres Sexuais , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Valores de ReferênciaRESUMO
Events occurring early in life or prenatally are able to play important roles in the pathogenesis of diseases in adult life. Different sorts of stress or hormonal influences, during particular periods of pregnancy, may result in persisting or transient changes in physiology. Glucocorticoids are used for the treatment of a variety of diseases, to promote organ maturation and to prevent preterm delivery. Glucocorticoids are also known to affect skeletal growth and adult bone metabolism. The aim of the present study was to investigate whether exposure to dexamethasone (Dex) during fetal life has any effect on skeletal growth and/or bone mineral density in adult rat offspring. Pregnant rats were given injections of either Dex (100 micro g/kg) or vehicle on days 9, 11 and 13 of gestation. Dex-exposed male but not female rat offspring showed transient increases in crown-rump length and tibia and femur lengths at 3-6 weeks of age. In contrast, the cortical bone dimensions were altered in 12-week-old female but not male Dex-exposed offspring. The areal bone mineral densities of the long bones and the spine, as determined by dual X-ray absorptiometry, and trabecular as well as cortical volumetric bone mineral density, as measured using peripheral quantitative computerized tomography, were unchanged in both male and female Dex-exposed offspring. In conclusion, prenatal Dex exposure affects skeletal growth in a gender-specific manner, while the mineralization of bones is unaffected in both male and female offspring.
Assuntos
Densidade Óssea/efeitos dos fármacos , Desenvolvimento Ósseo/efeitos dos fármacos , Dexametasona/efeitos adversos , Glucocorticoides/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Absorciometria de Fóton , Animais , Feminino , Fêmur/efeitos dos fármacos , Fêmur/crescimento & desenvolvimento , Fêmur/fisiologia , Idade Gestacional , Gravidez , Distribuição Aleatória , Ratos , Ratos Wistar , Sexo , Tíbia/efeitos dos fármacos , Tíbia/crescimento & desenvolvimento , Tíbia/fisiologia , Tomografia Computadorizada por Raios XRESUMO
The product of the obese (ob) gene, leptin, is an adipocyte-derived hormone that is involved in the regulation of appetite and body weight. This study was undertaken in order to describe the basal serum levels of leptin in prepubertal short children born small for gestational age (SGA) and their relationship with growth parameters, before and during growth hormone (GH) treatment. Eighty-nine prepubertal short children (66 boys, 23 girls; height standard deviation score (SDS), -5.4 to -2.0; age, 2.0 to 12.8 years) born SGA, 12 of whom (9 boys, 3 girls) had signs of Silver-Russell syndrome, were included in the study. Serum leptin concentrations were measured by radioimmunoassay. Leptin levels in the children born SGA were compared with those in a reference group of 109 prepubertal healthy children born at an appropriate size for gestational age (AGA). The mean (S.D.) change in height SDS was 0.11 (0.22) during the year before the start of GH therapy (0.1 IU/kg/day) and increased to 0.82 (0.44) during the first year (P < 0.001) and to 1.28 (0.59) during the 2-year period of GH therapy (P < 0.001). The children born SGA were significantly leaner than the reference group. An inverse correlation was found between leptin and chronological age in the SGA group (r = -0.31, P < 0.01). The mean serum level of leptin in the children born SGA who were older than 5.5 years of age was 2.8 micrograms/l which was significantly lower than the mean value of 3.7 micrograms/l found in the children born AGA of the same age range. The difference remained after adjustment of leptin levels for sex, age, body mass index (BMI) and weight-for-height SDS (WHSDSSDS). Leptin correlated with WHSDSSDS (r = 0.32, P < 0.001) and BMI (r = 0.36, P < 0.01) in the reference population, but not in the SGA group. No correlation was found between leptin and spontaneous 24-h GH secretion, insulin-like growth factor (IGF)-I or IGF-binding protein-3 levels, or with fasting insulin or cortisol levels. Leptin levels at the start of GH treatment were correlated with the growth response over both 1 year (r = 0.46, P < 0.001) and 2 years (r = 0.51, P < 0.001) of GH therapy. Using multiple regression analysis, models including leptin levels at the start of GH therapy could explain 51% of the variance in the growth response after 1 year and 44% after 2 years of GH treatment. In conclusion, serum leptin levels are reduced in short children born SGA and are inversely correlated with chronological age. Leptin concentrations correlate with the growth response to GH treatment and might be used as a marker for predicting the growth response to GH treatment.
Assuntos
Desenvolvimento Infantil/efeitos dos fármacos , Hormônio do Crescimento/uso terapêutico , Hormônio do Crescimento Humano/uso terapêutico , Recém-Nascido Pequeno para a Idade Gestacional/sangue , Proteínas/análise , Envelhecimento/sangue , Estatura , Índice de Massa Corporal , Peso Corporal , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Hormônios/sangue , Humanos , Leptina , Masculino , Concentração Osmolar , Valores de Referência , Caracteres SexuaisRESUMO
OBJECTIVE: To investigate the levels and diurnal rhythm of serum leptin in healthy children, and to investigate the association between leptin levels and sex steroids. METHODS: Four girls and four boys, all healthy volunteers, were followed longitudinally throughout puberty. Their chronological ages ranged from 8.7 to 19.5 years, and body composition, expressed as weight-for-height standard deviation scores (SDS), ranged between -1.7 and +2.4. Serum leptin, oestradiol and testosterone concentrations were measured by radioimmunoassay at 1000, 1400, 1800, 2200, 0200 and 0600 h. RESULTS: In all girls and boys, both prepubertally and during pubertal development, serum leptin levels increased during the night, with no difference in relative peak amplitude. In boys, the leptin concentrations increased until the initiation of puberty and then declined, whereas in girls, the concentrations increased throughout puberty. The inter-individual variation in mean leptin levels among girls decreased to 11% at the time of menarche. A positive correlation was found for both oestradiol and testosterone versus leptin in girls throughout puberty (r=0.64 and r=0.71 respectively, P<0.001). A negative correlation was found between leptin and testosterone in boys in mid- and late puberty (r=-0.66, P<0.01). No correlation was found between oestradiol and leptin in boys or between testosterone and leptin in pre- and early pubertal boys. CONCLUSION: Serum leptin concentrations show diurnal variation throughout pubertal development in both girls and boys. The changes in leptin levels during puberty follow a gender-specific pattern, probably due to an influence of sex steroids on leptin production.
Assuntos
Ritmo Circadiano/fisiologia , Leptina/sangue , Puberdade/sangue , Adolescente , Adulto , Criança , Estradiol/sangue , Feminino , Humanos , Leptina/metabolismo , Estudos Longitudinais , Masculino , Fatores Sexuais , Estatísticas não Paramétricas , Testosterona/sangueRESUMO
OBJECTIVE: Nutritional status is an important determinant of growth, and previous studies have indicated that this is due, at least in part, to an increased target-tissue sensitivity to GH. An attractive candidate for mediating this effect is leptin, a hormone secreted by the adipose tissue. The aim of this study was to investigate if there was a connection between GH-binding protein (GHBP) and leptin. DESIGN AND METHODS: We investigated the relationship between serum levels of leptin and those of GHBP in 229 prepubertal children. These included 107 healthy children with normal GH secretion, 55 GH-deficient (GHD) children and 55 children born small for gestational age (SGA) sampled on one occasion for GHBP and leptin, and 12 healthy children followed longitudinally at monthly interval for 1 year. RESULTS: In the healthy children and in those born SGA, the serum concentration of GHBP was positively correlated with that of leptin (r = 0.65, P < 0.001; r = 0.74, P < 0.001 respectively). There was no correlation between GHBP and leptin in the group of children with GHD (r = 0.27, not significant). This means that leptin alone explained 42% of the variation of GHBP in the healthy group and 55% in the SGA group. The correlation remained after adjustment for body mass index and age in the healthy children (r = 0.57, P < 0.0001, r2 = 0.33) and for children born SGA (r = 0.74, P < 0.0001, r2 = 0.55). There was a positive correlation between the intra-individual monthly changes in GHBP and changes in leptin respectively, in the 12 healthy children followed longitudinally, the mean of the correlation coefficients was 0.38 (median = 0.29; range 0.03 to 0.86; P < 0.05). CONCLUSIONS: There was a highly significant correlation between serum levels of leptin and those of GHBP, except in children with GHD. The possibility that leptin could mediate the effects of body fat mass on GH sensitivity, therefore, merits further investigation.
Assuntos
Proteínas de Transporte/sangue , Proteínas/metabolismo , Adolescente , Índice de Massa Corporal , Criança , Pré-Escolar , Estudos Transversais , Feminino , Hormônio do Crescimento Humano/deficiência , Hormônio do Crescimento Humano/metabolismo , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Leptina , Estudos Longitudinais , Masculino , Puberdade , Valores de ReferênciaRESUMO
The lomefloxacin antibacterial activity was assessed against 442 clinical isolates of common bacterial pathogens and compared to the previously studied activity of ciprofloxacin, imipenem, norfloxacin, and other commonly used antibacterials. Lomefloxacin showed activity against the species of Enterobacteriaceae tested at a concentration equal to or below that of the most commonly used agents. Activity was lower against Pseudomonas species as well as most Gram-positive isolates tested with the exception of Staphylococcus aureus. Streptococcal strains were least susceptible. The results of this study support previous reports of excellent antimicrobial activity for lomefloxacin, especially against Gram-negative organisms.
Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Fluoroquinolonas , Quinolonas , 4-Quinolonas , Bactérias/isolamento & purificação , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Streptococcus/efeitos dos fármacos , Streptococcus/isolamento & purificaçãoRESUMO
Diatomaceous earth is a noncrystalline form of silica; in processing, calcining leads to formation of cristobalite, a form of crystalline silica. Four hundred ninety-two currently employed diatomaceous earth workers in a large mine and processing facility had chest radiographs performed and interpreted by the International Labour Office (ILO) system. Two hundred sixty-seven subjects underwent spirometry testing. Exposure indices for total dust (largely diatomaceous earth) and cristobalite were reconstructed for each individual based upon personnel records. Analysis demonstrated the following prevalences of radiographic findings: 5% had ILO scores > or = 1/0, and 25% had scores of 0/1 or higher. Regression analyses showed that there was a relationship between both total cristobalite exposure and total dust (largely diatomaceous earth) exposure and the ILO score. Radiographic patterns are not typical of those of classic silicosis. Linear regression analyses for forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio did not demonstrate a relationship between cumulative exposure and lung function. Such analyses were performed using all subjects and stratified by smoking status. There were differences in spirometric data according to radiographic ILO category, but the results were inconsistent and did not permit determining if physiologic changes are associated with radiographic change or if this is due to confounding. Overall, the study suggests that diatomaceous earth pneumoconiosis (radiographically defined) is an entity distinct from silicosis. Recent exposure levels may produce radiographic abnormalities but do not lead to demonstrable physiologic effect. The prevalence of the disorder has diminished markedly in response to modern dust control measures. Ongoing medical surveillance is recommended in workers with potential exposure to significant quantity of material.
Assuntos
Terra de Diatomáceas/efeitos adversos , Mineração , Exposição Ocupacional/efeitos adversos , Pneumoconiose/diagnóstico , Adulto , Distribuição por Idade , California/epidemiologia , Diagnóstico Diferencial , Feminino , Inquéritos Epidemiológicos , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Pneumoconiose/epidemiologia , Pneumoconiose/etiologia , Prevalência , Testes de Função Respiratória , Fatores de Risco , Silicose/diagnóstico , Fumar/epidemiologia , EspirometriaRESUMO
The severity of toxic effects on nearly fully-grown birds from an organophosphorus insecticide (isofenphos) was shown to be affected by the tested birds' previous diet as juveniles. Subadult grey partridges (Perdix perdix), with an insect-poor diet as juveniles, were severely affected by the insecticide, whereas birds fed an insect-rich diet as juveniles showed no signs of poisoning after feeding on isofenphos-treated seeds.
RESUMO
An extract from red-wine grape fermentation, ANOX has been developed as a source of red-wine polyphenols, which are thought to inhibit several of the pathogenic pathways that lead to cardiovascular disease. New data indicate that this extract has a significantly greater effect than either red wine or red-wine powder on the inhibition of platelet aggregation in vitro. Based on this data, about 300 - 500 mg of the extract is equivalent to the daily dose of red-wine polyphenols that appears to protect against cardiovascular disease. The possible synergistic effect of red-wine polyphenols with vitamin C, their vasorelaxing activity and their possible role in preventing over-crosslinking of connective tissues (premature ageing) are considered. The extract contains standardized amounts of the whole spectrum of polyphenolic compounds found in red wine and may provide a valuable reference substance in clinical investigations of the physiological actions of plant polyphenols; its potential use in functional nutrition and preventive medicine is also discussed.
Assuntos
Doenças Cardiovasculares/prevenção & controle , Flavonoides , Fenóis/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Agregação Plaquetária/efeitos dos fármacos , Polímeros/uso terapêutico , Vinho , Animais , Humanos , PolifenóisRESUMO
Thirty-four lead smelter workers with excessive lead absorption were evaluated and followed. Abdominal pain was present in 27 patients. Fifteen patients who had left the site of lead exposure experienced persisting abdominal pain for as long as 29 months; some of these demonstrated acceptable levels of lead in blood. There is no correlation between lead levels and persisting pain. Twenty-three patients developed abdominal pain with blood lead lower than 80 microgram/100 ml while working. Four out of 15 patients with persisting abdominal pain had blood lead between 40 and 60 microgram/100 ml while working. Typical lead-induced abdominal pain is a sensitive symptom of intoxication and may be a criterion for removal from exposure regardless of blood lead levels.