Craniofacial catch-up growth in intrauterine growth retarded rats following postnatal nutritional rehabilitation.

PURPOSE: The aim of the study was to analyze the effect of postnatal nutritional rehabilitation on the craniofacial growth in rats with intrauterine growth retardation (IUGR). MATERIALS AND METHODS: Wistar rats were assigned to one of the following groups: control, Sham-operated, and IUGR. The IUGR was produced by uterine vessels bending (day 14 of pregnancy). At days 1, 21, 42, 63, and 84 of postnatal life, each animal was X-rayed, and neural and facial length, width and height were measured. Volumetric and morphometric indices were calculated. RESULTS: The decreased maternal-fetal blood flow during the last-third of the gestation period modified cranial size and shape of both sexes at birth. DISCUSSION: Postnatal nutritional rehabilitation is not fully sufficient to reverse the prenatal growth retardation. There are specific responses depending on the sex and the age of the IUGR pups. Regardless of the changes in size, the shape is not modified during all the postnatal period.

Linear growth in children with congenital hypothyroidism detected by neonatal screening and treated early: a longitudinal study.

We performed a longitudinal study of a cohort of 74 children with congenital hypothyroidism (CH) detected by neonatal screening (Buenos Aires Province, Argentina) up to the age of 3 years old, in order to study linear growth and the relationship with the severity of CH at diagnosis. The mean age at diagnosis and the start of the treatment was 16.9 +/- 5.2 days. The patients were divided into group 1--severe CH (pretreatment T4 level <4 microg/dl) (n = 47)--and group 2--less severe CH (pretreatment T4 level > or = 4 microg/dl) (n = 27). Patients with CH treated early showed a sexually dimorphic pattern of growth: girls tended to be longer than boys at all ages. Boys showed some delay of growth during the first year. No difference was found in linear growth between the two groups (more/less severe CH). Height was normal in both sexes at the age of 3 years old.

Validity of the use of a few hand-wrist bones for assessing bone age.

Bone age is widely used as an osseous maturation method to assess biological development in clinical and auxological studies. Numerical methods for calculating bone age have better replicability; however, they require a wide data manipulation. The aim of this study was to evaluate the accuracy of bone age estimation by using just a few ossification centers. In 205 hand and wrist radiographs of children and adolescents, aged 0.9-17.4 years old (111 males and 94 females), bone age was determined by two trained observers employing the five-bone (B5) and the TW2 methods. To compare the results of the two methods, the mean differences by age and sex were tested by the Mann-Whitney test. The relationship of the bone age distribution estimated by B5 and TW2 was calculated and the mean of the bone age determined by the two methods was plotted by age and by differences between bone age calculated by the two methods +/- 2 SD. The bone age determined by B5 was between 1.2 and 16.8, and by TW2 was between 1.2 and 18.0 years. The mean differences between B5 and TW2 (-0.06 +/- 0.6) were not significant (p > 0.05). The distribution of mean differences by age and method demonstrated that all deviations were encompassed into +/- 2 SD with no particular bias. In general terms, a good agreement was obtained between these two methods.

Skeletal maturation in intrauterine growth-retarded rats treated with growth hormone.

The objective of this study was to analyse the effects of intrauterine growth retardation (IUGR) and growth hormone (Gh) therapy on skeletal maturation in growth retarded rats. One-hundred and thirty-five rats constituted the groups: Control (C), Sham-operated (SH), IUGR and IUGR+Gh: injected with Genotropin 3.0 mg/kg/day) from 21 to 60 days of age. SH was injected only with saline solution. The thickness of tibial cartilage was assessed on X-ray at the ages 1, 21, 42, 63 and 84 days and categorised according to three levels. L1: maximal thickness, L2: reduction of 50% and L3: absence. The percentual differences between frequencies for each level were compared and clustered by simple ligation in Euclidean distance. The results lead to us to conclude that skeletal maturation does not appear to be modified by IUGR, while it is accelerated by growth hormone in growth-retarded rats.

Body weight recovery in intrauterine growth-retarded rats treated with growth hormone.

The aim of this work was to analyze the action of growth hormone (GH) on postnatal body weight recovery in intrauterine growth-retarded (IUGR) rats. Wistar rats were assigned to three groups: 1) control; 2) IUGR and 3) sham-operated. Uterine vessels of dams in the IUGR group were partially bent on the 14th day of pregnancy. At weaning, some IUGR pups were randomly selected and injected with GH (3 mg/kg/day), up to the 60th day. A standard diet ad libitum was available to mothers and offspring. The animals were weighed and food intake was recorded weekly. The weight gained velocity and relative food intake (RFI) was calculated. IUGR animals showed significant lower body weights than the control group. GH treatment allowed body weight recovery in IUGR rats. In females, body weight increased 14 days before males, and the former had greater RFI values. In conclusion, our results indicated differences in sexual responses to GH treatment. There is a need for more research on the mechanisms involved in that sexual difference.

Effects of bilateral uterine vessel ligation on skeletal growth in rats.

The aim of the present study was to assess the catch-up growth in the postcranial skeleton of intrauterine growth retarded (IUGR) rats. Male and female Wistar rats were assigned to one of the following groups: controls, sham-operated, IUGR. The IUGR was produced by uterine vessels bending (day 14th of pregnancy). Trunk, pelvis, femur and humerus were measured on Rx of each animal, from I to 84 days of age. Data were processed by repeated analysis of variance and LSD post hoc test. The reduced placental blood flow disturbed the skeletal growth in pups, with the axial skeleton relatively more affected than the bones of the extremities. The catch up only took place in femur length of both sexes. The widths of long bones remained significantly retarded. We concluded that nutritional rehabilitation during the postnatal period might not be enough to allow a complete growth recovery.

[Relationship between the nutritional status of pregnant adolescents and fetal growth]. / Relación entre el estado nutricional de embarazadas adolescentes y el crecimiento fetal.

In order to identify differences in growth and nutritional status between early (up to 17 years old) and late (17 to 19 years old) adolescent mothers during pregnancy and to measure the risk to have an intrauterine growth retardation (IGR: birthweight < 10 degrees percentile), a retrospective longitudinal anthropometric study was carried out in 300 adolescent pregnancies. Nutritional status was estimated according to the body mass index (height/weight2)--measured during the first (< 20 weeks) and last (> 33 weeks) prenatal control--and by the weight gain during pregnancy. When a mother had a weight gain < 25 degrees percentile she was considered at risk to have an IGR. Neonatal anthropometry included birthweight, recumbent length, cephalic perimeter and body mass index. Comparison between both groups of mothers was performed by one way ANOVA and Mantel-Haenszel stratified procedure. Odds-ratio was also calculated. Results showed no statistically significant differences in growth between both early and late adolescent pregnancies and between both groups of newborns. When a mother had a weight gain < 25 degrees percentile the relative risk to have an IGR increase up to three times (O.R = 2.71 I.C. 95%: 1.31/6.45). There were highly significant differences in growth between newborns from mothers at risk and from mothers not at risk (p < 0.01). The study showed that the risk to have an IGR is significantly related to nutritional status and not to age itself in adolescent pregnancies.

[Prediction of final height in girls with Turner syndrome treated with growth hormone]. / Predicción de la estatura final en niñas con síndrome de Turner tratadas con hormona de crecimiento.

Treatment with growth hormone (GH) in girls with Turner syndrome (TS) would improve growth velocity (GV) and final height (FH) prediction. A total of 21 girls with TS treated with GH for 1 (n = 21), 2 (n = 18) and 3 years (n = 10) were studied. At the onset of GH treatment, the mean chronological age was 11.6 +/- 2.6 years and the mean bone age was 9.7 +/- 2.4 years. The mean height SDS was: -0.04 +/- 1.0 at the beginning, 0.4 +/- 1.0 at 1st year, 0.9 +/- 1.1 at 2nd year and 1.25 +/- 0.56 at 3rd year of treatment (p = 0.0001, p < 0.0001 and p < 0.05 respectively). The mean GV SDS was 1.6 +/- 1.8 at the beginning, 2.5 +/- 1.7 at 1st year, 3.8 +/- 2.9 at 2nd year and 2.2 +/- 2.0 at 3rd year (p = 0.01, p = 0.04 and p = 0.29 respectively). The FH prediction by Bayley-Pinneau method was: 142.8 +/- 5.2 cm at the beginning, 143.8 +/- 6.0 at 1st year, 146.0 +/- 5.9 at 2nd year and 145.6 +/- 6.4 at 3rd year (p = 0.026, p = 0.05 y p = 0.87 respectively). The mean ending height treatment (EH), in 8 patients, was 145.1 cm +/- 6.7. In conclusion, 1) studied patients showed systematic bone age delay at the beginning of GH treatment; 2) during the treatment, GV increment and improvement in relative heights and in FH prediction were observed; 3) the EH, nearest to the FH prediction, previously made at 3rd year of treatment, was 7.2 cm higher than mean FH's for Argentinean girls with TS without GH treatment.

[Effect of estrogen therapy on the growth of Turner syndrome in girls treated with growth hormone]. / Efecto del tratamiento con estrógenos sobre el crecimiento en niñas con sindrome de Turner tratadas con hormona de crecimiento.

Two groups of patients with Turner Syndrome (TS) were studied to analyse the effect of estrogens on their growth. Group 1 (G1): 14 patients treated with growth hormone (GH) who started estrogens (SO) (Premarín) at 15.3 +/- 0.9 years old. Group 2 (G2): 10 girls not treated with GH who started Premarín at 14.3 +/- 2.3 years old. Height SDS improvement in periods of time of GH and GH plus estrogen treatment was evaluated and compared between both groups. The gain in stature during estrogen therapy (final height-projected height at SO) was calculated. In G1 multiple regression was used to examine factors influencing the gain in stature during GH treatment (final height-projected height at the start of GH): bone age at the SO, chronological age at the SO and the time of GH treatment prior to SO. In G1 the height SDS improvement was 0.43 +/- 0.11 cm during GH treatment and 0.59 +/- 0.18 cm during GH plus oestrogens (p = 0.064). The height SDS improvement during estrogen therapy in G2 was 0.14 +/- 0.19 cm, smaller than in G1 (p < 0.001). Gain in stature during estrogen therapy was 5.3 +/- 1.8 cm in G1 and -0.6 +/- 4.2 cm in G2 (p = 0.001). In G1 the time of GH treatment prior to SO was the strongest predictor of the gain in stature during GH treatment (r = 0.89).

[Brachial indicators of fat and muscle in schoolchildren of a rural community according to social groups (General Lavalle, Buenos Aires, Argentina)]. / Indicadores braquiales de grasa y músculo de escolares de una comunidad rural según el grupo social (General Lavalle, Buenos Aires, Argentina).

In order to determinate the body composition in a schoolchildren rural community--General Lavalle, Buenos Aires, Argentina--the arm circumference (AC) and the triceps skinfold (TS) growth were studied by cross-sectionally methods. From those measurements the arm muscle area was calculated. All the data were transformed to "Z" scores. The sample was divided into seven social groups according to the educational and occupational levels of parents. Statistics analysis of variance (ANOVA test) and Tukey test were performed. Statistically significant differences in AC an TS among the social groups were observed (p < 0.001). Two different patterns of brachial composition were observed according to the social group. This composition was different with respect to urban populations. Our findings suggest an environmental adaptation by growth.

[Relationships between body mass index during pregnancy in adolescent and adult women, anthropometric indicators of fetal growth and intrauterine growth retardation. La Costa, Argentina, 1999]. / Relación entre el índice de masa corporal durante la gestación en embarazadas adolescentes y adultas, indicadores antropométricos de crecimiento fetal y retardo de crecimiento intrauterino. La Costa, Argentina, 1999.

UNLABELLED: Body mass index (BMI) has been employed as an epidemiologic predictor of fetal growth. But most of the studies are focused on BMI values for non pregnancy women, while BMI varies according to gestational age. On the other hand, adolescence has been considered as a risk factor for intrauterine growth retardation (IUGR: birthweight for gestational age < 10th. centile). The aims of this study were: 1) to identify the distribution for weight, height and BMI in adolescent and adult pregnancies, 2) to measure the association between maternal BMI and fetal growth and 3) to evaluate the relative risk to have an intrauterine growth retardation (IUGR) according to maternal BMI. 2409 pregnancies and their newborns were studied. Maternal height and weight were measured and BMI by gestational age was calculated by trimesters of gestation. Birthweight, recumbent length, cephalic perimeter, BMI and weight by gestational age were determined in the newborns. Z score by gestational age were calculated in each pregnant woman taken into account the cut of point of BMI of -1 standard deviation. There were highly statistically significants differences in both body size and body composition between adolescent and adult mothers and in their newborns. The newborns from mothers with BMI under -1 standard deviation were smaller and the relative risk to have an IUGR was double for newborns whose mothers had BMI under -1 standard deviation. CONCLUSIONS: 1--Both body size and composition values differs between newborns from mothers under or above the cut off point of -1SD of BMI and 2--The risk to have an IUGR was double in pregnancies under -1 SD of BMI, independently to the age of the mother.

[Growth and sex dimorphism in school children according to their father's occupation]. / Crecimiento y dimorfismo sexual de escolares según la ocupación laboral paterna.

A cross-sectional morphometric study on 569 school children from the city of San Clemente del Tuyú (Buenos Aires, Argentina) has been performed. The sample was subdivided into 28 subgroups according to the age range (7-13 years old), sex, and occupational status -low or high- of the fathers. Body weight, height, sitting height, and head and arm circumferences were measured. Statistics of analysis of variance (ANOVA) and Tukey test for unequal sample sizes were performed at each stage of age. Both males and females belonging to the lower social status showed a general decrement in growth: shortening in leg length was evident. Since the girls from both occupational status showed -in general terms-hypothesis of "better canalization of the females" has been corroborated by the present work.

[Training and standardization of personnel for performing an anthropometric study in school children]. / Treinamento e padronização do pessoal para a realização de um estudo antropométrico em escolares.

In order to avoid ponderable errors among the anthropometrists working in a project of school health, a training model was developed. Four subjects were trained (A, B, C and D). Significant and highly significant differences in the reading of skinfold (F = 5.15) and height (F = 8.17) were observed only with subject C. These differences were not present in the last reading, which means that there was an improvement in the determinations. Analyzing all subjects, it was possible to verify that subject D presented significant and highly significant differences with the other subjects (skin fold delta 5% - 6.16 and delta 1% = 8.08, arm circumference delta 5% = 0.50 and delta 1% = 0.67, height delta 5% = 0.27). This subject, however, had the lowest variability in the readings, which means that this systematic error was personal. The method that was applied is useful in the training and standardization of anthropometrists, and for the detection of those subjects who present systematic errors.

[Growth in school children of Villa IAPI (Quilmes, Buenos Aires, Argentina)]. / Crecimiento en escolares de Villa IAPI (Quilmes, Buenos Aires, Argentina).

Growth in schoolchildren of Villa IAPI--a poor neighborhood placed near Buenos Aires (Argentina)--were cross-sectionally studied. Six hundred and forty five--291 males and 354 females--children from six to twelve years old were weighed (W), and the standing (StH) and sitting (SiH) heights, the head (HC) and the arm (AC) circumferences, and the triceps (TS) an the subscapular (SS) skinfolds were measured. The muscular braquial circumference (MC), and the length of the inferior segment of the body (IS) were also calculated. All of the measurements were transformed to "z" scores. It was observed that in all cases--except for 11 year-old females--both W and StH were diminished. This trend was stronger in males than in females. Both SiH an HC did not show differences with respect to local growth standards. Skinfold values however, were always greater in Villa IAPI children--except SS in 9 to 12 year-old males, and in 12 year-old females--than those of normal standards, Such differential growth pattern suggests that two joined strategies--for protection and adaption to unbalanced environment--actually acted in the Villa IAPI population.

Skeletal maturity of the hand and wrist of healthy Argentinian children aged 4-12 years, assessed by the TWII method.

One previously trained observer assessed skeletal maturity in a representative sample of 388 and 387 healthy girls and boys respectively from La Plata city, a predominantly university and administrative urban centre in Argentina. The staging system used was TWII and the scores were calculated from three sources: British, Spanish and Italian standards. Our sample showed a marked advancement in bone age with regard to chronological age when using British standards and, to a lesser extent, when applying the Spanish standards. Local mean bone ages were very similar to chronological ages when the Italian scores were used. Second-degree polynomials were adjusted to log10 scores for boys and girls, in order to obtain local values for bone age (BA) transformations. The same staging system should be used in clinical work in Argentina, with the corresponding changes in BA transformatons. A marked advancement of carpal BAs with regard to RUS BAs was found, from age 5 onwards, in both sexes. Mean differences and SD of RUS-minus-carpal BA were 1.28, SD 1.08 and 1.18, SD 1.09 years for girls and boys respectively. These differences have not been described before, and require further investigation.

Study of growth in rural school children from Buenos Aires, Argentina using upper arm muscle area by height and other anthropometric dimensions of body composition.

The primary objective was to compare growth and body composition in an infantile rural population by means of the upper arm muscle area by height and other antropometric measurements. Research was carried out by way of a cross sectional study, including 80% (321 6-13 year olds) of the schoolchildren living in General Lavalle, a rural community of about 3000 inhabitants. The methods and procedures included the evaluation of mother's educational levels and anthropometric measurements. Height (H), weight, mid upper arm circumference, and triceps skinfold (TS) were measured. The body mass index (BMI), the upper arm muscle area (UAMA), the upper arm fat area (UAFA) and the upper arm muscle area by height (UAMAH) were calculated. Variables were grouped by gender and age and transformed into z-scores, using the US anthropometric standards as reference. The results showed that: (1) the mother educational status was, in relation to z-scores, as in an urban population, and (2) the z-scores for BMI, UAFA and TS were above the reference, while the ones for H, UAMA and UAMAH were below the reference. The differences between z-scores in relation to mother's educational levels were statistically significant (p < 0.05). UAMA was correlated strongly with H (r = 0.67). The children of General Lavalle tend to be fatty and overweight, while their muscle mass and H are proportionally low, but with values within the reference. Thus, low muscle mass and H are, in general terms, indicative of low protein reserves, the systematically low-anthropometry found for UAMAH suggests that this index should be used in conjunction with other indexes (e.g. BMI, UAFA) to obtain a more complete assessment of body composition and nutritional status.

Sexual dimorphism in schoolchildren of the Villa IAPI neighborhood (Quilmes, Buenos Aires, Argentina).

Villa IAPI is a poor neighborhood of about 5,000 inhabitants in the overpopulated conurbano bonaerense at the outskirts of the city of Buenos Aires. Most of the adult male residents are construction workers; the rest are temporary workers, underemployed, or unemployed. The inhabitants of Villa IAPI suffer the effects of many adverse socio-economic conditions, including poor nutrition, deficient sanitation, and inadequate medical care. Seven anthropometric variables were measured on 765 children from 6 to 14 years old to test for the presence of an altered pattern of sexual dimorphism. It was found that there were practically no sex differences in standing height and upper-arm muscle circumference. In some age groups, there was a weak but significant sexual dimorphism in body weight and sitting height. The greatest and most persistent dimorphism was found in head circumference, and in triceps and subscapular skinfolds. In all except two age groups, head circumference in males was significantly greater than in females. The other dimorphic variables (body weight, sitting height, and triceps and subscapular skinfolds) showed the opposite relationship. Essentially, females showed increments in subcutaneous fat, while reduced growth in muscle and bone was evident in males. The hypothesis of "better female canalization" can explain the altered dimorphic pattern found in the malnourished Villa IAPI population.

[Effect of gonadal hormones on sexual dimorphism in malnutrition substrates]. / Efecto de las hormonas gonadales sobre el dimorfismo sexual en substrato de desnutrición.

The environmental effect on growth and sexual dimorphism is mediated by endocrinological dysfunctions. It was shown that malnutrition acts on the hypotalamus-pituitary-glandular axis. An experiment was made in Wistar rats to determine the effect of some gonadic hormones on the functional components of the skull to which sex dimorphism was alterated by a postnatal undernutrition. The effects of these hormones in restoring sexual cranial dimorphism was tested. Four treatments were applied: control, with food intake ad-libitum; undernutrition (50% of the control food intake); undernutrition plus periodic injections of testosterone and estradiol to males and females, respectively and sham-operated animals, which were injected with oil vehicle only. A radiological longitudinal study was performed between 20 and 80 days of postnatal age. The length width and height of the neural and facial components were measured on each radiograph. Data were processed by ANOVA and Mann-Whitney statistical tests were performed by means of the SYSTAT 7.0 statistical package. Results showed that gonadic hormones restored the sexual cranial dimorphism by stimulating (testosterone) or suppressing (estradiol) the growth of the cranial components.