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PubMed1989

[A comparative study on the structure and growth of the dentoskeleton and soft-tissue in normal occlusion].

A study of hard tissue and soft tissue contour and growth on normal occlusion among Chinese population was made by means of computerized radiographic cephalometrics. Correlation analysis and polygon methods were applied to analyse the profile contour. The result showed that the dento-skeletal pattern and integumental contour were not necessarily alike, the diversity could be quite prominent. As to the growth change features in soft-tissue and hard-tissue structure, we found that the growth behavior of the lips seemed to show a tendency to follow the dental structure directly. The bony profile tended to become less convex with aging, while the soft-tissue profile remained stable in its degree of convexity.

Adolescent↗

PubMed1995

Calcium carbonate in cholesterol gallstones: polymorphism, distribution, and hypotheses about pathogenesis.

This study of sets of cholesterol gallstones collected consecutively from 222 patients in La Paz, Bolivia, and Mexico City, Mexico, has developed a reliable infrared (IR) spectroscopic method for the detection of calcium carbonate in cholesterol gallstones and provided the basis for simultaneous identification of each of its three polymorphs: calcite, vaterite, and aragonite. The peaks in the 854 to 876 cm-1 region demonstrated 98% sensitivity and specificity for carbonate detection. As little as 3% carbonate by weight could be detected using these peaks. The overall incidence of carbonate was 19% in these populations containing a high proportion of Amerinds. Infrared microspectroscopy of 10 to 50 microns particles, dissected from stones, allowed a ring-by-ring examination of 11 carbonate-containing stones. It was determined that different carbonate polymorphs, when present in the same gallstone, almost always occurred in separate rings. In approximately half of the gallstones, different polymorphs were present in successive layers in the same stone, indicating that conditions governing stone growth changed cyclically. Carbonates were usually precipitated in peripheral layers rather than in the center, supporting the theory that formation of calcium carbonates may be related to episodes of intermittent obstruction of the cystic duct, as opposed to being a major factor in stone nidation.

Calcium Carbonate↗

PubMed1986

Induction of relative growth changes in the musculoskeletal system of the sheep by limb immobilisation.

The function of the limbs of the sheep was modified to study growth changes in the musculoskeletal system. Seven lambs treated with one hindlimb bound to the body, with the hip fully flexed and the stifle and hock fully extended, were reared from the day after birth to about three months old, together with two untreated controls. The effects of this functional alteration were measured by dissecting and weighing components of the whole carcase, by histometry and electron microscopy of the semitendinosus muscles, and by measurements and ashing of the femurs and tibias. With the particular exception of the hip bone and the muscles extending the hip on the bound side, muscles and bones tended to be heavier on the contralateral side in the hindlimb and on the ipsilateral side in the forelimb. The semitendinosus muscle of the bound limb weighed nearly twice as much as that of the controls. The increase in mass was due to a proportionate enlargement of all the muscle components studied. There was, however, a significant increase in the number of myosine adenosine triphosphatase low reacting fibres, as a percentage of the regional fibre population, in the deeper part of the muscle. It was concluded that the enlargement of the semitendinosus muscle was due to stretch and that the histochemical changes were due to chronic nervous stimulation.

Animals↗

PubMedDate not supplied

Deceleration of age at menarche in Poland.

The purpose of this paper is to describe secular growth changes in age at menarche of girls in Poland during the past 40 years. For this purpose data obtained from four consecutive surveys conducted in 1955, 1966, 1978 and 1988 were analysed. Each cohort was selected from settlements: big cities, small towns (approximately 10,000 inhabitants) and villages. Data regarding schoolgirls aged 7-18 years were collected by the status quo method. It was found that after the continuous trend towards an earlier maturation of Polish girls from 1955 to 1978 a substantial slowing down, and even a reverse trend, was observed. The deceleration of the age at menarche is most marked among girls from small towns. The results seem to have been caused by the retardation of menarcheal age in social groups which in the previous examinations were the earliest maturers.

Adolescent↗

PubMed1998

Adipose tissue in human infancy and childhood: an evolutionary perspective.

Humans diverge from most mammals, including nonhuman primates, by depositing significant quantities of body fat in utero and are consequently one of the fattest species on record at birth. While explanations for the fat layer of human neonates have commonly assumed that it serves as insulation to compensate for hairlessness, empirical support for this hypothesis is presently weak. Whether the tissue's abundance at birth and growth changes in adiposity during infancy and childhood might be explained in light of its role as energy buffer has not been assessed, and this possibility is explored through development of a model of fat function and growth centered on two related hypotheses. The first is that the greater adiposity of human neonates is at least partially explainable as an accompaniment of the enlarged human brain, which demands a larger energy reserve to ensure that its obligatory needs are met when the flow of resources from mother or other caretakers is disrupted. The second is that age-related changes in the likelihood of experiencing such disruption have influenced the pattern of investment in the tissue, reflected today in peak adiposity during infancy and a decline to a leaner childhood period. Nutritional disruption is common at birth and until lactation is established, during which time human newborns survive from fats deposited prenatally, suggesting one possible explanation for the early onset of fat deposition. At weaning, the transition from breast milk to supplemental foods and the parallel transition from maternal to endogenous immune protection interact to increase the frequency and impact of nutritional disruption, and this may help explain why newborns devote roughly 70% of growth expenditure to fat deposition during the early postnatal months. Evidence is presented that fat stores are mobilized during infections, hinting at one possible mechanism underlying the association between nutritional status and infectious morbidity and mortality among infants in nutritionally stressed human populations. Consistent with the proposed hypothesis, well-fed infants acquire peak fat reserves by an age of peak prevalence of malnutrition, infectious disease, and fat reserve depletion in less-buffered contexts, and childhood--characterized by minimal investment in the tissue--is a stage of reduced risk of energy stress. The model presented here foregrounds energy storage in adipose tissue as an important life-history strategy and a means to modify mortality risk during the nutritionally turbulent period of infancy.

Adipose Tissue↗

PubMed1987

Heterogeneity of a human T-lymphoblastoid cell line.

A human T-lymphoblastoid cell line (Jurkat) was cloned, and four resulting sublines were characterized in a variety of ways with the objective of gaining information on heterogeneity in cell lines. Within a few weeks of cloning, distinct cellular morphologies and growth patterns became apparent in the four sublines. Growth rate measurements made over 3 months did not show any significant differences between the sublines. Surface protein profiles obtained by radioimmunoprecipitation using antisera in conjunction with extracts from [35S]Met and 125I-labeled cells revealed differences between the sublines. Analysis of total cell DNA showed that one of the sublines possessed only half the chromosome complement of the other sublines and the parental line. Karyotyping confirmed this result and, in addition, demonstrated that chromosome numbers fluctuated around a mean value for each subline. Karyotypic variability became apparent within 2 months of cloning and tended to increase with time in culture. G-banding analysis showed that the analyzed cell populations contained distinctive cytogenetic aberrations. Properties of the cloned sublines were monitored over a 9-month period. One of the sublines that had shown heterogeneous morphology even after 6 weeks maintained the heterogeneity throughout this time. Another subline underwent a marked change in morphology (round to irregular) and growth habit (single cells to large clumps) with increasing time in culture. Interestingly, several alterations to surface proteins accompanied these growth changes. A third subline had relatively stable morphology and chromosome number throughout the 9-month period. The modal chromosome number was hypotetraploid for three sublines and the parent line, but was diploid for another subline. However, it was interesting that progression toward tetraploidy in this subline was apparent after almost 2 years of culturing. The results showed that the original cell line consisted of a heterogeneous assemblage of cell types, some of which were quite unstable. Some implications for research using cultured cell lines are discussed.

Adolescent↗

PubMed1996

[Growth of children with insulin-dependent diabetes. Study of 104 cases].

BACKGROUND: Results of studies of growth in children with diabetes mellitus are still conflicting. In a cross-sectional and longitudinal study, statural growth was analysed in a sample of diabetic children in order to specify its characteristics and relationship with various factors. POPULATION AND METHODS: One hundred and four children (53 girls and 51 boys) with insulin-dependent diabetes for more than 3 years have been studied (age at onset and duration of diabetes, respectively, 6.4 +/- 4.1 and 8.5 +/- 4.8 in girls; 6.1 +/- 3.9 and 7.9 +/- 3.9 in boys; m +/- SD). A control group included 51 boys (age: 8.9 +/- 2.9) and 49 girls (age: 9.3 +/- 2.7). Data were collected every three months. Hemoglobin A1c was measured using high performance liquid chromatography (normal range: 5.0 +/- 1.0%; m +/- 2 DS). RESULTS: At diagnosis, height (evaluated in SD) did not differ between diabetic children and controls. Three years before the onset of diabetes, boys were taller compared to controls (1.02 +/- 0.20 vs 0.41 +/- 0.17; P < 0.05; m +/- SEM). Children five years after the onset of disease were overweight compared to controls (girls: 0.96 +/- 0.16 vs 0.00 +/- 0.20; boys: 0.59 +/- 0.16 vs -0.04 +/- 0.15; P < 0.01; m +/- SEM). Longitudinal study showed a progressive decrease of mean growth velocity starting at least 2 years before the onset of diabetes and proceeding until the end of growth. From diagnosis to the end of height development, there was a growth loss of 0.66 SD in girls (p < 0.01) and 0.69 SD in boys (p < 0.05). This alteration of growth affected more clearly children who became diabetic before the onset of puberty, especially those with early-onset diabetes and bad metabolic control. Growth changes for the first 5 years of diabetes were significantly and negatively correlated with mean hemoglobin A1c levels (r = -0.57). Growth changes from the onset of diabetes to the end of growth were correlated with age at diagnosis, (boys: r = 0.73; girls: r = 0.37). During puberty, girls exhibited a reduced growth spurt, especially when they were overweight and received too low doses of insulin. CONCLUSIONS: On the whole, diabetic children were growing in normal range. Growth was adversely and mainly affected by early-onset diabetes, a long duration of disease, many years of poor metabolic control and, especially in adolescent girls, low doses of insulin and weight excess.

Adolescent↗

PubMed1992

Tumor growth changes the contribution of granulocyte-macrophage colony-stimulating factor during macrophage-mediated suppression of allorecognition.

Tumor-bearing host (TBH) macrophages (M phi) suppress T cell alloresponses, and this study suggests granulocyte-macrophage colony-stimulating factor (GM-CSF), a molecule associated with suppressive M phi activity during tumor growth, signals more immunosuppression. In the absence of M phi, GM-CSF increased T cell proliferation in response to alloantigen. However, TBH M phi-mediated suppression of allorecogntion was further induced by GM-CSF. Allogeneic mixed lymphocyte reaction (MLR) cultures, containing normal host (NH) M phi, were either unaffected or enhanced. Prostaglandin E2 (PGE2), a highly suppressive monokine that decreases alloreactivity, did not seem to be involved in the suppression caused by the TBH M phi/GM-CSF interaction. M phi-CSF (M-CSF) addition to cultures did not reverse the suppression caused by TBH M phi and GM-CSF, and inhibition of PGE2 synthesis did not change the response to M-CSF. TBH Ia- M phi, a suppressor population that predominates among splenic M phi during tumor growth, demonstrated significantly lower reactivity in the presence of GM-CSF. In contrast, alloresponses suppressed by NH Ia- M phi demonstrated higher reactivity in the presence of GM-CSF. The data collectively suggest that TBH M phi respond differently to GM-CSF, and that tumor-induced changes in GM-CSF responsiveness affect M phi accessory ability.

Animals↗

PubMed1980

Morphometry of the renal corpuscle during postnatal growth and compensatory hypertrophy.

Morphometry was used to measure the growth changes in renal corpuscle and glomerular size and composition in outer, middle, and inner cortical layers during postnatal development in normal and mononephrectomized rats. Glomerular growth was 4.16-fold in normal rats and 6.12-fold after nephrectomy. The cell populations in glomeruli showed distinctly different growth patterns. Cellular hypertrophy and hyperplasia during normal growth were 2.72 and 1.52 for epithelial cells, 0.93 and 3.70 for endothelial cells, and 1.28 and 2.65 for mesangial cells; corresponding values during stimulated growth were 2.75 and 1.92, 1.19 and 4.11, and 1.65 and 3.09. A linear transcortical gradient of corpuscle diameters was found in young animals and normal adults, with the mean volume of juxtamedullary renal corpuscles two times greater than that of subcapsular corpuscles in all animal groups. Despite their size variation, a striking transcortical uniformity was evident in the composition of glomeruli in each group with respect to the volume fractions and mean cell volume in each cell population, the volume and surface density of basement membrane, the volume and length density of capillary loops, the volume fraction of mesangial matrix, and the division of basement membrane into peripheral and axial portions.

Animals↗

PubMed1988

Nutrition studies in Thailand: effects of calories, nutrient supplements, and health interventions on growth of preschool Thai village children.

A study of the effects of providing high-calorie and vitamin-mineral supplements to preschool village children retarded in growth and development in Chiang Mai, Thailand was done. The preschool children of 24 villages with a population of approximately 11,000 were divided into five control and intervention groups. The interventions consisted of a village health program, high-calorie snacks, and vitamin-mineral supplements. The supplements when used were provided in day care centers for preschool children. The health and nutrition interventions used did not significantly affect growth during the study period reported from December 1981 to October 1983. Monthly changes in length and weight observed in this and a previous study indicate that growth patterns in Thai children are different from those seen in industrialized societies. Factors other than lack of nutrients and infection may be responsible for the inadequate growth often reported in developing countries.

Body Height↗

PubMed1985

Body weight and the initiation of puberty.

The onset and progression through the various stages of puberty are influenced by a number of factors (Fig. 2). In both animals and humans, the age of puberty appears to be related more to body weight than to chronologic age. Undernutrition and low body fat, or an altered ratio of lean mass to body fat, seem to delay the adolescent spurt and to retard the onset of menarche. According to Frisch, a minimum level of fatness (17% of body weight) is associated with menarche; however, a heavier minimum weight for height, representing an increased amount of body fat (22%), appears necessary for the onset and maintenance of regular menstrual cycles in girls over 16 years of age. This critical amount of body fat implies that a particular body composition, in addition to other environmental and psychosocial factors, is important in triggering and maintaining the pubertal process.

Adipose Tissue↗

PubMed1997

Age related bladder capacity and bladder capacity growth in children with myelomeningocele.

PURPOSE: Currently the relationship between bladder capacity and age in children with myelomeningocele is inadequately understood, such that nomograms derived from neurologically normal children are inappropriately applied to the myelodysplastic population. The aim of the present study was to evaluate age related bladder capacity and bladder capacity growth in children with myelomeningocele, and compare them to those of age matched, neurologically intact children. MATERIALS AND METHODS: Bladder capacity was determined by cystometrography in children with myelodysplasia. Regression analysis was used to derive a relationship between bladder capacity and patient age. Data were stratified by sphincter activity, bladder sensation and uninhibited contractions, and regression analysis was repeated. To evaluate serial growth change in bladder capacity divided by time yielded a yearly bladder capacity growth rate in patients who underwent 2 cystometrograms done at least 3 months apart before age 9 years. RESULTS: A total of 506 children satisfied study inclusion criteria. Bladder capacity (BC) was related to age for the first 9 years by the linear equation, BC = 24.5 (age) + 62. This equation is approximately 25% less steep than published age related bladder capacity in neurologically intact children using the formula, 32 (age) + 73. After data stratification bladder capacity in children with sphincter activity, bladder sensation or no uninhibited contractions approached that of neurologically intact children. In contrast, children without sphincter activity or bladder sensation, or with uninhibited contractions had markedly smaller age related bladder capacity. Bladder capacity growth in the subgroup of 55 children in whom 2 cystometrograms were performed at least 3 months apart before age 9 years confirmed a mean gain in capacity of 24 cc per year. CONCLUSIONS: Normal bladder capacity in children with myelodysplasia is approximately 25% less than in age matched, neurologically intact children. The bladder grows approximately 24 cc per year until age 9 years. When there is failure to store urine, bladder capacity is much smaller, while children with good storage features may attain the bladder capacity expected of age matched, neurologically intact children.

Age Factors↗

PubMed1985

Infant outcome, fetal growth, and pregnancy care: relationships in Indonesian university obstetrics.

The risk of perinatal death is displayed for '56 growth combinations', then contracted into 16 gestational age/birthweight categories (GA/BW) with additional control for antenatal visits (AV;CARE) for 36 000 singleton birth deliveries monitored in Indonesia from 1978-1980. For virtually all GA/BW combinations, the risk of perinatal death (PD) drops impressively with pregnancy care (Care effect on PD). Fetal growth curves are then displayed by infant outcome, the BW difference being the deficit birthweight (DBW) that may serve as a specific life-death growth standard (LDGS)--a reference system in relation to which fetal growth curves, to be controlled for factors other than infant outcome, may be studied. By controlling for maternal education and pregnancy care, the fetal growth curve associated with high pregnancy care and low education (HIAV/LOED) is more favorable than that for low pregnancy care and high education (LOAV/HIED). In Indonesia then, pregnancy care is more important than formal education in the reduction of not only perinatal mortality but also low birthweight (Care effect on fetal growth).

Birth Weight↗

PubMed1991

Long-term follow-up of children with surgically treated vesicorenal reflux: renal growth.

Renal growth after successful surgical correction of vesicoureterorenal reflux (VUR) in childhood was observed in 137 female and 22 male patients over a mean follow-up period of 10.5 years. The renal parenchymal area was determined using a compensatory planimeter. For each measured value, the standard deviation score (SDS) was calculated by comparison with a normal population. On average, renal growth after reflux operation nearly paralleled the expected normal growth rate. Scarred kidneys had a worse growth prognosis than refluxing renal units (RU) without renal damage, growth retardation being correlated with the degree of pyelonephritic changes. The diminished growth rate of scarred kidneys was accompanied by a compensatory growth of the contralateral kidney. In the absence of renal scars, a modest tendency toward growth retardation was seen in kidneys with previously high degrees of VUR. In 39.7% of the unscarred RU with an initial SDS less than -0.5, accelerated growth (change in SDS of 0.5 or more) was observed. Accelerated growth was most accentuated on small unscarred kidneys (initial SDS less than -2.0).

Adolescent↗

PubMed1984

Follicular growth and atresia during the last half of the luteal phase of the guinea pig estrous cycle: relation to serum progesterone and estradiol levels and utero-ovarian blood flow.

The relationships among follicular growth, changes in serum progesterone (P) and estradiol (E) levels, and utero-ovarian blood flow (OBF) through the guinea pig ovary were examined during days 7-16 of the luteal phase (day 0 = estrus) of the estrous cycle and during the subsequent ovulatory (proestrous-estrous) period. Follicles were classified as either viable or atretic based on strict criteria and grouped according to diameter. No changes in follicular growth were observed between days 7-9 of the cycle when serum P levels were elevated and OBF was at low rates. Between days 13-15 when serum P levels were low and both OBF and serum E levels were rising, there was a dramatic increase in the number of viable follicles present in all follicle classes. As the percentage of viable follicles increased, the number of atretic follicles in each size population decreased. Peaks in the number of large follicles (300-450 microns), OBF, and serum E levels were observed during the subsequent ovulatory period. These data suggest that as luteal activity declines during the last half of the estrous cycle, follicular recruitment and growth are stimulated. The concomitant elevations in OBF suggest a supportive role for this parameter in follicular development. In turn, the subsequent elevation in serum E levels serves as an index of follicular maturation. These data suggest that the elevated P levels during the luteal phase of the estrous cycle may either directly or indirectly, through the regulation of gonadotropin secretion, regulate follicular growth in the guinea pig.

Animals↗

PubMed1991

Nutritional support of the medical oncology patient.

Our current ability to favorably influence the adverse consequences of malnutrition in adult patients with established cancer is quite limited. Nutrient provision alone has not been successful in this regard. In fact, the approach of managing cancer patients with weight loss by solely providing calories is almost entirely extrapolated from clinical situations in which the presence of cancer is not a confounding problem and, therefore, may well be seriously flawed. These conclusions may not apply to situations in which special considerations hold, such as childhood malignancies and bone marrow transplantation. Current clinical management strategies for the cancer patient with weight loss require appropriate attention to the potential influence of the selected intervention on more than one parameter. As illustrated in Figure 1, nutritional support, whether by nutrient provision, pharmacologic administration, or a combination approach, differentially influences several parameters including nutritional status, abnormal host metabolism, gastrointestinal symptoms, and/or tumor growth. Changes in these parameters will influence the true end points with clinical relevance, which are patient survival and quality of life. Increased survival of patients with metastatic cancer has been difficult to achieve, even using chemotherapeutic regimens targeted directly at cancer growth. Similarly, nutritional support for patients with advanced cancer has not demonstrated improvement in this refractory parameter. Therefore, at the present time, clinicians must judge whether a nutritional support modality will favorably or unfavorably influence patient quality of life. This end point is of emerging importance in studies of nutritional support in cancer populations. Potential interrelationships among parameters influenced by nutritional support and their effect on clinically relevant end points are conceptually outlined in Figure 1. It is likely that concurrent attention to both optimal provision of nutrients and reversal of abnormal metabolism will be required if successful nutritional support approaches are to be described. Currently emerging clinical results provide some optimism for the future, but they do not unequivocally support the present routine application of any one particular nutrition support strategy for the medical patient with cancer.

Cachexia↗

PubMed1990

[A study of the growth changes of the alveolar arch in Chinese infants].

Sillman, Abe, and Ichilkawa demonstrated that the alveolar arches of infants change with growth and development. They considered that the shape and dimensions of the dental arch will change as the growth of the alveolar arch in infants proceed. They also suggested that recording the growth pattern of the alveolar arch might help us predict the future development of the dental arch. Our material consisted of maxillary and mandibular casts of 164 Kaohsiung infants. It was obtained after pooling the data of studies of Child Dental Growth and Development for research conducted under the direction of Dr. Tien-Yu Shieh of the School of Dentistry, Kaohsiung Medical College. After being examined at the Pediatric Health Center, Chung Ho Memorial Hospital, K.M.C., 106 male infants and 58 female infants from two months to twelve months of age were selected. All individuals were free of abnormalities, chronic disease, or cleft lip and palate. The dimensions of the upper and lower arches were measured with a vernier in combination with other special devices. The growth and developmental curves of the lengths and widths of the alveolar arches were plotted using the means of the alveolar lengths and widths. Results demonstrated that the dimensional coefficients of variance of the anterior alveolar length were greater than those of the other dimensions. The anterior alveolar length varied the most for any given age (in months). The posterior alveolar width and mandibular whole alveolar length showed the least amount of change from two months to twelve months of age. Comparison of the right and left side of the alveolar vector dimension showed no significant difference. It was noted that the alveolar arches of male and female infants grew rapidly. The growth and developmental curves of the alveolar arches of male infants were more steep and rapid than those of female infants. As compared with previous investigations of the Japanese population, the maxillary anterior alveolar lengths and anterior alveolar widths of the present investigation were greater than those of Japanese infants.

Age Factors↗

PubMed1986

Is chloride depletion an important contributing cause of death in infants with bronchopulmonary dysplasia?

A retrospective analysis of infants with bronchopulmonary dysplasia requiring prolonged hospitalization (greater than 100 days) was carried out to determine those factors associated with fatal outcome. Twenty-three infants made up the study population. Eleven infants died and 12 survived (survivors). No differences were noted between the groups regarding ventilator requirement, radiographic changes, and medication use (digoxin, aldactazide), except for furosemide which was used twice as frequently in the group of infants who died v the group of infants who survived (P less than .001). Differences noted between the groups included moderate hypochloremia (chloride less than 80 mEq/L) in all 11 infants who died v six of 12 survivors, severe hypochloremia (chloride less than 70 mEq/L) in the nine of 11 infants who died v two of 12 survivors, metabolic alkalosis (pH greater than 7.45) in nine of 11 infants who died v three of 12 survivors, hypertension (systolic BP greater than 113 mm Hg) in eight of 11 infants who died v one of 12 survivors, decrease in head growth in ten of the 11 infants who died v one of the 12 survivors; these differences were all significant (P less than .001). The metabolic alkalosis and head growth changes appear to be related to the hypochloremia. The data suggest that chloride deficiency may be an important contributing factor in the genesis of poor outcome in infants with bronchopulmonary dysplasia and that close attention to chloride supplementation might influence outcome.

Acid-Base Imbalance↗