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Measurement of serum concentrations of tissue polypeptide-specific Antigen (TPS) has been demonstrated to be useful in diagnosis and monitoring of adult epithelial tumors. So far, no data have been available on normal or pathologic TPS values in children. Therefore, the present study was designed to evaluate the normal values of TPS in childhood. Using a commercial enzyme linked immunosorbent assay (ELISA) kit, serum TPS was determined in 361 healthy children. Median (M) TPS was found to be 107 U/l at birth (n = 124). By the end of the first week, the value rose to M = 150 U/l (n = 68) and then continuously decreased with age (1 week–1 year, n = 45, M = 88 U/l; 1–7 years, n = 75, M = 51 U/l) until reaching the adult level (8–18 years, n = 49, M = 34 U/l). Additionaly, the serum TPS values of 45 mothers right after delivery (M = 161 U/l) were assessed, and there was no correlation to the marker levels determined in the cord blood of their children. The age-dependent distribution of serum TPS in healthy children must be taken into account in the clinical application of this tumor marker. Med. Pediatr. Oncol. 29:218–221, 1997. © 1997 Wiley-Liss, Inc.

The switch from myocyte hyperplasia to hypertrophy occurs during the early postnatal period. The exact temporal sequence when cardiac myocytes cease dividing and become terminally differentiated is not certain, although it is currently believed that the transition takes place gradually over a 1-2-week period. The present investigation has characterized the growth pattern of cardiac myocytes during the early postnatal period. Cardiac myocytes were enzymatically isolated from the hearts of 1, 2, 3, 4, 6, 8, 10, and 12-day-old rats for the measurements of binucleation, cell volume and myocyte number. Almost all myocytes were mononucleated and cell volume remained relatively constant during the first 3 days of age. Increases in cell volume and binucleation of myocytes were first detected at day 4. Myocyte volume increased 2.5-fold from day 3 to day 12 (1416 +/- 320 compared to 3533 +/- 339 microns 3). The percentage of binucleated myocytes began to increase at day 4 and proceeded at a high rate, reaching the adult level of approximately 90% at day 12. Myocyte number increased 68% during the first 3 days (from 13.6 +/- 3.5 x 10(6) at day 1 to 22.9 +/- 5.6 x 10(10) at day 3) and remained constant thereafter. To confirm that no further myocyte division exists after 4 days, bromodeoxyuridine (Brdu) was administered to 4-day-old rats and the fate of DNA-synthesizing myocytes was examined 2 h and 2, 4, 6 and 8 days after Brdu injection. About 12% of myocytes were labeled with Brdu at 2 h and all were mononucleated at that time. Gradually, these Brdu-labeled myocytes became binucleated. However, the percentage of labeled myocytes in all groups was identical, indicating that DNA-synthesizing myocytes were becoming binucleated without further cell division after 4 days of age. Within 8 days after injection, approximately 82% of total labeled myocytes were binucleated, while the others remained mononucleated. Sarcomeric alpha-actinin was fully disassembled in dividing myocytes of 2-day-old rats, while typical alpha-actinin striations were present in dividing myocytes of 4-day-old rats. The results from this study suggest that a rapid switch from myocyte hyperplasia to hypertrophy occurs between postnatal day 3 and 4 in rat hearts.

Modifications at V-(D)-J junctions increase the diversity of T-cell receptors (TCR). It has been shown that the levels of N-nucleotide insertion at the V-(D)-J junction in TCR transcripts are different between fetal and adult stages. To clarify developmental stages and pathways of gamma delta T cells in the liver, we analysed the nucleotide sequence of V gamma 1.1-J gamma 4 junctions of intra-hepatic lymphocytes (IHL), spleen cells and developing thymocytes from normal and athymic nude mice. The level of N-insertion increased in thymocytes during ontogeny. The percentage of V gamma 1.1-J gamma 4 transcripts with N-insertion was 3% at day 16 of gestation, 42% at newborn, and 89% at 7 weeks. Transcripts from normal IHL showed intermediate levels of N-insertion between those of newborn and adult thymocytes. In contrast the percentage of N-insertion in nude IHL was 47%, and this value was comparable to that of newborn thymocytes. Among the transcripts of normal IHL, the sequences common with nude IHL showed a newborn level of N-insertion (38%), and the remaining sequences showed an adult level (89%). These results suggested the possibility that V gamma 1.1-expressing T cells in IHL might be a heterogeneous population consisting of the cells developed extrathymically as well as the cells developed intrathymically. The V gamma 1.1-J gamma 4 junctions from spleen cells showed less variability than those from IHL and adult thymocytes. It suggested that gamma delta T cells bearing specific V gamma 1.1 TCR develop and/or home in the spleen.

Drugs can be metabolised by many different pathways (see chapter 1) and many factors can determine which pathway is used by which drug and to what extent a particular drug is biotransformed by a particular pathway. These factors range from the species of organism studied to the environment in which that organism lives. In order to discuss this topic, the factors affecting drug metabolism will be split into internal (i.e. physiological and pathological) factors (discussed in this chapter) and external factors (i.e. diet and environment) (discussed in chapter 5). These are, of course, purely arbitrary divisions and much interaction exists between the various factors (cf. hormonal, sex and age influences) — such interactions will be pointed out where they are important. The factors discussed here are also not an exhaustive list and other factors that play a role in controlling drug biotransformation will be found in the Further Reading section at the end of chapter 5. The factors to be discussed here are: internal species genetic (strain) age sex hormones disease external diet environment Each of these factors will be examined in turn giving examples of the differences seen. Internal factors are discussed in this chapter, while external factors are discussed in chapter 5.

The postnatal development of Peyer's patches was investigated using routine histological and immunohistochemical techniques, focusing especially on the formation and increase in number of lymphoid follicles. In addition, we studied the influence on the development of lymphoid follicles in Peyer's patches of a sublethal dose of whole-body X-irradiation at an earlier postnatal age. At 1 day after birth, surface-IgM (sIgM)-bearing cells (B lymphocytes) were scattered throughout the Peyer's patch. At Day 3, sIgM-bearing cells had accumulated to form primary follicles in association with domed elevations. OX2-positive reticular cells (FDC) were detected in the centers of primary follicles at Day 5. The first appearance of germinal centers within lymphoid follicles was noted at 18 days, and at 21 days almost every follicle contained a germinal center. At Day 5, each Peyer's patch contained 6-8 lymphoid follicles, with the lymphoid follicles subsequently increasing in size and number. The mean number of follicles per Peyer's patch became 11.1, the adult level, at 21 days, and remained at this level for the next 15 weeks, even though respective follicles continued to enlarge during the observation period.Three-week-old rats received 400rad whole-body X-irradiation. At 3 and 7 days after treatment, lymphocytes were largely depleted from Peyer's patches, leaving behind the structural framework of the lymphoid follicles, interfollicular zones and domes. Stromal cells in the follicle remnants retained a positive reaction to OX2. By 14 days after X-irradiation, lymphoid follicles together with their germinal centers had begun to repopulate, and the number of restored lymphoid follicles per Peyer's patch was comparable to that in non-irradiated 3-week-old rats.In conclusion, the present results show that the majority of lymphoid follicles and their stromata are well established in Peyer's patches during the first 3 weeks after birth and are maintained for weeks and even months.

To investigate the development of Arg-vasopressin (AVP) content and its diurnal rhythm in the suprachiasmatic nucleus (SCN), AVP was measured by enzyme immunoassay in the rat pup SCN punched out from tissue slices obtained at postnatal day (PD) 1, 5, 10, 12 and 20 from animals maintained under a light-dark cycle (LD). The AVP levels, measured at a restricted time of day, increased from PD1 reaching the adult level at PD10–12. Diurnal rhythm similar to that in adults was evident at PD10–12 under the LD conditions used. The peak value of AVP was observed at the earlier light period, and its trough occurred at the end of the light period. The circadian rhythm remained for 7 days under constant dark (DD) or constant light (LL) conditions. These results indicate that the AVP, one of the output signals from the SCN, starts to oscillate after PD10–12, and shows a free-running rhythm during the nursing period.

Purpose: Serum alkaline phosphatase (sALP) levels show great variation with age and sex in children and adolescents. We aimed to study pediatric ageand sex-specific reference ranges for sALP and how the pattern changed according to age . Methods: Cross-sectional results from 1366 healthy Korean children and adolescents (10-19.9 years) from the Korean National Health and Nutrition Examination Survey were analyzed. We constructed ageand sex-specific reference data for sALP with a Hitachi Automatic Analyzer 7600 using Pureauto S ALP. We assessed its peak both in relation to age. Results: Reference values for sALP according to age were constructed. Peak sALP levels were found at 12-13 years in boys (P < 0.001). Total sALP levels decreased to the adult level at the age of 17 in boys and 15 in girls, respectively. Conclusion: This study provides reference values for sALP by age for Korean children and adolescents. This normative data that includes upper and lower limits will provide a basis from which to better evaluate sALP levels, especially for bone disorders such as rickets and vitamin D deficiency. However, caution should be made in interpreting sALP levels because different buffers might lead to different values in the same serum.

The activity of porphobilinogen deaminase (PBGD), an enzyme whose partial deficiency is associated with acute intermittent porphyria (AIP), changes during development. Little is known about the postnatal change of PBGD activity and the prevalence of its electrophoretic variant in the Japanese population. The activity of PBGD was measured fluorometrically in 194 infants aged 0–12 months, while isoelectric focusing of PBGD was performed in 400 healthy Japanese adults aged 20–45 years and 30 children with various hematological disorders aged 1–15 years. The PBGD level was 1.9 times higher in the neonates than in the adults, decreased abruptly during the first month of life, and reached the adult level at the age of 9 months. None of the 400 healthy Japanese adults and the 30 children with hematological disorders showed any electrophoretic variant. These results suggest that there is no need to consider any polymorphism in the gene dose study of PBGD and that the biochemical screening of AIP is applicable to since the late infancy.

Background and Objectives：Detailed information on how ossicles change in the developing temporal bone would be helpful in understanding biomechanical knowledge of ossicles. In this study, three dimensional structural images of mouse were investigated through Micro-CT to understand developmental anatomy of its ossicles. Materials and Method：Thirty five temporal bones of BALB/c mice, aged from gestational day 11 to postnatal day 21, and adults were investigated. Three-dimensional highresolution reconstructions of the ossicles of the left sided temporal bones were obtained using a Micro-CT system. The right sided temporal bones were used for the histological study. Results：Internal biomechanical characters (volume fraction, structure model index, degree of anisotropy, etc) of murine ossicles and temporal bones were attained to the adult level at postnatal day 21. Conclusion：This study will be useful in understanding the more accurate microstructure of murine temporal bone, and will provide the anatomical basis for the future animal studies. (Korean J Otorhinolaryngol-Head Neck Surg 2009;52:327-34)

This study was performed to identify the chronological changes of the knee angle or the tibiofemoral angles in normal healthy Korean children. Full-length anteroposterior view standing radiographs of 818 limbs of 452 Korean children were analyzed. The overall patterns of the chronological changes in the knee angle were similar to those described previously in western or Asian children, but the knee angle development was delayed, i.e., genu varum before 1 yr, neutral at 1.5 yr, increasing genu valgum with maximum a value of 7.8 degrees at 4 yr, followed by a gradual decrease to approximately 5-6 degrees of genu valgum of the adult level at 7 to 8 yr of age. These normative data on chronological changes of knee angles should be taken into consideration when evaluating lower limb alignment in children.

In this study a series of Sicilian neonates was studied in order to investigate about the distribution of serum lipid and apolipoprotein at birth and the differences with adults. A series of 200 term, healthy newborns was studied. Total cholesterol (TC), triglyceride (TG), HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C), apo AI and apo B were assayed in all cord blood samples. TC mean value was 63.2 mg/dl and HDL-C represented about the 40% of TC: no differences was found between male and female newborns. In neonates TC and LDL-C were about, three-fold lower than adults, while HDL-C was about the 60%; apo AI and apo B were respectively about 60% and 30% of adult levels. 3.5% of newborns presented TC levels above the mean + 2 standard deviations. In conclusion lipid and apolipoprotein distributions in Sicilian newborns are not different from that of other population and there are no differences between males and females. It should be interesting the follow up of “hypercholesterolemic” newborns in order to establish if it is possible to do a neonatal screening of familial hypercholesterolemia.

All terrestrial mammals studied so far do maximal amounts of sleeping at birth, with sleep time gradually decreasing to adult levels. This has led to the concept that sleep, with its characteristic immobility and unresponsiveness, is necessary for brain and body development. We reported1 that dolphins and killer whales have a very unusual developmental pattern: neonates are maximally and continuously active at birth, and this activity diminishes over a period of months to the adult level; in the postpartum period, mothers also abruptly cease the characteristic ‘hanging’ that constitutes the typical sleep behaviour in bottlenose dolphins and killer whales2,3,4,5. We did not claim that all sleep was abolished in the postpartum period. Rather, we reported that immobility was absent and that typical sleep posture increases with age, a pattern opposite to that seen in all land mammals studied so far. Sekiguchi . 6 and Gnone . 7 challenge our conclusions.

The Possible Relation Between the IgE Concentration-, and the Prevalence of Bronchial Asthma in Childhood L Endre*, L S6ti§, Gy Mezei~, T Dolinai~, G Lakos,,, A Kulcsdr~, S Sipka~, LM Dubuske@ *Central Hospital of M.A,V, Budapest, Hungary §Outpatient Clinic of MAV, Szombathely, Hungary YFirst Pediatric Clinic of Medical University, Budapest, Hungary ~J6sa Andrfis Hospital, Nyiregnhfiza, Hungary ~dIIrd Internal Medical Clinic of Medical University, Debrecen, Hungary @Immunology Research Institute of New England, Fitchburg, MA The serum immunoglobulin E levels were determined in 305 non-allergic Hungarian children by laser-nephelometry using Behring reagents. During the calculation of the normal levels, children were excluded from the investigation who had IgE levels above 200 kU/L when below 2 years of age, or above 250 kU/L when between 3 and 6, or above 300 k/UL when older than age 7. On this basis 13 children were excluded from the 305. The results are listed on Table I. The Hungarian children have higher IgE levels especially under the age of 6 years than previously reported for Swedish or German children. However, the Hungarian children achieve the adult level of IgE by the age of 3, perhaps because of some helminthiases. The prevalence of childhood asthma in Hungary is much lower (for example in Budapest it is 2.26%) than in the most industrialized countries, suggesting a paradoxical relationship in Hungarian children between production of IgE and clinical signs of atopic asthma.

The food security status of participants in the Iowa Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) was studied through a written survey in April, 1997 prior to implementation of Welfare Reform measures in the state. The survey used the Radimer/Cornell hunger and food insecurity measures to identify food security status. Demographic information and participation in other food assistance and nutrition education programs was also collected. Ten percent of the active participants were randomly selected to complete the survey (n=6,700). Three thousand four hundred seventy-two participants (3,472 or 52%) completed the written survey. According to the food insecurity measures, 46.4% of respondents were food secure and 53.6% experienced some level of food insecurity. 50.5% of all respondents experienced food insecurity at the household level, 22.0% reported food insecurity at the adult level, and 5.6% reported child hunger in their family. Seventeen percent of respondents reported receiving both Food Stamps and Family Investment Program benefits (previously known as the Aid for Families with Dependent Children) and 12% received only Food Stamps. A follow-up survey is planned in 1999 to study the impact of Welfare Reform on food security status of families participating in the WIC Program. Although WIC participation is not affected by the Welfare Reform measures, food insecurity may increase as families lose benefits from other programs due to failure to meet work requirements.

1. 1. The respiratory properties and 2,3-DPG concentration were studied in blood of rats from birth to 83 days of age and compared with adult values. 2. 2. Newborn rat blood had a Hb concentration of 9.3 ± 1.1 g% significantly lower (P < 0.01) than 14.2 ± 1.4 g% for adults. 3. 3. The lowest value for Hb concentration occurred at day 5, then it rose to reach adult levels by 83 days of age. 4. 4. The Bohr factor for rat blood was −0.603 ± 0.066 Δ log pO2/ΔpH (N = 18). 5. 5. The P50 of newborn rats was significantly lower (P < 0.01) than adult values (24.6 ± 1.0 vs 38.7 ± 1.8mm Hg), but rose to the adult level by day 23 of life. 6. 6. The concentration of 2,3-DPG in newborn rat blood was 2.53 ± 1.78 μmol/g Hb, significantly lower (P < 0.01) than 13.93 ± 1.66 μmol/g Hb for adults. 7. 7. The concentration of 2,3-DPG rose steadily in the postnatal period and reached adult levels by day 18, close to the time when P50 values also reached the adult range. 8. 8. The pH difference across the red cell membrane decreased with age and therefore does not explain the rise in P50. Neither P50 nor 2,3-DPG concentration values in the neonate overshot adult values. 9. 9. The data collected in this study and information available for other species suggest that the time of disappearance of postnatal anemia depends upon the growth rate of the species.

1. 1. One-day-old Rousettus aeyyptiacus reveal thermoregulatory heat production at least for the first minutes when ambient temperature drops. This metabolic response to cold reaches the adult level in the third week of age. 2. 2. Thermoregulation can be proven from the 7th day of life by means of control variations in body temperature. 3. 3. The postnatal shift in the set point adjustment of body temperature is shown. 4. 4. The calorigenic effect of exogenous noradrenaline is significant after the first week of age reaching its maximum in the third week.

Changes in the ratio of two molecular species of ethanolamine plasmalogen, PI-LE-1 and PI-PE-2, of human central nervous system myelin during development were measured by a TLC procedure. The ratio was found to decrease sharply with age up to 6 months as a result of an increase in the amount of PI-PE-2, believed to be a unique myelin lipid with 18:1 chains in both positions of the glycerol. The ratio continued to decrease gradually with age and did not reach the adult level until an age of 17 years.

The mechanism leading to the difference in hepatic triacylglycerol metabolism between female and male rats was investigated by studying the ontogeny of hepatic soluble phosphatidate phosphohydrolase activity in feeding animals of both sexes. A sevenfold increase occurred within 12 hr of birth, returning to the adult level during the third postnatal day. The changes in enzyme activity were followed by similar changes in hepatic triacylglycerol concentrations. A sex difference was observed only in the adult rats, where the enzyme activity in the livers of feeding female rats was about 25% higher than that in feeding males. The effects of gonadectomy and sex steroids were studied in a separate series of experiments on fasting animals. The activity of the soluble enzyme was 65% higher in the intact female rats than in the males, and that of the microsomal enzyme 130% higher. The activity ratio between the soluble and microsomal enzyme in the male rats was 4.3 on a liver wet weight basis with the methods used. Gonadectomy increased the soluble and microsomal activities by 25% and 80% respectively within 6 wk in the male rats. The soluble and microsomal activities were still at the control levels 2 wk after the gonadectomy, and subcutaneous implants of testosterone or estradiol resulting in 10-fold increases in plasma hormone levels had no effects on these enzyme activities, although testosterone caused 50% decrease in the hepatic triacylglycerol concentration. These data indicate that, if hormonally mediated, the postnatal increase in phosphatidate phosphohydrolase activities is not related to sex steroids and also suggest that the basis of the sex difference in hepatic soluble phosphatidate phosphohydrolase activity remains to be established.

This study showed a rapid and direct method for determining selenium concentration in plasma by flameless atomic absorption spectrophotometry, and differences in plasma selenium concentration in healthy children and adults. A direct method is possible, since selenium is heat stable in the presence of nickel. With this method, the recovery of selenium added to plasma was 100.3 +/- 5.7%, and the relative standard deviation in repeated determinations of pooled plasma selenium was 3.0% and 6.8%. The plasma selenium concentration in adults was 99.4 +/- 12.5 ng/ml, lower than reported concentrations from the United States and Canada, and higher than those from New Zealand. These variations may reflect dietary habits, bioavailability of selenium compounds in diet, racial difference, or different analytical methods. The mean concentration of plasma selenium at 1 to 6 months of age (51.0 +/- 13.1 ng/ml) was significantly lower than in adults (p less than 0.001); it increased gradually and steadily to the adult level with age. This age-related difference of plasma selenium level is similar to that reported previously.

Creatine kinase (CK) activity and isozyme patterns were assessed in newborn and adult rat anterior tibial muscle in response to denervation. Total CK activity was low in the control neonatal muscle, gradually increasing to the adult level within 1 month. Denervation prevented this normal increase, and, therefore, CK activity was reduced to 25% of control at 2 months. In the denervated adult muscle, total CK activity decreased to 50% of control within 3 weeks and remained at that level. Denervation of neonatal muscle resulted in a greater conservation of MB isozyme compared with controls. The alteration in BB isozyme expression was even more dramatic with a 33-fold difference expressed at 2 months in terms of percent total CK in denervated vs. control muscle. In denervated adult muscle, MB and BB isozyme activities increased gradually, attaining levels 3-fold and 13-fold, respectively, above control muscle at the end of the experimental period.

The purpose of the present work was to investigate the influence of age, sex and genetic factors on the quantitative antibody response of sheep, when environmental conditions were kept under strict control. Data provided by this experiment show that sheep of 3 months old are capable of developing a measureable response to a single intravenous injection of chicken red blood cells, but the average level of haemagglutinins produced by young lambs is significantly lower than that found in adults (2 to 5 years old) of the same sex (p less than 0.001). At 7 to 8 months of age, the antibody response observed in lambs reached the adult level. There is also a tendency for a better response in females than in males, but the observed difference is small (0.6 log2) and statistically not significant. Heritability estimates clearly indicate a genetic influence on the quantitative antibody response of sheep to chicken red blood cells.

English Handbells can add a meaningful adult level musical activity to the program of a nursing home. This article contains practical ideas and helps for starting a bell program in your facility.

The development of the mixed function oxidase system has been studied in pouched and young-at-heel joey quokkas. Cytochrome P-450 was first detectable at 35 days, rose sharply to one-third of the adult level by 53 days, and reached levels in the adult range between 155 and 255 days. NADPH-Cytochrome c reductase was approximately one-fifth the adult level at 45 days and , by 80–105 days of life, had reached values within the range for adult animals. Benzpyrene hydroxylase activity was barely detectable at 35 days; its development lagged behind that of the components of the cytochrome P-450 system and adult levels were not seen until 200 days. Electron microscopy showed that hepatocytes in 20- and 35-day joeys contained some short chains of rough endoplasmic reticulum. Areas of smooth endoplasmic reticulum were first evident at 45 days and at subsequent stages (80, 100, and 150 days and adult) increasing concentrations of both smooth and rough endoplasmic reticulum were present. Development of the mixed function oxidase system in the quokka liver is slow and resembles more closely the pattern of development in human fetal liver than that in many common laboratory animals.

The effect of nicotinic acid on the changes of rat brain cerebroside levels has been studied during brain development. There is a gradual increase in the concentration of cerebroside from 12 days of age to adult level at approximately 47 days of age. However, the concentration of cerebroside was significantly lower in brain of rat fed the nicotinic acid-deficient diet. Therefore, nicotinic acid may play an important role in cerebroside synthesis in brain of developing rat.

Preoedipal patients present a special problem in group treatment. This is because their difficulties arose largely before they learned to use words. Such patients are prone to act rather than talk. They do not respond well to interpretation. They must be approached and influenced through feelings. We can utilize the group to provide them with maturational experiences, helping them reach a more adult level of mental functioning so that our usual technical interventions can be brought into play. The paper discusses methods for enhancing this process, including reflection, emotional communication, using reconstruction to close developmental gaps, and immunization.

1. The number of muscle fibres innervated by individual motor neurones (motor unit size) was measured in lumbrical muscles of rats aged 0--28 days, during the period of elimination of polyneuronal innervation. Motor unit sizes were determined from twitch tension measurements combined with muscle fibre counts made from histological sections of the muscles. 2. The relative tensions contributed by individual motor units declined from about 25% of the total tension at birth, to about 9% at 28 days of age. Intracellular recordings showed that part of this decrease reflected the elimination of synapses from polyneuronally innervated muscle fibres. 3. During the same period, however, new muscle fibres were produced. The total number of muscle fibres present increased from about 500 at birth to about 950 fibres in mature muscles. 4. These two processes were offsetting: some synapses were eliminated (from polyneuronally innervated fibres) while simultaneously others were formed de novo (on newly produced muscle fibres). Quantitative measurements showed that for the first 10 days after birth, there was little change in motor unit size. Thereafter production of new muscle fibres ceased, and motor unit size decreased to the adult level. 5. It is concluded that during early post-natal development, a lumbrical motor neurone maintains a nearly constant number of synapses, but extensively reorganizes its synaptic field, retracting synapses from some muscle fibres, while forming new synapses with other fibres.

The developmental curve for face recognition displays a temporary dip in performance during early adolescence. Two experiments were conducted to investigate whether this regression is a general characteristic of visual memory development or is peculiar to face recognition. In Experiment 1 children (8-15 years) were asked to recognize pictures of flags. No age differences were found although there was some indication of a slight dip at 13 years. The second experiment tested recognition of houses (7-15 years) and found a significant improvement in accuracy between 7 and 12 years and a significant decline between 12 and 13 years, followed by a recovery to adult level. Possible explanations for these regressions in memory development were discussed.

The iron status and transfer of iron through the milk during lactation were determined in a marsupial, the quokka, Setonix brachyurus. Lactating animals were not anaemic and had similar liver and spleen non-haem iron values to non-lactating female adult animals but about 40% less non-haem iron than male adults. The milk iron concentration was very high during the period of lactation when the young is confined to the pouch, averaging about 20 micrograms/ml (eight times the plasma iron concentration), but fell markedly at the time when the young commence to leave the pouch. Blood haemoglobin concentration increased during pouch life of the young to reach adult levels at about 180 days, and liver non-haem iron concentration increased during the same period to values nearly 20 times greater than in their mothers. After the young left the pouch the non-haem iron concentration fell rapidly to the adult level while haemoglobin concentrations were maintained. It is concluded that milk is an adequate source of iron during pouch life of the quokka and enables the animal to build up iron stores which can be utilized after leaving the pouch.

The proteolytic activity of gastric mucosa markedly increased from 2 to 4 wk of age in rats and from birth to 8 wk in pigs. In calves it was at adult level at birth, then decreased until d 14 and remained at a relatively low level up to d 56 of age. Early postnatal glucocorticoid injections increased (P less than .05) the proteolytic activity of gastric mucosa in rats, decreased (P less than .05) the abomasal proteolytic activity in calves and had no significant effect in pigs. The high levels of proteolytic activity observed in the rat at earlier ages after glucocorticoid treatment suggested a precocious maturation of the gastric mucosa. Injections of different doses of hydrocortisone acetate and dexamethasone to calves and rats indicated that proteolytic activity of gastric mucosa is only sensitive to high doses (i.e., nonphysiological) of glucocorticoids. The response of gastric mucosa to glucocorticoid injections depended on the animal's age; maximum response was obtained in the early postnatal period while minimal response was observed after weaning.

Uridine phosphorylase activity was assayed in heart extracts from rats of different postnatal age. Activity was low at birth, increased to a maximum at 8–14 days of postnatal development and then decreased to a low adult level. The switch from cellular hyperplasia to hypertrophy determined by the ratio proteins/DNA occurred at day 18 of development. It is suggested that the activation of uridine phosphorylase activity during the early life of the rat may be a critical element of the onset of hypertrophy.

This study is the examination of the impact of childhood participation levels in outdoor recreation on the activity level of that individual as an adult. The study is based on a stratified random sample of adult residents in eight northeastern Iowa counties. Forty‐five outdoor recreation activities were used to determine the “carry‐over” of participation from childhood to adulthood. The results indicate a direct effect of the childhood level of participation on adult level of participation. Only eight of forty‐five activities seem to carry over; therefore, prediction of specific activity carryover is very limited. Implications for educating for leisure and aspects of socialization are discussed.

Adult illiteracy is a serious national problem that affects a minimum of 23 million Americans. Unfortunately, adult educators who face the important challenge of obviating this problem seem divided as to which methods for teaching reading to adult learners are most effective. This article provides a brief review of the literature regarding the current practices for teaching reading to adults and children. The author suggests that much of the methodology that has proven effective with school-aged poor readers, such as the teaching of phonics in a direct instruction manner, may be quite appropriate for use at the adult level.

Hunting participation, as indicated in the 1983 Nationwide Recreation Survey, is examined to determine the relationship between age of first hunting experience and adult level of participation. A statistically significant association between these two variables is found. In addition, more than 83 percent of those who hunt began their involvement by 18 years of age. The findings have implications for future hunting participation and the provision of programs for hunters.

The estrous cycle of Baiomys taylori averages 4.9 days. The gesta-tion period is estimated to be 22 to 23 days. A postpartum estrus is frequent. Puberty occurs as early as 28 days of age. Seven of 10 females between 25 and 29 days of age conceived within a week after pairing. The average weight of 47 individuals at birth was 1.20 ± 0.08 (SD) grams. The adult level of body temperature could be maintained at ages between 10 and 15 or 15 and 20 days for neonates exposed to 30 and 28°C, respectively, for a period of 2 hours. Growth during the first 20 to 35 days occurred in two phases with the first phase exhibiting an instantaneous growth rate of 7.50 ± 0.32 and 7.29 ± 0.42 per cent of body weight per day for experimentals (those young used for metabolic as well as body temperature and body weight measurements) and controls (those young used only for body weight measurements), respectively. The second growth phase commenced at 11.3 days for the experimentals and 17.0 days for the controls. The second growth phase averaged only. 4.01 ± 0.26 and 3.30 °: 0.52 per cent of body weight per day for the experimentals and controls, respectively, and coincided with the full development of homeothermy. At a body temperature of 36 to 37°C and a body weight of 2.0 to 2.5 grams—the lower size limit for homeothermy—the oxygen consumption was 3.6 ° 0.40 (2 SE) cc O2/g/hr if the ambient temperature was 30°C. The oxygen consumption for neonates averaging 22.5 ± 0.7 days of age was 4.31 ± 0.16 cc O2/g/hr at an ambient temperature of 30°C. This relatively high level of oxygen consumption indicated that 30°C was below thermal neutrality, the ambient temperatures at which the oxygen consumption of adults is 1.95 ± 0.25 (2 SE).

Summary The ontogenic development of GABA receptors was studied in a Na + -free medium to frozen, thawed and Triton X-100 treated membranes obtained from different brain areas of rat at various ages. At birth, 3 H-GABA binding sites are present in all the brain regions we have examined in a relatively high amount, about 40% of the adult level, and reach the adult levels approximately three weeks after birth. The change of 3 H-GABA binding with age is due to an increase of the number of the binding sites and not to a modification of the affinity of the receptors for 3 H-GABA.

The maturation of various enzymes and intermediates of the 5-hydroxytryptamine (5-HT) biochemical pathway have been measured in the spinal cord of the mouse between 1 day postpartum and adulthood. During the early postnatal period, most components are adult-like or near adult-like, increase to levels greater than the adult by the second week, and return to adult levels thereafter. 5-HT, however, never exceeds adult level and does not attain it until week 4. The early maturation of 5-HT metabolism in the cord is in keeping with the caudal/rostral gradient of maturation in the brain. Possible reasons for this are discussed.

We have determined the plasma concentrations of protein S and C4BP in 25 term and 26 preterm infants by radioimmunoassay. Both the total concentration and the concentration of free protein S were quantified. The concentration of C4BP was very low in preterm infants (mean 6% of the adult level). In term infants, the level had increased to a mean of 18%. Total protein S was decreased both in preterm and term infants, 4.0 mg/l and 6.8 mg/l respectively, as compared to the mean adult concentration, 20.6 mg/l. In preterm infant plasma, free protein S was the predominant (85%) form, probably due to the very low C4BP level. In plasma from term infants, free protein S represented 68% of the total protein S, the corresponding value in adult controls being 37%. The plasma concentration of free protein S in preterm and term infants was 3.3 mg/l and 4.6 mg/l, respectively (mean adult value 7.6 mg/l). These results demonstrate that, while the total protein S concentration in preterm and term infants was very low in comparison to the adult level, the difference in the concentration of the anticoagulant, active, free form of protein S between infants and adults was less pronounced.

In vitro brain neuronal protein synthesis was studied in control and postnatally malnourished newborn rats. The malnourished progeny had, respectively, 20.6% and 72% of the body and brain weights of the controls at 66 days of age. A neuron-enriched fraction (NEF) was separated from rat forebrain. Evaluation of the free leucine pool of the NEF showed decrease with age but no alteration with malnutrition. Protein synthesis was estimated by the rate of in vitro incorporation of 14C-leucine into the TCA-insoluble protein of the NEF in rats at the ages: 1, 7, 14, 21, 28, 35 and 66 days. Protein synthesis in the NEF declined with age in both nutritional states except for a rise to day 14 in the control group. Rates of synthesis declined sharply after 21 days of age reaching an adult level of protein synthesis after about the first month of life in both nutritional states. 14C-leucine incorporation was significantly higher in control over malnourished animals on days 14, 21 and 28.

The levels of immunoglobulin Ig G, Ig M and Ig A in the plasma of Japanese monkeys (Macaca fuscata) from birth to 180 days of age were examined. The level of Ig G reached a minimum at 50 to 80 days of age, when the neonates weighed 600–800 g. Anti streptolysin O antibody decreased from birth with age and was not detected from day 80 to 150. The level of Ig M showed a temporary peak at 20–30 days of age and increased again from 60–80 days. The concentration of Ig A increased gradually to reach 20% of the adult level at day 180.

Lung infections are a common cause of morbidity and mortality in neonates. To evaluate neonatal lung defenses against pneumococci, we challenged rats with aerosols of encapsulated pneumococci in an airborne infection apparatus. Whereas adult rats cleared greater than 95% of inhaled type 1 or type 25 pneumococci within 4 h, pneumococci proliferated in the lungs of newborn rats and reached 200-600% of the baseline value by 4 h and 1000-1700% by 24 h. As neonatal rats matured, their ability to clear inhaled pneumococci improved, but compared with adults some impairment in clearance was present until approximately 4 wk of age. Newborn rats had significantly fewer resident alveolar macrophages per g of lung tissue than did adults (p less than 0.001). Although the number of resident macrophages increased with time, a significant deficit in alveolar macrophages persisted for the first 3 wk of life (p less than 0.01). Aerosols of pneumococci caused an influx of granulocytes into the lungs of adult rats within 4 h, compared with 24 h for neonatal rats. Even at 24 h after pneumococcal challenge, newborn rats had significantly fewer granulocytes per g of lung tissue (p less than 0.05) than did adults, although 7-day-old rats had reached an adult level by this time. Significant (p less than 0.05) increases in granulocyte chemotactic activity were observed in lavage fluids of adult, but not newborn, rats after pneumococcal challenge. Thus, impaired clearance of pneumococcal aerosols by neonatal rats was associated with an age-dependent deficiency in numbers of resident alveolar macrophages and impaired generation of chemotactic activity and recruitment of granulocytes to the lung.

Causes for anxiety in visiting the dentist, plus guidelines on how the dentist can control these anxieties are discussed. Pain is not the sole reason for fear of the dentist. Anxiety, or fear of the unknown, is a major factor, partly because the oral cavity is such an emotionally charged area of the body. From the time of birth, through the adult level, the appearance and functions of the mouth play an important role in the psychic life of an individual. This article traces some of the causes and manifestations of anxiety, and offers guidelines on how the dentist can deal with it.

Twenty boys at each age level 7, 10, and 13 years and 20 adult males were tested for choice manual reaction times to photographs of faces or letter pairs tachistoscopically presented 3 1/2 degree to the left or 3 1/2 degree to the right of a central fixation point, in the left visual field (LVF) or the right visual field (RVF) respectively. All subjects were right-handed. Subjects were tested monocularly. They used a different hand and a different eye in the first and second half of trials. Eye order and hand order were randomized across subjects. Seven- and 10-year-olds were intermittently rewarded with a poker chip following fast correct responses. Analysis of correct reaction time scores indicated an overall LVF superiority for the speed of response to faces, but no significant field differences for responses to letter pairs. The interaction of these field-stimulus effects with age was not significant, suggesting that the obtained field effects with faces and letter pairs were consistent across the range of ages tested. The results of comparisons of field differences within individual subjects suggested a "switchover" from a left-field advantage with letter pairs at age 7 to a right-field advantage at the adult level; this tendency, however, was not significant. None of these results was influenced by the use of different hands or eyes or to frequencies of commission of errors. The results suggested that a left-field advantage in speed of response to familiarized faces is found as early as 7 years of age and does not change appreciably thereafter. The finding of a significant left-field advantage for faces in the 7-year-old group represented an earlier age of left-field, right hemisphere lateralization for face stimuli than that previously obtained by other investigators. The failure to find over field differences with letter pairs was attributed to a possible tendency among subjects to process to letters visually (i.e., graphemically), a tendency which may have been more marked in the 7-year-old group due to the relative inexperience of children of this age with alphabetical material.

As an extension of previous studies, we reexamined the developmental change in trophic activity of chicken serum on chicken myogenic cells in vitro and attempted to elucidate it on the basis of possible changes in serum transferrin (Tf), the myotrophic activity of which depends both on its concentration and on the level of its iron-saturation. The myotrophic activity was found to be low until the second week in ovo, then to increase rather abruptly to a plateau at about the time of hatching, and then to decrease to the adult level. Determination of the concentration and level of iron-saturation of serum Tf suggested that the change in myotrophic activity was mainly caused by these two parameters, though another factor(s) may also be involved.

Glomerular filtration rate (GFR), estimated as clearance of inulin, and clearance of p-aminohippuric acid (CPAH) were measured in 32 unanaesthetized piglets 1–62 days of age. During this period of time, GFR increased from 0.27 to 0.59 ml/min/g kidney and CPAH increased from 1.02 to 1.72 ml/min/g kidney. At 8 weeks of age, GFR and CPAH equaled adult values. In addition, renal PAH extraction (EPAH) was estimated in 12 anaesthetized piglets aged 1–79 days. EPAH increased from 0.75 at birth to 0.86 (adult value) at 3 weeks of age. The result shows a postnatal increase in renal functions in piglets, but the development from birth to adult level was less pronounced than seen in other animal species.

There is an unequal distribution of interest between assessment of immunocompetence at the adult level following the administration of various agents/protocols and evaluation of immunocompetence postnatally subsequent to prenatal insult. This paper reviews the effects of dietary manipulation, selected pharmaceuticals, and certain environmental agents on the functional status of the postnatal immune system after in utero exposure to these agents and protocols. These data are discussed in light of what has also been observed for adult exposure to the same or similar experimental design. A discussion of congenital disorders of immunocompetence is also provided. Alteration in the development of postnatal immunocompetence following prenatal insult may manifest itself in several ways, some of which may reflect a permanent defect while others may be of a transient nature. In either instance, however, it behooves scientists in all arenas to (1) determine the precise nature and magnitude of such developmentally related immunologic deficits and (2) focus on the selection and standardization of the most relevant procedures to be employed in the assessment of immunocompetence.

The characteristic behavioral effects of d-lysergic acid diethylamide (LSD) in cats first appeared at approximately 25 days of age and increased rapidly in magnitude over the next 10 days. However, 25 day old kittens showed no tolerance to the repeated administration of the drug. While the behavioral response to the initial dose of LSD remained relatively constant between 35 and 112 days of age, the tolerance gradually became more pronounced throughout this time period, reaching an adult level of virtually complete tolerance at 112 days. These findings provide new insight into the nature of the relationship between the primary drug action and the development of tolerance, and suggest a new strategy for investigating the neural bases of tolerance, i.e., examining the neurochemical effects of repeated LSD administration in kittens during various stages of tolerance development.