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W H Wallace

Publications and source records attributed to W H Wallace.

At least 37 records · Page 2Linked to original sources
PubMed1999

With advances in medical imaging can the radiologist reliably diagnose Wilms' tumours?

AIM: To evaluate whether radiologists can accurately differentiate Wilms' tumours from other paediatric abdominal masses with renal involvement using modern imaging methods alone. METHODS: From February 1993 to June 1997, 23 patients presented to the Paediatric Oncology Service at The Royal Hospital for Sick Children, Edinburgh with an intra-abdominal mass which had renal involvement. Nine patients had Wilms' tumours, 12 had neuroblastomas, one patient had xanthogranulomatous pyelonephritis and there was a single case of a mesoblastic nephroma. In each case, two radiologists retrospectively reviewed the initial imaging examinations and independently reached a radiological diagnosis. RESULTS: The radiologists were concordant and reached the correct diagnosis in 20/23 cases (87%), unsure of the diagnosis in one case (4.3 %) and discordant in two cases (8.7 %). Radiologists should be aware that a mesoblastic nephroma can have identical imaging features to a Wilms' tumour. In most cases, ultrasound and a chest X-ray were sufficient to reach the correct diagnosis although computed tomography (CT) and magnetic resonance imaging were superior for demonstrating the relationship of the mass to the great vessels, retroperitoneum and spinal canal. Inferior vena cava invasion was strongly predictive of a Wilms' tumour. Displacement of the great vessels, extension of the mass across the mid-line, renal displacement and tumour calcification on CT were more suggestive of a neuroblastoma although these features were also seen in a significant number of patients with Wilms' tumours. Encasement of vessels by tumour, a paravertebral mass and spinal canal invasion were highly predictive of neuroblastoma. CONCLUSION: In this study, radiologists were accurate at diagnosing Wilms' tumours using modern imaging methods, however, care should be taken in children who are less than 1 year of age as a mesoblastic nephroma may have identical imaging characteristics.

Child↗
PubMed1999

Effects of a third intensification block of chemotherapy on bone and collagen turnover, insulin-like growth factor I, its binding proteins and short-term growth in children with acute lymphoblastic leukaemia.

Children with acute lymphoblastic leukaemia (ALL) have reduced bone turnover caused by the disease itself and early intensive chemotherapy, but the effects of later chemotherapy using different drug combinations are uncertain. We report here a longitudinal study on 9 children with ALL randomised to receive an additional third intensification block of chemotherapy, compared with 9 children receiving continuing chemotherapy over the same period. During third intensification, bone alkaline phosphatase, procollagen type I C-terminal propeptide, the carboxyterminal propeptide of type I collagen, procollagen type III N-terminal propeptide and lower leg length all decreased in response to dexamethasone, then returned to (but not beyond) baseline levels after dexamethasone was stopped and other drugs started. These changes were unrelated to circulating insulin-like growth factor (IGF)-I, IGF binding protein (IGFBP)-3 or IGFBP-2. In all children, bone alkaline phosphatase remained below the population mean throughout. We conclude that dexamethasone decreased bone and soft tissue turnover, probably through direct effects on target tissues. The postdexamethasone phase of third intensification and continuing chemotherapy had no major deleterious effect on collagen turnover, but there was evidence of continuing suboptimal bone mineralisation.

Adolescent↗
PubMed1999

Ovarian and uterine characteristics after total body irradiation in childhood and adolescence: response to sex steroid replacement.

OBJECTIVE: To study the effect of total body irradiation (14.4 Gray) in childhood and adolescence on ovarian and uterine characteristics, and to investigate the response to physiological sex steroid serum concentrations. DESIGN: All long term post-pubertal female survivors of total body irradiation who had been treated in paediatric centres in Scotland were identified. Their ovarian and uterine characteristics were studied. SETTING: Recruitment was from follow up oncology clinics. SAMPLE: Nine women were identified, eight of whom were assessed and five progressed to detailed investigation. A control population of 12 women treated for acute leukaemia, but not treated with total body irradiation, and five healthy women with no history of childhood malignancy were recruited as controls. METHODS: Ovarian function was determined by measurement of serum gonadotrophins and sex steroids. Uterine response to physiological sex steroid replacement was investigated in women with ovarian failure, and to endogenous sex steroid production in women with ovarian function by ultrasound scan. The physiological sex steroid replacement was achieved with transdermal oestradiol patches and self administered vaginal progesterone pessaries. MAIN OUTCOME MEASURES: Determination of ovarian function and uterine response to physiological sex steroid serum concentrations. RESULTS: Six of eight women treated with total body irradiation had ovarian failure; preservation of function was seen in two girls treated pre-pubertally who had biochemical evidence of incipient ovarian failure. Four women with ovarian failure had reduced uterine volume, undetectable blood supply and absent endometrium at baseline assessment; after three months of physiological sex steroid replacement treatment uterine blood supply and endometrial response were not significantly different from controls; uterine volume improved but remained significantly smaller than controls and correlated with age at total body irradiation. CONCLUSIONS: Ovarian failure after total body irradiation is common and risk relates to age at treatment. Physiological sex steroid replacement improved uterine measures and these women may benefit from assisted reproductive technology.

Adolescent↗
PubMed1998

Reduction mammaplasty using the inferior pedicle technique.

A retrospective study of 350 reduction mammaplasties by the inferior pedicle technique performed over a 3-year period allows a critical evaluation of postoperative complications and patient satisfaction. The procedure can be done in a timely manner on an outpatient basis and is applicable to breasts of different shapes and sizes. The rate of postoperative complications (5%) was comparable with previous studies. Patient satisfaction was high (98%), with near-total relief of preoperative symptoms. Concern about the resultant scars was low (2%) when the incisions followed the natural contour of the breast.

Adult↗
PubMed1998

Effects of intensive chemotherapy on bone and collagen turnover and the growth hormone axis in children with acute lymphoblastic leukemia.

To investigate the effects of disease and intensive chemotherapy on bone turnover and growth in children with acute lymphoblastic leukemia (ALL), a longitudinal prospective study was carried out in 22 children, aged 1.2-13.5 yr, enrolled in the Medical Research Council-funded randomized trial of childhood ALL treatment in the UK. We measured lower leg length and markers of bone formation [bone alkaline phosphatase (ALP) and procollagen type I C-terminal propeptide (PICP)], bone resorption [pyridinoline, deoxypyridinoline, and carboxyl-terminal telopeptide of type I collagen (ICTP)], soft tissue turnover [procollagen type III N-terminal propeptide (P3NP)], and the GH axis [IGF-I, IGF-binding protein-3 (IGFBP-3), IGFBP-2, and urinary GH] at 1- to 4-week intervals from diagnosis to week 27 of treatment. In addition, GH-binding protein was measured at diagnosis. At diagnosis, mean SD scores were: bone ALP, -1.84; PICP -1.77; pyridinoline, -1.42; deoxypyridinoline, -1.66; ICTP, -0.42; P3NP, +1.45; GH, +24.4; IGF-I, -1.70; IGFBP-3, -0.88; IGFBP-2, +2.42; and GH-binding protein, -0.69. Bone ALP, PICP, and IGFBP-3 were all correlated (P < or = 0.03). During induction and intensification, there was shrinkage of the lower leg, with decreases in PICP, pyridinoline, ICTP, and P3NP (P < 0.05), whereas IGF-I and IGFBP-3 increased (P < 0.05). After prednisolone was discontinued, bone ALP and collagen markers increased markedly (P < 0.01), but there was no significant change in IGF-I and IGFBP-3. In 12 children who received high dose i.v. methotrexate, postglucocorticoid increases in bone ALP and PICP were less, whereas those in ICTP and P3NP were greater, compared to levels in children who did not receive methotrexate (P < 0.05). We conclude that ALL itself caused GH resistance and low bone turnover. During early intensive chemotherapy, further suppression of osteoblast proliferation and osteoclast activity occurred, not mediated through the systemic GH axis, probably by the direct action of prednisolone on bone. The postglucocorticoid increase in bone turnover was also independent of the GH axis and was modulated by high dose i.v. methotrexate, which depressed osteoblast recovery and enhanced osteoclast activity.

Adolescent↗
PubMed1998

A morbidity study of former pentachlorophenol-production workers.

Pentachlorophenol (PCP) is a pesticide that was once widely used for wood preservation. Commercial PCP contained impurities including higher chlorinated dibenzo-p-dioxins (CDDs) and chlorinated dibenzofurans (CDFs). We investigated the effects of occupational exposure to PCP and its CDD and CDF contaminants on the skin, liver, porphyrin metabolism, and central and peripheral nervous systems. In 1986 we conducted a medical survey of 366 workers who had been engaged in the production of PCP at a single plant between 1938 and 1978. The referent group consisted of 303 workers from the same plant who were not exposed to these or related compounds. Exposure was determined from computerized personnel records. The medical survey included an administered questionnaire, medical record review, physical examination by dermatologists, internists, and neurologists, and analysis of 24-hr urine for quantitative porphyrins among other tests. In this paper we present the results of analyses of the general health, chloracne, and porphyrin metabolism end points. The general health status of PCP workers was similar to unexposed workers, but 17.8% of PCP workers had evidence of current or past chloracne. PCP workers with chloracne had significantly higher mean urinary excretion of coproporphyrins (117. 0 vs. 90.6 microg/24 hr) than unexposed workers after controlling for potential confounders. Workers with chloracne who had worked with both PCP and polychlorinated biphenyls had significantly higher mean urinary excretions of hepta-, penta-, and coproporphyrins than unexposed workers. We conclude that occupational exposure to PCP is associated with chloracne and biochemical abnormalities which may persist years after exposure.

Acne Vulgaris↗
PubMed1997

Effect of low dose oxandrolone and testosterone treatment on the pituitary-testicular and GH axes in boys with constitutional delay of growth and puberty.

OBJECTIVE: To investigate the effect of low dose oxandrolone and testosterone on the pituitary-testicular and GH-IGF-I axes. DESIGN: Prospective double-blind placebo-controlled trial. PATIENTS: Sixteen boys with constitutional delay of growth and puberty (CDGP) with testicular volumes 4-6 ml were randomized to 3 months treatment: Group 1 (n = 5), daily placebo: Group 2 (n = 5), 2.5 mg oxandrolone daily or Group 3 (n = 6), 50 mg testosterone monthly intramuscular injections with assessment (growth, pubertal development and overnight hormone profiles) at 0, 3, 6 and 12 months. MAIN OUTCOME MEASURES: LH and GH profiles (15-minute samples) were analysed by peak detection (Pulsar), Fourier transformation and autocorrelation. Testosterone levels were measured hourly and insulin, SHBG, IGF-I, and IGFBP-3 levels at 0800 h. Statistical analysis was by multivariate analysis of variance for repeated measures. RESULTS: LH and testosterone parameters increased significantly with time in all 16 (LH AUC, P < 0.001; peak amplitude, P = 0.02; number of peaks, P = 0.02; testosterone AUC, P = 0.02; morning testosterone, P = 0.002). In Group 2, however, LH and testosterone parameters decreased at 3 months followed by a rebound increase at 6 and 12 months. SHBG levels were markedly reduced at 3 months (P = 0.006) and a wider range of dominant GH frequencies was present although GH AUC was not increased until 6 months, with an increase in GH pulse frequency but not amplitude. IGF-I levels were increased at both 3 and 12 months. In Group 3, pituitary-testicular suppression was not apparent, but GH levels increased with an increase in GH amplitude at 3 and 12 months. CONCLUSION: Oxandrolone transiently suppressed the pituitary-testicular axis and altered GH pulsatility. Testosterone increased GH via amplitude modulation.

Adolescent↗
PubMed1997

Short-term changes in urinary growth hormone excretion and lower leg length in healthy children.

To investigate any association between changes in lower leg length (LLL) and urinary growth hormone (uGH) excretion, 4 prepubertal children supplied daily 12-hour overnight urine samples and had daily knemometry performed for 4 weeks. The mean daily and weekly LLL velocity (LLLV) of the group was (0.08 mm/day (95% CI 0.01-0.18) and 0.52 mm/week (range 0.38-0.78), respectively. The mean uGH excretion was 8.9 ng/l (CI 3.7-13.3), and the mean intrasubject coefficient of variation of uGH was 55% (range 32-93). The tallest subject who also had the highest LLLV excreted the least amount of uGH (mean 3.7 ng/l, CI 2.9-4.5). No temporal relationship was evident between daily uGH excretion and LLLV. There was no evidence of any association between amount of uGH excreted and LLLV. There remains some doubt on the usefulness of uGH measurement as the sole predictor of normal GH production.

Child↗
PubMed1997

An anthropometric study of children during intensive chemotherapy for acute lymphoblastic leukaemia.

In order to study the short-to medium-term effects of cytotoxic chemotherapy (CT) for acute lymphoblastic leukaemia (ALL) on growth in prepubertal children, a prospective study of weight (Wt), height (Ht), sitting height (SH) and body mass index (BMI) was performed in 31 children receiving intensive CT for ALL. Two pubertal children, 1 child with Down's syndrome and 3 children who had cranial irradiation were excluded from the analysis. Monthly measurements were presented as change in standard deviation scores from baseline (delta SDS). The median age at diagnosis was 4.4 years (range, 1.1-14). The median duration of study per subject was 18 months (3-24). The median delta SDS-Ht reached a nadir of -0.35 at 6 months after the start of CT (p = 0.001, Wilcoxon signed rank test); the median delta SDS-SH was -0.55 at 3 months (p = 0.02); the median delta SDS-Wt and delta SDS-BMI increased at 2 months to 0.15 (p = 0.03) and 0.5 (p = 0.002), respectively. The median delta SDS-BMI was also elevated at 10 months (0.75, p = 0.01) reflecting the relative delay in recovery of Ht-SDS in comparison to Wt-SDS. The median SH:Ht ratio, a measure of disproportion, was reduced at 3 months (delta SH:Ht ratio, -0.01, p = 0.009). No significant changes in Ht-SDS, BMI-SDS or SH:Ht from baseline were evident at the end of the CT. Cytotoxic CT for ALL in childhood has a significant adverse effect on growth, but there is some evidence for recovery before the end of CT.

Adolescent↗
PubMed1996

Biochemical markers of bone turnover.

Three studies to evaluate procollagen type I C-terminal propeptide, type I collagen cross-linked telopeptide and bone alkaline phosphatase (BALP) in the assessment of bone turnover and growth in children are presented. (1) In 50 short normal children treated with placebo or growth hormone, delta BALP after 3 months of treatment was highly correlated with height velocity response after 1 year (r = 0.67, p < 0.0001). (2) In 12 children with acute lymphoblastic leukaemia, marked changes in collagen peptides, BALP, and lower leg length velocity were seen during the first 6 months of chemotherapy. Suppression occurred during induction and the two intensification phases, with catch-up during the intervening phase (paired t-tests, p < 0.001). (3) Fourteen babies (birthweight < 1,500 g) treated with high-dose dexamethasone for bronchopulmonary dysplasia were compared with 25 non-steroid-treated babies < 1,500 g. Both collagen peptides decreased rapidly and dramatically (mean decreases 41-68%) after dexamethasone was started, accompanied by weight loss and lower leg shrinkage and followed by recovery during steroid weaning.

Alkaline Phosphatase↗
PubMed1996

Late effects of antineoplastic therapy in childhood on growth and endocrine function.

The major challenge for this generation of children's cancer specialists is to sustain the significant improvement in survival rates, while at the same time minimising treatment-induced late adverse effects. The available evidence suggests that, following first line treatment of acute lymphoblastic leukaemia (ALL), current treatment regimens used in the UK are unlikely to cause sterilisation in either gender. For men who are treated for Hodgkin's disease with 6 or more courses of antineoplastic therapy, azoospermia is the rule. Childhood studies have clearly indicated that the prepubertal testis is not protected from antineoplastic therapy that is potentially sterilising. The interpretation of tests of ovarian function in women treated for cancer in childhood is difficult, but there is increasing evidence of ovarian dysfunction in children treated for Hodgkin's disease. Reassuringly there is no evidence of an increased risk of miscarriage following antineoplastic therapy or an increased number of abnormalities in the offspring. The growth patterns and requirement for growth hormone replacement therapy in children treated for ALL are still unclear. There is good evidence that the intensity and duration of combination cytotoxic antineoplastic therapy received by children with ALL influences the pattern of growth, and that adjuvant antineoplastic therapy for children treated for a brain tumour is an important factor in final height achieved. A child who has been treated for cancer should not be discharged from follow-up. Late effects may have significant implications in later life, and an understanding of these effects is essential to enable balanced decisions to be made regarding the benefits and risks of currently available agents.

Adult↗
PubMed1995

Degree of activation of the pituitary-testicular axis in early pubertal boys with constitutional delay of growth and puberty determines the growth response to treatment with testosterone or oxandrolone.

Early pubertal boys (testicular volume, 4-6 mL) with constitutionally delayed growth and puberty were randomized to 3 months of treatment after a baseline 12-h overnight hormone profile: group 1 (n = 5), daily placebo; group 2 (n = 5), 2.5 mg oxandrolone daily; or group 3 (n = 6), 50-mg testosterone monthly im injections. LH and GH profiles (15-min samples) were analyzed by peak detection (Pulsar), Fourier transformation, and autocorrelation. FSH and testosterone levels were measured hourly, and insulin, sex hormone-binding globulin, insulin-like growth factor-I, and insulin-like growth factor-binding protein-3 levels were determined at 0800 h. Multiple regression was used to analyze the response to treatment (growth) with respect to baseline features. Endocrine variability was marked. Profiles ranged from unreactive to well established LH pulsatility and adult testosterone levels. The areas under the curve (AUC) for LH, FSH, and testosterone ranged 10-fold (4.4-46.3 IU/L.h), 8-fold (7.9-63.4 IU/L.h), and 45-fold (3.6-161.7 nmol/L.h), respectively. The growth response was individually varied, but significantly increased 0-6 months in the active treatment groups. Age, testicular volume, and LH AUC interacted significantly (r2 = 0.95; P < 0.05). Allowance for these produced a highly significant treatment effect (P = 0.006). Age, testicular volume, LH AUC, and testosterone AUC, but not treatment, significantly increased growth by 0-12 months (r2 = 0.88; P < 0.05). We demonstrate a spectrum of activation of the reproductive axis despite tight clinical staging. This, and not GH status at treatment commencement, influenced the growth response.

Adolescent↗
PubMed1994

Radiation and neuroregulatory control of growth hormone secretion.

OBJECTIVE: Cranial irradiation frequently results in growth hormone (GH) deficiency. Patients with radiation-induced GH deficiency usually remain responsive to exogenous growth hormone releasing hormone, implying radiation damages the hypothalamus rather than the pituitary. Little is known about the effect of cranial irradiation on the neuroendocrine control of GH secretion. This study was to determine the effect of cranial irradiation on somatostatin tone. DESIGN: Somatostatin tone was examined by manipulating cholinergic tone in young adults with radiation-induced GH deficiency and a control population. Each individual underwent three separate studies: the GH response to 100 micrograms GHRH-(1-29)-NH2 was assessed alone, and 60 minutes after pyridostigmine or pirenzepine. PATIENTS: Eight young male adults with radiation induced GH deficiency following treatment in childhood for a brain tumour or acute lymphoblastic leukaemia, and ten healthy adult men were studied. MEASUREMENTS: Serum growth hormone was measured at 15-minute intervals throughout each of the three study periods. RESULTS: One of 10 controls and four of eight irradiated subjects had a peak GH level to GHRH analogue of less than 20 mU/l. After pretreatment with pyridostigmine, all subjects except one irradiated subject had a peak GH level of greater than 20 mU/l. Pretreatment with pyridostigmine and pirenzepine significantly modified the GH response to GHRH analogue within both groups (P < 0.0005). Pretreatment with pyridostigmine significantly enhanced the GH response to GHRH analogue (median (range) area under the curve, 9029 (1956-20940) mU/l/min in controls vs 1970 (628-3608) mU/l/min in the irradiated group) compared with GHRH analogue alone (1953 (512-16140) mU/l/min in control group vs 997 (266-3488) mU/l/min in the irradiated group). Pretreatment with pirenzepine significantly attenuated the GH response to GHRH analogue (552 (64-1274) mU/l/min in controls vs 305 (134-2726) mU/l/min in irradiated group). Between the groups there was no significant difference in GH area under the curve (AUC) after GHRH analogue alone. There was a significantly (P = 0.0014) greater increment of GH secretion after pyridostigmine and GHRH analogue compared with GHRH analogue alone (difference in AUC of pyridostigmine+GHRH analogue and GHRH analogue alone 6348 (696-12856) mU/l controls vs 542 (120-1340) mU/l in the irradiated group) and significantly (P = 0.033) greater suppression of GH secretion after pirenzepine and GHRH analogue compared with GHRH analogue alone (difference in AUC of GHRH analogue alone and pirenzepine+GHRH analogue 1644 (222-15205) mU/l in controls vs 479 (469-1623) mU/l in the irradiated group) in the control population compared with those who had received cranial irradiation in childhood. CONCLUSIONS: These data suggest that cranial irradiation reduces but does not abolish somatostatin (SRIH) tone and also reduces endogenous GHRH secretion. Although SRIH tone is reduced, it can be increased by cholinergic manipulation and is therefore not irreversibly fixed. This has possible implications if GHRH analogues were used to treat children with radiation induced GH deficiency.

Adult↗
PubMed1994

Biodegradation of 2-nitrotoluene by Pseudomonas sp. strain JS42.

A strain of Pseudomonas sp. was isolated from nitrobenzene-contaminated soil and groundwater on 2-nitrotoluene as the sole source of carbon, energy, and nitrogen. Bacterial cells growing on 2-nitrotoluene released nitrite into the growth medium. The isolate also grew on 3-methylcatechol, 4-methylcatechol, and catechol. 2-Nitrotoluene, 3-methylcatechol, and catechol stimulated oxygen consumption by intact cells regardless of the growth substrate. Crude extracts from the isolate contained catechol 2,3-dioxygenase and 2-hydroxy-6-oxohepta-2,4-dienoate hydrolase activity. The results suggest that 2-nitrotoluene is subject to initial attack by a dioxygenase enzyme that forms 3-methylcatechol with concomitant release of nitrite. The 3-methylcatechol is subsequently degraded via the meta ring fission pathway.

Biodegradation, Environmental↗
PubMed1993

Ovarian function following the treatment of childhood acute lymphoblastic leukaemia.

Ovarian function was assessed in 40 long term survivors who had received standard United Kingdom Acute Lymphoblastic leukaemia (UKALL) protocols and were in first clinical and haematological remission. A menstrual and pregnancy history was taken (median age at assessment: 18.8 (12-34.7) years) and the acquisition of adult secondary sexual characteristics confirmed in each patient. Basal bloods were taken for follicle stimulating hormone (FSH), luteinizing hormone (LH), and serum oestradiol estimations. Serum progesterone concentration was measured in those patients who were in the luteal phase of their menstrual cycle at assessment. In addition, menstrual cycle profiles of salivary progesterone concentrations were derived from daily samples in 12 patients. All patients achieved adult sexual development; median age at menarche was early at 12.4 (9.0-14.6) years and 37 of them have regular menses. Ten patients have had 14 live births, and evidence of ovulation was seen in a further 11 patients assessed in the luteal phase of the menstrual cycle. Four patients had damaged ovaries, two of whom show evidence of ovulation; three of the four received craniospinal irradiation and one received cyclophosphamide as part of her chemotherapy regimen. None of these patients has yet developed total ovarian failure or required sex steroid replacement therapy. The medium term outlook for ovarian function is good for the majority of childhood ALL survivors. The spinal component of craniospinal irradiation is a major risk factor for ovarian damage, and cyclophosphamide may be a contributory factor. A premature menopause remains a possibility if significant follicular depletion has occurred at the time of cytotoxic treatment.

Adolescent↗
PubMed1993

Adrenocorticotrophin and cortisol secretion in children after low dose cranial irradiation.

OBJECTIVE: We investigated the effect of low dose cranial irradiation (18-24 Gy) on spontaneous ACTH and cortisol secretion in children. DESIGN: We analysed 24-hour plasma ACTH and cortisol profiles sampled at 20-minute intervals. PATIENTS: Twenty long-term survivors of acute lymphoblastic leukaemia were studied and results compared with those in 14 normal children. MEASUREMENTS: ACTH and cortisol profiles were analysed by Fourier transformation and spectral analysis of stationarized data, autocorrelation and coherency analysis. RESULTS: The normal circadian rhythms of ACTH and cortisol were preserved in the children after cranial irradiation. The median 0900 h and midnight values were 1.50(0.8-6.4)pmol/l and 1.0(0.6-3.7)pmol/l respectively for ACTH and 282(48-1913)nmol/l and 57.5(44-637)nmol/l respectively for cortisol, and were not significantly different from those in the normal group. Fourier transformation revealed dominant periodicities for ACTH at 0.7-1.1 h, equivalent to 22-34 ACTH secretory bursts per 24 hours, and for cortisol at 0.7-1.1 h and 2-4.8 h. Similar results were found in the normal group. Coherency analysis indicated a significant shared periodicity of 0.7-1.2 h in nine children, corresponding to 20-34 related secretory bursts in 24 hours for ACTH and cortisol. After pooling the coherency spectra in the cranially irradiated group, comparison with the pooled data from the normal group revealed no significant difference between the two groups in the relationship between the two hormones. CONCLUSION: No significant disruption of spontaneous ACTH or cortisol secretion, either in the amount or pattern of hormones secreted, was found in children after low dose cranial irradiation (18-24 Gy).

Adolescent↗