Brain perfusion assessed by 99mTc-ECD SPECT imaging in pediatric patients with neurally mediated reflex syncope.

BACKGROUND: The involvement of cardiogenic and neurogenic mechanisms in neurally mediated reflex syncope is well documented. In our previous studies in patients with neurally mediated reflex syncope, we have found evidence for differential regulation of the noradrenergic receptors in tilt-positive and tilt-negative patients. The present work concentrates on the observations of differences in regional brain perfusion using brain SPECT via injecting the patient at the completion of the tilt test. METHODS AND RESULTS: The following study was designed to assess the reduction and regional differences in cerebral blood flow by means of SPECT using technetium-99m labeled V-oxo-1,2-N1ethylenedylbisl-cysteine diethylester (ECD) in patients with an injection during tilt testing. Twenty patients with NMS were included in the study with a mean age of 12.2 years (age range; 8-16 years). HUT was positive in 10 patients and negative in 10 patients. When tilt (+) and tilt (-) were evaluated together, regional cortical/cerebellum ratios were ranging from 0.85 to 1.25 in different cortical areas with highest variability of perfusion index in left frontoparietal cortex. The lowest perfusion index values were observed in the left anterior frontal region followed by the left prefrontal-frontoparietal-anterior, parietal-orbito frontal, and anterior temporal regions where perfusion is predominantly supplied via the anterior and middle cerebral arteries, while these differences did not reach statistical significance in a single dominant region compared to the other regions examined using ANOVA (P > 0.05) with this sample size. Decreases in [99mTc]ECD uptake were more widespread regionally on the left hemisphere than were decreases in right side of the brain. However when tilt- and tilt+ groups were compared, perfusion was significantly lower in the right periinsular posterior parietal and temporal regions (P < 0.05) in tilt + group. CONCLUSION: These tilt induced regional differences in brain perfusion suggest the distinct roles of middle cerebral artery dominant territory-related vasodepressor compensation mechanisms in neurally mediated reflex syncope phenomena where cerebral lateralization of cardiac control and insular ischemia may play an important role.

Abnormality of the left ventricular sympathetic nervous function assessed by I-123 metaiodobenzylguanidine imaging in pediatric patients with neurocardiogenic syncope.

The purpose of this study was to assess the left ventricular sympathetic nervous system function in the patients with neurocardiogenic syncope (NCS) using I-123 metaiodobenzylguanidine (MIBG) imaging of the heart, and to compare the plasma noradrenaline (NA) and MIBG results of tilt positive and tilt negative patients following a head-up tilt test (HUT). The study included 30 patients. Their physical and laboratory examinations did not show a pathology that may be the cause of their syncope. HUT test was positive in 13 patients and negative in 17 patients. Plasma NA concentrations were higher in the HUT positive than the HUT negative group at the beginning and at the 10th minute of the test. Specific I-123 MIBG uptake assessed as the cardiac to mediastinal activity ratio in the delayed image was significantly higher in HUT positive group. The higher levels of MIBG uptake and plasma NA observed in HUT positive patients may reflect the greater capacity of NA storage in cardiac adrenergic neuronal tissue in patients with NCS. The results of this study support the critical role of autonomic nervous system in the pathophysiology of NCS and the excessive sympathetic nervous stimulation as the trigger of paradox reflex.

Is increased D2 receptor availability associated with response to stimulant medication in ADHD.

The purpose of this study was to estimate striatal dopamine (D2) receptor availability in non-drug treated children with attention-deficit-hyperactivity disorder (ADHD) before and after methylphenidate therapy, and to examine correlations between severity of symptoms and response rates to stimulant medication with levels of striatal D2 receptor binding. Nine children (six males, three females; mean age 9.8 years, SD 2.3 years) with ADHD participated. All underwent iodobenzamide (123I IBZM) brain SPECT within 2 hours following intravenous injection of 123I IBZM before and 3 months after methylphenidate therapy. A semiquantitative approach was used to generate indices of specific D2 receptor binding in the basal ganglia. Specific binding ratios at baseline were higher than the previously reported specific binding values obtained in studies using young healthy adults. D2 availability reduced significantly (paired t-test,p<0.05) as a function of methylphenidate therapy in patients with ADHD in all four regions of the striatum. When the relation between therapy response and D2 availability was investigated, we observed that the higher the baseline D2 levels were, the higher the response rate was (detected as the percentage reduction of hyperactivity scores and Conners Teacher Rating Scale scores), while no such trend was observed between the initial D2 binding levels and the response in attention-deficit scores. Results indicate that in non-drug treated children with ADHD, higher D2 receptor availability is observed at baseline which is down-regulated back to reported near-normal values after methylphenidate therapy. The effect of methylphenidate on D2 receptor levels in patients with ADHD is similar to that observed in healthy adults; a down-regulation phenomenon within 0 to 30%. In addition, initially higher values of D2 availability seem to indicate better response to methylphenidate therapy in ADHD.

Increased accumulation of Tl-201 in monostotic Paget's disease of the patella: evaluation with quantitative analysis.

Monostotic Paget's disease of the patella was detected with Tc-99m MDP and Tl-201 scans. Diffuse intense uptake of MDP in the left patella was observed on the blood-pool and late phases of the bone scan. Tl-201 imaging was performed to differentiate a malignant process and showed diffuse marked accumulation at the same site. Semiquantitative analysis of the patella region on both Tc-99m MDP and Tl-201 scans did not support a diagnosis of cancer. Radiographs showed the features of Paget's disease of the bone. Findings of a pathologic evaluation were compatible with the diagnosis of osteitis deformans. This case represents the unusual skeletal involvement of monostotic Paget's disease of the bone in the patella. Tl-201 accumulation in the Paget's lesion was suggested to be caused by increased metabolic activity of the lesion but was not indicative of a malignant process.

Tc-99m HMPAO brain perfusion imaging in young Down's syndrome patients.

Down's syndrome (DS) is characterized by moderate mental retardation and a variety of abnormalities involving multiple organ systems. There is a high incidence of Alzheimer's disease (AD) type dementia beyond the age of 35. In this study, single photon emission computed tomography (SPECT) brain perfusion imaging of young Down's syndrome patients was performed to define the perfusion pattern. Tc-99m HMPAO brain perfusion SPECT was performed on 17 young DS patients, aged 3-24 years (mean: 10.9+/-5.9 years). None of the patients had dementia symptoms. Brain perfusion scans were acquired 15 min after i.v. injection of 12 MBq/kg of Tc-99m HMPAO using a single head rotating gamma camera. Images were analyzed visually and semiquantitatively by defining side-to-side asymmetry index. Nine DS cases showed normal brain perfusion. Eight of the 17 cases revealed mostly unilateral parieto-temporal, parieto-occipital and frontal hypoperfusions. The side-to-side asymmetry indices for these visually interpreted regional brain perfusion abnormalities ranged from 6 to 15%. These findings revealing mostly unilateral parieto-temporal and frontal hypoperfusions may not be considered as predictive patterns of dementia related Alzheimer type perfusion deficits in DS. However, such findings may connect to other functional imaging studies related to the higher cortical dysfunction in mental retardation.

Stress hyperglycemia in minimally invasive surgery.

This study examined the selected hormonal responses to, and hormone-mediated glucose metabolism during minimally invasive surgery in, patients undergoing laparoscopic cholecystectomy for symptomatic gallstone disease. Thirty-two patients with symptomatic gallstone disease were included in this study and scheduled for open or laparoscopic procedure in a randomized trial. Results are expressed as mean and standard error of the mean. Statistical evaluations were performed with Mann-Whitney U and Wilcoxon signed-rank tests. Blood cortisol, glucagon, insulin, and glucose concentrations were measured immediately in the preoperative period and 6 h after surgery. Blood cortisol, glucagon, and glucose concentrations increased significantly after open and minimally invasive surgery, while insulin levels and the insulin:glucagon ratio remained unchanged. The rise of glucagon and cortisol values was found to be significantly higher in the postoperative period of the open procedure, than in the laparoscopic approach. However, in the patients who underwent open surgery, the increase in glucose concentrations was not significantly higher in the postoperative period. Surgery-induced hormonal effects on the islets increase glucagon and suppress insulin secretion. The glucagon-mediated increase in hepatic glucose production is excluded by the posttraumatic insulin levels from the insulin-sensitive tissues. A bihormonal setting favors a greater rate of hepatic glucose production in both open and laparoscopic surgery. Hormonal changes do reflect the degree of surgical stress, but their metabolic consequences are not parallel to the grade of surgical trauma in minimally invasive surgery.

Evaluation of renal function following treatment with extracorporeal shock wave lithotripsy (ESWL): the use of whole-kidney, parenchymal and pelvic transit times.

The aim of this prospective study was to assess the efficacy of using whole-kidney, mean parenchymal and pelvic transit times to evaluate renal function following treatment with extracorporeal shock wave lithotripsy (ESWL). Fifteen patients were evaluated 24-48 h before and after ESWL therapy using 99Tcm-DTPA renal scintigraphy. Using deconvolution analysis, whole-kidney, mean parenchymal and pelvic transit times were calculated and the pre-ESWL values were compared with the post-ESWL values. In both kidneys, there were no significant changes in the glomerular filtration rate or relative renal uptake when compared with the pre-ESWL values. The mean whole-kidney transit time of the tracer did not change significantly during the post-ESWL period. In the treated kidney, the mean post-ESWL parenchymal transit time was significantly increased (P < 0.05), while the mean pelvic transit time was significantly decreased (P < 0.05). In the untreated kidney, there were no significant changes in any of these parameters. We conclude that the dual use of parenchymal and pelvic transit times is more sensitive than the mean whole-kidney transit time and other measures, such as glomerular filtration rate and relative renal uptake, for the assessment of outcome of therapy and other related post-ESWL changes.

Assessment of brain perfusion by 99mTc-HMPAO SPECT in akinetic mutism due to high-dose intravenous methotrexate therapy.

Chemotherapy of the central nervous system may cause neurotoxicity in children with acute lymphocytic leukemia. We evaluated regional blood flow in a 6-year-old child presenting with akinetic mutism, using 99mTc-HMPAO single photon emission tomography (SPECT) following high-dose intravenous methotrexate therapy. While findings in X-ray computerized tomography were decreased density in bilateral basal ganglia and thalamic nuclei with diffusely decreased attenuation of the periventricular white matter, a global, frontal dominant profoundly abnormal perfusion pattern involving both gray and white matter was observed in the SPECT study. Treatment of the central nervous system with high dose intravenous chemotherapy may cause profound abnormalities in white and gray matter blood flow and early assessment of the neurotoxicity may be identified by 99mTc-HMPAO SPECT in the pediatric age group.

The association of chronic urticaria and angioedema with autoimmune thyroiditis.

BACKGROUND: An increased frequency of autoimmune thyroiditis is seen in patients with chronic urticaria and angioedema (CUA) and it has been hypothesized that autoimmunity may be playing a role in the pathogenesis of CUA. The aim of this study was to learn the extent of autoimmune thyroid disease in a series of patients who presented with CUA. METHODS: Thyroid function tests and thyroid autoantibodies were measured by radioimmunoassay and immunoradiometric assay respectively in 94 CUA patients and 80 age- and sex-matched healthy volunteers. RESULTS: Eleven patients (11.7%) were found to have thyroglobulin antibodies (TGA) and nine patients (9.57%) thyroid microsomal (TMA) titers ranging from 150 to 1340.37 and from 165.73 to 8000 IU/mL respectively. Both antibodies were detected in three control cases (3.7%). The association was statistically significant (P < 0.01). Six of 11 patients had thyroid dysfunction and the other five cases were euthyroid. CONCLUSIONS: Our results justified the use of TMA and TGA for the early diagnosis of autoimmune thyroiditis in combination with CUA. The higher frequency of these antibodies in our patients, along with results from previously published data, suggest that this entity may reflect an autoimmune basis in some CUA patients. Thyroid function tests are not enough to rule out thyroid disease, and thyroid antibody tests should be carried out in all patients with CUA.

Comparison of indium-111 octreotide and thallium-201 scintigraphy in patients mammographically suspected of having breast cancer: preliminary results.

Indium-111 octreotide and thallium-201 scintigraphic studies were compared in 21 patients (16 with palpable and five with non-palpable lesions) suspected of having breast malignancies on the basis of mammography. Early (15 min) and late (3 h) 201Tl (111 MBq) and 4-h and 24-h 111In-octreotide (111-148 MBq) static planar anterior images (matrix 256 x 256) were obtained on separate days. Images were evaluated both visually and quantitatively. Biopsy was performed following the imaging studies. Histopathology revealed 17 breast carcinomas (15 cases of invasive ductal carcinoma, one mucinous adenocarcinoma and one intraductal carcinoma) and four benign breast lesions (two fibroadenomas, one abscess and one case of fat necrosis). The means histopathological tumour size (mean largest diameter) was 3.38 +/- 1.9 cm. 111In-octreotide detected 16 of the 17 breast cancers (94%) while 201Tl detected 13 of them (76%). Both 111In-octreotide and 201Tl missed one non-palpable carcinoma showing only an isolated cluster of microcalcifications on mammography. The smallest tumour size detected by both agents 1.5 x 1.5 cm. Of the four benign lesions, only the breast abscess revealed both 201Tl and 111In-octreotide uptake. 111In-octreotide scan also showed tracer uptake in five of the six patients with histologically proven axillary metastases, while four of these six patients showed 201Tl uptake. The tumour/background (T/B) ratios of late 111In-octreotide and 201Tl images were 1.71 +/- 0.38 and 1.46 +/- 0.30 respectively (P = 0.039). In this preliminary study, 111In-octreotide yielded more favourable results than 201Tl in the detection of breast carcinomas. However, the diagnostic efficacy of 111In-octreotide imaging needs to be investigated in larger patient series.

Tl-201 scintigraphy, mammography and ultrasonography in the evaluation of palpable and nonpalpable breast lesions: a correlative study.

PURPOSE: To determine the feasibility of Tl-201 as a tumor localizing agent in palpable and nonpalpable breast lesions, in comparison with mammography and ultrasonography (US), and to evaluate the contribution of these modalities to each other in obviating biopsy. MATERIALS AND METHODS: Seventy-two palpable and nonpalpable breast lesions were prospectively classified as benign, indeterminate, or malignant according to the sonographic and mammographic criteria and were further analyzed with Tl-201 scanning. These classifications were compared with biopsy results. The sensitivity, specificity, accuracy, false positive and false negative rates (FPR, FNR), negative and positive predictive values (npv, ppv) were calculated for each individual modality and combination of modalities to evaluate the contribution of these three techniques to each other. RESULTS: Of 72 lesions 52 were histologically malignant and 20 were benign. Overall, mammography was the most sensitive (92%) and Tl-201 was the most specific (75%) of the three modalities. Mammography + Tl combination was the most specific (90%) and accurate (97%) of dual combinations. In mammographically or sonographically indeterminate cases, Tl-201 was much more specific (75% versus 37% for mammography and US) and more accurate (82% versus 36% for mammography and 54% for US) than the other two modalities, and mammography + Tl combination was significantly superior to other dual combinations (87% specific and 91% accurate). Use of Tl-201 scanning as an adjunct to mammography + US combination increased the specificity, ppv, and accuracy rates overall, particularly in mammographically or sonographically indeterminate cases. CONCLUSIONS: In mammographically and sonographically indeterminate breast lesions thallium scanning may be offered as a third step of investigation to obviate biopsy.

Comparison of sputum and serum eosinophil cationic protein (ECP) levels in nonatopic asthma and chronic obstructive pulmonary disease.

The aim of the present study was to investigate whether sputum eosinophil cationic protein (ECP) concentrations could be a useful marker in the differential diagnosis between intrinsic asthma and chronic obstructive pulmonary disease (COPD). For this purpose total blood eosinophil counts were obtained and concentrations of serum and sputum ECP from 10 nonatopic asthmatics with a mild attack and 9 COPD patients with acute exacerbation were measured by radioimmunoassay. Mean serum ECP concentration was 54.3 +/- 23.0 micrograms/L in the asthmatic group and 83.3 +/- 79.2 micrograms/L in the COPD group (p: n.s.). In the group of asthmatics mean sputum ECP level was 984.5 +/- 1245.5 micrograms/L/g sputum and in the COPD group it was 417.5 +/- 363.5 micrograms/L/g sputum. There was no significant difference in sputum ECP levels between patients with asthma and COPD. We conclude that neither sputum nor serum ECP levels are useful markers in differential diagnosis of asthma attack and acute exacerbation of COPD.

201Tl scintigraphy in the evaluation of palpable and nonpalpable breast lesions: correlation with mammography and ultrasonography.

AIM: Our goal was to determine the clinical usefulness of Tl-201 to identify breast cancer in patients with suspicious breast lesions on clinical examination, and/or abnormal radiologic (mammography and/or ultrasonography) findings. METHODS: Tl-201 scintigraphy were performed in sixty-eight patients with 70 breast abnormalities (51 palpable, 19 nonpalpable) and compared with mammography and ultrasonography (US). Early (15 min) and late (3 h) images of the breasts were obtained following the injection of 111 MBq (3 mCi) of Tl-201. Visual and semiquantitative interpretation was performed. RESULTS: Final diagnosis confirmed 52 malignant breast lesions and 18 benign conditions. Tl-201 visualized 47 of 52 (90%) overall malignant lesions. Thirty-eight of 40 (95%) palpable and 9 of 12 (75%) nonpalpable breast cancers were detected by Tl-201 scintigraphy. The smallest mass lesion detected by Tl-201 measured 1.5 x 1.0 cm. Eleven breast lesions were interpreted as indeterminate by mammography and/or sonography. Tl-201 scintigraphy excluded malignancy in 7 of 8 (88%) patients with benign breast lesions interpreted as indeterminate. Five of the 18 (28%) benign breast lesions showed Tl-201 uptake. None of the fibroadenoma and fibrocystic changes accumulated Tl-201. Tl-201 scintigraphy, mammography and ultrasonography showed 90%, 92%, 85% overall sensitivity and 72%, 56%, 61% overall specificity respectively. Twenty-one of the 28 (75%) axillary nodal metastatic sites were also detected by Tl-201. In malignant and benign lesions, early and late lesion/contralateral normal side (L/N) ratios were 1.58 +/- 0.38 (mean +/- SD) and 1.48 +/- 0.32 (p > 0.05), 1.87 +/- 0.65 and 1.34 +/- 0.20 (p < 0.05) respectively. The mean early and late L/N ratios of malignant and benign groups did not show statistical difference (p > 0.05). CONCLUSION: Overall, Tl-201 scintigraphy was the most specific of the three methods and yielded favourable results in palpable breast cancers, while it showed lower sensitivity in nonpalpable cancers and axillary metastases. Combined use of Tl-201 scintigraphy with mammography and US seems to be useful in difficult cases, such as dense breasts and indeterminate breast lesions.

The changes in serum type I and III procollagen, insulin-like growth factor-I and insulin-like growth factor binding protein-3 levels in children with chronic renal failure.

Serum levels of carboxyterminal propeptide of type I procollagen (PICP) and aminoterminal propeptide of type III procollagen (PIIINP) can be used as markers of bone formation and the evaluation of children with growth disorders. We measured the serum levels of these collagens by radioimmunoassay (RIA), insulin-like growth factor I (IGF-I) (by immunoradiometric assay) and insulin-like growth factor binding protein-3 (IGFBP-3) (by RIA) levels in 24 children aged between 4 and 14 years with chronic renal failure (CRF) (n = 12 dialysis, n = 12 non-dialysis) and 12 age-matched healthy controls, to find out whether these parameters have a prognostic or therapeutic value on monitoring of growth retardation in CRF. Mean serum IGFBP-3 and PIIINP levels in the dialysis patients were higher than the control group, the difference between the groups was statistically significant (P < 0.05). It seemed that the pubertal stage of the patients did not affect the levels of PICP, PIIINP, and IGFBP-3 while serum IGF-I levels in pubertal patients were significantly higher than those in prepubertal patients (P < 0.001). There was no significant correlation between PICP and PIIINP in any patients. Neither PICP nor PIIINP correlated with height z-score, bone age, IGF-I, or IGFBP-3. It was concluded that the increased serum IGFBP-3 and PIIINP levels in chronic renal disease are poor prognostic indicators leading to progressive renal failure and end-stage renal disease (ESRD). Further investigations into the effects of these collagens on growth failure associated with CRF are needed.

Effects of inhaled steroid treatment on serum eosinophilic cationic protein (ECP) and low affinity receptor for IgE (Fc epsilon RII/sCD23) in childhood bronchial asthma.

Serum eosinophilic cationic protein (ECP) and soluble low affinity receptor for IgE (Fc epsilon RII/sCD23) concentrations were measured in relation to symptom-medication scores, pulmonary function, and total IgE levels in 27 chronic allergic asthmatic children (17 boys, 10 girls), mean age 10.8 years, before and at the end of a three month inhaled corticosteroid (budesonide) treatment period. Serum ECP and sCD23 concentrations were also measured in age matched non-asthmatic controls with allergic rhinitis. All asthma patients had significantly higher serum ECP and sCD23 than the controls, whereas the mean serum IgE was not different. No correlation between total IgE concentrations and serum sCD23 could be detected in either group. At the end of the treatment period, symptom-medication scores and pulmonary function improved. Serum ECP and sCD23 concentrations were reduced; however, total IgE values did not change significantly. A significant relation was found between the improvement of symptom-medication scores and fall in both sCD23 and ECP concentrations. Although there was a significant correlation of pulmonary function values with serum ECP, no such relation was observed for sCD23. It appears that serum sCD23 and ECP concentrations could be good disease markers, particularly in asthma. Monitoring of serum inflammation markers, especially ECP, may be useful in the follow up of asthmatic children on anti-inflammatory treatment.

Evaluation of malignant and benign lung lesions with 99Tcm-tetrofosmin.

99Tcm-tetrofosmin planar imaging was performed in 30 patients with malignant and benign lung lesions. There were 21 cases of primary lung cancer (10 squamous cell, 5 small cell, 4 adenocarcinoma and 2 large cell) and 9 benign lung lesions (4 pneumonia, 3 tuberculosis, 1 infected bronchiectasis and 1 bronchiectasis obliterans). Anterior and posterior planar thorax images were obtained 30 min after the intravenous injection of 740 MBq (20 mCi) of 99Tcm-tetrofosmin. Visual and quantitative evaluations were performed. For the quantitative evaluation, regions of interest were drawn over the lesioned area (L) and over the contralateral non-lesioned area (N). Of 21 malignant primary lesions; 19 (90%) showed 99Tcm-tetrofosmin accumulation. Four (44%) of the nine benign lung lesions (3 cases of pneumonia and the one case of active tuberculosis) showed uptake. The mean L/N ratios for the malignant and benign lesions were 1.63 +/- 0.29 and 1.64 +/- 0.19, respectively. There were no significant differences (P > 0.05) in the L/N ratios of the malignant and benign lesions or the various histological types of cancer. In conclusion, 99Tcm-tetrofosmin was highly sensitive (90%) in detecting malignant lung lesions, but it had poor specificity (55%).

Serum levels of insulin-like growth factor-I and insulin-like growth factor binding protein-3 in children with insulin-dependent diabetes mellitus.

Pubertal development has recently been evaluated from the standpoint of changes in insulin-like growth factor (IGF)-I and IGF-binding protein-3 (IGFBP-3) levels in healthy children. We studied puberty related changes in serum IGF-I and IGFBP-3 levels in 24 patients (11 prepubertal) with insulin dependent diabetes mellitus (IDDM) and 26 healthy subjects (14 prepubertal). Serum IGF-I and IGFBP-3 levels were assayed using immunoradiometric assays and radioimmunoassays, respectively. Serum IGF-I and IGFBP-3 levels in diabetics did not increase during puberty, as opposed to those in healthy children. Serum IGF-I and IGFBP-3 levels of diabetic patients were found to be lower than those of control subjects during puberty (p < 0.0001 and p < 0.05, respectively). Proteolysis is believed to be a general mechanism to increase IGF bioavailability in the presence of IGFBPs. Increased IGFBP-3 protease activity has been shown in sera of children with IDDM as well as a decrease in this activity in response to insulin therapy. Our data displaying low IGFBP-3 levels in diabetic children may be due to increased proteolysis, which also causes a shift in IGF-I to its lower molecular weight forms. Higher rate of clearance of the latter may be the reason for the low IGF-I levels we observed in children with IDDM. The moderate correlation between insulin dose and IGFBP-3 levels (r = 0.5, p < 0.01) may suggest insulin to be a contributing factor in the regulation of IGFBP-3 levels. We conclude that regulation of IGF-I and IGFBP-3 concentrations is disturbed in children with IDDM, in particular during adolescence.

Effects of EGF and allopurinol on prostaglandin and lipid peroxide levels in mucosa of stomach in restraint cold stress.

The cold and restraint gastric stress models were used in rats. Mucosal levels of prostaglandins, which have a protective effect on cells, and lipid peroxidation, a possible etiological factor in stress-induced gastric mucosal injuries, were investigated. Epidermal growth factor (EGF), which protects the gastric tissue from stress-induced lesions, and allopurinol, which inhibits xanthine oxidase, were given intraperitoneally. Both EGF and allopurinol decreased lipid peroxidation at the mucosal surface of the stomach. At the same time, allopurinol increased the serum gastrin levels and decreased the mucosal prostaglandin levels. It is concluded that EGF protects the gastric mucosal surface by way of increased tissue prostaglandin levels. EGF also decreased both serum gastrin and tissue malondialdehyde, an indicator of lipid peroxidation.

Changes in serum type I and III procollagen levels in children with chronic renal failure.

Serum levels of carboxyterminal propeptide of type I procollagen (PICP) and aminoterminal propeptide of type III procollagen (PIIINP) can be used as markers of bone formation and the evaluation of children with growth disorders. We measured the serum levels of these collagens with radioimmunoassay in 24 children aged between 4 and 14 years with chronic renal failure (CRF; n = 12 dialysis, n = 12 nondialysis) and 12 age-matched healthy controls, to find out whether these parameters have a prognostic or therapeutic value in monitoring the growth retardation in CRF. Mean serum PIIINP levels in the dialysis patients were higher than in the control group; the difference between the groups was statistically significant (p < 0.05). It seemed that the pubertal stage of the patients did not affect the levels of PICP and PIIINP. There was no significant correlation between PICP and PIIINP in any patients. Neither PICP nor PIIINP correlated with the height z-score or bone age. It was concluded that the increased serum PIIINP levels in renal patients might be accepted as a poor prognostic factor leading to progressive renal failure and end-stage renal disease. Further investigations into the effects of these collagens on growth failure associated with CRF are needed.