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Epithelial Growth Factor receptors (EGFr) are normally present in all the epithelial cells, but their overexpression is closely related to presence of cancer. We have raised EGF-competitive antibody against EGFr and have labelled it with 131I and technetium. The ability of this antibody to bind to A431 cells to be internalized has been tested on A431 cells cultures. Its ability to give scintigraphic images of epithelial tumors has been tested on nu/nu balb c mice xenografted with A431 cells. The labelled antibody is well internalized by cultured cells. Xenografted tumors are clearly imaged both by 131I and 99mTc anti EGFr Mo/Ab. 99mTc labelling is very interesting. The tumor/background ratio was 0.72 +/- 0.2 for 99mTc and 0.40 +/- 0.6 for 131I labelling. Moreover very high uptake of 99mTc MoAb was obtained 2 hours after injection whereas the 131I antibody required 24 hours.

Subependymomas are rare, slow-growing, benign intraventricular tumors, which often are asymptomatic and are discovered incidentally. The review of the literature shows more than 100 symptomatic cases, less than half located in the lateral ventricles. Here we report 8 cases of symptomatic subependymomas of the lateral ventricles, studied by CT and/or MR and treated by direct surgical approach. The suspicion of a subependymoma should arise when a patient older than 10–15 years with long clinical history presents an intraventricular tumor isodense on CT and isointense in T1 and hyperintense in T2 on MR, with scarce or discrete contrast enhancement. Surgical treatment is indicated in symptomatic subependymomas of the lateral ventricles and usually allows complete tumor removal. The prognosis is usually good, also without postoperative irradiation.

We examined 14 patients, aged 10-25 years, with idiopathic hypopituitarism. All presented an ectopic posterior pituitary at the median eminence with a hypoplastic anterior pituitary on magnetic resonance imaging (MRI). Eight patients had isolated growth hormone deficit (IGHD) and six had multiple hormone deficits (MPHD). Unenhanced MRI showed the pituitary stalk, which was extremely thin, in only three patients, while T1-weighted images obtained after intravenous injection of gadopentetate dimeglumine (Gd-DTPA) showed a thin pituitary stalk in seven patients (six with IGHD and one with MPHD), demonstrating a preserved vascular component of the stalk. MRI with Gd-DTPA was more sensitive than unenhanced MRI in detecting the pituitary stalk in patients with hypopituitarism with an ectopic posterior pituitary: the stalk was demonstrated in 50 % of the cases (seven patients), versus 21.4 % (three patients) by unenhanced MRI. The dynamic study of the hypothalamo-hypophyseal axis performed with turbo-FLASH sequences after bolus injection of Gd-DTPA showed the residual anterior pituitary to have arterial enhancement times, which suggests that an arterial system compensates for the absent or diminished blood supply from the portal system, independent of stalk detection.

99mTc MIBI scintimammography is a sensitive and specific diagnostic technique for breast cancer detection when cancers more than 1 cm sized are considered. However the sensitivity falls in the case of submillimetric lesions. We developed a new Small Field of View, High Resolution Detector, able to image the breast in similar conditions of x-ray mammography: it allows the performance of Single Photon Emission Mammography (SPEM) studies. Seven patients with suspicion of malignant lesions were comparatively submitted to a Prone Scintimammography (PSM) by Anger camera and to a cranio-caudal view SPEM. The final diagnosis was reached by histopathology. Four malignant lesions were identified by SPEM but not by PSM, which that failed to image two submillimetric cancers. Both the cameras gave normal findings for benign lesions, confirming the high sensitivity of this technique. The results allow us to consider the SPEM camera as promising to improve scintimammographic sensitivity, even when small-sized tumors are examined.

Thirty-five patients with gastric cancer were preoperatively examined with CT performed in the prone position. Patient preparation consisted in filling the stomach with tap water and i.v. glucagon administration. The CT images were independently reviewed by two radiologists, who staged each tumor according to the TNM classification. The results were compared with surgical and histological findings. The overall accuracy for T staging ranged 74-77%, overstaging 17-23%; understaging was 3%. Diagnostic sensitivity, specificity and accuracy for serosal invasion were 100%, 80%, 85% and 100%, 84% e 88%, respectively, for the two radiologists. The overall accuracy for N staging was 48% and 51% for the two observers, respectively. Considering N1 and N2 as a single group, accuracy ranged 68-77%. The interobserver agreement analyzed by the "K tests" was 80%, with a K index of 60%. CT performed with the patient in the prone position, after preparation with gastric wall hypotony and distension with water, is a valid technique permitting excellent depiction of the gastric wall and providing useful preoperative information to the surgeon.

OBJECTIVE Magnetic resonance imaging (MRI) without contrast medium is unable to give detailed information on the hypothalamic-pituitary structures. MRI using gadopentetate dimeglumine (Gd-DTPA), and dynamic MRI, were performed in patients with hypopituitarism previously diagnosed as having anterior pituitary hypoplasia, ectopic posterior pituitary and unidentified pituitary stalk (1) to determine whether Gd-DTPA improves the delineation of hypothalamic-pituitary structures; (2) to verify whether, if so, such improvement can be correlated with residual pituitary function in patients subjected to long-term follow-up; and (3) to identify the hypothalamic-pituitary vascular network in such cases. PATIENTS Eighteen patients (13 males, 5 females) aged 10–26.4 years with unidentified pituitary stalk at first MRI study were evaluated. Eight had isolated GH deficiency (IGHD), and 10 had multiple pituitary hormone defect (MPHD) with the progression to complete anterior pituitary deficits seen by the age of 15 years in 8 patients (1 had GH and FSH–LH deficiency and 1 had GH, TSH and FSH–LH deficiency). RESULTS The MRI revealed a very thin pituitary stalk in 7 patients (38.8%), 6 with IGHD (75%) and 1 (10%) with MPHD (GH and FSH-LH deficiency), after Gd-DTPA administration. Reassessment of anterior pituitary function showed that the thyroid, adrenal and gonadal functions were intact in the 6 patients with IGHD and pituitary stalk identified by Gd-DTPA as well as in one IGHD patient with no evidence of pituitary stalk. In one 10-year-old with IGHD at the time of presentation (6 years) and no pituitary stalk seen after Gd-DTPA, subclinical hypothalamic hypothyroidism and suspected hypogonadotropic hypogonadism were documented. Partial ACTH deficiency was recorded In the patient with TSH and FSH–LH deficiency with no pituitary stalk. After Gd-DTPA, patients with absent pituitary stalk had a risk of developing MPHD 27 times greater than had those with an identified pituitary stalk (relative risk r=27, 95% confidence interval 1.9–368.4, Fisher’s exact test P=0.009). Dynamic MR images obtained every 4.6 s revealed rapid enhancement of hypothalamic-pituitary structures and allowed the determination of the times to initial enhancement of ectopic posterior pituitary and hypoplastic anterior pituitary which ranged between 9.2 and 18.4 s, and that of complete anterior pituitary (32.2–41.4 s). The time to maximum enhancement of anterior pituitary was significantly longer than in controls (35.5±3.8 s vs 25.2±1.6 s, P

Lack of dystrophin, a protein localized to the inner surface of the sarcolemma of the muscle fiber, is the cause of Duchenne type muscular dystrophy. Plasma membrane damage of the muscular fiber occurs, followed by Ca++ influx into the fibers. There is severe mitochondrial damage in dystrophic but still viable fibers. Five children aged 5-7 years were studied with MRI, TI-201, and Tc-99m sestamibi scintigraphy of the thighs. These three methods showed that the sartorius is the least damaged muscle in Duchenne type muscular dystrophy. MRI showed mild damage of adductors and quadriceps; TI-201 scintigraphy showed a marked reduction of radioactivity in the same muscles; Tc-99m sestamibi uptake occurred only in the sartorius muscle; the quadriceps was not imaged and adductors showed a faint image. A decrease of water in muscular fibers as well as fatty fibrous substitution, occurs after death of the fibers, whereas plasma membrane and mitochondrial damage reduced the uptake of tracers when the fiber is still viable. The interesting mismatch between sestamibi and TI-201 can be explained by considering that the cellular mechanism of uptake and retention of Tc-99m sestamibi involves both plasma membrane and mitochondria, whereas the uptake of TI-201 is only affected by plasma membrane damage.

A major gene for Hirschsprung's disease (HD) recently has been mapped in chromosome 10q11.2 and identified to be the RET proto-oncogene. Mutations of the RET gene have occurred in HD patients, and abnormalities of expression and function of Ret protein (a receptor tyrosine kinase, which is the product of the RET gene) have been found in their intestines. In vitro studies of the biological effects of HD mutations suggest a loss of function effect, which may be negative-dominant. However, the developmental role of the Ret protein in the organogenesis of the enteric nervous system (ENS) and its role in the pathogenesis of HD remain unclear. The authors present a study of the expression of Ret protein in the human ENS during fetal development. Fresh rectal tissues were obtained from nine fetuses (gestational age range, 12 to 22 weeks). Ret protein expression was studied immunohistochemically, using antibodies against the car☐y-terminal 20 amino acids (anti-Ret C) and the extracellular domain (anti-Ret R5). The tyrosine kinase activity of the fetal ENS was investigated with antiphosphotyrosine mouse monoclonal antibody against the phosphorylated tyrosine residues. Anti-Ret C immunostaining was observed in ganglion cells at all ages, but intense activity was significantly higher among the cells of the younger fetuses. Intense anti-Ret R5 immunostaining was present in the enteric ganglion cells of the 12-week-old fetus. The tyrosine kinase activity of ganglion cells increases progressively with advancing gestational age. The results of this study support the hypothesis that the Ret protein receptor might play a crucial role in the cellular and molecular processes involved in the development and maturation of the ENS, abnormalities of which could result in HD. High Ret protein expression and low tyrosine kinase activity have been reported to occur in small ganglia of the HD hypoganglionic segment. In the present study, these markers were typical of the primitive and immature ENS during the early phase of hindgut development.

Since somatic mutations are suspected to contribute to the pathogenesis not only of cancer but also of atherosclerotic plaques, we measured DNA adducts in the smooth muscle layer of atherosclerotic lesions in abdominal aorta specimens taken at surgery from seven patients. DNA adducts were evaluated in three laboratories by means of different molecular dosimetry methods, including: (a) HPLC/fluorescence, which specifically identifies the DNA adducts of the anti-benzo(a)pyrene (BPDE) isomer; (b) two- and three-dimensional synchronous fluorescence spectrophotometries, which detect DNA adducts of BPDE and other reactive metabolites of polycyclic aromatic hydrocarbons; and (c) 32P postlabeling, which reveals the presence of a variety of types of DNA adducts. The HPLC/fluorescence method provided for the first time evidence for the presence of BPDE-DNA specific adducts in three of six specimens tested. Synchronous fluorescence spectrophotometry displayed broad areas of fluorescence in all seven specimens, thereby suggesting the occurrence not only of BDPE-DNA but also of other DNA adducts with similar fluorescence characteristics. All specimens were also positive at 32P postlabeling, which revealed multiple spots detectable following enrichment either with nuclease P1 or butanol, indicative of the presence of different aromatic DNA adducts. Thus, the data obtained by applying typical cancer biomarkers provide further support to the hypothesis that there may be similarities between the carcinogenic and the atherogenic processes, and in particular that genetic alterations caused by DNA-binding agents in the artery wall may be detected in atherosclerotic lesions.

Objective To investigate whether endogenous dopaminergic activity is impaired in polycystic ovary syndrome (PCOS)-affected women and is normalized by medical ovariectomy. Patients Women with PCOS untreated (n = 23) and treated for 3 months with GnRH analogue (GnRH-a) administration (n = 10) and normal cycling young women (n = 23) as controls. Interventions Acute blockade of dopaminergic receptors by the IV administration of 5mg of the dopaminergic receptor blocking agent sulpiride (sulpiride test) was performed 3 to 7 days after the initiation of spontaneous menses in cycling women or medroxyprogesterone acetate-induced menses in PCOS women. In PCOS women treated with GnRH-a administration (goserelin depot, 3.6mg SC every 28 days), the sulpiride test was repeated 10 to 15 days after the third GnRH-a administration. Main Outcome Measure Basal PRL levels and PRL increase induced by sulpiride. Results Basal PRL levels and the PRL response to sulpiride were increased in women with PCOS. In women with PCOS medical ovariectomy induced by GnRH-a administration reversed to normal both basal and sulpiride-stimulated PRL levels. Conclusions In women with PCOS the abnormal regulation of PRL and presumably of hypothalamic neurotransmitters controlling PRL secretion is not a primary alteration but it is likely dependent on abnormal ovarian functionality.

[123I]MIBG has been proposed as a suitable tracer of the adrenergic system of the heart. The aims of this study was to investigate the adrenergic functional status of the heart in hypertensive patients with left ventricular hypertrophy (LVH), and to evaluate the distribution of neuroadrenergic terminals in patients with left ventricular aneurysms (LVA) presenting complex arrhythmias. We studied 21 patients (4 normals, 11 with LVH and hypertension, and 6 with previous myocardial infarction, LVA and complex arrhythmias) who underwent series of [123I]MIBG planar scans (from 0.5 to 24 hours p.i.) and SPECT scans using both [123I]MIBG and 201Tl. Data quantification was performed by calculating the heart/mediastinum ratio (planar scan) and the percent uptake in 5 myocardial regions (SPECT scan). No significant differences between normals and hypertensive patients were found either in the heart/mediastinum ratio or in the regional distribution of [123I]MIBG and 201Tl. In hypertensive patients the uptake of [123I]MIBG was significantly higher than that of 201Tl in the septal wall while in the lateral and inferior walls it was significantly lower. In patients with anteroapical myocardial infarction (MI), the size of the [123I]MIBG defect was slightly smaller than the 201Tl defect; moreover a constant, severe [123I]MIBG defect was observed in the inferior walls whereas 201Tl uptake was normal. We conclude that while in hypertensive patients adrenergic innervation seems to be slightly impaired as compared to myocardial perfusion, in patients with MI a large area of functional or anatomical denervation may be detected despite the preserved perfusion and viability; this mismatch may be the trigger of complex arrhythmias.

Whether the biological effect of melatonin in humans is directly related to the circulating levels of the hormone, has not heretofore been investigated. In this study, we investigated whether previously described hypothermic melatonin properties are dose related. The nocturnal decline of the body temperature (BT) observed in 16 early follicular phase women, following placebo administration at 18.00 h, was compared with that observed during the preceding or following night, after melatonin suppression with the beta 1-adrenergic antagonist atenolol (100 mg). In 6 subjects (37.5%) with lower nocturnal melatonin levels (p0.05) atenolol induced a complete melatonin suppression and an attenuation of the nocturnal BT decline (p0.02), whereas in the remaining 10 subjects (62.5%) atenolol induced an incomplete melatonin suppression with no modification of the nocturnal BT decline. During a 3rd night, 2 of the 6 subjects with complete and 6 of the 10 subjects with incomplete melatonin suppression blindly received atenolol plus melatonin (1 mg at 19.30 h and 0.75 mg at 21.00 and 23.00 h). Exogenous melatonin restored the full expression of the nocturnal BT decline in the 2 subjects with complete melatonin suppression, but did not modify the BT decline in the 6 subjects with atenolol-induced incomplete melatonin suppression. Our data show that markedly, but not completely attenuated nocturnal melatonin levels are sufficient to exert maximal thermoregulatory effects, indicating rather a threshold than a dose-response effect of melatonin action on human BT.

This paper reports on an original method to prepare a contrast agent consisting of CO2 microbubbles to be injected i.a. during ultrasound examinations (ultrasound angiography-USA), whose value was investigated in the study of tumor neovascularity in HCC patients. Thirty-five HCC patients underwent USA. CO2 was drawn out from a gas container under pressure and, through a sublimation process, made available in predetermined quantities in test tubes. USA was performed during angiography in 9 cases and immediately before arterial chemoembolization in the other 26 cases. In 51 lesions vascularity was evaluated with conventional angiography, USA and lipiodol CT. USA demonstrated lesion hypervascularity in 91% of cases, as confirmed by lipiodol CT (88%), versus 72.4% of angiography. In 3 of 35 patients USA demonstrated 6 more lesions undetected by other modalities: two of them were proved to be HCC and adenomatous hyperplasia at percutaneous biopsy. USA is a cost-effective procedure, which is easy to perform during conventional angiography: it is more sensitive than conventional angiography in the study of lesion neovascularity and can help plan lesion management, anticipating the results of chemoembolization. The role of USA in the diagnosis and treatment of HCC is, however, still to be defined.

To evaluate the relationship between stressful life events and the onset of secondary amenorrhoea Paykel's semi-structured interview for Recent Life Events was administered to patients affected by secondary amenorrhea and also to healthy volunteers. The number, quality, and objective negative impact of life events were compared among different hormonal subtypes of secondary amenorrhoea and healthy normally menstruating women, as a control group. The number of life events in amenorrhoeic patients (N=131) was significantly greater than those observed in the control group (N=64) (45.9 vs 32.8%). Moreover, where only hypothalamic hypogonadotrophic amenorrhoea was considered, the occurrence of life events was significantly higher (59.8%) than in hyperandrogenic (26.6%) or in normogonadotrophic (20.4%) patients. The most prevalent events among hypothalamic hypogonadotrophic amenorrhoeic patients were those classified as ‘undesirable’, ‘uncontrolled’ and with ‘Objective Negative Impact’. The present study supports the hypothesis of a cause-effect relationship between stressful personal life events and the onset of secondary amenorrhoea of hypogonadotrophic subtype.

This study examined brain areas involved in tonic pain perception. Cerebral blood flow was assessed by dynamic Xenon-133 inhalation single-photon emission tomography (SPET) in 7 healthy right-handed male volunteers undergoing the cold pressor test (CPT). In single experimental sessions, each subject was scanned twice, once in the resting state and once while immersing the left hand in freezing water (0° C ± 1). Immersion of the hand induced severe pain (visual analogue scale: 6.9 ± 1.9) in all subjects. After correction for pCO 2 , cerebral blood flow was analyzed by placing a template of square regions of interest (ROIs) over 5 selected tomographic slices. Relative to the resting-state values, during the CPT, flow determinations revealed a 7–8% regional blood flow increase in the contralateral frontal lobe and bilateral temporal regions and a 15% flow increase in a ROI located over the primary sensorimotor cortex in the tomogram at 80 mm above the orbito-meatal line (corresponding to the cortical somatotopic representation of the hand) contralateral to the stimulated side. The tonic pain induced by the CPT thus appears to activate the contralateral frontal and bilateral temporal regions and more prominently, the primary sensorimotor cortex. This pattern of activation suggests that tonic painful stimuli activate the cortex partly via complex circuits and partly via direct somatosensory pathways.

In gastric cancer patients, CT can demonstrate wall lesions, tumor spread to adjacent organs and metastases. Since the disease is often diagnosed in an advanced stage, some authors used CT to stage the tumor and to avoid surgery in the patients with unresectable lesions. We compared CT staging results with surgical findings in 22 gastric cancer patients. After fluid-filling and hypotonization of the stomach, CT detected gastric wall thickening in all cases. In 4 patients neoplastic nodes1 cm were considered as normal on CT images, while in 2 patients some nodes1.5 cm which had been considered as metastatic were negative at histology. Overall CT accuracy in diagnosing nodal involvement was 73%. The lack of fat plane used as the evidence of direct invasion of adjacent organs exhibited 45% overall accuracy for hepatic involvement and 82% accuracy for pancreatic involvement. Seven cases (32%) were mis-staged by CT: 4 patients (18%) were under-staged and 3 (14%) were over-staged. Since it does not always show the real extent of the disease, in the staging of gastric cancer CT is to be considered a complementary tool to surgical staging, even though it is often necessary to choose between radical or palliation surgery.

To assess pituitary vascularization in children with hypopituitarism, central diabetes insipidus (DI), or Langerhans cell histiocytosis.Dynamic MR images were obtained through the pituitary stalk after injection of gadopentetate dimeglumine in 21 patients (11 boys and 10 girls, aged 4-17 years) and 10 age-matched control subjects.Initial enhancement of the posterior pituitary lobe occurred simultaneously with that of the straight sinus in all subjects except four patients with central DI and a thick stalk. Enhancement of the entire anterior pituitary lobe was statistically significantly prolonged (P.005) in the four patients with delayed initial posterior pituitary lobe enhancement.Fast-framing dynamic MR imaging provides new information on the blood supply of the hypothalamic pituitary area in normal and abnormal pituitary glands. Enhancement times exceeding 20 seconds for the posterior pituitary lobe and 30 seconds for the anterior pituitary lobe may suggest abnormal vascularization in the hypophyseal arteries and portal system.

Single photon emission tomography (SPET) with the novel ligand [123I]-IBZM was used to image central dopamine D2 receptors in Parkinson's disease (PD) patients. The aim was to assess basal ganglia (BG) receptor densities in relation to the response to L-dopa therapy. To better characterize the clinical potential of [123I]-IBZM SPET, each patient underwent a second study with the regional perfusion tracer [99mTc]-HM-PAO. Tracer activity ratios were calculated for caudate and putamen with mean activity over the cerebellar hemispheres as internal standard. In PD patients we found a significant decline of mean caudate [123I]-IBZM activity, as compared with age-matched control subjects. However, when patients were grouped according to their therapeutic behavior, the [123I]-IBZM uptake in BG ganglia regions of the PD patient group with a poor and fluctuating response to L-dopa was significantly reduced from mean values of patients with a sustained response to L-dopa therapy. [99mTc]-HM-PAO caudate and putamen uptake indexes in PD were similar to control values, even in patients with deteriorated therapeutic response. Our results indicate that BG D2 receptor alterations in PD may contribute to the altered response to L-dopa.

The authors evaluated the degree of fatty infiltration of the liver in subjects with diffuse liver steatosis using image-guided 1H localized MR spectroscopy and correlated the magnetic resonance (MR)-determined fat fraction with the computed tomography (CT) liver/spleen density ratio and histologic evaluation.MR measurements were performed at 1.5 T by applying a double-spin-echo localization sequence. Twenty-six patients underwent MR and CT examinations and ultrasound (US)-guided biopsy. Additionally, three healthy volunteers underwent MR examination. Steatosis severity was estimated using 1) the ratio between fat and total MR signal areas; 2) the ratio between liver and spleen CT number; and 3) histologic score.The linear correlation between MR fat/fat-plus-water signal ratio and CT liver/spleen density values ratio is statistically significant. Both techniques correlate well with histologic score. No significant correlation exists between water or fat T2 values and the severity of steatosis.1H MR spectroscopy allows a noninvasive estimate of the hepatic fat content.

If we define erectile impotence as the inability to achieve and maintain a firm erection we can distinguish several pathogens of impotence: psychologic disorders, neurogenic sinusoidal disorders, arterial disorders, venous & sinusoidal disorders and systemic diseases and other disorders can cause erectile impotence. An etiologic screening of impotence must be carried out by Urologists in order to adopt the best surgical approach. Especially when surgery has to be planned, a complete, often invasive screening associated with a super-specialist diagnostic study is necessary at the beginning of any procedure. Different approaches to impotence can be adopted on the basis of patient's age, etiology and failure of other devices. The main methods of surgical correction of impotence may be divided as follows: a) percutaneous transluminal angioplasty (P.T.A.); b) revascularization; c) surgical treatment of "venous leakage", d) trans-luminal veno-occlusion (T.L.V.O.); e) correction of penile curvature; f) prostheses placement. The diagnosis of arteriogenic impotence depends upon the arteriographic demonstration of bilateral hemodynamically significant obstruction. In our experience the injection of papaverine during the test has provided a better visualization of cavernous arteries and helicine branches. Reduction of luminal diameter by more than 50\% suggest a hemodynamically significant stenosis. Intracavernous injection of vasoactive agents has provided an attractive alternative to surgery. We have employed papaverine alone or with phentolamine or phenoxybenzamine. After short term treatment, some patients have achieved good erections without further injections. For P.T.A. of the distal internal pudendal arteries our approach has been via the ipsilateral or contralateral femoral arteries. Under local anesthesia a penile arteriographic catheter is placed in the internal pudendal artery.(ABSTRACT TRUNCATED AT 250 WORDS)

PURPOSE: To describe the MR findings in the hypothalamic pituitary area in children with Langerhans cell histiocytosis and to define those MR alterations especially associated with the risk of developing diabetes insipidus. METHODS: The hypothalamic-neurohypophyseal axis was studied by sagittal and coronal 1.5 T1-weighted MR imaging in 14 children with Langerhans cell histiocytosis (five with diabetes insipidus) and in 28 low-stature controls, ages 6-14 years. RESULTS: The pituitary stalk was thicker in seven/14 patients (three with diabetes insipidus) than in controls (P less than .05). Bright posterior pituitary signal was undetectable in children with diabetes insipidus and in one/9 without diabetes insipidus. CONCLUSIONS: Thickening of the hypothalamus and/or the pituitary stalk in the absence of the posterior pituitary bright signal is seen in children with Langerhans cell histiocytosis with overt diabetes insipidus. Those Langerhans cell histiocytosis patients without diabetes insipidus but showing thickened stalk with or without posterior pituitary bright signal could be at high risk to develop diabetes insipidus.

Twenty patients with hemiplegia and 13 patients with motor neurone disease were studied with electrical and magnetic transcranial stimulation. Motor evoked potentials were recorded from the biceps, thenar and tibialis anterior muscles. In both groups of patients magnetic stimulation with a Novametrix stimulator revealed fewer abnormalities than electrical stimulation with a Digitimer D180 stimulator. In patients with hemiplegia, motor evoked potentials after electrical stimulation were absent in 70% of muscles, delayed in 22% and normal in 8%; after magnetic stimulation, they were absent in 53% of muscles, delayed in 28% and normal in 19%. In patients with motor neurone disease, motor evoked potentials after electrical stimulation were absent in 62% of muscles, delayed in 10%, and normal in 29%; after magnetic stimulation, they were absent in 45% of muscles, delayed in 15%, and normal in 40%. The reason why magnetic stimulation reveals fewer abnormalities than electrical stimulation could be that magnetic stimulation repetitively discharges the pyramidal cells and, because of temporal summation mechanisms, produces more powerful excitatory potentials at the lower motoneurone synapse.

Predictive values of ST HR slope and ST-segment displacement during symptom-limited exercise were determined in 85 patients who underwent coronary angiography for suspected coronary artery disease, using perfusional and functional radionuclide images with 99mTc-2-methoxy-isobutil-isonitrile as an index of stress-induced myocardial ischemia. ST HR slope showed a better sensitivity than conventional stress-induced changes of ST-segment displacement (96% vs. 73%, respectively). In patients with clinical suspicion of coronary artery disease, the main result was the negative predictive value of ST HR slope when compared with conventional St-segment displacement (98% vs. 41%). ST HR slope was unable to perfectly separate patients with different degrees of ischemia, however, subjects without scintigraphic signs of stress-induced ischemia and patients with ischemic impairment in three myocardial regions were correctly identified as distinct populations. In patients with a previous myocardial infarction, no difference was found between the two criteria and a wide overlap of ST HR slope values was present. The authors conclude that ST HR slope is useful to detect the rate of change in electric parameters during exercise and might therefore more adequately be used to separate normal from definitely abnormal responses to exercise.

The lectin histochemistry of ameloblastoma was investigated in order to understand the nature of the carbohydrate residues in this tumor, in accordance with the WHO subclassification. Mannose and glucose were generally common in almost all cells in both the follicular and plexiform types, especially stellate cells and cystic lesions of the follicular type. N- acetylglucosamine (GlcNac), N-acetylneuraminic acid (NANA) and galactose were much more abundant in stellate cells of the plexiform type than in those of the follicular type. Thus, there is a slight difference in lectin histochemistry of the stellate cells between the follicular and plexiform types of ameloblastoma.

Lectins are sugar binding proteins or glycoproteins of non-immune origin derived from various plants or animals with specific sugar binding capacity. This property of lectins can be used to identify structural differences between normal and malignant cells. Malignant transformation is accompanied by several changes in cell membrane. Studies have shown that the lectin binding pattern of these cells may indicate the invasive potential of tumours. Lectins can also be used as carriers. Lectins conjugated to chemotherapeutic agents has been found to be more useful in the treatment of tumours induced in animals.

Beta-endorphin (beta-Ep) plasma levels are higher in obese patients than in normal subjects. To establish that this finding constitutes hyperendorphinemia, 28 obese patients aged 12-55 years, six males and 22 females, (weighing 61-117 kg) were investigated twice by an overnight 1-mg p.o. dose dexamethasone suppression test (DST) before and after weight loss. beta-Ep was measured by radioimmunoassay (RIA). Before body weight loss, beta-Ep was higher than normal and unresponsive to DST, whereas ACTH and cortisol were suppressible. After weight loss, beta-Ep was slightly reduced but still insensitive to DST. ACTH and cortisol were responsive as usual. Findings suggest a resistance to DST in obesity as far as beta-Ep is concerned. The disorder persists even after weight loss, indicating that hyperendorphinemia is not secondary to body weight excess. Accordingly, one can argue that the unresponsiveness of the endorphinergic system to its physiological feedback is a pathophysiological characteristic of obesity.

We studied the Schwann cell (SC) GFAP immunoreactivity in normal human peripheral nerves and in neuropathies of different origin. Immunofluorescence and immunocytochemistry were carried out on serial frozen sections of 58 peripheral nerve biopsies using monoclonal antibodies (mabs) antivimentin and anti GFAP, and antiserum anti S-100 and anti GFAP. To test the specificity of the mabs and antiserum used, proper competition controls on tissue sections of 2 selected cases, tissue cultures studies of human fibroblasts and immunoblotting of homogenates of human fibroblasts, 3 normal and 5 pathologic nerves were carried out. In order to evaluate a possible correlation between SC GFAP positivity and neuropathologic findings a quantitative study was performed, evaluating the SC GFAP reactivity in all the 58 cases, and relating the SC GFAP positivity to the index of nerve pathology (IP) in 9 selected cases, and to the percentage of teased fibers showing axonal degeneration or demyelination and remyelination in 25 representative cases. We demonstrate that in normal human sural nerves and in demyelinating neuropathies only a few scattered SC are recognized by the mabs or antiserum anti GFAP. On the contrary in axonal neuropathies the majority of SC gain the property to express intermediate filaments which show common antigenic properties with GFAP.

Thirty-four demented patients, 19 with Alzheimer's and 15 with multi-infarct dementia, were studied using single photon emission computed tomography, and 99mTc-hexamethyl-propylenemine oxime as a tracer of regional cerebral perfusion. Tracer activity ratios, determined in cortical and subcortical regions, were compared with those of 11 age-matched controls. In both groups of demented patients, most of the cortical regions showed significant declines in tracer uptake from control values, with the greatest reductions in the parietal cortex. Significantly lower parietal indexes were found in the Alzheimer's patient group as compared both to the control values and to the group of multi-infarct dementia patients. A positive correlation was found between the magnitude of the parietal deficits and the severity of dementia.

Inositol hexakisphosphate (InsP6) is thought to act as an intercellular signal molecule in the central nervous system. We report that InsP6 stimulates 45Ca2+ uptake in cultured anterior pituitary cells. This effect is concentration-dependent is mimicked by inositolpentakis phosphate (InsP5) but not by inositoltetrakis phosphate (InsP4), is present after 2 min of incubation, is independent of extracellular Na+ and insensitive to nifedipine and verapamil. These results suggest that InsP6, a putative metabolite of the inositol cycle, may regulate transmembrane mechanism in the pituitary.

Congenital tracheo-esophageal fistula without esophageal atresia was diagnosed on barium swallow radiography and esophagoscopy findings in an adult patient presenting with difficult in swallowing. The fistulous opening seen on the anterior wall of the esophagus led to the trachea. On bronchoscopy, the tracheal opening was located posteriorly 5 cm below the vocal cords. Successful repair was undertaken via a left cervical approach. The anatomical and developmental basis for the preferred approach is discussed with a brief literature review on the subject.