rCBF abnormalities detected,and sequentially followed,by SPECT in neuro-Behcet's syndrome with normal CT and MRI imaging

Summary Conventional imaging with computed tomography (CT) and magnetic resonance imaging (MRI) may show abnormalities in central nervous system Behcet's syndrome but is normal in some cases. Recently in two cases positron emission tomography has shown abnormalities in blood flow and glucose metabolism far more extensive than the abnormalities seen on CT and MRI scans in the same patients. We report a patient with neuro-Behcet's syndrome presenting with headache and personality change in whom CT and MRI brain imaging was normal, but regional cerebral blood flow imaging using single photon emission tomography with the tracer HMPAO showed extensive perfusion deficits which partially reversed after 3 months of prednisolone therapy. This technique may aid the diagnosis of cerebral involvement in Behcet's syndrome, although the cause and incidence of the perfusion deficits need further evaluation.     

Initial evaluation of123|-5-|-R91150, a selective 5-HT2A ligand for single-photon emission tomography, in healthy human subjects

The mapping of 5-HT₂ receptors in the brain using functional imaging techniques has been limited by a relative lack of selective radioligands. Iodine-123 labelled 4-amino-N-[1-[3-(4-fluorophenoxy)propyl]-4-methyl-4-piperidinyl]-5-iodo-2-methoxybenzamide (¹²³I-5-I-R91150 or¹²³I-R93274) is a new ligand for single-photon emission tomography (SPET), with high affinity and selectivity for 5-HT_2A receptors. This study reports on preliminary¹²³I-5-I-R91150 SPET, wholebody and blood distribution findings in five healthy human volunteers. Maximal brain uptake was approximately 2% of total body counts at 180 min post injection (p.i.). Dynamic SPET sequences were acquired with the brain-dedicated, single-slice multi-detector system SEM-810 over 200 min p.i. Early peak uptake (at 5 min p.i.) was seen in the cerebellum, a region free from 5HT_2A receptors. In contrast, radioligand binding in the frontal cortex increased steadily over time, up to a peak at approximately 100–120 min p.i. Frontal cortex-cerebellum activity ratios reached values of 1.4, and remained stable from approximately 100 min p.i. onwards. Multi-slice SPET sequences showed a pattern of regional variation of binding compatible with the autoradiographic data on the distribution of 5-HT_2A receptors in (cerebral cortex>striatum>cerebellum). These findings suggest that¹²³I-5-I-R91150 may be used for the imaging of 5-HT_2A receptors in the living human brain with SPET.     

Giant splenic metastasis due to lung adenocarcinoma

Lung cancer is the most prevalent malignancy in western countries and most of the patients present at advanced stages, but single splenic metastasis is exceptional instead. We report on a case of a seventy-three-year old male presenting with non-hemoptoic productive cough, constitutional syndrome and pain in the left lower quadrant. Physical examination and complementary radiological and hystologycal procedures revealed the presence of an adenocarcinoma of the left lung with probable splenic metastasis. The patient underwent splenectomy, which confirmed the diagnose of splenic metastasis of lung adenocarcinoma and, secondly, lung resection was performed. Topics about lung cancer metastasis are discussed.     

Cadralazine and chlorthalidone as a second-step drug with atenolol in hypertensive patients: Differences in blood pressure control during exercise

Summary The long-term efficacy of a new vasodilator, cadralazine (ISF 2469), and chlorthalidone have been compared in 20 hypertensive patients not adequately controlled by atenolol. After 4 weeks of treatment with atenolol 100 mg once daily, patients whose diastolic blood pressure was >95 mmHg were randomly divided into two groups to receive in addition to atenolol, either cadralazine 15 mg once daily or chlorthalidone 25 mg once daily. Both treatments were administered for 6 months. At the end of treatment with atenolol and after 3 and 6 months of combination therapy, blood pressure and heart rate were measured at rest and during bicycle exercise 24 h after the last dose. Compared to atenolol alone, both cadralazine and chlorthalidone caused a significant and similar reduction in resting blood pressure. Both groups showed an increase in diastolic blood pressure during exercise while receiving atenolol alone. The addition of chlorthalidone did not modify the pressor response to exercise, whereas patients taking cadralazine had a decrease in exercise diastolic blood pressure, which was fully evident after 6 months of therapy. The reduction in exercise diastolic blood pressure induced by cadralazine was proportional to the increase in exercise heart rate, suggesting a fall in peripheral vascular resistance. Chlorthalidone caused a significant increase in serum glucose and uric acid and a decrease in K⁺, whereas no change was observed during cadralazine It is concluded that cadralazine given once a day with atenolol has the same efficacy in controlling blood pressure at rest as the combination of atenolol and chlorthalidone, and in addition it improves the pressor response to dynamic exercise and does not cause unwanted metabolic effects.     

Method of measuring deposition of unlabeled monodisperse microspheres in rat lungs

A system to simultaneously measure the total deposition of four different sizes of monodisperse microspheres in normal and damaged lungs of rats was developed and tested. The system reproducibly measured the deposition of microspheres in control rats, and the procedure was shown to be sufficiently sensitive to measure ozone-induced changes in deposition rates. Rats exposed to 1.2 ppm ozone 6 h/d for 2 consecutive days showed greater deposition of the 1.09-micron-, 2.02-micron-, and 2.99-micron- but not of the 0.48-micron-diameter microspheres when compared to controls. After 8 consecutive days of exposure to the same concentration of ozone, there were no differences in deposition rates between control and ozone-exposed rats. Respiratory physiology and lung histopathology data provided evidence that subtle changes in the airway architecture and/or aerodynamics were likely to be responsible for the differential deposition rates as a function of the duration of ozone exposure.     

Age, personality, and the Holtzman Inkblot Technique

Recent longitudinal studies using personality questionnaires and ratings have shown remarkable stability across the adult years. In an investigation of age changes and differences in personality as measured by the Holtzman Inkblot Technique (HIT), ninety-three men and women aged twenty-five to ninety were administered Form A of the HIT; forty-four of these were retested one to three years later. Stability coefficients ranged from .07 for Form Appropriateness to .73 for Form Definiteness, with most variables showing significant but moderate stability. Repeated measures analyses of variance showed increases in six variables and decreases in two others, but only one of these changes was paralleled by cross-sectional age differences. Correlations with self-report measures of the broad personality domains of neuroticism, extraversion, and openness to experience failed to show hypothesized relations, and the associations seen were attributable to chance. It was concluded that the HIT measures perceptual-cognitive variables that are moderately stable in adulthood.     

Interaction of short chain aliphatic alcohols with muscarinic receptor-stimulated phosphoinositide metabolism in cerebral cortex from neonatal and adult rats.

Muscarinic receptor-stimulated phosphoinositide metabolism has been recently suggested as a possible target for the neurotoxic effects of ethanol during brain development. Since two other alcohols, tertiary butanol and n-propanol, have been shown to cause microencephaly in the rat when administered during the brain growth spurt, in the present study we investigated the in vitro effects of five short chain aliphatic alcohols on muscarinic receptor-stimulated phosphoinositide metabolism in cerebral cortical slices from 7 day-old rats. In neonatal animals all alcohols tested inhibited carbachol (1 mM)-stimulated [3H]inositol phosphates accumulation in a dose- and time-dependent manner. The order of potency was t-butanol greater than n-propanol greater than or equal to iso-propanol greater than ethanol greater than methanol. After 90 min of incubation, ethanol, n-propanol and t-butanol caused a significant inhibition of muscarinic receptor-stimulated inositol metabolism at doses as low as 15 - 50 mM, comparable to the blood concentrations reached after in vivo administration of doses able to induce developmental neurotoxicity. The inhibitory effect of ethanol was additive to that of iso-propanol or t-butanol. Differently from these effects in 7 day-old rats, in cortical slices from adult animals methanol and ethanol had no effect on carbachol-stimulated phosphoinositide metabolism, while the two propanol isomers and t-butanol were less effective than in neonatal animals. These results suggest that muscarinic receptor-coupled phosphoinositide metabolism might be a common neurochemical target for the developmental neurotoxicity of short chain aliphatic alcohols.