Arecoline, but not haloperidol, induces changes in the permeability of the blood-brain barrier in the rat

The aim of the present study was to investigate the existence of alterations of the blood-brain barrier (BBB) permeability in rats injected with centrally acting drugs, by calculating a unidirectional blood-to-brain transfer constant (Ki) for the circulating tracer [14C]-alpha-aminoisobutyric acid. The intraperitoneal (i.p.) injection of the dopaminergic antagonist haloperidol (1 mg kg-1) did not modify the regional BBB permeability. When the cholinomimetic agent arecoline hydrobromide (6.25 mg kg-1) was injected i.p. into methylatropine-pretreated rats, it induced a significant decrease of Ki values within the frontal cortex, parietal cortex, striatum and brain-stem. Our findings emphasize two concepts: (1) centrally acting drugs, such as arecoline, can induce changes in the BBB permeability, through several mechanisms; (2) there is no predictable correlation of drug stimulation of specific brain neuronal pathways and changes in the permeability of the BBB.     

Partial vertical laryngectomies and reconstruction with plathysma myocutaneous flap

The authors report on 14 patients with epidermoid carcinoma of the glottic region, classified T1, T2 and T3, operated upon by a hemilaryngectomy (9 cases) with reconstruction using a Plathysma myocutaneous flap. The oncological results over a follow-up period of 1 to 6 years and the functional results are analyzed. The authors conclude that this method does not compromise the carcinological result and provides a good functional result with low ratings for complications, with in addition an adequate support for the organ, favouring increased resections.     

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.     

Pulmonary embolism.

Pulmonary embolism (PE) is an important health problem and often a major clinical challenge, not only because of the low specificity of its clinical manifestations but also because of the increasing number of medical circumstances that are risk factors for this illness and the importance of early identification, since prompt and appropriate treatment can decrease mortality from this disease by about 25%. In recent years research on PE has been extensive, directed mainly at trying to determine and characterize its risk factors, establish new clinical probability algorithms, develop new diagnostic methods and put existing ones into perspective, seek new therapeutic approaches (pharmacological and non-pharmacological), and above all establish protocols that can guide the clinician from the stage of clinical suspicion to measures to prevent recurrence. It was the authors' aim to review the most significant literature on this subject, in order to produce a text that reflects the state of the art concerning PE and that can be used as a guide in the clinical approach to this pathology.     

Absorption rates and free radical scavenging values of vitamin C-lipid metabolites in human lymphoblastic cells.

BACKGROUND: In this study we investigated the cellular absorption rates, antioxidant and free radical scavenging activity of vitamin C-lipid metabolites. The absorption was measured in a human lymphoblastic cell line using a spectrophotometric technique. MATERIAL/METHODS: Cellular vitamin C levels in the human lymphoblastic H9 cell line were measured using the 2,4-dinitrophenylhydrazine spectrophotometric technique. Free radical scavenging activity of vitamin C-lipid metabolites was measured by the reduction of 1,1-diphenyl-2-picryl hydrazyl (DPPH) to 1,1-diphenyl-2-picryl hydrazine. Vitamin C-lipid metabolite scavenging of peroxyl radical oxygen reactive species (ORAC) was determined by fluorescence spectrophotometry. RESULTS: Compared to ascorbic acid (AA), calcium ascorbate (CaA), and calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C), vitamin C-lipid metabolites (PureWay-C) were more rapidly absorbed by the H9 human T-lymphocytes. The vitamin C-lipid metabolites (PureWay-C) also reduced pesticide-induced T-lymphocyte aggregation by 84%, while calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C) reduced aggregation by only 34%. The vitamin C-lipid metabolites (PureWay-C) demonstrated free radical scavenging activity of nearly 100% reduction of DPPH at 20 microg/ml and oxygen radical scavenging of over 1200 micro Trolox equivalents per gram. CONCLUSIONS: These data demonstrate that the vitamin C-lipid metabolites (PureWay-C) are more rapidly taken-up and absorbed by cells than other forms of vitamin C, including Ester-C. This increased rate of absorption correlates with an increased protection of the T-lymphocytes from pesticide toxicities. Further, vitamin C-lipid metabolites (PureWay-C) are a potent antioxidant and have significant free radical scavenging capabilities.     

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.