[New rules on hypolipidemic drug reimbursability in Italy]

The Italian National Committee for Drugs (CUF) has recently reviewed the reimbursement criteria for hypolipidemic drugs in our country. The new rules allow the reimbursement of statins and fibrates in patients with familial dyslipidemias, and of statins in hypercholesterolemic subjects who are not responders to an appropriate diet and are at high risk of a first major cardiovascular event, or already affected by coronary heart disease. To evaluate the level of coronary risk, the new document suggests to use risk algorithms or risk charts. The use of the risk charts recently published by the European Societies of Cardiology, Hypertension and of Atherosclerosis, and based on the Framingham algorithm, is suggested for risk grading of patients without clinically overt coronary heart disease. For coronary patients, the risk chart based on the follow-up of the cohort of the Italian GISSI-Prevenzione study should be used. Therefore, the reimbursement of statins will no longer be linked, according to this document, to cholesterol plasma levels, but rather to a specific level of coronary risk. By following these guidelines, the theoretical ground for a more appropriate use of these drugs, also characterized by a more favorable cost-benefit ratio, is established. Even if some aspects of the CUF document may need revision or clarification, it can be envisaged that it will favorably impact on the quality of cardiovascular prevention in our country.

The calcium-dependent [3H]acetylcholine release from synaptosomes of brown trout (Salmo trutta) optic tectum is inhibited by adenosine A1 receptors: effects of enucleation on A1 receptor density and cholinergic markers

Presynaptic inhibition is one of the major control mechanisms in the CNS. Previously we reported that A1 adenosine receptors are highly concentrated in the brain, including optic tectum, of trout and that they inhibited the release of glutamate. The optic tectum is heavily innervated by cholinergic nerve terminals. We have investigated whether A1 receptors inhibit the presynaptic release of acetylcholine and whether the inhibition is triggered by calcium. The release of [3H]ACh evoked by 30 mM KCl was Ca2+ dependent and it was dose-dependently inhibited by the A1 adenosine receptor agonist 2-chloro-N(6)-cyclopentyladenosine (CCPA) ranging between 10 nM to 100 microM. The maximum of inhibition was reached at 10 microM. The A1 receptor antagonist 8-cyclopentyltheopylline (CPT, 10 microM), reversed almost completely the inhibition induced by CCPA 10 microM. In Fura-2/AM loaded synaptosomes, K(+) depolarization raised [Ca2+](i) by about 64%. CCPA (10 microM) reduced the K(+)-evoked Ca2+ influx increase by about 48% and this effect was completely antagonised by CPT 10 microM. Synaptosome pretreatment with different Ca2+ channel blockers differently affected K(+)-evoked Ca2+ influx. This was not significantly modified by nifedipine (1 microM, L-type blocker) nor by omega-agatoxin IVA (0.3 microM, P/Q-type blocker), whereas about 50% reduction was shown by 0.5 microMomega-conotoxin GVIA (N-type blocker). Neurochemical parameters associated with cholinergic transmission and the density of A(1) adenosine receptors were measured in the trout optic tectum 12 days after unilateral eye ablation. A significant drop of both acetylcholinesterase (AChE) activity (24%) and choline acetyltransferase (CAT) activity (32%) was observed in deafferentated optic tectum, whereas the high affinity choline uptake did not parallel the decrease in enzyme activity. Eye ablation caused a marked decrease (43%) of A1 receptor density without changing the affinity. The K(+)-evoked release of [3H]ACh from synaptosomes of deafferentated was not modify as well as the efficacy of 10 microMCCPA in decreasing [3H]ACh release was not apparently modified.

Immunogenicity of an anti-clade B feline immunodeficiency fixed-cell virus vaccine in field cats

Attempts at vaccine development for feline immunodeficiency virus (FIV) have been extensive, both because this is a significant health problem for cats and because FIV may be a useful vaccine model for human immunodeficiency virus. To date, only modest success, producing only short-term protection, has been achieved for vaccine trials in controlled laboratory settings. It is unclear how relevant such experiments are to prevention of natural infection. The current study used a vaccine that employs cell-associated FIV-M2 strain fixed with paraformaldehyde. Subject cats were in a private shelter where FIV was endemic, a prevalence of 29 to 58% over an 8-year observation period. Cats roamed freely from the shelter through the surrounding countryside but returned for food and shelter. After ensuring that cats were FIV negative, they were immunized using six doses of vaccine over a 16-month period and observed for 28 months after the initiation of immunization. Twenty-six cats (12 immunized and 14 nonimmunized controls) were monitored for a minimum of 22 months. Immunized cats did not experience significant adverse effects from immunization and developed both antibodies and cellular immunity to FIV, although individual responses varied greatly. At the conclusion of the study, 0 of 12 immunized cats had evidence of FIV infection, while 5 of 14 control cats were infected. Thus, the vaccine was safe and immunogenic and did not transmit infection. Furthermore, vaccinated cats did not develop FIV infection in a limited clinical trial over an extended time period. Thus, the data suggest that a fixed, FIV-infected cell vaccine has potential for preventing natural FIV infection in free-roaming cats.

Phenotype-genotype correlation in Sicilian patients with Hb H

We studied 15 Sicilian subjects with Hb H disease correlating clinical examinations with hematological and molecular data. Seven different alpha-tha1 mutations were identified: four deletion types (--MED --CAL, -alpha3.7, -alpha4.2) and three nondeletion types (alpha(Ncol)alpha, alpha(Hph)alpha, alphaCSalpha). All the patients had a zero-gene chromosome (--MED or --CAL), while the third alpha gene was deleted (-alpha3.7, -alpha4.2) or inactive (alpha(Ncol)alpha, alpha(Hph)alpha, alphaCSalpha). In patients with the nondeletion genotype the analysis of hematological values revealed lower levels of RBC and Hb A2 and significantly higher levels of Hb H. The clinical variability was remarkable, ranging from totally asymptomatic conditions, casually diagnosed, to severe thalassemia intermedia with marked hemolytic crises, liver and spleen enlargement and the necessity for frequent transfusions. The genotype did not justify the gravity of the phenotype in every case, and the differences in clinical manifestations, also notable, are not easily explainable in subjects who apparently have the same genotype.

N-Methyl-D-aspartate receptor stimulation activates tyrosinase and promotes melanin synthesis in the ink gland of the cuttlefish Sepia officinalis through the nitric Oxide/cGMP signal transduction pathway. A novel possible role for glutamate as physiologic activator of melanogenesis

The tyrosinase-catalyzed conversion of l-tyrosine to melanin represents the most distinctive biochemical pathway in the ink gland of the cuttlefish Sepia officinalis; however, the molecular mechanisms underlying its activation have remained so far largely uncharted. In this paper we demonstrate for the first time that l-glutamate can stimulate tyrosinase activity and promote melanin synthesis in Sepia ink gland via the N-methyl-d-aspartate (NMDA) receptor/NO/cGMP signal transduction pathway. Incubation of intact ink glands with either l-glutamate or NMDA resulted in an up to 18-fold increase of tyrosinase activity and a more than 6-fold elevation of cGMP levels. Comparable stimulation of tyrosinase was induced by an NO donor and by 8-bromo-cGMP. An NMDA receptor antagonist, NO synthase (NOS) inhibitors, and a guanylate cyclase blocker suppressed NMDA-induced effects. Immunohistochemical evidence indicated that enhanced cGMP production was localized largely in the mature part of the ink gland. Increased de novo synthesis of melanin was demonstrated in NMDA- and NO-stimulated ink glands by a combined microanalytical approach based on spectrophotometric determination of pigment levels and high performance liquid chromatography quantitation of pyrrole-2,3, 5-tricarboxylic acid, a specific melanin marker, in melanosome-containing fractions. These results fill a longstanding gap in the understanding of the complex biochemical mechanisms underlying activation of melanogenesis in the mature ink gland cells of S. officinalis and disclose a novel physiologic role of the excitatory neurotransmitter glutamate mediated by the NMDA receptor/NO/cGMP signaling pathway.

Doubling of the epirubicin dosage within the 5-fluorouracil, epirubicin and cyclophosphamide regimen: a prospective, randomized, multicentric study on antitumor effect and quality of life in advanced breast cancer

In metastatic breast cancer (MBC) doubling the epirubicin (EPI) dose intensity (DI) within the FEC (5-fluorouracil, EPI, cyclophosphamide) regimen could increase the response rate (RR) and ameliorate the quality of life (QoL) over standard FEC. From May, 1995, 74 consecutive patients with MBC were randomly treated with 6 courses of two FEC regimens containing 60 (60FEC) or 120 (120FEC, supported by primary G-CSF) mg/m2 of EPI. Drugs were administered every 21 days. The QoL was assessed over and after treatment by the EORTC QLQ-C30 (VER 2.0) and QLQ-BR23 questionnaires, compiled by the patient, and the Spitzer's QL-index, compiled by the physician. The study was prematurely closed in May, 1997, due to RR and QoL data of 4th interim analysis. The delivered EPI DI was 20.0 and 37.9 mg/m2/week in 60- and in 120FEC, respectively. Among the two regimens, there was no statistically significant difference in RR or in improvement of baseline overall QoL. With respect to 60FEC patients, the 120FEC patients had longer time to progression (19.2 vs 13.1 mos, p=0.04). Over baseline, the 120- but not the 60FEC patients had significantly greater pain decrease and lower deterioration of body image. In MBC, both 60- and 120FEC regimens furnished the same RR and improvement in overall baseline QoL. With respect to 60FEC patients, the 120FEC patients experienced longer time to progression. Over baseline, pain decrease and preservation of body image were also greater in these patients.

Seroprevalence of Chlamydia pneumoniae antibodies in a young adult population sample living in Verona. European Community Respiratory Health Survey (ECRHS) Verona

The aim of the study was to evaluate the prevalence of antibodies to Chlamydia pneumoniae in a random population sample of 369 young adults (aged 20-44 years), living in Verona, Italy. IgG and IgM titers were measured by micro-immunofluorescence. IgG antibodies, greater or equal to 16, were found in 104/177 (58.8%) men and 76/192 (39.6%) women (p < 0.001). No relationship was found between IgG seropositivity, age, social class, education and family size. Factors positively associated with IgG seropositivity included smoking (p < 0.001), occupational status (employed vs unemployed: p = 0.02; students vs unemployed: p < 0.01) and living area (suburban [65.0%] vs urban area [45.3%]: p = 0.03). The geometric mean of IgG titers was higher in students (GM: 26.05) than in both employed (GM: 11.02) and unemployed persons (GM: 4.80) (p < 0.01 and p < 0.001, respectively). IgG titres > or = 512 and/or IgM titers > or = 16 (suggestive of a recent C. pneumoniae infection) were found in 39 subjects (10.6%). Recent infection was more frequent in spring (14.9%), with no significant variation in the other seasons (mean prevalence 6.7%) (p < 0.01). Recent infection was also associated with cigarette smoking. On the other hand, no significant association was found between respiratory symptoms and serologic evidence of recent infection.

IN CONCLUSION

1) the prevalence of antibodies to C. pneumoniae in young adults from Verona is similar to that found in European countries, and therefore, in Europe, it seems not related to latitude or climate; 2) male sex, tobacco smoking, employment status and living in a suburban area are independent risk factors of infection; 3) the infection is subclinical in most cases.

Serious childhood respiratory infections and asthma in adult life. A population based study. ECRHS Italy. European Community Respiratory Health Survey

BACKGROUND

A number of epidemiologic studies have tried to establish whether respiratory tract infections in early childhood cause obstructive pulmonary disease in adult life.

OBJECTIVE

To determine whether reported serious respiratory infection before the age of 5 years (SRI) is a significant risk factor for subsequent development of bronchial asthma and/or bronchial hyperresponsiveness in adults.

METHODS

We investigated a random population sample of 1,104 subjects (aged 20 to 40 years), participating in the European Respiratory Health Survey in Italy. Bronchial response to methacholine and answers to a standardized questionnaire were analyzed.

RESULTS

The prevalence of SRI (ie, a positive response to the question "Have you ever had a serious respiratory infection before the age of 5 years?") was significantly higher in the subjects with a positive family history of allergic diseases than in those with a negative one (O.R. 1.89; 95% C.I. 1.24 to 2.87, P < .01). No relationship was found between SRI and current adult asthma; however, asthma in the past was found in 20.5% of the SRI positive subjects and in 9.1% of SRI negative subjects (O.R. 2.47; 95% C.I. 1.47 to 4.15, P < .05). No difference in the response to methacholine and in FEV1, FEV1/FVC values was found between SRI positive and SRI negative subjects.

CONCLUSIONS

We suggest that a positive family history of atopy is associated with a significantly higher prevalence of SRI. Furthermore our results indicate that exposure to SRI is a risk factor for asthma in the past (ie, asthma in childhood and adolescence) but not for adult asthma or for the development of bronchial impairment in adult life.

Survey of canine and feline follicular tumours and tumour-like lesions in central Italy

Between January 1985 and June 1997, a total of 4005 skin biopsies were received from dogs and 898 from cats. Follicular tumours and tumour-like lesions together represented 10.4 per cent and 8.1 per cent of all skin tumours in the dog and cat, respectively. The prevalence of tumour-like lesions, such as follicular and dermoid cysts, dilated pore and focal adnexal dysplasia, was highest, representing 41.2 per cent and 68 per cent of all follicular lesions in dogs and cats, respectively. In the dog, follicular tumours were distributed as follows: trichoblastoma (25.6 per cent of all tumours and tumour-like lesions), infundibular keratinising acanthoma, (14 per cent), pilomatricoma (13 per cent), trichoepithelioma (3.9 per cent) and tricholemmoma (2.3 per cent). In the cat, the distribution was 26 per cent for trichoblastoma, 4 per cent for trichoepithelioma and 2 per cent for pilomatricoma. Tumour-like lesions and infundibular keratinising acanthoma in the dog were mostly located on the trunk, trichoblastoma and tricholemmoma on the head, and pilomatricoma on the neck. In the cat, both tumour-like lesions and trichoblastoma were frequently present on the neck and head.

Tumor necrosis factor-alpha and virus expression in the central nervous system of cats infected with feline immunodeficiency virus

Cytokine disregulation has been implicated in the pathogenesis of lentivirus-induced diseases. In the present study, 18 specific pathogen free (SPF) cats were inoculated with feline immunodeficiency virus (FIV) Petaluma strain and sacrificed at different times post-infection. Five additional SPF cats were used as controls. The cell localization of the cytokine tumor necrosis factor alpha (TNF-alpha) in the central nervous system (CNS) was determined by immunohistochemical and morphometric analyses with a polyclonal rabbit anti-human TNF-alpha antibody. TNF-alpha and FIV RNA were measured using competitive reverse transcriptase polymerase chain reaction (PCR) assays and the number of proviral genomes was estimated by competitive PCR. Portions of frontal cortex were collected from each animal and both formalin-fixed and snap-frozen and stored at -80 degrees C until used. The results showed that TNF-alpha is present mainly in astrocytes and microglial cells. Morphometric analysis showed that areas of TNF-alpha production increased in the early phases of infection. Molecular analyses demonstrated that the kinetics of proviral loads in the CNS were comparable to what observed in lymph nodes and peripheral blood mononuclear cells, with the peaks in the early and late stages of infection. A positive correlation was found between viral parameters and TNF-alpha transcription, the strongest relationship was found between the transcription of the cytokine and viral RNA load. These results confirm that invasion of CNS by FIV occurs soon after virus exposure and that during this phase there is an increase of local viral loads with concomitant up-regulation of TNF-alpha expression. During the asymptomatic phase viral replication remains low in spite of the progression of CNS alterations. The dissociation between the viral load and the lesions observed suggests the importance of an indirect mechanism for the progression of these lesions, even if TNF-alpha seems to play a role particularly in the early phase of infection.

A calcium/calmodulin-dependent nitric oxide synthase, NMDAR2/3 receptor subunits, and glutamate in the CNS of the cuttlefish Sepia officinalis: localization in specific neural pathways controlling the inking system

Chemical, biochemical, and immunohistochemical evidence is reported demonstrating the presence in the brain of the cuttlefish Sepia officinalis of a Ca2+-dependent nitric oxide synthase, NMDAR2/3 receptor subunits, and glutamate, occurring in neurons and fibers functionally related to the inking system. Nitric oxide synthase activity was concentrated for the most part in the cytosolic fraction and was masked by other citrulline-forming enzyme(s). The labile nitric oxide synthase could be partially purified by ammonium sulfate precipitation of tissue extracts, followed by affinity chromatography on 2',5'-ADP-agarose and calmodulin-agarose. The resulting activity, immunolabeled at 150 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis by antibodies to rat neuronal nitric oxide synthase, depended on NADPH and tetrahydro-L-biopterin, and was inhibited by N(G)-nitro-L-arginine. NMDAR2/3 subunit-immunoreactive proteins migrating at 170 kDa could also be detected in brain extracts, along with glutamate (whole brain: 0.32 +/- 0.03 micromol of glutamate/mg of protein; optic lobes: 0.22 +/- 0.04; vertical complex: 0.65 +/- 0.06; basal lobes: 0.58 +/- 0.04; brachial lobe: 0.77 +/- 0.06; pedal lobe: 1.04 +/- 0.08; palliovisceral lobe: 0.86 +/- 0.05). Incubation of intact brains with 1.5 mM glutamate or NMDA or the nitric oxide donor 2-(N,N-diethylamino)diazenolate-2-oxide caused a fivefold rise in the levels of cyclic GMP, indicating operation of the glutamate-nitric oxide-cyclic GMP signaling pathway. Immunohistochemical mapping of Sepia CNS showed specific localization of nitric oxide synthase-like and NMDAR2/3-like immunoreactivities in the lateroventral palliovisceral lobe, the visceral lobe, and the pallial and visceral nerves, as well as in the sphincters and wall of the ink sac.

Pharmacological characterization of adenosine A1 receptors and its functional role in brown trout (Salmo trutta) brain

The adenosine receptor agonist N(6)-cyclohexyl[(3)H]adenosine ([(3)H]CHA) was used to identify and pharmacologically characterize adenosine A1 receptors in brown trout (Salmo trutta) brain. In membranes prepared from trout whole brain, the A1 receptor agonist [(3)H]CHA bound saturably, reversibly and with high affinity (K(d)=0. 69+/-0.04 nM; B(max)=0.624+/-0.012 pmol/mg protein) to a single class of binding sites. In equilibrium competition experiments, the adenosine agonists and antagonists all displaced [(3)H]CHA from high-affinity binding sites with the rank order of potency characteristic for an adenosine A1 receptors. A1 receptor density appeared not age-related (from 3 months until 4 years), and was similar in different brain areas. The specific binding was inhibited by guanosine 5'-triphosphate (IC(50)=0.778+/-0.067 microM). GTP (5 microM) induced a low affinity state of A1 receptors. In superfused trout cerebral synaptosomes, 30 mM K(+) stimulated the release of glutamate in a calcium dependent manner. Glutamate-evoked release was dose-dependently reduced by CHA, and the inhibition was reversed by the A1 antagonist 8-cyclopentyltheophylline (CPT). In the same synaptosomal preparation, 30 mM K(+) as well as 1 mM glutamate stimulated the release of adenosine in a Ca(2+)-independent manner and tetrodotoxin insensitive. These findings show that in trout brain adenosine A1 receptors are present which are involved in the modulation of glutamate transmitter release. Moreover, the stimulation of adenosine release by K(+) depolarisation or glutamate support the hypothesis that, as in mammalian brain, a cross-talk between adenosine and glutamate systems exists also in trout brain.

Predominant expression of group-II metabotropic glutamate receptors in the goldfish brain

Group-II metabotropic glutamate (mGlu) receptors (mGlu2/3 receptors) were highly expressed in various regions (telencephalon, optic tectum, and cerebellum, but not vagal lobe) of the goldfish brain. In the goldfish telencephalon, expression of mGlu2/3 receptors was even higher than in the rat cerebral cortex. In contrast, mGlu5 receptors showed low levels of expression in all goldfish brain regions, whereas mGlu1a receptors were only expressed in the goldfish cerebellum. Pharmacological activation of group-II mGlu receptors with the selective agonists, 2R,4R-4-aminopyrrolidine-2, 4-dicarboxylic acid and (2S,2'R,3'R)-2-(2,3-dicarboxycyclopropyl) glycine, reduced the evoked release of glutamate from goldfish brain synaptosomes, whereas agonists of group-I and -III mGlu receptors (3, 5-dihydroxyphenylglycine and L-2-amino-4-phosphonobutanoate) were inactive. The predominance of group-II over group-I mGlu receptors in the goldfish brain may provide a natural defense against excitotoxic neuronal death and contribute to the unusually high resistance of goldfish against hypoxic brain damage.

Effects of triflusal on arteriosclerosis progression assessed with high-resolution arterial ultrasound

In order to evaluate the effect of triflusal (2-acetyloxy-4-trifluoromethyl benzoic acid), an orally active antiplatelet agent, on arteriosclerosis progression, a pilot, parallel, double-dummy, double-blind clinical trial vs acetylsalicylic acid (ASA) was carried out in patients with subclinical atherosclerotic lesions. The trial consisted of a 2-week run-in placebo phase, followed by a 12-month oral treatment with triflusal (600 mg/day) or ASA (300 mg/day). The primary variable was identified in the ultrasonic biopsy (UB) score; the secondary variables were the UB class changes of each arterial site, the rate of progression (ROP), the intima-media thickness (IMT), and the symptoms of arteriosclerosis. Data were evaluated by use of analysis of variance and Chi-square test. Forty-three patients (31 men, 12 women, mean age 62.8 +/- 8.4 SD) were randomized to triflusal (15 men, 6 women, mean age 64.3 +/- 6.7) or to ASA (16 men, 6 women, mean age 61.3 +/- 9.6). The analysis of variance on the UB score showed no difference between treatments: the patients' UB scores remained unchanged with no progression, thus indicating that no patient worsened during treatment. When all arterial sites under evaluation are considered, 86% of the sites in the triflusal group and 85% in the ASA group remained unchanged. No relevant change was recorded in vital signs and routine laboratory tests. Gastric disturbances were reported by two and three patients treated with triflusal and ASA, respectively. In conclusion, triflusal appears as effective as ASA in slowing arteriosclerosis progression.

Alpha-dihydroergocryptine in the prophylaxis of migraine: a multicenter double-blind study versus flunarizine

This multicenter, double-blind, clinical study was designed to compare the efficacy and safety of alpha-dihydroergocryptine and flunarizine in the prophylaxis of migraine without aura. One hundred thirty-five patients fulfilling the diagnostic criteria of the International Headache Society were enrolled at five neurologic centers. The study design included a 1-month pretreatment phase with placebo; a 6-month, double-blind, double-dummy treatment phase with alpha-dihydroergocryptine (10 mg twice daily) or flunarizine (5 mg once daily); a further 3-month follow-up phase without treatment. Efficacy was assessed using the patient's diary. Laboratory tests, vital signs, and adverse events were monitored. Analysis of covariance for repeated measures was performed on the intent-to-treat sample. Both treatments led to a significant reduction in the frequency of migraine, days with headache, and use of relief medication. Overall, 51% of those treated with alpha-dihydroergocryptine and 49% of those treated with flunarizine were responders (50% or greater reduction in attack frequency), the average percentage of reduction being 64% with alpha-dihydroergocryptine and 51% with flunarizine. There was no significant difference between the two groups in terms of incidence of adverse events; dizziness and weight gain were the most frequent observed adverse events with alpha-dihydroergocryptine and flunarizine, respectively. Based on the overall improvement in migraine parameters, alpha-dihydroergocryptine can be recommended for use in migraine prophylaxis.

Comparison of dobutamine stress echocardiography and exercise stress Thallium-201 SPECT for detection of myocardial ischemia after acute myocardial infarction treated with thrombolysis

In order to compare the ability of dobutamine stress echocardiography (DSE) and exercise Thallium-201 SPECT to detect myocardial ischemia in patients with myocardial infarction (MI) treated with thrombolysis, 43 prospectively selected patients with MI treated with thrombolysis underwent within 1 month from MI DSE, stress-redistribution-reinjection Thallium-201 SPECT and coronary angiography. The echocardiographic and scintigraphic images were analyzed for the presence of myocardial ischemia using a 11-segment left ventricular model. DSE and exercise Thallium-201 SPECT detected myocardial ischemia in the infarct zone in 72% and 72% (31/43) of patients and ischemia at a distance in 12% (5/43) and 19% (8/43) of patients with a concordance of 67% and 88%, respectively. A significant agreement between DSE and exercise Thallium SPECT was found in the evaluation of the extent of both myocardial necrosis and stress-induced myocardial ischemia. DSE and exercise Thallium SPECT showed similar sensitivity (79 vs 76%), specificity (60 vs 60%) and accuracy (77 vs 74%) for detection of a critical stenosis of the infarct-related artery; there was also no significant difference between the tests in sensitivity, specificity and accuracy for detection of the multivessel disease. In conclusion, initially after thrombolyzed MI, DSE and exercise Thallium-201 SPECT detect myocardial ischemia in the infarct zone in a high proportion of patients and show a similar accuracy for the diagnosis of a critical stenosis of the infarct-related coronary artery and of the multivessel disease.

Antithrombotic therapy of unstable angina and non-Q-wave myocardial infarction

Unstable angina and non-Q-wave myocardial infarction still represent an unsolved problem for clinicians, owing to their unpredictable evolution and high incidence of coronary events in the follow-up. Traditional antithrombotic agents, unfractionated heparin and aspirin, have been proved to be highly effective, but show some important limitations. New potent antithrombotic therapy have been studied to improve their efficacy, with encouraging results. Among these drugs, low molecular weight heparins (for subcutaneous administration) and inhibitors of platelet glycoprotein receptor IIb/IIIa (for intravenous, and possibly oral, administration) are the most promising and are now under extensive investigation.

Adjunctive stent implantation following directional coronary atherectomy in patients with coronary artery disease

OBJECTIVES

This prospective case-control study evaluated the acute and long-term results of stent implantation preceded by debulking of the plaque by means of directional coronary atherectomy.

BACKGROUND

In comparison with balloon angioplasty, intracoronary stenting produces a larger luminal diameter, maintains artery patency and reduces the incidence of restenosis. Optimal stent deployment is a pivotal factor for achieving the best results, but the bulk of the atherosclerotic plaque opposes stent expansion and may limit the success of the procedure. Debulking of the plaque may provide a better milieu for optimal stent deployment.

METHODS

Directional coronary atherectomy followed by a single Palmaz-Schatz stent implantation was attempted in 100 patients. The successes, complications and angiographic results of the combined procedure were evaluated both acutely and during follow-up. Matched patients undergoing successful Palmaz-Schatz stent implantation alone during the same period served as controls.

RESULTS

Atherectomy followed by stent implantation was performed in 94 patients with 98 lesions; periprocedural complications were observed in four cases. The stenosis diameter decreased from 76+/-9% at baseline to 30+/-13% after atherectomy (p < 0.0001), and 5+/-9% after stent implantation (p < 0.0001); it increased to 27+/-15% at 6-month angiography (p < 0.0001). During the 14+/-10 months of follow-up, none of the patients died or experienced myocardial infarction, but three patients underwent target lesion revascularization. The patients undergoing stent implantation alone achieved smaller acute gains, tended to have a higher late lumen loss, had a higher restenosis rate (30.5% vs. 6.8%, p < 0.0001) and showed a greater incidence of clinical events during follow-up (p < 0.0001).

CONCLUSIONS

Debulking atherosclerotic lesions by means of directional coronary atherectomy before stent implantation is a safe procedure with a high success rate and a low incidence of restenosis at follow-up.

Antioxidants and coronary artery disease

Data on the protective role of antioxidants in models of atherosclerosis are only partially confirmed in man. Observational and epidemiological data, as well as randomized trials, provide no clear cut indications, because of positive and disappointing results on the use of antioxidants in cardiovascular protection. Despite the lack of a general consensus, recent data reinforce the concept that the regular intake of antioxidants present in food limits the progression of atherosclerosis. When it is possible to monitor the efficacy of any antioxidant therapy with validated markers of oxidation, the potential influence of vitamins and antioxidants on coronary artery disease may eventually be resolved.

Prevalence of asthma and asthma-like symptoms in an adult population sample from Verona. ECRHS Verona. European Community Respiratory Health Survey

The aim of the study was to assess the prevalence of asthma and asthma-like symptoms in the general population of Verona. A screening questionnaire, with seven questions on respiratory symptoms, was sent by mail to 3000 randomly selected subjects, aged 20-44 yrs. After three subsequent mailings, nonresponders were interviewed by telephone. The overall response rate was 92%. At least one respiratory symptom was reported by 44% subjects. The prevalence of the most frequent symptoms differed according to the type of contact: early respondents (i.e. those who responded by mail) were more likely to report symptoms than late respondents (i.e. those who were interviewed by telephone). Wheezing was reported by 11.3% of males and 8.0% of females (p < 0.01). The allergic rhinitis and hay-fever prevalence was 16.9% with no differences owing to sex or age. The prevalence of an "episode of asthma" (defined as a self-reported attack of asthma or treatment for asthma) and of "current asthma" (defined as a self-reported attack of asthma, treatment for asthma or wheezing other than due to a cold with dyspnoea in the last 12 months) was 4.1 and 4.7%, respectively. No differences were found on the basis of age and sex. The prevalence of asthma was greater in urban (5.0%) than in suburban (2.7%) areas (p < 0.05), where lower pollution levels were registered. The greater prevalence in urban areas suggests that some factors related to the urban environment could play a role in the development of asthma and asthma-like disorders.

Neospora caninum infection in a Bernese cattle dog from Italy

A cutaneous nodule associated with Neospora caninum infection was diagnosed in a 5-year-old male Bernese cattle dog from Italy. The ulcerative lesion was 2-3 cm wide located in the skin of the tarsal region. Haematological values were normal and the dog did not show any neurological abnormalities. The dermal lesion consisted of a diffuse necrotic dermatitis with a dense infiltrate of mostly neutrophils and macrophages, surrounded by a fibrous wall. Histological sections revealed numerous tachyzoites of N. caninum scattered throughout the tissue. Diagnosis was confirmed both by immunohistochemical staining and electron microscopic examination. The dog had a 1:640 IFAT titre to N. caninum. Four weeks after surgical excision new subcutaneous nodules reappeared. The cutaneous lesions resolved following 21 days of therapy with clindamycin hydrochloride. These observations demonstrate the presence of N. caninum in Italy and confirm that neosporosis should be considered in the differential diagnosis of pyogranulomatous dermatitis in dogs. Clindamycin may be an effective treatment for cutaneous neosporosis.

Detection of feline immunodeficiency proviral sequences in lymphoid tissues and the central nervous system by in situ gene amplification

The availability of sensitive methods for detecting and localising the feline immunodeficiency virus (FIV) may help shed light on its role in generating tissue damage observed during infection. As immunohistochemical and in situ hybridisation techniques might not be sufficiently sensitive for this type of study, we adapted to FIV PCR-in situ hybridisation (PCR-ISH) that combine the extreme sensitivity of PCR with the precise localisation provided by ISH. The steps important for the success of PCR-ISH, such as sample preparation, permeabilisation, amplification profile, type of labels, and hybridisation conditions were optimised using paraformaldehyde-fixed and formalin-fixed paraffin-embedded sections of cells infected in vitro with FIV. As controls for amplification, the feline tumor necrosis factor-alpha gene (TNF-alpha) and the non-related EBNA-1 gene of the human Epstein-Barr virus were used. Once the method proved sufficiently sensitive and specific with these cells, the PCR-ISH assay was applied to paraffin sections of the lymph nodes, spleen and central nervous system of a 2-year FIV infected cat that, at the time of challenge, harboured low copy numbers of proviral genomes. Comparison of the results of PCR-ISH, competitive PCR and immunohistochemical analysis are described.

[Coronary lesion with an aneurysm: their correction via angioplasty and the implantation of a coated stent]

We describe the good angiographic results obtained using a new polymeric prosthesis combining a stent with expandable polytetrafluoroethylene (PTFE) graft material in the treatment of proximal left descending coronary artery stenosis complicated by the presence of a coronary aneurysm.

Nitroflurbiprofen, a new nonsteroidal anti-inflammatory, ameliorates structural injury in the remnant kidney

Cyclooxygenase derivatives and nitric oxide (NO) may influence the pathogenesis of progressive nephropathies. We investigated the effect of nitroflurbiprofen (NOF), a NO-releasing nonsteroidal anti-inflammatory drug (NSAID) without gastrointestinal toxicity, in rats with 5/6 ablation (NX). The following four groups were studied: Sham, sham-operated rats; Sham + NOF, Sham receiving oral NOF two times daily; NX, rats subjected to NX; and NX + NOF, NX receiving NOF. NOF was barely detected in plasma but released the parent compound flurbiprofen. At 30 days, glomerular hydraulic pressure (PGC) was 76 +/- 3 mmHg in NX (52 +/- 1 in Sham, P < 0.05). NOF slightly reduced PGC to 69 +/- 2 mmHg in NX + NOF (P > 0.05 vs. NX). Glomerular volumes behaved similarly. At 60 days, tail cuff pressure was 152 +/- 6 mmHg, glomerulosclerosis index was 22.1 +/- 9.5, and interstitial fractional area was 9.9 +/- 1.2% in NX. NOF reduced these parameters to 137 +/- 4 mmHg, 3.5 +/- 0.7, and 6.4 +/- 0.8%, respectively (P < 0.05), without causing growth stunting or anemia. These beneficial effects could not be ascribed to NO donation and may reflect cyclooxygenase inhibition. This is the first evidence that chronic NSAID treatment may ameliorate progressive nephropathies.

Effect of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine in goldfish cerebellum: neurochemical and immunocytochemical analysis

1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) administered in goldfish for 3 consecutive days (10 mg kg-1 i.p.), caused cerebellar disappearance of dopamine-hydroxylase (DBH) immunoreactive fibres, whereas the noradrenergic cell bodies located in the medulla oblongata appeared intact. This effect was coupled with marked decreases in cerebellar noradrenaline (NA) and dopamine (DA) levels. An increase of immunostaining for glial fibrillary acidic protein (GFAP) was also observed. In the cerebellum of MPTP-treated fish, the contents of glutamate and GABA were significantly reduced, whereas glutamine was strongly increased. These modifications were concomitant with a significant increase of glutamine synthetase (GS) activity, whereas glutamic acid decarboxylase (GAD) activity was decreased. No changes in choline acetyltransferase (ChAT) and ornithine decarboxylase (ODC) activities were observed. High affinity uptake of glutamate and GABA was strongly reduced. Pretreatment of fish with either the monoamine oxidase inhibitor pargyline or the catecholamine (CA) uptake blocker mazindol largely prevented such modifications. The NMDA-sensitive glutamate receptor uncompetitive antagonist, dizocilpine maleate (MK-801), failed to protect against MPTP-induced damage. In conclusion, the neurotoxic effects of MPTP in goldfish cerebellum appear to be not specific against catecholaminergic terminals and could promote astrocytic reactions.

Ultrastructure of the cyst wall of Sarcocystis sp. in roe deer

Samples of heart, tongue, oesophagus and diaphragm muscle from twenty-two naturally infected roe deer (Capreolus capreolus) harvested in central Italy were examined for sarcosporidiasis. The structure of Sarcocystis spp. muscle cysts was examined by light and electron microscopy. Only one type of thin-walled cyst was distinguished by light microscopy. Electron microscopy showed cysts having a thin highly folded primary cyst wall, without fibrillar material, that formed thin hair-like protrusions often having a T-form, especially close to host cell mithocondria. The cysts appeared to belong to a single Sarcocystis sp. so that all the animals had monospecific infections. This cyst was compared with cysts described in other cervid in an attempt to determine if single or multiple species of the genus Sarcocystis occur in the Cervidae. Apparently, a single Sarcocystis sp. with a low specificity for the intermediate host can infect the Cervidae.

Neuropathology in cats experimentally infected with feline immunodeficiency virus: a morphological, immunocytochemical and morphometric study

Neuropathological changes have been described associated with feline immunodeficiency virus (FIV) infection. The objective of our study was to characterize the lesions found in the brain and spinal cord of experimentally FIV-infected cats and to quantify, by morphometric analysis, the intensity of gliosis found in these subjects at different time post infection (pi). The brains and spinal cords appeared grossly normal. Gray matter of cortical and subcortical structures showed a moderate to pronounced gliosis particularly in all cerebral cortex and hippocampus. Morphometric analysis demonstrated that GFAP immunoreactivity was markedly higher in infected animals. Gliosis was present 15 days pi and did not appear to progress during the infection, whereas neuronal changes when present were observed only in long-term infected animals (15-23 months pi). In a large proportion of infected cats a diffuse gliosis of white matter and vacuolar myelinopathy was also present. Despite some discrepancies observed between neuropathological changes in FIV-infected animals and HIV-infected individuals, the presence in the cerebral cortex of cats with FIV infection of alterations similar to those observed in AIDS patients demonstrates that FIV is an interesting animal model particularly that may be useful for clarifying the pathogenesis of neuropathological changes associated with HIV infection.

Comparison of aminosidine (paromomycin) and sodium stibogluconate for treatment of canine leishmaniasis

Twelve dogs naturally infected with Leishmania infantum were treated subcutaneously with aminosidine at a dose of 10 mg kg-1 per day for four weeks. Antimonial compounds were used as reference drugs in twelve Leishmania-infected dogs. Eleven of the twelve dogs submitted to aminosidine therapy responded within 30 days. The treatment with the aminoglycoside antibiotic presented a marked decrease of anti-Leishmania antibody titres than the controls. Aminosidine also reduced urinary protein, serum IgG, and circulating immune complex concentrations. Side effects were observed only in a dog with pre-existent renal lesions. This study proved that aminosidine is an effective, tolerable and safe drug for the treatment of canine leishmaniasis and that it could be used as a suitable substitute for antimonial therapy.

Comparative bioavailability of two atenolol tablet formulations in healthy male volunteers after a single dose administration

The bioavailability of 2 atenolol tablet formulations (Angipress from Laboratórios Biosintética, and Atenol from Wellcome ICI Laboratory, Brazil) were compared in 18 healthy male volunteers who received a single 50 mg dose of each atenolol formulation. The study was conducted following an open randomized 2-period crossover design with a 14-day washout interval between doses. Plasma samples were obtained over a 24-hour interval and atenolol concentrations were determined by HPLC with fluorimetric detection. From the plasma atenolol concentration vs time curves the following pharmacokinetic parameters were obtained: AUC(zero-24) (area under the concentration vs time curves from 0-24 h), ke (terminal elimination constant), t1/2 (terminal first order elimination half-life), AUC (area under the concentration vs time curves extrapolated to infinity), Cmax (maximum achieved concentration), Tmax (time to achieve Cmax) and Cmax/AUC. All these variables were analyzed using both parametric and nonparametric statistics. Geometric mean Angipress/Atenol individual percent ratios were 99.6% for AUC(zero-24), 99.7% for AUC, 98.0% for Cmax, 102.8% for t1/2, 97.2% for ke and 97.8% for Cmax/AUC, with all their 90% confidence intervals within the bioequivalence range 80-125%, thus showing similar patterns of absorption and disposition. Arithmetic mean for individual Tmax differences was 0.8 h, and the 90% confidence interval did not include the zero value. Based on these results and in accordance with the European Union and the US Food and Drug Administration bioequivalence requirements we conclude that both atenolol formulations are bioequivalent for both the extent and the rate of absorption.

[Surgical treatment of spontaneous pneumothorax: comparison of thoracotomy and thoracoscopy]

The video-thoracoscopic treatment of spontaneous pneumothorax currently has the same role of laparoscopic cholecystectomy in abdominal surgery. The Authors consider thoracoscopic approach and traditional thoracotomy examining advantages versus disadvantages, comparing 50 patients with spontaneous pneumothorax treated by thoracoscopy, from February 1992 up to February 1995, and 50 patients, previously treated by open surgery. Video-thoracoscopy has the same percentage of recurrences of thoracotomic approach but assures a quicker functional recovery and, above all, a remarkable reduction of pain.

Neurochemical changes in cerebellum of goldfish exposed to various temperatures

Acclimation of goldfish at 35 degrees C increased the cerebellar content of aspartate, glutamate, and taurine and [3H]glutamate uptake. Acclimation at 4 degrees C increased the levels of glutamine, serine, and alanine and glutamine synthetase (GS) activity. Adenosine content increased in cerebellum of fish acclimated to warm temperature. K+-evoked release of endogenous and exogenous glutamate from cerebellar slices increased in fish acclimated at 35 degrees C compared to 4 degrees C. The basal level of cyclic adenosine 3':5'-monophosphate (cAMP) in perfused cerebellar slices in fish acclimated at 35 degrees C was much higher than in fish acclimated at 5 degrees and 22 degrees C. It is concluded that variations of environmental temperature produces large neurochemical changes in goldfish cerebellum.

Evaluation of dot enzyme-linked immunosorbent assay (dot-ELISA) for the serodiagnosis of canine leishmaniosis as compared with indirect immunofluorescence assay

A dot enzyme-linked immunosorbent assay (dot-ELISA) was developed and compared with a standard indirect immunofluorescence assay (IFA) for the rapid serodiagnosis of canine leishmaniosis. The two tests were used to examine sera from Leishmania infantum-infected and control dogs. Using the dot-ELISA, 137 of 149 sera (91.9%) from infected animals gave a clearly positive reaction, whereas in the standard IFA technique 147 (98.7%) were positive at a reciprocal titer of 40 or over (titer range 40-10,240). Control sera from 75 healthy dogs, not living in endemic areas, and 11 dogs with other diseases (babesiosis, cryptococcosis, ehrlichiosis, dermatitis, and chronic hepatitis) but Leishmania-negative were used to determine the specificity of the assays. All the sera were negative with IFA (100%), whereas using the dot-ELISA only 74 sera (86%) from controls gave a negative result. In the standard IFA no cross-reactivity was noted, in the dot-ELISA a weak cross-reaction was observed with a serum sample from a dog with babesiosis. The interpretation of dot-ELISA could be easily performed by visual inspection of the nitrocellulose disks. The most remarkable feature of dot-ELISA was the high sensitivity (91.9%) and positive predictive value (92.6%), even if the test showed a specificity lower than IFA. Because of its easy performance and high sensitivity, the dot-ELISA may be a useful test to be executed in the field for the diagnosis of canine leishmaniosis.

[Effects of seat belt legislation on injuries of traffic accidents]

This paper reports a comparison of road injuries and fatalities in the twelve months before and after the mandatory enforcement of seat belt buckling (Law no. 143/89) in to area of Verona. In the post-legem period among hospital admitted subjects a significant reduction of injured/accidents ratio was recorded (reduction of 5.3 percent points C.I. 95%: 3.09-7.5 corresponding to a decrease of 29%: p < 0.001) in the same period the number of decreased was lower 12 vs. 19) but the deceased/accidents and the deceased injured ratios were not significantly different. The comparison of distribution of lesions into different body areas showed a sharp decrease of common head trauma (reduction of 14.7 percent point, C.I. 95% 8.20-21.22 corresponding to a decrease of 50.3%: p < 0.001) with a parallel but not significant reduction of subjects with short hospitalization (< or = 3 days. No differences were found for severe trauma frequencies and for overall hospitalization length.

Pharmacokinetic profile and endocrine effects of posatirelin treatment in healthy elderly subjects

The pharmacokinetics and endocrine effects of a therapeutic dose (10 mg/day) of posatirelin (L-pyro-2-aminoadipyl-L-leucyl-L-prolinamide) were investigated in healthy elderly subjects. Posatirelin was given once daily by intramuscular injection for 7 days. Pharmacokinetic parameters were estimated using a model-independent approach. The plasma concentrations of free triiodotyronine (FT3), free thyroxine (FT4), and thyroid-stimulating hormone (TSH) and the circadian rhythms of prolactin and cortisol were considered as indicator variables of endocrine response to posatirelin administration. Posatirelin was well tolerated and no significant adverse effects were observed during the study. Peak plasma concentration (Cmax), time of peak plasma concentration (tmax), area under the plasma concentration-time curve from time zero to infinity (AUC0-infinity), elimination half-life (t1/2), and total clearance (CI/F) were measured after single-dose intramuscular injection (day 1) and after multiple-dose administration (day 7). There were no significant changes in these parameters after multiple-dose administration (day 7). Posatirelin induced a progressive reduction in basal TSH levels and maximum response. There were no significant changes during treatment in the time at which basal levels of FT3 and FT4 occurred, and these levels remained within the normal range throughout the study. The circadian rhythms of cortisol and prolactin were not influenced by posatirelin treatment. The pharmacokinetics of posatirelin were not time dependent, and the drug did not accumulate after multiple-dose administration. Short-term treatment with posatirelin did not induce clinically relevant endocrine consequences in healthy elderly subjects.

Pharmacokinetic Study of Triflusal in Elderly Subjects After Single and Repeated Oral Administration

In this study the single-dose and steady-state pharmacokinetics of unchanged triflusal and its metabolite 2-hydroxy-4-trifluoromethylbenzoic acid (HTB) were studied in 12 elderly subjects treated with a single oral administration of 300 mg triflusal and repeated oral administrations of 300 mg triflusal b.i.d. for 13 days. After a single administration, unchanged triflusal is promptly absorbed (t(max) 0.75 h, C(max) 3.83 &mgr;g/mL) and rapidly depleted from the systemic circulation. Its concentration was measurable only up to 1 to 4 h after administration. The apparent terminal half-life was 0.85 h. HTB proves to be quickly generated from triflusal (t(max) 2.00 h, C(max) 39.88 &mgr;g/mL) and slowly eliminated from the body (t = 54.6 h). With the dose regimen proposed, unchanged triflusal does not accumulate in the body. Conversely, HTB plasma concentration builds up progressively toward steady-state levels of approximately 102 &mgr;g/mL after 4 to 5 d of treatment. No substantial change in peak time, elimination rate constant and half-life evaluated after single-dose treatment was observed on multiple-dose regimen for unchanged triflusal and its metabolite HTB. Therefore, our findings do not indicate a time-dependent pharmacokinetics for triflusal. There were no changes in blood pressure, heart rate or laboratory safety date, i.e., biochemical or hematological profiles.

Pharmacokinetic and Metabolism Study in Healthy Volunteers After Administration of Single Oral Dose of (3)H-alpha-Dihydroergocryptine Mesylate

This phase I open pharmacokinetic and metabolism study was conducted with six healthy male volunteers who were given 20 mg of (3)H-alpha-dihydroergocryptine in order to evaluate the absorption, plasma time course, and urinary and fecal elimination of total radioactivity. Rapid absorption into the general circulation occurred with an average K(01) of 0.99 plus minus 0.73/h. Peak time(T(max)) was reached in approximately 3 h with an average radioactivity concentration (C(max)) of 8.78 plus minus 5.9 ng eq h/ml. Distribution from the central compartment to the peripheral compartment occurred with a mean rate constant (K(12)) of 0.330 plus minus 0.22/h. Estimations of total clearance (CL) and volume of distribution (Vd) seem strongly affected by the low oral availability (F) of hydrogenated ergots. The rate constant (K(21)) of radioactivity washout from the tissue to the central compartment was 0.250 plus minus 0.130/h. However, plasma radioactivity declined biexponentially with an overall elimination constant (K(10)) of 0.029 to 0.146/h (i.e, half-lives of 23.9--4.75/h). Total radioactivity recovery in urine and feces was good with 82.78 plus minus 6.44% of dose eliminated in feces and 3.01 plus minus 0.65% in urine. The latter concentration was too low to detect metabolites or unchanged drug by radioactivity image scanning. However, the liquid scintillation count of silica gel that had been scraped off the thin layer chromatography (TLC) plates indicated the presence of metabolites in urine. Pharmacodynamically, both supine and standing blood pressure fell significantly within the first 8 h of dosing, yet there were no changes in heart rate. No adverse reactions were reported. In conclusion, the kinetics of (3)H-dihydroergocryptine are very similar to other ergot alkaloids in respect to extensive hepatic metabolism with an elimination half-life of 25 h.

Interaction between A1 adenosine and class II metabotropic glutamate receptors in the regulation of purine and glutamate release from rat hippocampal slices

Electrical stimulation of rat hippocampal slices evoked the release of excitatory amino acids and purines, as reflected by a time-dependent increase in the extracellular levels of glutamate and adenosine, as well as by the increased efflux of radioactivity in slices preloaded with both [14C]glutamate and [3H]adenosine. The evoked release of excitatory amino acids and purines was amplified when slices were exposed to 8-cyclopentyl-1,3-dipropylxanthine (a selective A1 adenosine receptor antagonist), (+)-alpha-methyl-4-carboxyphenylglycine [a mixed antagonist of metabotropic glutamate receptors (mGluRs)], or (2S,3S,4S)-2-methyl-2-(carboxycyclopropyl)glycine (a selective antagonist of class II mGluRs). In contrast, 2-chloro-N6-cyclopentyladenosine (CCPA; a selective A1 receptor agonist) or (2S,1R,2R,3R)-(2,3-dicarboxycyclopropyl)glycine (DCG-IV; a selective agonist of class II mGluRs) reduced the evoked release of excitatory amino acids and purines. CCPA and DCG-IV also reduced the increase in cyclic AMP formation induced by either forskolin or electrical stimulation in hippocampal slices. The inhibitory effect of CCPA and DCG-IV on release or cyclic AMP formation was less than additive. We conclude that the evoked release of excitatory amino acids and purines is under an inhibitory control by A1 receptors and class II mGluRs, i.e., mGluR2 or 3, which appear to operate through a common transduction pathway. In addition, although these receptors are activated by endogenous adenosine and glutamate, they can still respond to pharmacological agonists. This provides a rationale for the use of A1 or class II mGluR agonists as neuroprotective agents in experimental models of excitotoxic neuronal degeneration.

Significance of ST-segment elevation during dobutamine-stress echocardiography in patients with acute myocardial infarction treated with thrombolysis

BACKGROUND

Stress-induced ST-segment elevation in patients with recent myocardial infarction treated with thrombolysis has not been extensively investigated. According to the results of previous studies it may represent residual myocardial ischaemia or dyskinesia in the infarcted region. The aim of the study was to analyse the significance of dobutamine-induced ST-segment elevation in the infarcted area in a consecutive group of patients (n = 42, 41 men, mean age 53 +/- 7 years) with a first acute myocardial infarction treated with thrombolysis within 6 h from symptoms onset.

METHODS AND RESULTS

All patients underwent dobutamine-stress echocardiography (up to 40 micrograms.kg-1.min-1 + atropine) 7 +/- 3 days from the acute event and coronary arteriography within 1 month from the test. Significant ST-segment elevation was defined as a shift > or = 1 mm during dobutamine compared to baseline in at least two contiguous infarct-related leads; a correlation was made between the site of ST-segment elevation and wall motion changes during dobutamine. Dobutamine-induced ST-segment elevation in 23/42 (55%) patients (group 1) while no changes were observed in 19/23 (45%) patients (group 2). Compared to group 2, group 1 patients showed a higher asynergy score index (1.72 +/- 0.24 vs 1.50 +/- 0.32, P < 0.02) and a higher number of asynergic segments (5.04 +/- 1.9 vs 4.11 +/- 1.8), at baseline, a higher incidence of baseline and/or stress-induced dyskinesia (39 vs 10%, P < 0.05) in the infarct-related region and a higher percentage of occluded infarct-related arteries (48 vs 0%, P < 0.001). In the 42 patients studied, a significant correlation was found between baseline ST-segment elevation and baseline asynergy score index (RS = 0.56, P < 0.001) and between ST-segment elevation and asynergy score index at peak stress (RS = 0.55, P < 0.001). The incidence of reversible wall motion abnormalities indicative of myocardial viability and residual myocardial ischaemia was similar in the two groups (87 vs 84% and 74 vs 68%, respectively), while the number of segments with irreversible akinesia indicative of myocardial necrosis was higher in group 1 compared to group 2 (1.5 +/- 1.4 vs 0.9 +/- 1.4). Among the 23 patients of group 1 with dobutamine-induced ST-segment elevation, six had no reversible wall motion abnormalities indicative of myocardial ischaemia; of the 17 patients with myocardial ischaemia, 11 had > or = 50% and six had < or = 50% of basally asynergic segments showing reversible wall motion abnormalities.

CONCLUSIONS

In patients with recent thrombolyzed myocardial infarction dobutamine-induced ST-segment elevation is associated with a larger akinetic area in basal conditions and either with reversible wall motion abnormalities indicative of myocardial ischaemia or with irreversible or minimally reversible wall motion abnormalities in the infarct area during the test. Thus, dobutamine echocardiography provides useful information for the interpretation of stress-induced ST-segment elevation and clinical management of these patients.