Biomedical subjects

R Verde

Publications and source records attributed to R Verde.

14 recordsLinked to original sources

PubMed2002

Decreased sensitivity of 5-HT1D receptors in chronic tension-type headache.

OBJECTIVE: To assess the sensitivity of 5-HT1D receptors in chronic tension-type headache using sumatriptan as a pharmacological probe. BACKGROUND: Previous studies have suggested involvement of serotonergic systems in chronic tension-type headache (CTTH), but relevant experimental data are limited. Sumatriptan, a 5-HT1B/1D receptor agonist, stimulates the release of growth hormone (GH) and inhibits the release of ACTH, cortisol, and prolactin. These effects may be used to explore the function of serotonergic systems in vivo. METHODS: We measured GH, ACTH, cortisol and prolactin (PRL) plasma concentrations in 15 patients with chronic tension-type headache and in 18 healthy controls after subcutaneous administration of sumatriptan (6 mg) or placebo. RESULTS: Placebo administration had no effect on hormone concentrations. GH and PRL secretion after sumatriptan administration was significantly (P<0.01 and <0.05) altered in CTTH patients in comparison with controls. CONCLUSION: Our results suggest that cerebral serotonergic functions mediated by 5-HT1D receptors are altered in CTTH.

Adult↗

PubMed1999

Studies of the 48 bp repeat polymorphism of the DRD4 gene in impulsive, compulsive, addictive behaviors: Tourette syndrome, ADHD, pathological gambling, and substance abuse.

Prior studies have reported an association between the presence of the 7 repeat allele of the 48 bp repeat polymorphism of the third cytoplasmic loop of the dopamine D4 receptor gene (DRD4) and novelty seeking behaviors, attention deficit hyperactivity disorder (ADHD), Tourette syndrome (TS), pathological gambling, and substance abuse. However, other studies have failed to replicate some of these observations. To determine whether we could replicate these associations we genotyped 737 individuals from four different groups of control subjects, and 707 index subjects from four different groups of impulsive, compulsive addictive behaviors including substance abuse, pathological gambling, TS, and ADHD. Chi-square analysis of those carrying the 7 allele versus non-7 allele carriers was not significant for any of the groups using a Bonferroni corrected alpha of.0125. However, chi-square analysis of those carrying any 5 to 8 allele versus noncarriers was significant for pathological gambling (p <.0001), ADHD (p </=.01) and the total index group (p </=.0004). When the comparison included all 7 alleles the results were significant for gamblers (p <.0001), TS (p </=.003), ADHD (p </=.003), and the total group (p </=.0002). There was a significant increase in the frequency of heterozygosity versus homozygosity for all alleles for pathological gamblers (p </=.0031) and the total index group (p </=.0015), suggesting that heterosis played a role. In the substance abuse subjects a quantitative summary variable for the severity of drug dependence, based on the Addiction Severity Index, showed that the scores varied by increasing severity across the following genotypes: 44 </= heterozygotes </= 77 </= 22. Studies of other quantitative traits indicated an important role for the 2 allele and the 22, 24, and 27 genotypes. All studies indicated that the role of the DRD4 gene in impulsive, compulsive, addictive behaviors is more complex than a sole focus on the 7 versus non-7 alleles.

Alleles↗

PubMed1999

The proenkephalin gene (PENK) and opioid dependence.

We tested the hypothesis that the alleles at the (CA)n repeat of the proenkephalin gene (PENK) might be associated with opioid addiction in 31 non-Hispanic Caucasian subjects with opioid dependence (heroin), 89 ethnically matched subjects with substance dependence other than opioid dependence and 132 controls. Among the subjects with opioid dependence, 66% carried the > or = 81 bp allele compared with 40% of subjects with other types of substance abuse (chi2 = 11.31, p < 0.004) and 49% of controls (chi2 = 6.0, p < 0.015). These results are consistent with a role of the PENK gene in opioid dependence.

Adult↗

PubMed1999

Homozygosity at the dopamine DRD3 receptor gene in cocaine dependence.

We examined the hypothesis that the dopamine D3 receptor gene (DRD3) is a susceptibility factor for cocaine dependence. The MscI/BalI polymorphism of the DRD3 gene was examined in 47 Caucasian subjects with cocaine dependence and 305 Caucasian controls. Based on prior studies with a range of psychiatric disorders we hypothesized there would be a decrease in the frequency of the 12 genotype in the patient sample (increased homozygosity). We observed a significant decrease in the frequency of 12 heterozygotes in subjects with cocaine dependence (29.8%) vs controls (46.9%) (P </= 0.028). This percentage was still lower in those who had chronically used cocaine for more than 10 years (25%), or more than 15 years (21.5%). The DRD3 gene accounted for 1.64% of the variance of cocaine dependence. The DRD2 gene had an independent and additive effect on cocaine dependence. These findings support a modest role of the DRD3 gene in susceptibility to cocaine dependence.

Adult↗

PubMed1998

Correlation of length of VNTR alleles at the X-linked MAOA gene and phenotypic effect in Tourette syndrome and drug abuse.

Abnormalities in monoamine oxidase (MAO) levels have been implicated in a wide range of psychiatric disorders. We have examined a VNTR polymorphism at the X-linked MAOA gene to test two hypotheses: (1) Do variants of the MAOA gene play a role in any of the behavioral disorders associated with Tourette syndrome or drug abuse? (2) If so, is there any correlation between the length of the alleles and the phenotypic effect? We examined two independent groups: 375 TS patients, relatives and controls, and 280 substance abusers and controls. The alleles were divided into four groups of increasing size. There was a significant association between the MAOA gene and behavioral phenotypes in both groups, and in both the longest alleles were associated with the greatest phenotypic effect. The strongest effect was for the diagnosis of drug dependence (P=0.00003). The VNTR allele groups were in significant linkage disequilibrium with the Fnu4H1 polymorphism previously shown to be associated with MAO-A activity. While these results are consistent with the possibility that different-sized alleles of the short-repeat polymorphisms themselves may play a role in gene regulation, further studies directly linking these alleles with enzyme levels need to be done.

Alleles↗

PubMed1997

Association between the cannabinoid receptor gene (CNR1) and the P300 event-related potential.

In our prior study we observed a significant association between homozygosity for the > or = alleles of a microsatellite polymorphism of cannabinoid receptor genes (CNR1) and drug dependence. Decreased amplitude of the P300 wave of evoked related potentials (ERP) has long been shown to be associated with alcohol and drug dependence. The P300 wave reflects attentional resource allocation and active working memory. Since marijuana intoxication has a potent blocking effect on short-term memory we examined the association between the CNR1 alleles and the P300 wave amplitude at three electrodes in 35 alcohol and drug addicts, by MANOVA. There was a significant decrease in amplitude of the P300 wave for all three electrodes (P = 0.028) that was most marked for the frontal lobes (P = 0.008) in subjects homozygous for the CNR1 > or = 5 repeat alleles. Multivariate regression analysis indicated the CNR1 gene contributed to 20% of the variance of the frontal lobe P300 wave amplitude.

Alcoholism↗

PubMed1997

Cannabinoid receptor gene (CNR1): association with i.v. drug use.

The receptors for tetrahydrocannabinol, the active ingredient of marijuana, have been identified. A microsatellite polymorphism (AAT)n at the cannabinoid CB1 (brain) receptor gene (CNR1) consists of 9 alleles. Since the cannabinoid system is part of the reward pathway we examined the hypothesis that genetic variants of the CNR1 gene might be associated with susceptibility to alcohol or drug dependence. The study consisted of 92 subjects on an Addiction Treatment Unit (ATU) and 114 controls. All were non-Hispanic Caucasians. The ATU subjects were screened for all types of substance dependence using the Diagnostic Interview Schedule (DIS), and for a variety of substance abuse symptoms using the Addiction Severity Index (ASI). Since inspection of the distribution of alleles in controls vs i.v. drug use showed a decrease in the frequency of the 4 allele, and the < 4 alleles were rare, the alleles were divided into two groups, < 5 and < or = 5, and three genotypes < 5/< 5, heterozygotes, and > or =/> or = 5. When all variables were subjected to factor analysis, factor 1 showed a clustering of drug dependence variables and factor 2 of alcohol dependence variables. By ANOVA only factor 1 showed significant differences by genotype consistent with a model where homozygosity for the > or = 5 repeat alleles showed the greatest effect. The number of i.v. drugs used was significantly greater for those carrying the > or =/> or = 5 genotype than for other genotypes (P = 0.005). The association with specific types of drug dependence was greatest for cocaine, amphetamine, and cannabis dependence. The results are consistent with a role of cannabinoid receptors in the modulation of dopamine and cannabinoid reward pathways. Independent studies should be designed to further confirm the hypothesis that cannabinoid receptors may contribute to the susceptibility to drug abuse.

Administration, Inhalation↗

PubMed1995

Protective effect of beta-blockade on dipyridamole-induced myocardial ischaemia. Role of heart rate.

This study was designed to investigate the effect of heart rate changes on dipyridamole echocardiographic tests in patients with coronary artery disease treated with propranolol. We prospectively studied 12 patients (8 men and 4 women; mean age 56.5 +/- 8.7 years) selected by: (a) angiographic evidence of significant coronary artery disease; (b) adequate echocardiographic window; (c) positive dipyridamole echocardiography test results in baseline conditions (step I); (d) test reproducibility in the absence of treatment; (e) negative dipyridamole echocardiography test results after 7 days of treatment with propranolol (120 mg.day-1) in twice divided doses daily (step II). In all patients treated with propranolol, dipyridamole echocardiographic testing was repeated 24 h after the last negative test. In these patients, transoesophageal atrial pacing was performed at peak dipyridamole infusion to increase heart rate to values similar to those observed at baseline (step III). At baseline, heart rate and rate-pressure product were significantly lower in patients treated with propranolol (-20.3% and -22.5% in group II, P < 0.001 vs step I; -24.3% and -26.4% in group III, P < 0.05 vs step I), but the different treatments did not produce significant differences in systolic and diastolic blood pressure. At peak dipyridamole infusion, heart rate and rate-pressure product increased with either placebo or propranolol treatments with respect to baseline, while remaining significantly lower with propranolol as compared to placebo (-29.6% and -29.5% in step II, P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Antagonists↗

PubMed1995

Asthma and bronchial reactivity: a contribution from multivariate analysis.

This study was performed on 508 young male candidates on the military pilot course of the Air Force Academy. Observations of the following parameters were made: immunoglobulin E (IgE) level, skin sensitivity test (prick test) to most common continuous and seasonal allergens, and results of nonspecific bronchial provocation tests with methacholine. The analysis strategy that has been developed consists of two techniques, "multiple correspondence analysis (MCA)" and "automatic classification". The correlation between the categories of the characters evaluated are: degree of high skin reactivity in relation to high IgE levels, hyperreactivity to low methacholine dose (noticed mainly in subjects allergic to continuous antigens), low degree of skin reactivity (both to continuous and seasonal antigens and found in relation to a low methacholine dose) and medium and low IgE levels. The cluster analysis defined three different classes of subjects: 1) 51.97% of the total observed subjects. 68.82% of those subjects that showed IgE levels above 7300 and a high reactivity to low methacholine dose; 2) 15.94% of subjects with a severe allergy to pollens; and 3) 32.09% of subjects with IgE levels lower than 900, low bronchial reactivity and no allergic component for either seasonal or continuous antigens. The use of multivariate statistical techniques in this field of pathophysiology has allowed a confirmative-explorative study of allergic phenomena in relation to several characters, and the determination of classes of subjects characterized by well-defined categories.

Adolescent↗

PubMed1994

Improved Doppler signal intensity in coronary arteries after intravenous peripheral injection of a lung-crossing contrast agent (SHU 508A)

OBJECTIVES: We tested the hypothesis that SHU 508A, a new lung-crossing contrast agent capable of increasing the Doppler signal to noise ratio in the right heart as well as left heart cavities after intravenous injection, could increase Doppler signal intensity in coronary arteries, thus improving the feasibility and quality of transesophageal Doppler echocardiographic evaluation of coronary blood flow velocity. BACKGROUND: Coronary blood flow velocity can be evaluated by transesophageal Doppler echocardiography. However, an adequate Doppler tracing is obtainable in a relatively low percent of patients. METHODS: Transesophageal Doppler echocardiography of coronary arteries was performed in 35 patients before and after SHU 508A injection at four different dosages (200 mg/ml in 5 ml, 200 mg/ml in 10 ml, 300 mg/ml in 5 ml and 300 mg/ml in 10 ml). Color Doppler mapping of coronary flow and pulsed wave Doppler measurement of coronary blood flow velocity were attempted in all patients. RESULTS: Color Doppler flow mapping of 105 evaluated coronary segments (left main, left anterior descending and circumflex in 35 patients) was not detectable or was weak in 88% of patients before and 33% of patients after echo contrast injection (p < 0.0001); it was optimal (that is, well delineated with complete flow mapping of the explored vessel) in only 11% of patients before and 67% after echo contrast injection (p < 0.0001). In addition, pulsed wave Doppler signal quality improved after echo contrast injection: Pulsed wave Doppler recording of coronary blood flow velocity was not obtainable or was weak in 78% of cases before and 34% after echo contrast injection (p < 0.0001); pulsed wave Doppler recording of coronary blood flow velocity was optimal (that is, there was a complete and well defined outline of diastolic coronary blood flow velocity in 23% of cases before and 66% after echo contrast injection [p < 0.0001]. Both length and width of color Doppler mapping in the left anterior descending coronary artery increased after SHU 508A injection (from 5.75 +/- 5.32 and 1.51 +/- 1.17 to 17.04 +/- 8.76 and 4.21 +/- 1.78 mm, respectively, mean +/- SD, p < 0.0001). CONCLUSIONS: The feasibility and quality of recording coronary blood flow velocity by transesophageal Doppler echocardiography are considerably improved by intravenous injection of SHU 508A. The improved feasibility of this new semi-invasive method for evaluating coronary blood flow velocity and flow reserve can considerably increase its research and clinical utilization.

Aged↗

PubMed1994

Local specific immunotherapy in allergic conjunctivitis.

We evaluated the effect of local specific immunotherapy in 40 patients suffering from seasonal allergic conjunctivitis. Twenty patients received saline solution in both eyes; and 20 others received local specific immunotherapy in both eyes. Sodium cromoglycate drops were instilled in both eyes in all patients. Subjective and objective symptoms, and cytological findings had significantly improved after 1 year in the group treated with local specific immunotherapy plus sodium cromoglycate compared to the group treated with sodium cromoglycate and saline solution.

Adolescent↗

PubMed1993

Case report 784: Fibrous dysplasia of the second pedal digit.

In summary, we have reported on an unusual form of fibrous dysplasia, presumptively monostotic, localized to the middle phalanx of the second pedal digit, and presenting as a mass. Monostotic fibrous dysplasia of phalanges of the foot is rare, but should be considered in the differential diagnosis of a mass in the foot.

Female↗

PubMed1992

Acute thrombosis of prosthetic valves: a multivariate analysis of the risk factors for a lifethreatening event.

In 3231 prosthetic valves implanted between January 1975 and November 1990, we observed 61 cases of prosthetic obstruction of biological origin with clinical and laboratory findings of severe functional impairment which required surgery as emergency treatment. The hospital mortality was 19.67% (12/61). The obstruction was due to a primary thrombosis in all 5 bioprostheses which were not anticoagulated and in 11/56 (19.64%) mechanical prostheses of which 3 were not anticoagulated and 4 were not properly anticoagulated. The obstruction was due to fibrous tissue overgrowth in the other 45 mechanical prostheses (80.35%) with secondary thrombosis in 34 cases (60.71%) and no thrombosis in 11 (19.64%); 71.11% of these prostheses were adequately anticoagulated. Of the 61 obstructed prostheses, 53 were mitral and 8 were aortic. No tricuspid obstruction was observed. A statistical assessment by multiple correspondence, cluster and chi square analysis was performed in two groups of patients with different models of mechanical mitral prostheses. The 5-year actuarial incidence of obstruction was 6.08%. Significant risk factors were: tilting disc prostheses, prostheses without pyrocarbon coating, large prostheses, tilting disc prostheses with a small orifice posteriorly oriented, atrial fibrillation, enlarged left atrium, time from implant greater than 4 years, age between 40 and 50 years. In our opinion, prosthetic obstruction may be referred to a primary thrombosis only in cases where it may be prevented by adequate anticoagulation. In most cases, the obstruction is produced by periprosthetic fibroblastic proliferation which may develop in spite of adequate anticoagulation in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

PubMedDate not supplied

Effect of oral captopril (SQ 14225) on intraocular pressure in man.

The effects of the angiotensin converting enzyme (ACE) inhibitor captopril (SQ 14225) on intraocular pressure (IOP) were studied. Four groups were analyzed: group A, ten control subjects; group B, ten hypertensive patients with normal IOP; group C, ten normotensive patients with primary open angle glaucoma (POAG); and group D, ten hypertensive patients with POAG. Systolic and diastolic blood pressure, heart rate, pupil diameter, IOP and total outflow facility were recorded at baseline and at 1-h intervals up to 3h after an oral dose of 25 mg captopril or placebo, given in a randomized, double-blind cross-over fashion. The alternative treatment was given a week later. Captopril significantly lowered IOP in all patients, with no effects on heart rate and pupil diameter. Blood pressure changed only in patients with hypertension (groups B and D). Total outflow facility, measured by conventional tonography, increased significantly in all groups. These findings indicate that oral captopril could represent a new antiglaucomatous compound.

Administration, Oral↗