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Biomedical subjects

R Costa

Publications and source records attributed to R Costa.

At least 109 records · Page 6Linked to original sources
PubMed1994

[Isradipine versus diltiazem in the treatment of stable effort angina pectoris: ergometric evaluation in a crossover double-blind study].

OBJECTIVES: To evaluate the effects of isradipine (ISR) and diltiazem (DIL) on exercise tolerance and ischemic ST depression in patients with stable effort angina. METHODS: Fourteen out-patients, 9 males and 5 females, aged 46-65 years (mean +/- SD = 57 +/- 8), with ischemic heart disease and reproducible ST-segment depression on two consecutive exercise stress tests in baseline conditions, underwent a study consisting of 4 periods: 1 and 3 placebo, 2 and 4 at random ISR (5 mg b.i.d.) and DIL (120 mg b.i.d.). At the end of each period a multistage treadmill exercise stress test (Bruce protocol) was performed. RESULTS: Both drugs significantly (p < 0.001) increased ischemia time (IT) (0.1 mV ST depression) as compared to placebo, from 438 +/- 132 s. to 620 +/- 164 s. (ISR) and 583 +/- 147 s. (DIL) without statistical difference between two drugs (p = 0.2), and significantly reduced (p < 0.002) the maximal ST depression, from -0.20 +/- 0.11 mV to -0.07 +/- 0.07 mV (ISR) and -0.09 +/- 0.11 mV (DIL). At the IT, systolic blood pressure increased (p = 0.02), from 180 +/- 19 mm Hg to 187 +/- 15 mm Hg (ISR) and 191 +/- 15 mm Hg (DIL); similarly, heart rate increased from 133 +/- 24 bpm to 144 +/- 18 bpm (ISR: p = 0.002) and 140 +/- 17 bpm (DIL: p = NS). CONCLUSIONS: ISR and DIL, at the above dosage have showed an important and significant anti-ischemic effect (IT = +41.5% during ISR and +33.1% during DIL).

Aged↗
PubMed1993

[Biliary surgery and cholescintigraphy with iminodiacetic acid (IDA) analogs. An evaluation of the results and the complications].

Hepatobiliary scintigraphy with analogs of iminodiacetic acid (IDA) has become one of the primary tools in the diagnosis of biliary tract diseases, especially in the evaluation of surgical results and detection of complications that may arise from biliary operative procedures. We have performed cholescintigraphy in 19 patients. Of them, 9 underwent choledochojejunostomy with Roux-en-Y reconstruction for recurrent choledocholithiasis, 1 underwent right hepatic resection for metastasis extirpation, 8 were post cholecystectomy patients effected with upper abdominal pain located either in the epigastric region or right upper quadrant referable to post cholecystectomy syndrome and the last exhibited chronic pancreatitis ans suspicious sphincter of Oddi stenosis. The scintigraphy data were compared with the information yielded by sonography, intravenous cholangiogram (IVC) and, when possible, by endoscopic retrograde cholangiopancreatography (ERCP). Scans were considered pathologic when one or more of the following criteria were present: a) delayed biliary to bowel transit (greater than 1 hr), b) abnormal time-activity dynamic, c) no intestinal activity (obstruction), d) apparent ductal dilatation. In the group of biliary-enteric anastomosed patients, cholescintigraphic findings have shown 3 normal cases, 3 cases of biliary-intestinal obstruction confirmed by surgery, and 3 with abnormal activity retention in the jejunum loop due, in 2 patients, to hypokinesia since the quick emptying following the administration of 10 mg i.v. of metoclopramide, while in the other one, the surgery reexploration exhibited the presence of adhesions producing intestinal stricture. in the last patient of this group, the cholescintigraphy was performed to detect possible biliary leaks. In the post cholecystectomy patients, the cholescintigraphy exhibited in 3 cases dilated common duct with functional patency since the normal biliary-bowel transit time (less than 1 hr); this was confirmed by sonogram and IVC.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1993

Effects of amlodipine on renal haemodynamics in mild to moderate hypertensive patients. A randomized controlled study versus placebo.

In this study the efficacy and safety of short-term amlodipine administration on renal haemodynamics were evaluated in mild to moderate hypertensive subjects. Our final goal was to evaluate whether the reduced blood pressure induced by treatment was associated with maintenance of renal function. After a run-in period with placebo, 30 hypertensive patients without cardiac or renal diseases were randomly allocated to a double-blind 4 weeks controlled study with amlodipine 10 mg once a day (15 patients) or placebo (15 patients). Renal haemodynamic measurements included effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) by radionuclide study using 131I-hippuran and 99mTc, with methods described by Schlegel and Gates, respectively. In addition, effective renal blood flow [ERBF = ERPF/(1-Ht)], filtration fraction (FF = GFR/ERPF) and renal vascular resistance (RVR = MBP x 80/ERBF) were calculated. Plasma renin activity (PRA), serum aldosterone (ALD) and urinary excretion of sodium (NaU) were evaluated. At the end of amlodipine administration a significant decrease (P < 0.001) in SBP, DBP and MBP from baseline values was observed. A significant decrease (P < 0.01) in RVR and significant increases (P < 0.05) in ERPF, ERBF and in NaU were also found, without relevant changes in GFR, FF, PRA and ALD. No significant variation in clinical and renal measurements was observed in the placebo group. No relevant side effects were observed in either group. In conclusion, amlodipine was effective in lowering blood pressure in mild to moderate hypertension and exerted favourable effects on renal haemodynamics and function.

Adult↗
PubMed1993

Fractured rib with penetrating cardiopulmonary injury.

Described is an unusual injury, arising from a motorized vehicle accident, in which a detached fractured rib from a flail chest caused lung perforation and hemopericardium. The full diagnosis was only appreciated on computed tomography. Therefore, thoracotomy averted potential disaster.

Adult↗
PubMed1993

Molecular evolution of a repetitive region within the per gene of Drosophila.

The clock gene period (per) controls a number of biological rhythms in Drosophila. In D. melanogaster, per has a repetitive region that encodes a number of alternating threonine-glycine residues. We sequenced and compared this region from several different Drosophila species belonging to various groups within the Drosophila and Sophophora subgenera. This part of per shows a great variability in both DNA sequence and length. Furthermore, analysis of the data suggests that changes in the length of this variable region might be associated with amino acid replacements in the more conserved flanking sequences.

Amino Acid Sequence↗
PubMed1993

[Anxiety and the mechanisms of action of anxiolytics].

Anxiety disorders are widely present in general population. Epidemiology studies evaluated a 5-10% prevalence of these disorders, whose social impact needs an early diagnosis and an adequate treatment. In recent years, behavioural, neurochemical and pharmacological researches allowed the characterization of several types of pathological anxiety and a new consideration of nosography in order to establish a correct treatment. In particular, a remarkable progress of the knowledge of biological bases of anxiety resulted from study of anxiety animal models and of mechanisms of action of anxiolytic drugs. On this regard mechanism involving GABAergic, serotoninergic and cholecystokininergic were suggestive.

Animals↗
PubMed1993

[An ergometric cross-over evaluation of the anti-ischemic efficacy of amlodipine and gallopamil in stable angina of effort].

In the setting of stable effort angina a single-blind, randomized, cross-over study to evaluate the effects of gallopamil (GAL) and amlodipine (AML) on exercise tolerance and ischemic ST depression was conducted. Fifteen outpatients, 12 males and 3 females, aged 40-65 years (57 +/- 9), with documented coronary atherosclerosis and reproducible ST-segment depression on 2 consecutive baseline exercise stress tests, completed the study, which consisted of 4 periods: 1 and 3 placebo, 2 and 4 at random GAL (50 mg tid) and AML (10 mg/daily). At the end of each period a multistage treadmill exercise stress test (Bruce protocol) was performed. Both drugs significantly (p = 0.0001) increased the ischemia time (IT) (0.1 mV ST depression) as compared to placebo, from 416 +/- 165 s to 635 +/- 161 s (GAL) and 607 +/- 152 s (AML) with significant difference (p = 0.2) between the 2 drugs, and reduced significantly (p = 0.001) the maximal ST depression from -0.25 +/- 0.09 mV to -0.11 +/- 0.08 mV (GAL) and -0.12 +/- 0.09 mV (AML). At the IT, the systolic blood pressure increased from 178 +/- 23 mmHg to 185 +/- 20 mmHg (GAL) and remained unchanged during AML treatment (178 +/- 15 mmHg); similarly, the heart rate increased from 126 +/- 22 b/min to 139 +/- 21 b/min (GAL) and 138 +/- 19 b/min (AML). In conclusion, both GAL and AML showed a good anti-ischemic effect (IT = +52.6% during GAL and +45.9% during AML), even if GAL proved to be significantly more effective than AML.

Adult↗
PubMed1993

[Alcoholism. Aspects of its pharmacology, clinical picture and therapy].

In every age and culture, people have had to distinguish between positive and negative consequences of the use of psychoactive substances. Since the ancient times it was known that alcohol, easily available in wide quantities, could facilitate social contacts. The abuse and the addiction represent, on the other hand, a complicated social phenomenon and are the expression of physiological adaptive mechanisms brought to the extreme point. The high level of diffusion and the complexity of these problems made it necessary to create diagnostic classifications to classify illnesses on the basis of definite and reliable principles, with the main goal of obtaining therapeutic progress. The consequences of alcohol abuse are both physical and psychic, thus therapeutic approaches must take into account these two points. Some pharmacological agents may lead to cross-tolerance with alcohol and, besides, they are not necessary in case of a slight abstinence where brief psychotherapies are sufficient. Recent advances in the knowledge of the mechanisms which underlie alcohol addition suggest approaches particularly aimed to correct imbalances of neurotransmitters that can determine addiction. Among these, GHB acid seems to be particularly important. At the end, on the basis of the latest progress in psycho-immunopharmacology, the relationships between alcohol and disease are considered.

Alcoholic Intoxication↗
PubMed1992

A latitudinal cline in a Drosophila clock gene.

The clock gene period determines biological rhythmicity in Drosophila melanogaster and encodes a protein characterized by an alternating series of threonine-glycine pairs. The minisatellite region encoding the threonine-glycine repeat is polymorphic in length in natural Drosophila melanogaster populations. In this paper we report the geographical analysis of this polymorphism within Europe and North Africa. A robust clinal pattern is observed along a north-south axis. We suggest the possibility that the length polymorphism could be maintained by thermal selection because the threonine-glycine region has been shown to provide thermostability to the circadian phenotype.

Africa, Northern↗
PubMed1992

Effects of oxiracetam on neurotransmitter release from rat hippocampus slices and synaptosomes.

The effects of the nootropic drug oxiracetam on the K(+)-evoked overflow of [3H]D-aspartic acid ([3H]D-ASP), [3H]acetylcholine ([3H]ACh), [3H] gamma-aminobutyric acid ([3H]GABA), [3H]noradrenaline ([3H]NA) and [3H]5-hydroxytryptamine ([3H]5-HT) have been studied in superfused rat hippocampal slices. The overflow of [3H]D-ASP was enhanced by low concentrations of oxiracetam (0.01-1 microM) but not by high concentrations (10-100 microM) which showed some tendency to inhibit it. Similarly, low concentrations of oxiracetam increased, although less effectively, the depolarization-evoked overflow of [3H]ACh, whereas higher concentrations were without effect. At the concentrations active on [3H]D-ASP and [3H]ACh overflow oxiracetam did not affect that of [3H]GABA, [3H]NA or [3H]5-HT. The oxiracetam effects present in slices could not be observed in hippocampal synaptosomes. Thus oxiracetam may selectively increase the release of glutamate and acetylcholine in hippocampus by a mechanism which appears not to be sited in the releasing nerve terminals.

Acetylcholine↗
PubMed1992

Evolution of the threonine-glycine repeat region of the period gene in the melanogaster species subgroup of Drosophila.

The Threonine-Glycine (Thr-Gly) region of the period gene (per) in Drosophila was compared in the eight species of the D. melanogaster subgroup. This region can be divided into a diverged variable-length segment which is flanked by more conserved sequences. The number of amino acids encoded in the variable-length region ranges from 40 in D. teissieri to 69 in D. mauritiana. This is similar to the range found within natural populations of D. melanogaster. It was possible to derive a Thr-Gly "allele" of one species from that of another by invoking hypothetical Thr-Gly intermediates. A phylogeny based on the more conserved flanking sequences was produced. The results highlighted some of the problems which are encountered when highly polymorphic genes are used to infer phylogenies of closely related species.

Amino Acid Sequence↗
PubMed1992

Electrophysiologic effects of magnesium sulfate infusion in patients with cardiac conduction defects.

We report the electrocardiographic and electrophysiologic effects of magnesium (Mg) sulfate infusion in 25 normomagnesemic patients (16 men and 9 women, aged 22-74 years; mean +/- SD, 60.4 +/- 11.9) with different cardiac conduction impairments. Ten patients had chronic ischemic heart disease, two had idiopathic dilated cardiomyopathy, two had hypertensive heart disease, three had valvular heart disease, five had sclerodegenerative heart disease and three had no clinical evidence of cardiac disease. Five patients had trifascicular block [first degree atrioventricular (A-V) block+right bundle branch block (RBBB)+left anterior hemiblock (LAH)], eight had bifascicular block (6 RBBB+LAH, 2 first degree A-V block+RBBB), four had isolated first degree A-V block and eight had bundle branch block [5 RBBB, 3 left bundle branch block (LBBB)]. Before and during Mg infusion (50 mg/min/60 min) we evaluated the A-V (P-R), intraatrial (P-A), suprahisian (A-H), infrahisian (H-V) conduction times, electrical ventricular systole (Q-T), Q-T index (Q-Tc) intraventricular conduction time (QRS) and heart rate. At the end of infusion the P-R, P-A, A-H, H-V increased from 215.4 +/- 36.6, 33.6 +/- 9.1, 112.8 +/- 37.3, 69.0 +/- 12.8 ms to 217.6 +/- 37.1 (p less than 0.002), 33.8 +/- 9.4 (NS), 114.2 +/- 38.1 (p less than 0.005), 69.6 +/- 13.3 (NS) ms. QRS complex did not change (125 +/- 16.9 ms).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Widespread dermatophytosis due to Microsporum (Trichophyton) gallinae in a patient with AIDS--a case report from Spain.

We report the case of a 25-year-old, HIV-positive patient (group IV, A, C2 clinical stage) with a widespread dermatophyte infection. He was a male gypsy with a known history of intravenous drug abuse. After an episode of cerebral toxoplasmosis for which he was treated with systemic steroids (because of cerebral oedema) he developed, over 16 days, a remarkably extensive ringworm of the trunk due to an unusual zoophilic dermatophyte, Microsporum (Trichophyton) gallinae. Human infection with this dermatophyte species is unusual: there are as few as seven proven reported cases, all of whom had localized lesions. This is the first widespread and severe case reported in man and also the first reported from Spain.

AIDS-Related Opportunistic Infections↗
PubMed1992

Combination therapy for NIDDM with biosynthetic human insulin and glyburide.

OBJECTIVE: TO investigate the effects of the addition of glyburide to the regimen of insulin-treated non-insulin-dependent diabetes mellitus (NIDDM) patients with regard to their overall insulin requirement and dosage schedule and to assess persistence of these effects. RESEARCH DESIGN AND METHODS: A double-blind randomized parallel-groupo, placebo-controlled, 20-wk outpatient trial at the Clinical Research Unit (CRU) at St. Luke's/Roosevelt Hospital (New York). Subjects were 20 insulin-dependent NIDDM patients previously managed on insulin alone. After a baseline period of satisfactory diabetes control on biosynthetic human insulin alone, insulin dosage was halved, and patients were placed on a combination with either glyburide or placebo. Diabetes control equivalent to baseline was reestablished by adjusting insulin as required on subsequent visits to the CRU. RESULTS: Insulin requirements in the glyburide group decreased by 29 U at 14 wk compared with 9 U in the placebo group (P less than 0.05). At 20 wk, the decreases remained significant (25 vs. 11 U, respectively; P less than 0.05). The mean +/- SD reduction in insulin requirement in the glyburide group was relatively constant (25 +/- 10 U) and was not related to premedication insulin requirement. Successful response to glyburide was inversely correlated with initial serum alkaline phosphatase level. CONCLUSIONS: Glyburide reduces insulin requirements for 20 wk of combination therapy in NIDDM patients. Patients whose initial insulin requirement is less than or equal to 25 U have a 50% chance of achieving equivalent glycemic control on glyburide alone.

Aged↗
PubMed1992

[Update on benzodiazepines].

The Authors shortly review the benzodiazepine (BDZ) pharmacology and therapeutic. They start from the supposed mechanism of action, then the main indications, counterindications and side effects are reported. Finally, the pharmacokinetic and general classification of the drugs are examined.

Adult↗