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C Andrade

Publications and source records attributed to C Andrade.

At least 19 recordsLinked to original sources
PubMed1995

Effect of felodipine on cholinergic responses of the colonic smooth muscle of streptozotocin induced diabetic rats.

In streptozotocin induced diabetic rats, irrespective of felodipine treatment (5 mg/kg/day po for 4 weeks), a reduction in contractile response of colonic smooth muscle in vitro was observed. Similarly, in both control and diabetic rats treated with felodipine, contractile response was reduced. However, in felodipine treated diabetic rats there was a significant increase in response to exogenous acetylcholine. It may be of interest to study the effect of felodipine, on gastro-intestinal motility in vivo in diabetic rats, to enable extrapolation of the present results to the effect of felodipine on gastrointestinal complications of diabetes mellitus.

Acetylcholine↗
PubMed1994

BR-16A protects against ECS-induced anterograde amnesia.

BR-16A is an herbal (non allopathic) medication used in India to enhance cognition. In experiment 1, 28 Wistar rats received either BR-16A (200 mg/kg/day) or vehicle alone for 3 weeks. During the third week, the rats were tested for learning in the Hebb Williams complex maze. BR-16A-treated rats showed significantly better learning than did controls. Experiment 2 was conducted identically except that during the second week all of 32 rats additionally received six once-daily electroconvulsive shocks (ECS). An advantage for learning was again demonstrated for the BR-16A group. It is concluded that BR-16A facilitates learning, and that this effect extends to a protection against ECS-induced anterograde amnesia. Cognitive deficits induced by electroconvulsive therapy are a major disadvantage of the treatment and, to-date, no drug has been found to offer satisfactory protection against such deficits. It is suggested that BR-16A may hold promise in the containment of electroconvulsive therapy (ECT)-induced cognitive compromise.

Amnesia↗
PubMed1994

Effect of felodipine on myocardial function and cholinergic responses in short term streptozotocin diabetes in rats.

Cardiovascular complications of diabetes mellitus account for 80% of deaths among diabetics. Autonomic neuropathy increases the susceptibility of the diabetic myocardium to arrhythmias. Decreased contractility of diabetic myocardium is associated with intracellular calcium overload. However, the relationship between calcium levels and myocardial cholinergic responses is not known. This study was undertaken to observe the effect of felodipine 5 mg/kg on myocardial function and cholinergic responses of the spontaneously working isolated heart of rats with short term streptozotocin-diabetes. Felodipine was administered (po) for 4 week to rats with streptozotocin-diabetes of 4 week duration. Felodipine did not alter the blood glucose levels. The increased cardio-somatic ratio in diabetic rats was attenuated by felodipine. Diabetic status was associated with decreased coronary flow and felodipine increased coronary flow in diabetic rat hearts both before and after ACh. It may be concluded that felodipine favourably altered the adverse myocardial pathology in experimental diabetes, and this strengthens its use as an antihypertensive in diabetics.

Acetylcholine↗
PubMed1994

Correlation of time course of blood cholinesterase activity and toxic manifestations of acute methylparathion in antidote treated rats.

Study was conducted to find out the correlation between red blood cholinesterase (RBC ChE) and plasma butyryl cholinesterase (BuChE) activities and toxic signs of oral methylparathion (MPT) and their recovery pattern with or without atropine treatment in female rats. Enzyme activity was estimated before and after an oral dose of MPT (7.5 mg/kg-1) at various time intervals upto 120 hr. Antidote groups received atropine (10 mg/kg-1, i.p.), either alone or with diazepam (2.5 mg/kg-1, i.p.), at the onset of toxic signs. Inhibition of enzyme activity served as definite index of acute toxicity of MPT. RBC ChE activity correlated with the intensity of toxic signs in no-antidote rats, while in atropine treated groups, there was no correlation. BuChE levels did not correlate with toxic signs in any of the groups except in the fatal group. The resynthesis of both the enzymes was complete in 120 hr study and did not synchronize with the recovery pattern of animals from toxic signs. Compared to BuChE, RBC ChE activity was found to be a more sensitive indicator for the diagnosis of severity of MPT toxicity.

Administration, Oral↗
PubMed1994

Relationship between rate of administration of electroconvulsive shocks and rate of learning in rats: implications for the practice of ECT.

Number of electroconvulsive therapy (ECT) treatments administered and severity of psychopathology confound the interpretation of clinical studies that address the relationship between the rate of administration of ECT and cognitive morbidity occasioned by the treatment. A preclinical study was therefore conducted to address the issue. Three groups (n = 8/group) of adult male Sprague-Dawley rats received six electroconvulsive shocks (ECS) in daily ECS, 3 ECS/week, and 2 ECS/week schedules; a fourth group (control; n = 8) received only sham ECS. From days 2 to 7 after the conclusion of the ECS/sham ECS course, the rats were monitored for learning on the Hebb-Williams complex maze. The control, 2 ECS/week, and 3 ECS/week groups showed significant learning by days 3, 5, and 7, respectively, while the daily ECS group showed no significant learning during the assessment period. This indicates that even when the cumulative effect of ECS on learning is controlled for, more frequent ECS is associated with slower learning. Extrapolating to clinical settings, it is suggested that wider spacing of ECT may lessen ECT-induced cognitive morbidity.

Animals↗
PubMed1994

An exploratory evaluation of ECT in haloperidol-treated DSM-IIIR schizophreniform disorder.

In a double-blind, prospective study, 30 consecutive treatment-naive adult men with first-onset psychosis and DSM-IIIR provisional schizophreniform disorder (without good prognostic features) were randomized into true electroconvulsive therapy (ECT) and sham ECT groups. Both groups received haloperidol in a fixed dose of 15 mg at night. The ECT schedule comprised six bilateral, sinusoidal wave treatments administered on alternate days, thrice a week. Weekly ratings for the first 6 weeks showed an absence of significant difference between the groups in the number of patients responding and in the rate of attenuation of psychosis; severity of depression, while less in the true ECT group after the first 3 weeks, did not differ between the groups at any subsequent time point. Clinical ratings were repeated at 6 months, and social functioning was assessed; again, no group differences emerged. It is concluded that ECT does not meaningfully improve response in unselected schizophreniform disorder that is treated with an adequate dose of neuroleptic.

Adolescent↗
PubMed1994

ECT-induced anterograde amnesia: can the deficits be minimized?

To date, no pharmacological agent has been confirmed to lessen electroconvulsive therapy (ECT)-induced memory deficits. BR-16A is an herbal preparation, containing various organic extracts, used in India for the enhancement of cognition (among other applications). In the present study, adult male Sprague-Dawley rats received six once-daily electroconvulsive shocks (ECSs). Half the animals were treated with BR-16A (200 mg/kg/day) for 1 week before ECS, during the ECS course, and during the post-ECS learning assessment phase; the remaining animals received vehicle alone. In experiment 1, rats (n = 16/treatment group) were preassessed for learning on days 3 and 5 of exposure to the Hebb-Williams complex maze and were reassessed after comparable exposure to the maze starting from the second day post-ECS. In experiment 2, rats (n = 9/treatment group) were preassessed for number of trials to satisfactory learning and number of wrong arm entries in a T-maze and were reassessed on the second day post-ECS. The learning preassessments were conducted just prior to the commencement of the BR-16A/vehicle treatments. In both experiments, rats receiving BR-16A performed significantly better than controls. It is concluded that BR-16A protects against ECS-induced anterograde amnesia. BR-16A may therefore have scope in minimizing ECT-induced learning deficits.

Amnesia, Retrograde↗
PubMed1993

Effects of ECT-dothiepin combination on learning in rats.

Electroconvulsive therapy (ECT) and antidepressant drugs are each known to impair learning and memory. No information is available on their effects on cognition when used concurrently in the treatment of depression, as is frequent in India. In the present study, therefore, the effects of electro-convulsive shocks (ECS) and dothiepin, separately and in combination, were studied in an animal model employing a complex maze operant learning paradigm. ECS were given on alternate days (3/week) for 2 weeks. Dothiepin (10 mg/kg, ip) was administered once daily for 2 weeks. Learning was assessed on days 2-10 post-treatment ECS produced greater initial impairment in learning while dothiepin produced a more sustained impairment. While impairment was maximum in the combined treatment group, the statistical significances that emerged to proscribed the combination were but weak.

Animals↗
PubMed1992

Delayed effects of acute oral and chronic inhalational exposure to methylparathion on learning and memory in rats.

Impairment of acquisition phase of the learning process was observed in rats even at 3 weeks after single oral exposure to the near-lethal dose of commercial grade methylparathion (MP) followed by atropine resuscitation. Though there was a trend towards memory impairment in this group of animals, memory retention was not significantly affected. Chronic inhalational exposure to MP (one exposure/day for 3 weeks) did not significantly alter learning or memory. No significant alteration in red blood cell or brain acetylcholinesterase levels were observed in either of the two groups. It appears that behavioural effects can persist even 3 weeks after exposure to acute near-lethal doses of the pesticide, as occurs in the clinical situation of suicidal attempts; while repeated exposure to no-observed-effect-level doses as occurs in farm and factory workers, may not be associated with behavioural changes.

Acetylcholinesterase↗
PubMed1992

Effect of dothiepin on nociceptive response in diabetic rats.

In alloxan-diabetic rats of 4 wk duration with blood glucose levels of about 300 mg/100 ml, the tail flick reaction time (TFRT) to thermal stimuli was significantly elevated (P less than 0.25), indicating hypoalgesia. Intraperitoneal dothiepin, injections of 25 mg & 50 mg/kg body weight per day did not significantly alter the TFRT, either in control or in diabetic rats, following either acute (one dose), or short term (once a day for five days) administration. It is concluded that at least in the dosage schedule used herein, dothiepin does not influence hypoalgesia of diabetic neuropathy.

Analysis of Variance↗
PubMed1991

[Aortocoronary bypass. Intermittent clamping of the aorta versus cardioplegia].

STUDY OBJECTIVE: Cardioplegia is the standard method of myocardial protection during aorto-coronary bypass surgery. However, there are other alternatives which the authors intend to test. DESIGN: Forty consecutive, non-selected cases of coronary artery bypass surgery done with intermittent aortic crossclamping (Group A) are compared with the 40 preceding consecutive cases where cardioplegia was used (Group B). PATIENTS: The mean age of the patients of group A was 57.5 years (range 42-69 years) and that of group B was 57.1 years (range 39-76 years). Patients of group A had an incidence of previous myocardial infarct of 42.5% against 65.0% in group B. Chronic angina led to surgery in 33 cases of group A and in 32 of group B. The remainder (18.8%) had unstable angina. INTERVENTIONS: The mean number of grafts per patient was 2.9 in group A and 3.2 in group B. Internal mammary arteries were used in most patients of both groups, with 61 anastomoses in group A (1.5/patient) and 57 in group B (1.4/patient). The mean ischaemic time per graft was 7.4 min (range 5.5-11 min) in group A and 15.6 min (8.5-22 min) for group B. MAIN RESULTS: Serial analysis of myocardium-specific serum enzymes and the CPK-MB/total CPK ratio has not evidenced perioperative infarction in any patient of either group. Although enzyme levels were slightly higher in group A, the difference has not reached statistical significance. However, the electrocardiograms have shown one perioperative infarct in each group. Vasodilators were generally used in the 2 groups, for a mean of 16.8 hours, while inotropic drugs were required in only 4 cases of group A and 3 of group B. There has been no hospital mortality in either group. CONCLUSIONS: These results, in a series of non selected patients, demonstrate that intermittent crossclamping may be an acceptable alternative method of myocardial protection during aorto-coronary bypass surgery thus made simple, quick and secure.

Adult↗
PubMed1991

[Assessment of the left ventricular function in patients with pacemakers VVI and DDD, using non-invasive methods (systolic time)].

OBJECTIVE: Determination of left ventricular function, in patients with ventricular inhibited (VVI) and atrioventricular universal (DDD) pacemakers, by measurement of systolic time intervals. DESIGN: Twenty six patients were studied (six with DDD pacemakers and twenty with VVI pacemakers). In all of them systolic time intervals measurements were obtained the day before and one week after the implant. PATIENTS: We have studied twenty six patients consecutively, and all of them completed the study. INTERVENTIONS: The measurement of systolic time intervals was obtained, by the simultaneous recording of ECG, phonocardiogram and carotid arterial pulse. The recordings were obtained at a paper speed of 100 mm/sec. MEASUREMENTS AND RESULTS: The values obtained before the implantation were similar in both groups, but one week after implantation they show a closer to normal ventricular function, in patients with DDD pacemakers. CONCLUSIONS: The measurements of systolic time intervals, is a very easy method, to determine left ventricular function non invasively. In patients with DDD pacemakers, the left ventricular function, was better than in patients with VVI pacemakers.

Aged↗
PubMed1990

Polyelectrolyte and rheological studies on the polysaccharide welan.

This paper investigates the polyelectrolyte behaviour of welan in aqueous solution. From conductivity and activity measurements it is demonstrated that a double-helical conformation is adopted irrespective of pH and ionic strength. The intrinsic pK of its carboxylic groups is found to be abnormally low (pKO = 2.2) and no conformational transition was observed during neutralization. The viscometric behaviour was studied as a function of degree of neutralization, polymer concentration, shear rate and ionic strength. The linear relation [eta] = f(Cs-1/2) allows the determination of B, the stiffness parameter from Smidsrød, whose value characterizes a very stiff molecule.

Carbohydrate Conformation↗