Biomedical subjects

M Y Hasan

Publications and source records attributed to M Y Hasan.

30 records · Page 2Linked to original sources

PubMed2000

Alternative medicine and the medical profession: views of medical students and general practitioners.

A survey was undertaken to explore the attitudes and practices of general practitioners and medical students in the United Arab Emirates with regards to forms of therapy not generally accepted by conventional medicine, including herbal medicine, acupuncture, homeopathy, spiritual therapy and osteopathy/chiropractic. The study found that alternative medicine is in common use to complement conventional medicine by a section of educated people within the health care system. Our observations lead us to appreciate its role in community health care and indicate a need to design culturally appropriate medical curricula which incorporate information about alternative medicine.

Adult↗

PubMed1999

Management of neuroleptic malignant syndrome with anticholinergic medication.

Neuroleptic Malignant Syndrome (NMS) is a life-threatening adverse reaction arising from the use of neuroleptic medications. While dopaminergic agonists, dantrolrene and supportive care are traditionally utilized in the stabilization and management of NMS, anticholinergic medication may also prove effective therapy. Treatment with anticholinergic medication has been suggested in cases of NMS associated with mild hyperthermia. We describe a case of 17-y-old female, who was brought to the emergency department for a possible "acute dystonic reaction". The patient received 50 mg diphenhydramine i.v., which resulted in improvement in mental status. The patient was readmitted to the emergency department 1 d following discharge with symptoms similar, but now considering the diagnosis of NMS. Diphenhydramine 50 mg i.v. was again administered and resulted in significant improvement.

Adolescent↗

PubMed1998

The views of senior students and young doctors of their training in a skills laboratory.

The study was carried out in the Faculty of Medicine and Health Sciences (FMHS), United Arab Emirates (UAE) University, UAE, where a skills laboratory was set up in 1988 to train medical students in clinical skills before they use such skills on patients. The students learn clinical skills using simulated patients, models and mannequins. The training starts in the first year of the 6-year undergraduate curriculum and continues until the end of the fourth year, after which students rotate through the clinical specialties. This study sought to identify: (1) the views of senior clerks (sixth year) and interns (first postgraduate year) regarding the clinical skills training in the skills laboratory (SKL) during the early years of the medical curriculum; (2) the differences in views between senior clerks and interns; (3) the differences in views between women and men students. Students' views about communication, interviewing, physical examination, therapeutic, diagnostic and laboratory skills were investigated. The results indicated that prior training in clinical skills was helpful to the senior clerks and the interns. Statistically significant differences in opinion were noted between the senior clerks and the interns, the interns being more positive about the usefulness of the SKL training compared with learning clinical skills directly on patients. There was no difference between men and women students except that women students were not comfortable with allowing their peers to examine any part of their bodies. The findings of the study have direct implications for the SKL programme.

Clinical Clerkship↗

PubMed1994

Cholecystokinin type B receptor antagonist PD-136,450 is a partial secretory agonist in the stomach and a full agonist in the pancreas of the rat.

Gastrin (cholecystokinin type B (CCK-B)) receptor antagonists may help to elucidate the physiological role of gastrin, have therapeutic potential as acid antisecretory drugs, and may be of use as adjuvant therapy for gastrin sensitive tumours. In binding studies, the gastrin receptor antagonist PD-136,450 had at least 1000 fold greater affinity for gastrin (CCK-B) than CCK-A receptors. In this study the biological activity of PD-136,450 was evaluated in conscious and anaesthetised rats. PD-136,450 antagonised gastrin stimulated acid secretion after subcutaneous (IC50: 0.28 mumol/kg; conscious rats) and intravenous (IC50: 0.17 mumol/kg; anaesthetised rats) administration. In basal secreting fistula animals, the compound stimulated acid output to 30 (5)% of the maximal response to gastrin. Stimulant activity was not caused by gastrin release. As an agonist PD-136,450 was about 350 times less potent than gastrin-17 on a molar basis. In addition, PD-136,450 was a powerful agonist of pancreatic secretion in anaesthetised rats. The specific gastrin antagonist L-365,260 inhibited the (partial) agonist activity of PD-136,450 in the stomach and the specific CCK-A receptor antagonist L-364,718 inhibited the agonist activity of PD-136,450 in the pancreas. It is concluded that the agonist effect of PD-136,450 is mediated via interaction with the gastrin (CCK-B) receptor in the stomach and the CCK-A receptor in the pancreas.

Animals↗

PubMed1990

Comparison of the inhibitory action of aminobeclamide and beclamide on socially offensive behaviour.

The inhibitory effects of aminobeclamide (N-(p-aminobenzyl)-beta-chloropropionamide) on socially offensive behaviour has been studied and compared with those of the parent drug beclamide (N-benzyl-beta-chloropropionamide). Following oral administration in mice which had been individually housed for a 28 day period then paired with normal group-housed opponents, aminobeclamide and beclamide both produced significant and dose-related inhibition of socially offensive behaviour. Aminobeclamide (20-150 mg kg-1 p.o.) and beclamide (50-250 mg kg-1 p.o.) gave increased offense onset latency whilst at the same time they reduced the incidence of offense encounters/animal and decreased the group percentage of animals displaying offense behaviour. It is likely that both drugs have similar monoamine modifying effects though this animal study suggests that aminobeclamide is 1.5 to 2.7 times more potent than beclamide against socially offensive behaviour.

Animals↗

PubMedDate not supplied

Weak inhibitors protect cholinesterases from strong inhibitors (paraoxon): in vitro effect of ranitidine.

Metoclopramide (MCP) is a dopamine receptor antagonist and serotonin receptor agonist widely used as an antiemetic and gastric prokinetic drug. In addition MCP is a weak and reversible inhibitor of cholinesterases. We have shown that MCP has a cholinesterase protective effect against inhibition by organophosphates. The putative mode of protective action of MCP is competition for the active site of the enzyme with the more potent organophosphate. In the present paper we present our results using another weak inhibitor of cholinesterases: ranitidine (RAN). The purpose of the study was to quantify in vitro the extent of RAN-conferred protection, using paraoxon (POX) as an inhibitor. Paraoxon is a non-neuropathic organophosphate responsible for a large number of accidental or suicidal exposures. Red blood cell (RBC) acetylcholinesterase (AChE) activities in whole blood and butyrylcholinesterase (BChE) activities in human plasma were measured photometrically in the presence of different POX and RAN concentrations and the IC50 was calculated. Determinations were repeated in the presence of increasing RAN concentrations. The IC50 shift induced by the presence of RAN increases with the RAN concentration in a linear manner. The shift was more pronounced with RBC-AChE. The protective effect of RAN on cholinesterase could be of practical relevance in the treatment of POX poisoning. We conclude that in vivo testing of RAN as an organophosphate protective agent is warranted.

Acetylcholinesterase↗

PubMedDate not supplied

Protective agents in acute high-dose organophosphate exposure: comparison of ranitidine with pralidoxime in rats.

Weak and reversible inhibitors of cholinesterase, when coadministred in excess with a more potent inhibitor such as organophosphates, can act in a protective manner. Ranitidine (RAN) is a clinically widely used histamine type 2 (H2) receptor blocker. Ranitidine is also the most potent inhibitor of acetylcholinesterase among H2 blockers (inhibitory constant K in the low micromolar range) but roughly three orders of magnitude less potent than paraoxon. This study evaluates RAN-conferred protection in acute high-dose organophosphate (paraoxon, POX) exposure in rats in direct comparison with the therapeutic gold-standard pralidoxime (PRX). Group 1 received 1 microM POX, group 2 received 50 microM RAN, group 3 received 50 microM PRX, group 4 received 1 microM POX + 50 microM RAN and group 5 received 1 microM POX + 50 microM PRX. All substances were applied intraperitoneally. The animals were monitored for 48 h and mortality was recorded at 30 min and 1, 2, 3, 4, 24 and 48 h. Blood was taken for red blood cell acetylcholinesterase (RBC-AChE) measurements at baseline, 30 min and 24 and 48 h. Mortality occurred mainly in the fi rst 30 min after POX administration, with minimal changes occurring thereafter. Mortality (in %) at 30 min in groups 1, 4 and 5 was 52 +/- 18, 37 +/- 20 and 17 +/- 18, respectively, and mortality at 48 h was 59 +/- 12, 39 +/- 20 and 28 +/- 20, respectively. The RBC-AChE activities (in % of baseline values) at 30 min in groups 1, 4 and 5 were 18 +/- 16, 47 +/- 23 and 48 +/- 20, respectively. At 24 h the values were 46 +/- 16, 65 +/- 24 and 86 +/- 17, respectively, and at 48 h the values were 71 +/- 19, 78 +/- 21 and 110 +/- 27, respectively. Coadministration of PRX significantly decreases mortality in the described model at all points in time. Coadministration of RAN statistically significantly decreases mortality at 24 and 48 h. The extent of protection conferred by RAN is less (but not statistically significantly so) than that conferred by the gold-standard PRX. Coadministration of PRX statistically significantly increases RBC-AChE activities in the described model at all points in time. Ranitidine confers a statistically significant protection for the enzyme at 30 min only. We conclude that RAN is potentially of clinical use in reducing mortality in acute high-dose organophosphate exposure. Further studies involving different organophosphates and dosages, as well as different animal species, will be needed both to con fi rm these initial findings and to address the issue of the optimal timing for RAN preadministration.

Animals↗

PubMedDate not supplied

Weak inhibitors protect cholinesterases from strong inhibitors (paraoxon): in vitro effect of tiapride.

Weak and reversible inhibitors of cholinesterases, when administered before potent organophosphorus inhibitors (pretreatment), have the ability, to a certain extent, to protect enzymes from inhibition. Such a protective effect was demonstrated in vitro for metoclopramide and ranitidine. The putative mode of protective action of these substances is, when administered in excess, competition for the active site of the enzyme with the more potent organophosphate. The present paper presents results using another benzamide with weak cholinesterase inhibitory properties: tiapride (TIA). The purpose of the study was to quantify in vitro the extent that TIA conferred protection, using paraoxon (POX) as an inhibitor, and to compare the results with existing data obtained using TIA as a protective agent against dichlorvos (DDVP). POX is a highly toxic non-neuropathic organophosphate. While the use of parathion (the inactive prodrug which is metabolically converted to POX) has been restricted in most countries, the organophosphate is still responsible for a large number of accidental or suicidal exposures. DDVP is a moderately toxic, non-neuropathic organophosphate. Red blood cell (RBC) acetylcholinesterase (AChE) activities in whole blood and butyrylcholinesterase (BChE) activities in human plasma were measured photometrically in the presence of different POX and TIA concentrations and the IC(50) was calculated. Determinations were repeated in the presence of increasing TIA concentrations. The IC(50) of POX increases with the TIA concentration in a linear manner. The protective effect of tiapride on cholinesterase could be of practical relevance in the pretreatment of organophosphate poisoning. It is concluded that in vivo testing of TIA as an organophosphate protective agent is warranted.

Acetylcholinesterase↗

PubMedDate not supplied

In vivo metoclopramide protection of cholinesterase from paraoxon inhibition: direct comparison with pralidoxime in subchronic low-dose exposure.

The benzamide compound metoclopramide (MCP) protects against cholinesterase inhibition by paraoxon (POX) both in vitro and in vivo. This study evaluates MCP-conferred protection of enzyme activity head to head against the therapeutic gold standard pralidoxime (PRX). Six groups of rats were used. All substances were applied i.p. daily for 5 days, followed by a 2-day rest. The 7-day cycle was repeated eight times. Group 1 received 100 nM POX, group 2 received 50 micro M MCP, group 3 received 100 nM POX + 50 micro M MCP, group 4 received 50 micro M PRX, group 5 received 100 nM POX + 50 micro M PRX and group 6 received saline. Red blood cell acetylcholinesterase (RBC-AChE) measurements were performed at baseline and on day 5 of each 7-day cycle. The sums of enzyme activities over time (weekly values expressed as % of baseline of 100%) were compared using the Mann-Whitney rank order test. A Bonferroni correction of 4 for multiple comparisons was applied. Paraoxon significantly reduced enzyme activities when compared with saline (Sigma = 535 +/- 25 vs 902 +/- 42). Metoclopramide conferred statistically significant in vivo protection from inhibition of RBC-AChE by POX (Sigma = 640 +/- 58). The extent of protection was significantly less than that conferred by the gold standard PRX (Sigma = 765 +/- 57). Metoclopramide, in addition to being less effective as an RBC-AChE protective agent, also caused a failure to thrive in the POX+MCP-exposed rats, as evidenced by the changes in body weight.

Acetylcholinesterase↗

PubMedDate not supplied

Weak inhibitors protect cholinesterases from stronger inhibitors (dichlorvos): in vitro effect of tiapride.

Metoclopramide is a benzamide dopamine receptor antagonist and serotonine receptor agonist widely used as an antiemetic and gastric prokinetic drug. In addition, metoclopramide is a weak and reversible inhibitor of cholinesterases. The authors have previously shown that metoclopramide has a cholinesterase protective effect against inhibition by organophosphates (OPs). The putative mode of protective action of metoclopramide is, when administered in excess, competion for the active site of the enzyme with the more potent OP. In the present paper the authors present their results using another benzamide with weak cholinesterase inhibitory properties, tiapride (TIA). The purpose of the study was to quantify in vitro the extent of TIA-conferred protection, using dichlorvos (dichlorovinyl dimethyl phosphate; DDVP) as an inhibitor. DDVP is a moderately toxic (LD50 in rats in the milligram range), non-neuropathic OP. The substance is responsible for a large number of accidental or suicidal exposures. Red blood cell (RBC) acetylcholinesterase (AChE) activities in whole blood and butyrylcholinesterase (BChE) activities in human plasma were measured photometrically in the presence of different DDVP and TIA concentrations and IC50 was calculated. Determinations were repeated in the presence of increasing TIA concentrations. The IC50 of DDVP increases with the TIA concentration in a linear manner. The protective effect of TIA on cholinesterase could be of practical relevance in the treatment of OP poisoning. The authors conclude that in vivo testing of TIA as an OP protective agent is warranted.

Acetylcholinesterase↗

PubMedDate not supplied

The impact of vitamin C on diabetes induced alterations at murine neuromuscular junction.

Physiological functions of skeletal muscle are compromised in diabetes. This may involve free radical mechanisms and may be reversed by antioxidants. We have studied effects of vitamin C on twitch tension, resting membrane potential (RMP) and miniature endplate potentials (MEPPs) frequencies in dorsiflexor muscle of diabetic murine. Forty mice were divided randomly into 2 groups (n = 20 each). One group served as control and the other was injected once with streptozotocin (STZ) solution (60 mg/kg, i.p.) to induce diabetes. The animals were then divided further into two subgroups (n = 10 each). Vitamin C (200 mg/kg, i.p.) was administered daily to one control and one diabetic group for three weeks prior to recording day. Experiments were conducted four weeks following diabetes induction. Isometric twitch tension (evoked directly by muscle stimulation and indirectly by nerve stimulation) was measured in urethane anesthetized (2 mg/g, i.p.) mice via a transducer connected to computer system. Utilizing intracellular recording method, resting membrane potential RMP and MEPPs frequencies were also measured. Compared to control, diabetic mice showed reduced twitch tension (4.2 +/- 0.5 g control versus 2.6 +/- 0.2 g diabetic) and demonstrated delayed half time of decay. Diabetic flexor muscle also displayed significant reduction in MEPPs frequencies with no changes in RMP. Vitamin C reversed tension reduction in diabetic mice (from 2.6 +/- 0.2 g to 3.9 +/- 0.3 g), impacted delayed half time of decay and increased MEPPs frequencies. Vitamin C improves diabetes-induced nerve and muscle dysfunction possibly via a free radical scavenging mechanism.

Animals↗

PubMedDate not supplied

Helping managers to manage: work schedules of field-workers in rural Bangladesh.

The Maternal-Child Health/Family Planning (MCH/FP) Extension Project in Bangladesh identifies and examines barriers to implementation of the national MCH/FP program, and determines strategies to overcome them. This study analyzes field-workers' ability to carry out more tasks than they do presently, and how their performance might be improved when additional field-workers are hired. In two experimental subdistricts, researchers observed the work of family welfare assistants (FWAs), the female family planning field-workers, to determine the duration and frequency of their home visits with village women and the content of their exchanges. While many factors influence the FWA's work, researchers found that the preplanned monthly work schedules could be manipulated relatively easily to improve duration and frequency of program contact with village women. With more time available to spend with women, the potential to improve the quality of services is enhanced.

Bangladesh↗