Biomedical subjects

M Tariq

Publications and source records attributed to M Tariq.

At least 55 records · Page 3Linked to original sources

PubMed1997

Gastric anti-ulcer and cytoprotective effect of l-serine in rats.

Effect of l-serine has been studied for its ability to inhibit gastric secretion and to protect the gastric mucosa against stress and chemically induced ulcers. Acid secretion studies were undertaken in pylorus-ligated rats with and without l-serine treatment. Experimental gastric lesions were induced by hypothermic-restraint stress, indomethacin and necrotizing agents including 80% ethanol, 0.2 M sodium hydroxide and 0.6 M hydrochloric acid in rats. The level of nonprotein sulfhydryl compounds and gastric wall mucus were also measured in the glandular stomach of the rats following ethanol-induced gastric lesions. The results of this study demonstrate that l-serine produces a dose-dependent inhibition of gastric acid secretions in rats. Pretreatment with l-serine also attenuated the formation of stress-, indomethacin- and necrotizing agents-induced gastric lesions. The antiulcer activity of l-serine was associated with significant inhibition of ethanol-induced depletion of nonprotein sulfhydryls and gastric wall mucus. In conclusion, this study demonstrates that l-serine possesses significant antiulcer and cytoprotective activity against various experimentally induced gastric lesions. Although the mechanism of action of l-serine requires further evaluation, the experimental observations derived from this study may have future clinical relevance and therefore deserve to be investigated thoroughly.

Animals↗

PubMed1997

Studies on the antisecretory, gastric anti-ulcer and cytoprotective properties of glycine.

Glycine, a neutral amino acid has been studied for its ability to inhibit gastric secretion and to protect the gastric mucosa against chemically and stress-induced ulcers. Acid secretion studies were undertaken in pylorus-ligated rats with and without glycine treatment. Experimental gastric lesions were induced by hypothermic-restraint stress, indomethacin and necrotizing agents including 80% ethanol, 0.2 M sodium hydroxide and 0.6 M hydrochloric acid in rats. The level of nonprotein sulfhydryl compounds and gastric wall mucus were also measured in the glandular stomach of the rats following ethanol-induced gastric lesions. The results of this study demonstrate that glycine dose dependently reduced the gastric secretions in rats. Pretreatment with glycine significantly protected animals against stress-, indomethacin- and necrotizing agents induced gastric lesions. The antiulcer activity of glycine was associated with significant inhibition of ethanol-induced depletion of nonprotein sulfhydryls and gastric wall mucus. In conclusion, this study demonstrates that glycine possesses significant antiulcer and cytoprotective activity. However, further detailed studies are warranted to establish the mechanism(s) of action, and to determine its role in the prophylaxis and treatment of gastric ulcer disease.

Animals↗

PubMed1996

Quinacrine attenuates cyclosporine-induced nephrotoxicity in rats.

The biochemical mechanism underlying cyclosporine (CsA)* induced nephrotoxicity is far from clear. Increased generation of oxygen derived free radicals (ODFR) and enhanced activity of phospholipase A2 (PLA2) have been observed in experimental animals following treatment with CsA. Several recent reports have shown that quinacrine, besides being a potent inhibitor of PLA2, suppresses the generation of ODFR. The present study was designed to investigate the effect of quinacrine on CsA induced nephrotoxicity in rats. Male Wistar rats (weighing 280-300 g) were randomized into eight groups of eight animals each. Group 1 (control) received appropriate vehicles only, whereas the rats in groups 2, 3, 4, and 5 received subcutaneous injection of CsA (17.5 mg/kg dissolved in olive oil) daily for 8 weeks. The animals in groups 3, 4, and 5 were also given intraperitoneal injections of quinacrine in three different doses of 2.5 mg/kg, 5 mg/kg, and 10 mg/kg body weight, respectively, in addition to CsA. The animals in groups 6, 7, and 8 received intraperitoneal injection of quinacrine alone at doses of 2.5 mg/kg, 5 mg/kg, and 10 mg/kg respectively for eight weeks. After 8 weeks, animals were sacrificed under light ether anesthesia and blood and kidney samples were collected for various biochemical and histological studies. The biochemical parameters included blood urea nitrogen (BUN), serum creatinine (Scr), potassium, and sodium. The blood was also analyzed for the level of CsA. The kidney samples were analyzed for malondialdehyde (MDA), glutathione, and vitamin E (VE). Kidney sections were prepared for histopathological studies using hematoxylin-eosin staining. There was an increase in BUN, Scr, and potassium levels and decrease in sodium levels in cyclosporine alone treated group, suggesting a significant nephrotoxicity. Quinacrine treatment significantly protected animals against CsA induced biochemical changes. Our studies on free radical indices showed that quinacrine treatment protected animals against cyclosporine induced increase in MDA and depletion of glutathione and VE. The beneficial effect of quinacrine against CsA induced nephrotoxicity was also confirmed by histological studies.

Animals↗

PubMed1996

Effect of vitamin E and selenium on hypothermic restraint stress and chemically-induced ulcers.

The present study was undertaken to determine the effect of a combination of selenium and vitamin E on stress and chemical-induced gastric ulcers in rats. The gastric mucosal lesions were produced by hypothermic restraint stress, indomethacin, reserpine, and mucosal damaging agents including 80% ethanol, 0.6 M HCl, 25% NaCl, and 0.2 M NaOH. The gastric secretion studies were undertaken using Shay's pylorus ligation model. The results of this study demonstrated that the treatment of rats with selenium or vitamin E significantly reduced the basal gastric acid secretions when given individually; however, the combination of these agents produced a better inhibition of gastric acid secretions as compared to their individual effect. Both selenium and vitamin E were found to protect gastric mucosa against the lesions produced by hypothermic restraint stress and chemicals, but a highly significant protection was observed when they were used concomitantly. Vitamin E alone and with selenium significantly inhibited ethanol-induced depletion of gastric nonprotein sulfhydryl compounds. Our findings also showed that the combination of selenium and vitamin E provided better protection to gastric mucosa against hypothermic restraint-induced gastric wall mucus depletion. This study clearly suggests the feasibility of using selenium and vitamin E concurrently to achieve better gastroprotective effects.

Animals↗

PubMed1996

Spontaneous internal jugular vein thrombosis and recurrent laryngeal nerve palsy: a rare simultaneous presentation of an occult malignant neoplasm.

Internal jugular vein thrombosis is an uncommon potentially life-threatening disorder caused by various conditions. Non-spontaneous internal jugular vein thrombosis is an uncommon condition associated in the pre-antibiotic area with deep-neck infections. Currently iatrogenic trauma to the internal jugular vein from catheterisation and repeated intravenous injections by drug abusers are the leading causes of thrombosis. Spontaneous internal jugular vein thrombosis may occur when there are no apparent pre-disposing mechanical or inflammatory causes although a few of these patients may harbour an occult malignant neoplasm. Hence, careful investigation and follow-up are vital. Thrombosis in Trousseau's syndrome is usually confined to the vascular system of the extremities and the viscera. However, secondary to the paraneoplastic hypercoagulable state, thrombosis can occur in the large veins of the head and neck region. We understand this to be the first case where spontaneous internal jugular vein thrombosis and ipsilateral recurrent laryngeal nerve paralysis were the only initial manifestations of an occult malignancy.

Aged↗

PubMed1996

Outcome predictors of ultrafiltration in patients with refractory congestive heart failure and renal failure.

This study is an attempt to identify predictors of outcome from the use of ultrafiltration (UF) in patients with refractory congestive heart failure (CHF) and renal failure. The authors studied 30 patients in NYHA functional class IV in whom UF was utilized in the management of refractory CHF. Patients were retrospectively divided into two groups according to their outcome. Group A included 12 patients who improved and survived hospital admission, and group B included 18 patients who did not respond and died shortly after UF. Clinical, hemodynamic, and laboratory data before UF were fairly comparable between both groups. Renal function and hemodynamic parameters were compared and analyzed within the same group and between both groups before and after UF. The mean age in group A was sixty-three +/- thirteen years while in group B it was seventy +/- eleven years (P < 0.005). A mean of 9.6 liters of fluid were removed from group A and 3.2 liters from group B (P < 0.001). Group A showed greater reduction in the mean values of right atrial pressure (P < 0.005) and pulmonary capillary wedge pressure (P < 0.05) after UF. Additionally, group A showed a significant decrease in their blood urea nitrogen (P < 0.05) and serum creatinine values (P < 0.05), in contradistinction to group B patients who showed a major increase in those values after UF. There was no significant change in the mean values of cardiac index, systemic vascular resistance, and pulmonary vascular resistance after UF. These findings suggest that younger age groups, greater fluid removal, as well as significant decreases in blood urea nitrogen, serum creatinine, and right atrial and pulmonary wedge pressures after UF, are associated with favorable outcome. Conversely, older age groups, less fluid removal, and rising blood urea nitrogen and serum creatinine levels after UF were associated with poor outcome.

Age Factors↗

PubMed1996

A double-blind, placebo-controlled, crossover, study to evaluate the efficacy of subcutaneous sumatriptan in the treatment of atypical facial pain.

A double-blind, placebo-controlled crossover study was undertaken to assess the efficacy and tolerability of sumatriptan in patients with atypical facial pain. Patients were aged 18-65 years and had at least a 6 months history of atypical facial pain. A total of 19 patients were recruited and assessed for pain scores (total, sensory and affective) by using a short form McGill pain questionnaire preinjection and and at 60 and 120 minutes after subcutaneous injection of sumatriptan (6 mg) or placebo. Safety and tolerability was assessed by recording adverse events during and after the injection. One patient received only one treatment since her pain symptoms resolved after the first treatment. Rest of the patients returned to the clinic 3-6 weeks later and received alternate treatment for atypical facial pain in the same fashion as on the first occasion. Treatment of patients with sumatriptan produced significant relief in sensory, affective and total pain at 120 minutes postinjection (P < .05). Sumatriptan failed to produce a significant reduction in sensory and total pain scores at 60 minutes following treatment, however the result was statistically significant for the affective pain score (P < .05). No death or other serious adverse events were reported. No patient was withdrawn from the study due to an adverse event. However, all the patients treated with sumatriptan experienced one or more adverse events. The most common reported adverse symptoms during the sumatriptan treatment period were injection site reactions, headache, feeling of heaviness, warm or hot sensation and disorders of mouth or tongue. However, most of these side effects were mild and transient. In conclusion, this study points towards some beneficial effect of a single subcutaneous injection of sumatriptan in the treatment of atypical facial pain. However, this data is not sufficient to suggest the clinical utility of subcutaneous sumatriptan (6 mg) for the management of atypical facial pain. Further studies are necessary to test the effects of prolonged subcutaneous and oral multiple dose administration of sumatriptan for the treatment of atypical facial pain.

Adolescent↗

PubMed1995

Hypobaric spinal anaesthesia with bupivacaine (0.1%) gives selective sensory block for ano-rectal surgery.

Twenty adult male patients undergoing anorectal surgery in the jackknife position under spinal anaesthesia were studied for the anaesthetic properties of 5 ml hypobaric 0.1% bupivacaine. The patients were positioned in the prone, jack-knife position with a pillow under the hips and with an operating table break angulation of 30 degrees with head down tilt of 20 degrees. In this position a 25-gauge Quincke spinal needle was inserted intrathecally through L3-4 and 5 ml solution, prepared by mixing 1 ml bupivacaine 0.5% with 4 ml of distilled water with a specific gravity of 1.001 at 20 degrees C, was given over 15-20 sec. Onset time, progression and upper level of sensory blockade evaluated by pin prick, and the extent of motor block (1 = full motor movement at ankle and knee joint, 2 = restricted motor movements, 3 = full motor block, no movements) were measured at one minute intervals for the first five minutes, then every five minutes for 30 min. The number of dermatomes blocked was also noted. The median level of cephalad sensory blockage was of L1, with a range from T10-L3. On average, nine dermatomes were blocked (range 7-12). Motor blockade was not observed in any patient. Changes in heart rate and blood pressure were minimal. The average duration of postoperative analgesia was 339.5 +/- 182.9 min. Post-spinal headache was not observed in any patients. In conclusion, 5 ml intrathecal hypobaric bupivacaine, 0.1%, provided excellent perioperative analgesia without motor blockade and haemodynamic stability in patients undergoing anorectal surgery in jackknife position.

Adolescent↗

PubMed1995

Dipyridamole attenuates the development of iminodipropionitrile-induced dyskinetic abnormalities in rats.

The present investigation was undertaken to study the effect of dipyridamole on experimental dyskinesia in rats. The movement disorders were produced by intraperitoneal administration of iminodipropionitrile (IDPN) in the dose of 100 mg/kg per day for 12 days. Dipyridamole was administered orally, daily 30 min before IDPN in the doses of 0.5 g/kg, 1 g/kg, and 1.5 g/kg bodyweight in three different groups of rats. Twenty-four hours after the last dose of IDPN, animals were observed for neurobehavioral changes including vertical and horizontal head weaving, circling, backwalking, grip strength, and righting reflex. Immediately after behavioral studies brain specimens were collected for analysis of vitamin E, conjugated dienes, and lipid hydroperoxides as indices of oxygen-derived free radical (OFR) production. Our results showed that concurrent use of dipyridamole significantly protected rats against IDPN-induced neurobehavioral changes in a dose-dependent manner. Treatment of rats with dipyridamole inhibited IDPN-induced decrease of vitamin E and increase in conjugated dienes and lipid hydroperoxides in brain. These findings suggest the involvement of OFR in dipyridamole induced protection against the development of IDPN dyskinesia. Further studies are warranted to determine the role of dipyridamole as a prophylactic agent against the drug induced dyskinetic abnormalities.

Animals↗

PubMed1995

Cysteamine attenuates iminodipropionitrile (IDPN) induced dyskinesia in rats.

The present investigation was undertaken to study the effect of cysteamine on experimental dyskinesia in rats. The movement disorders were produced by intraperitoneal administration of iminodipropionitrile (IDPN) in the dose of 100 mg/kg per day for 11 days. Cysteamine was administered (i.p.), daily 30 minutes before IDPN in the doses of 25 mg/kg, 50 mg/kg and 100 mg/kg bodyweight in three different groups of rats. Twenty four hours after the last dose of IDPN, animals were observed for neurobehavioural changes including vertical and horizontal head weaving, circling, backwalking, grip strength and righting reflex. Immediately after behavioural studies brain specimens were collected for analysis of vitamin E and total glutathione levels. The results of behavioural studies showed that co-treatment with cysteamine protected rats against IDPN-induced dyskinesia. Our biochemical studies showed that IDPN produced a depletion of vitamin E in cerebrum, cerebellum and brain stem. Concomitant treatment with cysteamine in doses of 50 and 100 mg/kg attenuated IDPN-induced decrease in vitamin E in cerebrum and cerebellum. There was a significant decrease in cerebral glutathione in IDPN treated rats, which was attenuated by cysteamine. No significant change was observed in the glutathione levels in cerebellum and brain stem. Further studies are deemed necessary to elucidate the mode of action of cysteamine and to determine therapeutic and/or prophylactic value of this drug in the treatment of movement disorders.

Animals↗

PubMed1995

Neuroprotective effect of selenium on iminodipropionitrile-induced toxicity.

The present investigation was undertaken to study the effect of selenium on experimental dyskinesia in rats. The movement disorders were produced in rats by intraperitoneal administration of iminodipropionitrile (IDPN) in the dose of 100 mg/kg per day for 12 days. Selenious acid was administered daily 30 minutes before IDPN in the doses of 5 mumol/kg, 10 mumol/kg and 20 mumol/kg bodyweight in three different groups of rats. Animals were observed daily for any neurobehavioral changes including circling, backwalking, head weaving and twitching. Immediately after behavioral studies, blood and brain specimens were collected for analysis of thiobarbituric acid reactive substances (TBARS) to measure the extent of free radical production. Our results showed that concurrent use of selenium significantly inhibited IDPN-induced neurobehavioral changes in a dose-dependent manner. Treatment of rats with selenium also reduced the TBARS production in blood and different regions of brain. These findings suggest that selenium attenuates the IDPN-induced neurotoxicity by inhibiting lipid peroxidation.

Animals↗

PubMed1994

Effect of (+/-)-verapamil and hydralazine on stress- and chemically-induced gastric ulcers in rats.

The influence of (+/-)-verapamil and hydralazine on stress- and various chemically-induced gastric ulcers in rats together with their influence on various biochemical parameters which affect the development of the induced ulcers was examined. Pretreatment of rats with (+/-)-verapamil (4-16 mg kg-1 orally) significantly decreased cold-stress-induced gastric ulcers and enhanced ethanol-induced ulcers. It did not affect indomethacin- (30 mg kg-1 orally) or reserpine- (5 mg kg-1 i.p.) induced ulcers. Pretreatment of the animals with hydralazine (1-10 mg kg-1 orally) significantly enhanced ethanol-, reserpine- and cold-stress-induced ulcers. It did not affect indomethacin-induced ulcers. Pretreatment of the animals with verapamil increased gastric mucus secretion, inhibited gastric acid secretion, decreased glutathione content and enhanced gastric lipid peroxidation whereas pretreatment of the animals with hydralazine significantly decreased gastric mucus secretion. Hydralazine did not affect gastric acid secretion, glutathione or gastric lipid peroxidation. The results of this study suggest that verapamil-induced protection against stress-induced ulcer may be due to its ability to suppress gastric acid secretion and to increase gastric mucus secretion. Its enhancement of ethanol-induced ulcers may be due to its ability to increase lipid peroxidation. The hydralazine-induced enhancement of the experimentally-induced ulcers may be due to its ability to suppress gastric mucus secretion.

Animals↗

PubMed1994

Effect of selenium and vitamin E on iminodipropionitrile induced dyskinesia in rats.

The present study was undertaken to determine the effect of combination of selenium and vitamin E on experimentally induced dyskinesia in rats. The dyskinetic syndrome was produced in 4 groups of 6 male rats each weighing 250-300g by intraperitoneal (ip) administration of iminodipropionitrile (IDPN) in doses of 100 mg/kg body weight daily for 12 days. A group of 6 rats (group 1) served as control and received normal saline only. The rats in group 2 (IDPN only) received normal saline (ip) 30 minutes before the administration of IDPN. The animals in groups 3, 4 and 5 received selenous acid (5 mumol/kg), vitamin E (500 mg/kg p.o.) and a combination of selenous acid and vitamin E respectively, daily, 30 minutes before IDPN for 12 days. Twenty four hours after the last dose of IDPN, the dyskinetic behavior including vertical head movements (retrocollis), horizontal head movements (laterocollis), circling and backwalking of each rat was studied for a period of 10 minutes. Immediately after behavioral studies, the animals were sacrificed and brains were dissected out for the analysis of conjugated dienes, lipid hydroperoxides and vitamin E. The results of this study showed that treatment of rats with IDPN only for 12 days produced dyskinetic syndrome in all the rats characterized by vertical and horizontal head movements, circling and backwalking. Concomitant treatment of rats with vitamin E and selenium individually reduced IDPN induced dyskinesia, and the symptoms were almost completely absent when the combination of these two agents was used.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Protective effect of Swertia chirata against indomethacin and other ulcerogenic agent-induced gastric ulcers.

The effect of Swertia chirata has been studied on experimentally induced gastric ulcers in rats. The ethanolic extract of chirata significantly reduced the intensity of gastric mucosal damage induced by indomethacin and necrotizing agents. It produced a significant decrease in gastric secretion in pylorus-ligated rats. The extract inhibited acetylcholine-induced contraction of guinea pig ileum, suggesting its anti-cholinergic activity. Pretreatment of rats with the extract significantly prevented ethanol-induced gastric wall mucus depletion and restored the non-protein sulfhydryl (NP-SH) content in the glandular stomachs. These findings support the use of chirata for the treatment of gastric ulcers in traditional medicine.

Animals↗

PubMed1991

Cod liver oil inhibits indomethacin induced gastropathy without affecting its bioavailability and pharmacological activity.

The upper gastrointestinal toxicity is one of the most common side effects associated with the use of nonsteroidal anti-inflammatory drugs (NSAIDs). Many attempts to prepare potent NSAIDs free from gastrotoxicity have failed. Hence, development of formulations to mask the gastropathy of NSAIDs are warranted. The present study was undertaken to investigate the effect of concomitant use of cod liver oil (CLO) on pharmacological activity and gastropathy of indomethacin in rats. The animals were treated with CLO (5 and 10 ml/kg body weight) along with indomethacin (30 mg/kg, body weight). Blood samples were collected for analysis of indomethacin at 0.25, 0.5, 1.0, 1.5, 2.0, 4.0, 6.0 and 24 hours. The anti-inflammatory activity of indomethacin alone and in combination with CLO was studied using carrageenan-induced paw oedema. Our studies related to the effect of these drugs on gastrointestinal tract showed that concurrent use of CLO protects gastric mucosa against indomethacin induced depletion of gastric wall mucus, non protein sulfhydryl (NP-SH) levels and gastric lesions. The result of this study also showed that the concurrent use of the CLO does not affect the bioavailability and anti-inflammatory activity of indomethacin while it inhibits the ulcerogenic effect of indomethacin in a dose dependent manner. These findings suggest that NSAIDs formulations containing CLO may reduce gastrotoxicity without affecting their therapeutic efficacy.

Administration, Oral↗

PubMed1991

The toxicity of Catha edulis (khat) in mice.

A large number of people in East Africa and Southern Arabia chew khat leaves because of its pleasurable and stimulating effects. Due to its habit forming property, the khat has been classified as a "Substance of Abuse" by the World Health Organization. In view of the large number of medical problems reported in khat chewers, the present study was undertaken to investigate the chronic toxicity of khat in mice. Three groups of mice were treated with aqueous solution of khat extract in the dose of 50, 100, and 200 mg/kg. body weight daily by oral intubation route for 6 weeks. The results indicated a dose-dependent decrease in body weight, an increase in the incidence of mortality and induction of site specific body and eye lesions. The histopathological examination of the lesions revealed reactive hyperplasia and necrosis in the lymphoid tissues. The necrotic areas in the subcutaneous tissues showed the presence of numerous polymorphs.

Animals↗

PubMed1991

Pharmacological studies on aerial parts of Calotropis procera.

The decoction of the aerial part of Calotropis procera is commonly used in Saudi Arabian traditional medicine for the treatment of variety of diseases including fever, joint pain, muscular spasm and constipation. The present investigation was undertaken to confirm its claimed activity in traditional medicine. The ethanol extract of the plant was tested on laboratory animals for its antipyretic, analgesic, anti-inflammatory, antibacterial, purgative and muscle relaxant activities. The results of this study showed a significant antipyretic, analgesic and neuromuscular blocking activity. On smooth muscle of guinea pig ileum, the extract produced contractions which was blocked by atropine supporting its use in constipation. The extract failed to produce significant anti-inflammatory and antibacterial activities. Our phytochemical studies on the aerial parts of C. procera showed the presence of alkaloids, cardiac glycosides, tannins, flavonoids, sterols and/or triterpenes. However, the chemical constituents responsible for the pharmacological activities remains to be investigated. The safety evaluation studies revealed that the use of extract in single high doses (up to 3 g/kg) does not produce any visible toxic symptoms or mortality. However, prolong treatment (90 days) causes significantly higher mortality as compared to control group.

Animals↗

PubMed1990

An evaluation of the male reproductive toxicity of cathinone.

(-)-Cathinone is the major psychoactive component of khat plant (Catha edulis Forssk.). Khat has been shown to produce reproductive toxicity in human beings and experimental animals. However, the chemical constituents of khat leaves responsible for sexual dysfunction are not known. In the present study cathinone enantiomers have been investigated for their reproductive toxicity in rats. Cathinone produced a dose-dependent decrease in food consumption and suppressed the gain in body weight. There was a significant decrease in sperm count and motility and increase in the number of abnormal sperms in cathinone treated animals. Histopathological examination of testes revealed degeneration of interstitial tissue, cellular infiltration and atrophy of Sertoli and Leydig's cells in cathinone treated animals. Cathinone also produced a significant decrease in plasma testosterone levels of the rats. Although both enantiomers of cathinone produced deleterious effects on male reproductive system, (-)-cathinone was found to be more toxic. From this study it may be concluded that the cathinone content in khat may be partially or totally responsible for the reproductive toxicity in khat chewers.

Alkaloids↗