Biomedical subjects

M Ali

Publications and source records attributed to M Ali.

At least 127 records · Page 7Linked to original sources

PubMed1999

Effect of raw versus boiled aqueous extract of garlic and onion on platelet aggregation.

The effects of aqueous extracts of raw and boiled garlic and onions were studied in vitro on the collagen-induced platelet aggregation using rabbit and human platelet-rich plasma. A dose dependant inhibition of rabbit platelet aggregation was observed with garlic. Onion also showed dose-dependent inhibitory effects on the collagen-induced platelet aggregation but this inhibition was of a lesser magnitude compared to garlic when related to dose. The concentration required for 50% inhibition of the platelet aggregation for garlic was calculated to be approximately 6.6 mg ml(-1) plasma, whereas the concentration for onion was 90 mg ml(-1) plasma. Boiled garlic and onion extracts showed a reduced inhibitory effect on platelet aggregation. Garlic but not onion significantly inhibits human platelet aggregation in a dose-dependent fashion. The potency of garlic in inhibiting the collagen-induced platelet aggregation is approximately similar to that of rabbit platelets (8.8 mg ml(-1) produced 50% inhibition of platelet aggregation). The results of this study show that garlic is about 13 times more potent than onion in inhibiting platelet aggregation and suggest that garlic and onion could be more potent inhibitors of blood platelet aggregation if consumed in raw than in cooked or boiled form.

Animals↗

PubMed1999

Hypotensive, hypoglycaemic and toxicological studies on the flavonol C-glycoside shamimin from Bombax ceiba.

Shamimin, a C-flavonol glucoside from Bombax ceiba leaves showed significant potency as a hypotensive agent at the doses of 15 mg/kg, 3 mg/kg, 1 mg/kg and significant hypoglycaemic activity at 500 mg/kg in Sprague-Dawley rats. Further studies revealed that it did not cause any mortality in mice at the dose of 1 g/kg but in rats 500 mg/kg is a lethal dose. Aqueous and methanolic extracts of Bombax ceiba leaves and one of its fractions were also subjected to pharmacological and toxicological screening.

Animals↗

PubMed1999

Shamimin: a new flavonol C-glycoside from leaves of Bombax ceiba.

Shamimin a new flavonol C-glycoside has been isolated as a pale yellow powder from the ethanolic extract of fresh, undried leaves of Bombax ceiba. Its structure has been elucidated as 2-(2,4,5-trihydroxyphenyl)-3,5,7-trihydroxy-6-C- glucopyranosyloxy-4H-1-benzopyran-4-one through extensive spectroscopic methods (IR, mass, 1H- and 13C-NMR), and 2D-NMR experiments. Shamimin showed antimicrobial activity against a few bacteria and fungi.

Anti-Bacterial Agents↗

PubMed1999

Measurement of serum N-acetyl beta glucosaminidase activity in patients with breast cancer.

N-acetyl-beta-glucosaminidase (NAG) activity measured in sera from 129 breast cancer patients was elevated (mean 18.2 units/l) compared with that in sera from 28 healthy women (11.6 units/l) (p=0.001). There was a weak correlation between NAG activity and carcinoembryonic antigen (CEA) and CA-153, but no relationship to age, menopausal status, node status, stage, histology of tumour or to steroid receptors. NAG, CEA and CA-153 were measured in periodic follow-up samples taken after surgery (up to 26 months) from 17 patients. NAG activity fluctuated within a narrow range, unlike CEA and CA-153. In 70% of cases the pattern was similar to at least one of the other markers, and was generally maintained at a higher level in patients who suffered relapse compared with those who remained disease-free up to the last follow-up, but was not significantly altered before relapse. The measurement of NAG activity is unlikely to be of value in predicting time or occurrence of relapse or of clinical utility in post-surgical therapy. Increased appearance in serum may aid metastasis by degrading the extracellular matrix and it may be better investigated as a predictor of progression from in situ to invasive and metastatic cancer.

Acetylglucosaminidase↗

PubMed1999

Immunoradiometric measurement of pS2 in breast cancer--correlation with steroid receptors and plasminogen activators.

pS2 was measured by radioimmunometric assay in tumour extracts from 197 breast cancer patients. Values ranged from 0 to 50 ng/mg protein (mean 9.6 and median 3 ng/mg). We found no correlation with age, menopausal status, nodal metastases, disease stage or tumour histology. There was, however, a linear relationship with both ER (p < 0.0001) (particularly nuclear ER) and PR (p < 0.0001) expression determined by enzyme immunoassay (ELISA), as well as a good correlation when high and low expressors were stratified on the basis of combined ER/PR expression using consensus cut-off points. Only 15% of ER - ve/PR - ve patients were classified as pS2 + ve compared with 83% of those who were ER + ve/PR + ve. pS2 was also directly correlated with high expression of tPA and inversely with uPA. Comparison with previous studies showed that the current ELISA method produced consistent results, in contrast to other methods, particularly those based on immunohistochemical detection. The close relationship between pS2 and both steroid receptors suggests that pS2 may be important in terms of defining hormone-responsive patients who are likely to benefit from endocrine therapy.

Breast Neoplasms↗

PubMed1999

Localization of regulatory protein binding sites in the proximal region of human myometrial connexin 43 gene.

Parturition is preceded by a large increase in gap junctions between myometrial smooth muscle cells. Connexin 43 is the major structural protein of myometrial gap junctions. To explore transcriptional regulation of the myometrial Cx43 gene, we used DNase I footprinting, electrophoretic mobility shift and transient transfection assays to examine a 312 bp promoter region (-164 to +148) of the gene, utilizing human myometrial cell cultures and nuclear extracts. The DNase I studies showed four regions of nucleoprotein interactions. Protection of region 1 (-80 to -31) encompassed an Activator Protein 1 (AP1) (-44 to -36) and two Specificity Protein 1 (Sp1) (-77 to -69 and -59 to -48) consensus sequences. Regions 2 to 4 included the transcription initiation site (-10 to +25), an Ets/NF-kB consensus sequence (+47 to +74) and a TA-rich region (+81 to +101) respectively. Gel mobility shift and supershift assays demonstrated c-Jun and Sp1 binding at the AP1 and Sp1 sites respectively. Promoter mutagenesis and transient transfection analyses combined with Sp1 and c-Jun/c-Fos over-expression studies indicate that both Sp1 and c-Jun are required for maximal promoter activity and, therefore, may positively regulate transcription of myometrial Cx43 during the initiation of labour.

Base Sequence↗

PubMed1999

Hypertonic saline nasal provocation stimulates nociceptive nerves, substance P release, and glandular mucous exocytosis in normal humans.

Hypertonic saline (HTS) induces bronchoconstriction. Potential mechanisms were evaluated in a human nasal provocation model. Aliquots of normal saline (1 x NS, 100 microliters) and higher concentrations (3 x NS, 6 x NS, 12 x NS, 24 x NS) were sprayed into one nostril at 5-min intervals. Lavage fluids were collected from the ipsilateral and contralateral sides to determine the concentrations of specific mucus constituents. Nasal cavity air-space volume was assessed by acoustic rhinometry (AcRh). The distribution of substance-P-preferring neurokinin-1 (NK-1) receptor mRNA was assessed by in situ reverse transcriptase-polymerase chain reaction. Unilateral HTS induced unilateral dose-dependent increases in sensations of pain, blockage, and rhinorrhea, the weights of recovered lavage fluids, and concentrations of total protein, lactoferrin, mucoglycoprotein markers, and substance P. Contralateral, reflex-mediated effects were minor. There were no changes in IgG or AcRh measurements. NK-1 receptor mRNA was localized to submucosal glands. HTS caused pain with unilateral substance P release. The presumed nociceptive nerve efferent axon response led to glandular exocytosis, presumably through actions on submucosal gland NK-1 receptors. Vascular processes, including plasma exudation, filling of venous sinusoids, and mucosal edema were not induced in these normal subjects.

Administration, Intranasal↗

PubMed1999

Adrenocorticotropin responses to naloxone in sons of alcohol-dependent men.

The endogenous opioid system is part of a neural circuitry functionally related to alcohol-seeking behaviors. A family history of alcoholism is the strongest predictor of future development of alcohol dependence. This study was designed to evaluate ACTH responses to opioid receptor blockade as a function of family history for alcohol dependence. The nonselective opioid antagonist naloxone stimulates ACTH secretion by blocking opioidergic input on paraventricular corticotropin-releasing factor neurons, thereby providing a methodology for comparing hypothalamic opioid tone between study groups. Sixty nonalcoholic subjects, aged 18-25 yr, were enrolled in a protocol to measure the ACTH response to naloxone. Thirty-two subjects were offspring from families with a high density of alcohol dependence and were designated as family history-positive subjects. Twenty-eight subjects were offspring of nonalcohol-dependent parents and were designated family history-negative subjects. Subjects received naloxone (125 microg/kg) or placebo (0.9% saline) in double blind, randomized order. Plasma ACTH was monitored. Family history-positive men had increased ACTH response to naloxone compared to 1) family history-positive women, 2) family history-negative men, and 3) family history-negative women. Despite differences in plasma ACTH levels after naloxone administration, plasma naloxone concentrations did not differ between study groups. This finding suggests that nonalcoholic male offspring of alcohol-dependent men have altered endogenous opioid activity directed at hypothalamic corticotropin-releasing factor neurons.

Adolescent↗

PubMed1999

Effects of environmental factors on child survival in Bangladesh: a case control study.

The need for further studies on relationships between deaths and environmental variables has been reported in the literature. This case-control study was, therefore, carried out to find out the associations between several social and environmental variables and deaths of children due to infectious diseases such as those leading to diarrhoea, acute respiratory infection, measles and other diseases. Six hundred and twenty-five deaths (cases) and an equal number of matched living children (controls) aged 1-59 months, were studied in rural Matlab. An analysis of crude and adjusted odds ratio showed differential associations. Sources of drinking water, amount of stored water, conditions of latrines, number of persons sleeping with the child and the type of cooking site were statistically significantly associated with deaths due to infectious diseases after controlling for breast feeding, immunization, and the family size. Significant associations were also observed between: (i) the sources of drinking water and deaths due to ARI, and (ii) conditions of latrines and deaths due to diarrhoeal diseases, after controlling for the confounding variables. Several other environmental factors also showed associations with these various death groups, but they were not statistically significant. The size of the samples in death groups (small) and the prevalence of more or less homogeneous environmental health conditions probably diminished the magnitude of the effects. The results of the study reconfirm the importance of environmental health intervention in child survival, irrespective of breast-feeding, immunization, and selected social variables.

Bangladesh↗

PubMed1999

Adrenocortical responses and family history of alcoholism.

BACKGROUND: This study was designed to assess whether nonalcoholic offspring from families with a high density of alcohol-dependent individuals have altered hypothalamic-pituitary-adrenal (HPA) axis dynamics compared with nonalcoholic subjects without a family history of alcohol dependence. METHODS: Seventy-eight nonalcoholic subjects aged 18 to 25 were enrolled in the protocol. Thirty-nine subjects were offspring from families with a high density of alcohol dependence and were designated as family history-positive (FHP) subjects. Thirty-nine subjects were biological offspring of nonalcohol-dependent parents and were designated as family history-negative (FHN) subjects. Subjects received naloxone hydrochloride (0 and 125 microg/kg) and cosyntropin (0, 0.25 microg, and 250 microg) in double-blind, randomized order and cortisol was monitored. A subset of subjects (11 FHP, 11 FHN) was admitted to the General Clinical Research Center to measure serum cortisol levels every 30 min for 24 hr. RESULTS: FHP subjects had an increased cortisol response to opioid receptor blockade induced by naloxone. However, no group differences in cortisol were uncovered during administration of cosyntropin or during monitoring of the cortisol circadian profile. CONCLUSION: These observations suggest that differences in the cortisol dynamics between FHP and FHN subjects are unmasked by opioid receptor blockade directed at the hypothalamus, but not when cortisol levels are directly provoked at the level of the adrenal gland. In addition, unprovoked cortisol secretion monitored over a 24-hr interval cannot distinguish FHP from FHN subjects.

Adolescent↗

PubMed1999

The effects of glibenclamide on serum lipids and lipoproteins in type II non-insulin dependent diabetes mellitus.

OBJECTIVE: To examine the effects of glibenclamide treatment on plasma lipids and lipoprotein levels. SETTINGS: Out patients of Type II diabetics from department of Baqai Diabetes and Endocrine Centre and two other diabetic clinics of Karachi. METHODS: The effects of glibenclamide on blood glucose and various aspects of lipoproteins has been studied in 26 (14 male, 12 female) Type II Diapetes patients before and after 12 weeks of glibenclamide therapy. Treatment was initiated with 5 mg oral glibenclamide with diet control. The initial dosage of glibenclamide was 5 mg/day taken half an hour before meal; this was increased to 5 mg per week and was adjusted according to the patient's tolerance to the drug and their glycemic control. RESULTS: The results demonstrated that fasting blood glucose declined from 221.53 + 7.84 to 165.02 + 5.12 mg/dl, (P < 0.001). There was a statistically significant increase in the plasma high-density lipoprotein cholesterol from 33.60 + 1.00 to 37.07 + 1.05 mg/dl, (P << 0.05). Total cholesterol, triglycerides, low-density lipoprotein cholesterol and very-low-density lipoprotein cholesterol did not change significantly. CONCLUSION: Improved glycaemic control in patients treated with glibenclamide with Type II Diabetes was achieved which lead to changes in lipoprotein metabolism. There was no evidence of changes in lipoproteins in directions associated with an increased risk for atherosclerosis.

Blood Glucose↗

PubMed1999

Definition of Nidana Pancaka (first chapter of Madhavanidana).

This is in continuation of the previous article published in this Bulletin of the Indian Institute of the History of Medicine, Volume XXVII, No. 2, July 1997. P. Nos 163 to 171, under the title of "Definition of Nidana Panchaka (First Chapter of Madhava Nidana"). It deals with Nadana, Purvarupa, Rupa, Upashaya and Samprapti as described in the first Chapter of Madhavanidana.

History, Ancient↗

PubMed1999

Ayurvedic literature in Urdu (Part-II).

This article is a second part of previous work published with the same title in this Bulletin Vol. 28, 1998, P. nos. 151-158. It contains brief notes on six rare Ayurvedic books in Urdu. It provides two types of information, i.e. (i) Introduction to the books studied and (2) Literary history of Ayurveda of that period in which Urdu language had a prominent role in propagation of Arts and Science. It gives an idea for seeking information on these lines regarding the Ayurvedic works in Arabic and Persian also.

History, Early Modern 1451-1600↗

PubMed1998

Urothelial synthesis of prostanoids in the ovine ureter.

The purpose of this study was to investigate the site of production (urothelium/smooth muscle) and quantitative release of prostanoids in the ureter. Quantitative analysis of prostacyclin (PGI2) was by its metabolite, 6-keto PGFalpha, thromboxane (TXB2) and prostaglandin F2alpha. Synthesis by radiometry and radioimmunoassay was performed in vitro in sheep ureter specimens before and after removal of the inner epithelial layer and after addition of indomethacin. The major prostanoids present in the ureter were PGI2 and TXB2; PGI2 was quantitatively the largest component. Removal of the thin inner epithelial layer (urothelium) reduced mostly PGI2; addition of arachidonic acid significantly augmented PGI2 only in ureters with intact urothelium but did not alter TXB2 levels. The main source of prostanoid synthesis (PGI2) of the ureter is to be found in the urothelium. The functional role of the prostanoids may be related to coordination of peristalsis.

6-Ketoprostaglandin F1 alpha↗

PubMed1998

Purification of a toxic factor from Arabian Gulf catfish epidermal secretions.

The Arabian Gulf catfish, Arius bilineatus (Valenciennes) secretes a proteinaceous epidermal secretion when threatened or injured. A toxic factor has been isolated and purified from the crude extract (crude skin toxin) of these secretions by a combination of gel filtration on Sephacryl S-300 and preparative discontinuous polyacrylamide gel electrophoresis. The purified skin toxin has a molecular weight of 39,000 Da and an isoelectric point (pI) of 5.45. Injection of the purified skin toxin into rabbits i.v. and determination of the LD50 indicated that the protein had been purified approximately 30 fold by these procedures. Injection of the purified skin toxin into rabbits caused agitation, convulsions and death within 5 min. Analysis of plasma levels of lactate dehydrogenase, glutamate-oxaloacetate transaminase and glutamate pyruvate transaminase in injected rabbits indicated that the skin toxin caused cardiac and liver damage to the animals.

Alanine Transaminase↗

PubMed1998

Prostanoid synthesis in whole blood cells from fish of the Arabian Gulf.

The ability to synthesise prostaglandins and thromboxane from 14C-labelled arachidonic acid was investigated in 11 species of fish from the Arabian Gulf. Cyclooxygenase activity was assessed in washed whole blood cells. Arachidonic acid and its metabolites were extracted and separated on silicic acid columns and thin layer chromatography (silica gel G). Total capacity to convert [14C]arachidonic acid to prostanoids varied from 1 to 35% among the 11 fish species studied. Gray shark (Chiloscyllium griseum) blood cells had the highest capacity (37 +/- 0.4%) to convert arachidonate into prostanoids and two species of catfish (Arius bilineatus and A. thalassinus) exhibited greater than 10% capacity to convert [14C]arachidonate into prostanoids. The major prostanoid synthesised by the two catfish (A. bilineatus and A thalassinus) was 6-keto PGF1 alpha, a stable metabolite of prostacyclin, PGI2. In contrast, A. teunispinis synthesised thromboxane B2, a stable metabolite of thromboxane A2. Thromboxane B2 (TXB2) was the major product synthesised by all three species of shark studied (Chil. griseum, Carcharhinus plumbeus, Carch. melanopterus), with 6-keto PGF1 alpha a minor product. Other fish studied showed a varied pattern of prostanoid synthesis. The synthesis of these prostanoids was almost completely blocked by preincubation of the whole blood cells from catfish and shark with indomethacin (0.5 microM) suggesting the involvement of cyclooxygenase-mediated prostanoid synthesis.

6-Ketoprostaglandin F1 alpha↗

PubMed1998

Effects of aqueous extract of onion on the liver and lung of rats.

The toxic effects of oral and intraperitoneal administration of onion extracts on lung and liver tissue of rats were investigated. Oral or intraperitoneal administration of low doses of onion (50 mg/kg) to rats had little effect on lung and liver tissues when compared to control animals. In contrast, administration of high doses of onion (500 mg/kg) resulted in apparent histological changes in lung and liver tissues of rats. Intraperitoneal administration of the high dose of onion was more damaging to lung and liver tissue than oral administration and resulted in a 25% rate of mortality in this treatment group. These results suggest that low doses of onion are nontoxic and may be administered with few ill effects.

Animals↗

PubMed1998

Detection of 8-epi prostaglandin F2alpha in an extract of epidermal secretion of the catfish from the Arabian Gulf.

We provide herein mass spectrometric evidence for the existence of F2 isoprostanes in an epidermal secretion of the catfish from the Arabian Gulf. The compounds were extracted, purified by thin layer chromatography (TLC) and derivatized into the pentafluorobenzyl trimethylsilyl (PFB-TMSi) derivatives and quantified using SIM-negative ion gas chromatography-mass spectrometry based on the addition of tetradeuterated 8-epi PGF2alpha as internal standard prior to sample workup. Freshly collected secretions from the male catfish contained 5.63 and 4.17 ng/ml (two determinations) and from the female catfish 3.60 and 3.81 ng/ml (two determinations) of free 8-epi PGF2alpha. The level of these compounds increases approximately 8-fold upon storage of the extract at -20 degrees. In view of the potent reported actions of F2 isoprostanes on vasoconstriction and as thromboxane receptor antagonists, the presence of isoprostanes in the catfish secretions may contribute to the reported ulcer healing properties of these secretions.

Animals↗