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S Qureshi

Publications and source records attributed to S Qureshi.

At least 19 recordsLinked to original sources
PubMed2006

Studies on the cytological and biochemical effects of valerian in somatic and germ cells of Swiss albino mice.

Valerian is widely known for its use as a sedative and an anti-anxiety drug in the folk medicine. Literature reports suggested valerian to induce genotoxicity in vitro (ECV304 cells) by reactive oxygen species-mediated mechanism; however, there are no reports on its genotoxicity and/or the epigenetic mechanism in vivo. In view of the folkloric significance, it was found worthwhile to (1) determine the genotoxic effects of valerian in somatic and germ cells of mice and (2) investigate the role of epigenetic mechanisms. The protocol included the oral treatment of mice with different doses (500, 1000 and 2000 mg/kg/day) of valerian for 7 days. The following experiments were conducted: (i) cytological studies on micronucleus test, (ii) cytogenetic analysis for meiotic chromosomes, (iii) cytological analysis of spermatozoa abnormalities, (iv) quantification of proteins and nucleic acids in testicular cells and (v) estimation of malondialdehyde (MDA) and nonprotein sulfhydryl (NP-SH) in hepatic and testicular cells. The treatment increased the frequency of micronuclei in the polychromatic erythrocytes (PCE) and decrease the ratio of PCE to normochromatic erythrocytes (NCE) in the femur. It caused aberrations in chromosomes of the testis and induced spermatozoa abnormalities. The concentration of nucleic acids was depleted in the testicular cells. These changes might be attributed to the epigenetic mechanisms as revealed by an increase in the concentrations of MDA and a decrease of NP-SH levels in hepatic and testicular cells observed in the present study. The observed changes may be ascribed to terpenoids (valepotriates) and flavonoids (6-methylapigenin and 2S(-)-hesperidin) present in valerian.

Administration, Oral↗
PubMed2006

Studies on the reproductive, cytological and biochemical toxicity of Ginkgo Biloba in Swiss albino mice.

Ginkgo biloba (an herbal product), used as a folkloric medicine in the treatment of dementia, was evaluated for its effects on reproductive, cytological and biochemical toxicity in male Swiss albino mice. The mice were treated with different doses (25, 50 and 100mg/kg/day) of the aqueous suspension of Ginkgo biloba for 90 days by oral gavage. The following parameters were evaluated: (1) reproductive organ weight; (2) motility and content of sperms; (3) spermatozoa morphology; (4) cytology of the testes chromosomes; (5) study on reproduction; (6) biochemical study on proteins, nucleic acids, malondialdehyde (MDA) and nonprotein sulfhydryl (NP-SH). The treatment caused significant changes in the weight of caudae epididymis, prostate, chromosomal aberrations, rate of pregnancy and pre-implantation loss. However, the percent motility, sperm count and morphology of spermatozoa were not affected. Our study on biochemical parameters showed depletion of nucleic acids, NP-SH and increase of MDA, which elucidated the role of free radical species in the induced changes in testis chromosomes and the reproductive function. The exact mechanism is not known, however, the activation of GABA, glycine and glutamate under the influence of Ginkgo biloba and its constituents might have generated free radicals and depleted cellular glutathione by calcium influx and membrane depolarization. The observed toxicity is attributed to the toxic constituents (ginkgolic acids, biflavones, cardanols, cardols, bilobalides and quercetin) of Ginkgo biloba. Our results warrant careful use of Ginkgo biloba as a remedy for impotence and/or erectile dysfunction.

Animals↗
PubMed2005

Topical nonsteroidal anti-inflammatory drugs versus oil of evening primrose in the treatment of mastalgia.

OBJECTIVE: To compare oil of evening primrose (OEP) and topical nonsteroidal anti-inflammatory (NSAIDs) with respect to safety, effectiveness, rapidity of response, cost effectiveness and acceptability in the treatment of breast pain. STUDY DESIGN: An open, non-randomised, comparative study of topical (NSAI) gel versus OEP was carried out, over a period of one year. PATIENTS AND METHODS: Fifty female patients attending the outpatient department with moderate to severe breast pain were given one of the two agents alternatively, after selection. RESULTS: Results showed that out of 25 patients treated with OEP, 64% had a clinically significant response after three months of treatment, compared with 92% with topical NSAIDs. Only one patient (4%) had side effects with OEP, while no patient had side effects with topical NSAIDs. Twenty per cent and seventy per cent showed acceptability as far as costs were concerned and mode of administration respectively, with OEP. The acceptability rate was 68% and 96% respectively, with topical NSAIDs. CONCLUSION: This study has shown topical NSAIDs to be safe, effective, rapid and acceptable mode of treatment for cyclical and non-cyclical mastalgia.

Administration, Topical↗
PubMed2005

In situ DMSO hydration measurements of HTS compound libraries.

Compounds used in high throughput screening (HTS) are typically dissolved in DMSO. These solutions are stored automation-friendly racks of wells or tubes. DMSO is hygroscopic and quickly absorbs water from the atmosphere. When present in DMSO compound solutions, water can accelerate degradation and precipitation. Understanding DMSO hydration in an HTS compound library can improve storage and screening methods by managing the impact of water on compound stability. A non-destructive, acoustic method compatible with HTS has been developed to measure water content in DMSO solutions. Performance of this acoustic method was compared with an optical technique and found to be in good agreement. The accuracy and precision of acoustic measurements was shown to be under 3% over the tested range of DMSO solutions (0% to 35% water by volume) and insensitive to the presence of HTS compounds at typical storage concentrations. Time course studies of hydration for wells in 384-well and 1536-well microplates were performed. Well geometry, fluid volume, well position and atmospheric conditions were all factors in hydration rate. High rates of hydration were seen in lower-volume fills, higher-density multi-well plates and when there was a large differential between the humidity of the lab and the water content of the DMSO. For example, a 1536-well microplate filled with 2microL of 100% DMSO exposed for one hour to a laboratory environment with approximately 40% relative humidity will absorb over 6% water by volume. Understanding DMSO hydration rates as well as the ability to reverse library hydration are important steps towards managing stability and availability of compound libraries.

Acoustics↗
PubMed2004

Supranormal renal function in unilateral hydronephrotic kidney can be avoided.

INTRODUCTION: There are reports and controversy in the literature of supranormal (defined as >55%) differential renal function (DRF) in the hydronephrotic kidney in children with unilateral hydronephrosis. It is not confirmed whether supranormal DRF is an artifact or a true finding. In patients in whom the relative renal function deteriorates, relief of obstruction becomes surgically necessary and if this artifact can be removed. Supranormal function in an obstructed kidney is confusing and there is no consensus on how to manage these patients. There is no agreement if this is a true entity or an artifact. We wanted to address this issue by reporting our experience. METHODS: We reviewed all the consecutive cases from August 2000 to October 2001 who were studied in our center with the diagnosis of unilateral renal obstruction for confirmation or evaluation of DRF. All patients had MAG-3 studies that were interpreted by experienced nuclear medicine physicians. The DRF were measured within the first to second minute of the MAG-3 injection. Regions of interest were drawn by the imaging software and the images were corrected for background counts by drawing regions of interest 2 pixels away from the edge of the renal cortex. RESULTS: Fifty-seven patients were confirmed to be obstructed unilaterally; 41 (72%) patients had obstructive lesions in the left kidney and 16 (28%) in the right kidney. There was no case of supranormal DRF in the obstructed kidneys in our study. CONCLUSION: The supranormal renal function, as noted in some reports in the literature, was not seen in any patients at our institution. We believe that this entity is an artifact and can be avoided by using MAG-3 and projecting regions of interest by computer software; we plan to start analyzing multiple algorithms in phantoms with different ROI selection for background analysis.

Artifacts↗
PubMed2004

Improving the quality of health care: using international collaboration to inform guideline programmes by founding the Guidelines International Network (G-I-N).

Clinical practice guidelines are regarded as powerful tools to achieve effective health care. Although many countries have built up experience in the development, appraisal, and implementation of guidelines, until recently there has been no established forum for collaboration at an international level. As a result, in different countries seeking similar goals and using similar strategies, efforts have been unnecessarily duplicated and opportunities for harmonisation lost because of the lack of a supporting organisational framework. This triggered a proposal in 2001 for an international guidelines network built on existing partnerships. A baseline survey confirmed a strong demand for such an entity. A multinational group of guideline experts initiated the development of a non-profit organisation aimed at promotion of systematic guideline development and implementation. The Guidelines International Network (G-I-N) was founded in November 2002. One year later the Network released the International Guideline Library, a searchable database which now contains more than 2000 guideline resources including published guidelines, guidelines under development, "guidelines for guidelines", training materials, and patient information tools. By June 2004, 52 organisations from 27 countries had joined the network including institutions from Oceania, North America, and Europe, and WHO. This paper describes the process that led to the foundation of the G-I-N, its characteristics, prime activities, and ideas on future projects and collaboration.

Humans↗
PubMed2001

Boric acid enhances in vivo Ehrlich ascites carcinoma cell proliferation in Swiss albino mice.

The influence of boric acid, a boron carrier, on Ehrlich ascites carcinoma (EAC) cell-bearing mice was investigated in view of its importance in the boron neutron capture therapy and the influence of boron on proliferation and progression of cancer cells mediated by proteoglycans and collagen. The present study included the evaluation of boric acid for the effects on total count and viability of EAC cells in addition to their non-protein sulfhydryls (NP-SH) and malondialdehyde (MDA) contents as parameters for conjugative detoxication potency and possible oxidative damage. The EAC cell-bearing animals were also observed for the effect on survival, body weight changes, and histopathological evaluation of the tumors grown at the site of inoculation. The treatment with boric acid significantly increased the total number of peritoneal EAC cells and their viability. A significant increase in the body weight was observed that dose-dependently reached plateau levels by 20 days of treatment. Conversely, a reduction in the duration of survival of these animals was evident with the same protocol. Boric acid treatment resulted in a decrease in NP-SH contents with a concomitant increase in MDA levels in EAC cells as revealed by the results of the biochemical analysis. These data are supported by our results on histopathological investigations, which apparently showed fast growth, in addition to several mitotic figures and mixed inflammatory reaction, after treatment with boric acid. It seems likely that a particular combination of properties of boric acid, rather than a single characteristic alone, will provide useful information on the use of this boron carrier in neutron capture therapy.

Animals↗
PubMed2001

General practitioners' and patients' models of obesity: whose problem is it?

Primary care literature emphasises the importance of agreement and shared models in the consultation. This study compared general practitioners' (GPs') and patients' models of obesity. Questionnaires concerning beliefs about the causes, consequences and solutions to obesity were completed by 89 general practitioners (GPs) and 599 patients from practices across UK. In terms of causes, the results showed that the patients were more likely to attribute obesity to a gland/hormone problem, slow metabolism and stress than the GPs, whereas the GPs were more likely to blame eating too much. In terms of consequences, the patients rated difficulty getting to work more highly whereas the GPs regarded diabetes as more important. For the solutions to obesity, the two groups reported similar beliefs for a range of methods, but whereas the patients rated the GP and a counsellor as more helpful, the GPs rated the obese person themselves more highly. It is argued that patients show a self serving model of obesity by blaming internal uncontrollable factors for causing obesity yet expecting external factors to solve it. In contrast, GPs show a victim blaming model by attributing both cause and the solution to internal controllable factors. Such differing models have implications regarding the form of intervention likely to be used in primary care and indicate that whereas patients would prefer a more professional based approach, GPs would prefer a more patient-led one. Further, the results suggest that even if an intervention could be negotiated, success rates would be low as either the patient or the GP would be acting in contradiction to their beliefs about the nature of obesity.

Adult↗
PubMed2001

A low-cost intervention for cleaner drinking water in Karachi, Pakistan.

OBJECTIVE: To pilot test an inexpensive, home-based water decontamination and storage system in a low-income neighborhood of Karachi. METHODS: Fifty households received a 20-L plastic water storage vessel with a high-quality spout and a regular supply of diluted hypochlorite solution. Twenty-five control households were recruited. Water samples were collected at baseline and during unannounced follow-up visits 1, 3, 6, and 10 weeks later. RESULTS: Baseline drinking water samples among intervention households were contaminated with a mean 9397 colony-forming units (cfu)/100 mL of thermotolerant coliforms compared with a mean 10,990 cfu/100 mL from controls. After intervention the mean concentration of thermotolerant coliforms decreased by 99.8% among the intervention households compared with an 8% reduction among controls. Two years after vessel distribution, 34 (68%) of the families were still using the vessel. Thirteen of the households had stopped using their vessel because it had broken after more than 6 months of use, a pattern most consistent with ultraviolet radiation-induced degradation of the plastic. CONCLUSIONS: In a highly contaminated environment, a specifically designed water storage container and in-home water chlorination was acceptable and markedly improved water quality. Where plastic water vessels will be exposed to substantial sunlight, ultraviolet light stabilizers should be incorporated into the plastic.

Costs and Cost Analysis↗
PubMed2001

Outcome of staged reconstructive surgery for hypoplastic left heart syndrome following antenatal diagnosis.

BACKGROUND AND AIMS: Staged reconstructive surgery has radically altered the prognosis of hypoplastic left heart syndrome (HLHS). Antenatal diagnosis allows for appropriate counselling, and time to consider treatment options. We report outcome from a centre where most cases are antenatally diagnosed and delivered on site. METHODS: Information was collated on 188 consecutive cases of HLHS between 1995 and 2000, including timing of diagnosis, outcome of pregnancy, and age and outcome at each stage of surgery. At Guy's Hospital, 174 cases were diagnosed antenatally, of whom 50 underwent surgery. Fourteen others (five diagnosed antenatally at other centres, and nine diagnosed postnatally) also underwent surgery. RESULTS: Survival after stage I (the Norwood operation) was 52% (33/64). Postoperative survival after stage II (the hemi-Fontan operation, performed in 29), and stage III (the Fontan operation, performed in 10), was 100%. Two late deaths occurred 3 and 10 months after stage II, giving overall survival of 48% (31/64). At follow up, three children have neurological impairment, and one had poor right ventricular function necessitating cardiac transplantation. CONCLUSIONS: Antenatal diagnosis allows informed decisions about treatment options, and facilitates preoperative care. Mortality following stage I is high, irrespective of timing of diagnosis, but medium term outcome for survivors is good.

Cardiac Surgical Procedures↗
PubMed2000

Effect of ninhydrin on the biochemical and histopathological changes induced by ethanol in gastric mucosa of rats.

Studies on the effect of ninhydrin in the normal gastric mucosa and against the ethanol induced gastric injury were undertaken in rats in view of the presence of a carbonyl function as well as hydroxyl groups in its chemical structure. In spite of its potentials to generate hydroxyl radicals, it is deemed to possess antioxidant property by virtue of its electrophilic nature. Recent studies have shown gastro-protection to mediate through a reaction between the electrophilic compounds and sulfhydryl groups of the mucosa. Hence it was found worthwhile to evaluate the interaction between the oxidant and antioxidant functions in the structure of the same compound. The effects of ninhydrin pretreatment on gastric mucosal injuries caused by 80% ethanol, 25% NaCl and 0.2M NaOH were investigated in rats. The gastric tissue in ethanol-treated rats was analyzed for different histopathological lesions. In addition, the effects on ethanol-induced changes in the gastric levels of proteins, nucleic acids, non-protein sulfhydryl (NP-SH) and malondialdehyde (MDA) were also evaluated. Ninhydrin, as such, failed to induce any significant changes in normal gastric mucosa, while its pretreatment at oral doses of 5, 10 and 20 mg/kg was found to provide a dose-dependent protection against the ulcers induced by ethanol, NaOH and NaCl. The results of histopathological evaluation revealed a protective effect of ninhydrin on congestion, hemorrhage, edema, erosions and necrosis caused by ethanol. Furthermore, the pretreatment afforded a dose-dependent inhibition of the ethanol-induced depletion of proteins, nucleic acids, NP-SH and increase of MDA in the gastric tissue. The results obtained clearly demonstrate the anti-ulcerogenic activity of ninhydrin. The exact mechanism of action is not known. However, the carbonyl function in ninhydrin appears to achieve antioxidant balance and protect the gastric mucosa from the ethanol-induced gastric injury. Further studies are warranted to investigate the toxicity and detailed mechanism of action of this potent compound before any clinical trials, especially at the effective lower doses.

Animals↗
PubMed2000

Inhibition of gastric mucosal damage by methylglyoxal pretreatment in rats.

The effect of methylglyoxal pretreatment on gastric mucosal injuries caused by 80% ethanol, 25% NaCl and 0.2 M NaOH, was investigated in rats. The effects caused by pylorous ligation accumulated gastric acid secretions and ethanol-induced changes in gastric mucus secretions, levels of proteins, nucleic acid, malondialdehyde (MDA) and non-protein sulfhydryl groups were also investigated. Methylglyoxal pretreatment at oral doses of 50, 100 and 200 mg/kg body weight was found to provide a dose-dependent protection against the ulcerogenic effects of different necrotizing agents used. With the same dose regimen methylglyoxal offered significant protection against ethanol-induced damage on the parameters evaluated for histopathology. Furthermore, the pretreatment afforded a dose-dependent inhibition of pylorous ligated accumulation of gastric acid secretions and ethanol-induced depletion of stomach wall mucus, proteins, nucleic acids, NP-SH contents and an increase in the MDA levels in gastric tissue. The protective effect of methylglyoxal against ethanol-induced damage to the gastric wall mucosa may be mediated through its effect on mucous production, proteins, nucleic acids, NP-SH groups and its free-radical scavenging property under the influence of polyamines stimulated by ornithine decarboxylase activity (ODC).

Animals↗
PubMed2000

A European multicentric experience using the CardioSEal and Starflex double umbrella devices to close interatrial communications holes within the oval fossa.

In this review, we describe the experience from 13 European centres using the CardioSEAL and Starflex double umbrella devices to close interatrial communications within the oval fossa (so-called 'secundum' defects). Between October 1996 and April 1999, the procedure was attempted in 334 patients with a mean age of 12 years and a mean weight of 44kg. The mean measured stretched diameter of the defect was 15 mm. In the overall group, the defect was solitary in 245 patients (73%), multiple in 21 (6%), associated with an aneurysm of the flap valve in 15 (5 %), was represented by patency of the oval foramen in 44 (13%), and was a fenestration in a Fontan repair in 9 (3%). In all patients, the devices were inserted under general anesthesia, using fluoroscopic and transesophageal echocardiographic control. Implantation was achieved in 325 (97,3%). The device embolized within either a few minutes or a few hours in 13 patients (4%). Of these, uncomplicated surgical repair was undertaken in 10, while the device was retrieved in 3 using catheters and a second device was successfully implanted. Residual shunting was detected immediately after the procedure in 41% of the patients, with the incidence decreasing to 31% at discharge, 24% at 1 month, 21% at 6 months, and 20.5% at one year. During the period of follow-up, elective surgical repair became necessary in two patients, due to malposition of the device in one, and late embolization in the other. Fractures of arms were seen in 6.1 %, most commonly with the largest devices. All those with fractured arms of the device were asymptomatic, and no clinical complications related to the fractures were observed. There were no arrhythmias, endocarditis, valvar distortion, thromboembolic events, or other complications. After one year of follow-up, clinical success, defined as complete closure of the defect or presence of only a trivial leak, had been obtained in 92.5% of the patients. We conclude, therefore, that these devices produce excellent results when used to close defects of small to moderate size. Results are less than optimal, or else complications ensure, when attempts are made to close very large defects.

Adolescent↗
PubMed2000

Studies on the cytotoxic, biochemical and anti-carcinogenic potentials of ninhydrin on Ehrlich ascites carcinoma cell-bearing Swiss albino mice.

Ninhydrin (2,2-dihydroxy-1,3-indane dione) was evaluated for its antitumor and cytotoxic properties in Ehrlich ascites carcinoma cell (EAC Cell)-bearing mice. The rationale behind this study has been mainly the literature reports of its characteristic interference with DNA synthesis and calcium homeostasis. Antitumor activity was evaluated from the total count and viability of EAC cells in addition to their nucleic acid, protein, non-protein sulfhydryls (NP-SH) and malondialdehyde (MDA) contents. The EAC cell-bearing animals were also observed for the effect on their survival and body weight variations. In addition, the tumors grown at the site of injection were evaluated for histopathological changes. Ninhydrin treatments (5, 10 and 20 mg/kg/day) abate the increase in body weight and advanced the duration of survival in EAC cell-bearing mice. The results on histopathological investigations show retardation in tumor growth, decreased frequency of mitotic figures and hair follicles and an increased necrosis in the tumor by ninhydrin treatment. Our results on cytotoxicity, which demonstrated compression in the number of EAC cells and their viability substantiate these data. The results of biochemical studies on EAC cells exhibit a reduction in the levels of DNA, RNA, proteins and NP-SH with a subsequent increase in the concentrations of MDA after ninhydrin treatment. Inhibition in tumor growth was dose dependently significant with the same dose regimen. The observed cytotoxic and antitumor activity of ninhydrin was comparable to cyclophosphamide. The possible mode of action of ninhydrin-induced cytotoxic and antitumor activity appear to be due to its interference with mitochondrial function resulting in inhibition of DNA synthesis, an effect that is being investigated further.

Animals↗
PubMed2000

Pathomorphological changes in mouse liver and kidney during prolonged valproate administration.

Mice given sodium valproate 0.71% weight/volume in drinking water for 7, 14 and 21 days were assessed for pathomorphological changes in liver and kidney tissues at certain time points. This treatment caused a marked alteration in liver and kidney cell morphology, which was proportional to the period of treatment. This treatment induced fatty degeneration of hepatocytes, increased the number of Kupffer cells and caused them to swell. These changes were irregular after days 7 and 14 of treatment but with time increased in intensity, producing inflammation of the portal tracts, albuminous degeneration and necrosis of septa. Precirrhotic conditions, cirrhosis, acidophilic degeneration of hepatocytes and glassy eosinophilic homogenous cytoplasm were a constant feature after 21 days' treatment. In some cases the portal area was invaded by small, round inflammatory cells. Hepatocytes in this group were swollen, with large nuclei and increased amounts of condensed chromatin. The kidney sections of the same animals revealed severe morphological changes, indicated by significant epithelial necrosis and sloughing of tubules, as well as cast formation and mild lymphocytic infiltrate after 21 days' treatment. The results suggest that the histopathologic changes induced by sodium valproate are dependent upon the duration of exposure of these organs to the drug. Prolonged use of this drug should be carefully assessed.

Animals↗
PubMed2000

The effect of carbonated beverages on colorimetric end-tidal CO(2) determination

Esophageal intubation is a significant complication of attempted airway control. Colorimetric end-tidal CO(2) monitors are highly sensitive and specific for detecting the presence of CO(2). There are reports of false-positive end-tidal CO(2) readings from esophageal intubations in patients who had ingested carbonated beverages. OBJECTIVE: To determine whether carbonated gastric contents can affect colorimetric end-tidal CO(2) readings. METHODS: End-tidal CO(2) was measured in sacrificed piglets at measured time intervals after instillation of 5-, 10-, 15-, and 20-mL aliquots of Diet Coke were placed into the stomach via a 28-French orogastric tube followed by esophageal intubation. The stomach was completely evacuated prior to each instillation and rechecked for baseline CO(2). RESULTS: Compiled data from three piglets (20-30 kg). Piglets were not ventilated or moved and determinations were measured at 20 degrees while supine. All data collected within 2 hours postmortem (table 24-1). CONCLUSIONS: The colorimetric end-tidal CO(2) turned "yellow" and did not change to blue with extended insufflations. The CO(2) of a small quantity of carbonated beverage in the stomach could be "blown off" by multiple insufflations. We conclude that esophageal intubation in the setting of recent ingestion of a carbonated beverage may result in a false-positive end-tidal CO(2) determination.

Journal Article↗