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T Mahmood

Publications and source records attributed to T Mahmood.

At least 37 records · Page 2Linked to original sources
PubMed2001

The effect of cAMP on ion transport in Fallopian tube epithelial cells in vitro.

The coupled movement of ions and water across epithelia determines the composition and volume of fluid present in the lumen of organs. The second messenger cAMP is important in effecting electrolyte and water transport in many transporting epithelia; however, its role in Fallopian tube transport is uncertain. We have conducted electrophysiological studies on Fallopian tube epithelial cell monolayers in Ussing chambers and have demonstrated that exogenously added cAMP and agents that generate its intracellular production results in an increase in short-circuit current consistent with the transport of net electrical charge from a basal to mucosal direction. In contrast to the known effects of ATP in this tissue, the increase in short-circuit current was not explicable in terms of electrogenic chloride secretion as it was not affected by the chloride channel inhibitors, 4-acetamido-4'-isothiocyanostilbene-2,2-disulphonic acid 1 mmol/l (SITS) and frusemide. Instead the current was reduced by the sodium channel inhibitor, amiloride, and was therefore, in part, explicable in terms of electrogenic Na+ absorption. These findings will enhance our understanding of the physiological mechanisms responsible for human Fallopian tubal fluid formation and composition.

Adenosine Triphosphate↗
PubMed2001

Ultrasonographic appearance of Ascaris lumbricoides in the small bowel.

Roundworm infestation, one of the most common helminthic diseases worldwide, is caused by Ascaris lumbricoides, one of the largest parasites that infests the human bowel. A lumbricoides is virtually universal at some stage of childhood in semitropical and tropical regions. This study describes our experience with the ultrasonographic appearance of intestinal ascariasis in 84 patients, 2.5 to 42 years of age, examined over 2 years beginning October 1997. The patients' conditions ranged from acute intestinal obstruction to no clinical features pertaining to obstruction. Ultrasonographic examination was performed with an Echocee power Doppler real-time unit with a variable-frequency 3.7-MHz convex, 7.5-MHz linear probe. In longitudinal section the Ascaris worm presented as a linear intraluminal mass with 3 or 4 linear echogenic interfaces; in the cross section, it was round, sometimes appearing as a "target" sign. Some worms also showed serpentine movements. Sonographic examination of the patients in the left lateral decubitus position after ingestion of water improved detection and visualization of the worms in some cases. It is concluded that A lumbricoides in the small bowel has a sonographic appearance that can be recognized by the wary observer.

Adolescent↗
PubMed2000

Angiotensin II in human seminal fluid.

The renin-angiotensin system (RAS) and angiotensin II are important in sperm function and male fertility. Angiotensin II type I (AT1) receptors have been identified in developing and ejaculated human spermatozoa, and angiotensin can stimulate sperm motility, the acrosome reaction and binding to the zona pellucida. However, there is little information on the availability of the hormone to spermatozoa during the reproductive process. Seminal plasma and blood plasma obtained from normal and subfertile subjects was extracted, and angiotensin content was analysed by radioimmunoassay. Values obtained for blood angiotensin II were within the normal range at 16.0 +/- 3.1 pg/ml (mean +/- SEM). Values for seminal plasma were usually 3-5 fold higher, at 51.6 +/- 9.3 pg/ml (n = 34, P < 0.0001). High performance liquid chromatography analysis showed that approximately 80% of the immunoreactive angiotensin was attributable to angiotensin II itself. However, seminal plasma angiotensin II concentrations were not correlated with blood angiotensin II, sperm concentration or sperm motility. The results show that immunoreactive angiotensin from a source other than the circulation is available to spermatozoa in human ejaculates. The results are consistent with the concept that angiotensin II has an important role in male fertility.

Angiotensin II↗
PubMed1999

Comparison of the growth patterns and morphological characteristics of mechanically and enzymatically isolated fallopian tube epithelial cells.

This study set out to compare the growth patterns and morphological characteristics of human fallopian tube epithelial cells isolated: (1) mechanically; and (2) enzymatically. Cells were cultured in medium supplemented with fetal bovine serum and antibiotics and their epithelial nature was established by immunocytochemistry for cytokeratins. Primary cultures were polygonal in shape with centrally located nuclei, irrespective of the isolation method. Cells isolated enzymatically exhibited a higher growth rate, but the survival rate was poor after more than 2-3 passages. Mechanical isolation gave a lower yield of cells, but had a higher survival rate when sub-cultured, even beyond 8 passages. Thus, mechanically isolated cells might be useful for longer term cultures, whereas enzymatically isolated cells are best only for short-term work.

Adult↗
PubMed1999

Axial flow fields in cuffed end-to-side anastomoses: effect of angle and disease progression.

OBJECTIVE: to visualise the axial flow fields in standard and cuffed end-to-side anastomoses (ESA). DESIGN: in vitro experiments using a flow rig, custom-built glass models and frame-by-frame video analysis of flow patterns in standard and cuffed ESA. SUBJECTS: glass models of standard or cuffed (1 cm or 2 cm high) ESA of angles 15, 30, 45 and 60 degrees. RESULTS: the cross-sectional area of standard ESA is much smaller than that of ESA between graft and cuff. The size of the vortex in the anastomotic zone of both standard and cuffed ESA increased with increasing ESA angle and cuff height, but did not change with flow rate. The presence of the vortex maintains a zone of flow separation and low shear at the heel of standard and graft/cuff anastomoses. CONCLUSIONS: the observations explain the clinical findings of intimal hyperplasia (IH) at the heel of PTFE/cuff anastomoses. The improved patency rates of cuffed ESA may be due not to decreased IH, but to an increased ability of the cuff to accommodate IH before causing a significant stenosis.

Anastomosis, Surgical↗
PubMed1999

Carcinoid syndrome with unknown primary: a case report.

Carcinoid syndrome usually is associated with a classic presentation, the diagnosis of which is supported by elevations in neuroendocrine substances such as 5-hydroxyindoleacetic acid and by localization and pathologic identification of a neuroendocrine tumor. The authors report a patient for whom there was a 7-year delay in diagnosis and even then a primary tumor could not be localized.

5-Hydroxytryptophan↗
PubMed1999

Lymphocytic venulitis: an unusual association with microscopic colitis.

A 79 year old man presented with occult gastrointestinal bleeds and anaemia for two years. He had received 40 units of blood over a period of one year, following which he had a subtotal colectomy as no definite cause of the bleeding was apparent. Macroscopically the colon appeared unremarkable. Light microscopy showed prominent lymphocytic venulitis in the proximal portion, gradually merging into lymphocytic and collagenous colitis distally.

Aged↗
PubMed1998

Comparison of POSSUM and the Portsmouth predictor equation for predicting death following vascular surgery.

BACKGROUND: The Physiological and Operative Severity Score for enUmeration of Mortality and morbidity (POSSUM) scoring system has been proposed as an accurate predictor of death which takes account of case mix. It appears to overpredict death, and may have drawbacks which prevent accurate individual or subgroup analysis. An alternative system, the Portsmouth predictor equation for mortality (P-POSSUM) may have overcome these problems, but its apparent advantage could be related to inappropriate analysis of POSSUM predictions. METHODS: Some 312 patients having arterial procedures were studied. POSSUM and P-POSSUM scores were used to predict death and compared with actual outcomes. The observed:predicted (O:E) mortality ratios were calculated by two methods for each of the scoring systems. First the analysis devised by the inventors of POSSUM was used and second the method devised for P-POSSUM. RESULTS: The O:E ratio for POSSUM using its recommended 'exponential' method of analysis was 1.14, but it was 0.59 if the P-POSSUM 'linear' analysis was used. The O:E ratio for P-POSSUM using its correct method of analysis was 0.89, but it was 0.67 if the method of analysis devised for POSSUM was used. CONCLUSION: The O:E ratios for POSSUM and P-POSSUM were close to unity when the appropriate analysis was performed. Both POSSUM and P-POSSUM overpredicted death if the incorrect analysis was used.

Aged↗
PubMed1998

The effect of ovarian steroids on epithelial ciliary beat frequency in the human Fallopian tube.

Using a method that detects variations in light intensity we have studied the effect of ovarian steroids on human Fallopian tube epithelial ciliary beat frequency in vitro. We have found that baseline ciliary beat frequency averages between 5-6 Hz. Cilia from ampullary segments of the Fallopian tube beat significantly faster (5.4 Hz+/-0.2) than those from fimbrial segments (4.8 Hz+/-0.2). There was no significant difference in baseline ciliary beat frequency at any other anatomical site in the Fallopian tube. Incubation with progesterone (10 micromol/l) suppresses human Fallopian tube epithelial ciliary beat frequency by 40-50%. This inhibition was observed at similar magnitudes in all Fallopian tubes studied irrespective of anatomical site. Progesterone-induced reductions in ciliary beat frequency were concentration dependent and prevented by the progesterone receptor antagonist mifepristone (RU486). Oestradiol alone (10 micromol/l) had no effect on ciliary beat frequency at any anatomical site in the Fallopian tube but did prevent the reduction in ciliary beat frequency seen with progesterone when tissues were incubated with these two steroids together.

Cilia↗
PubMed1997

Audit of infective morbidity following caesarean section at a district general hospital.

This paper sets out to audit infectious morbidity before and after introduction of a policy of antibiotic prophylaxis following emergency and elective caesarean section in a district general hospital in Scotland with approximately 3800 deliveries a year. In the first 'loop of audit', case notes of 200 consecutive patients managed during 1992 were studied. Audit loop was completed by studying 224 patients prospectively in 1993-94 following the introduction of new guidelines, which required the intraoperative administration of a single dose of intravenous antibiotic, following delivery of the baby. A significantly greater proportion of women received prophylactic antibiotics in 1993 compared with 1992 (81% vs. 14%; Diff= 67%; 95% CI 60%, 74%). The incidence of infection related morbidity was significantly reduced after routine antibiotic prophylaxis (28,5% vs. 16%; Diff= 12.5%, 95% CI=(4.60%,20.4%). The incidence of wound infection was halved in 1993 (9% vs. 17.5% in 1992). None of the patients in 1993 had a serious postoperative infection. Postnatal stay was significantly shorter in 1993 compared with 1992 (P < 0.0001). Although the target of adherence to the guidelines of 90% coverage was not met, this audit demonstrates the benefits of antibiotic prophylaxis for emergency and elective caesarean sections. Further reduction in morbidity may be obtained by strictly implementing the guidelines, and also by considering the use of multiple doses of antibiotics.

Journal Article↗
PubMed1997

Three successive pregnancies in a patient with Takayasu's arteritis.

Takayasu's arteritis is a rare non-specific obliterative panarteritis of unknown origin that occurs predominantly in young Asian and Oriental females of childbearing age and has been encountered in the UK. With the exception of a few large series from the Far East, much of the information on Takayasu's arteritis in pregnancy comes from isolated case reports with no long term follow-up after pregnancy. We report a patient with this condition who had three pregnancies during a 4-year follow-up period with no serious complications.

Journal Article↗
PubMed1997

Clozapine in the management of bipolar and schizoaffective manic episodes resistant to standard treatment.

OBJECTIVE: To test the efficacy of clozapine in treatment-resistant manic episodes. CLINICAL PICTURE: Three cases, two with bipolar disorder (manic) and one of schizoaffective disorder (manic), were treated with clozapine. TREATMENT: Clozapine was used after the failure of standard antipsychotics and mood stabilizers. OUTCOME: All three cases were successfully treated. CONCLUSION: A controlled trial of clozapine in treatment-resistant bipolar and schizoaffective manic episodes is indicated.

Adult↗
PubMed1996

Risperidone appears safe in patients with antipsychotic-induced blood dyscrasias.

Two cases are reported who developed blood dyscrasias, involving neutropenia and thrombocytopenia respectively, after treatment with phenothiazine and butyrophenone antipsychotics. A subsequent good therapeutic response was obtained with risperidone. It is suggested that risperidone may be considered as an alternative when blood dyscrasias occur with classic antipsychotics.

Adult↗
PubMed1996

Detection of fetal fibronectin as a predictor of preterm delivery in high risk asymptomatic pregnancies.

OBJECTIVE: The study was designed to determine whether fetal fibronectin would predict delivery before 37 weeks in women at high risk of preterm delivery. STUDY METHODS: Forty-three women considered at risk of preterm delivery were recruited antenatally into a blind longitudinal study. Quantitative assays of fetal fibronectin were obtained from sequential high vaginal swabs taken fortnightly from 24 to 34 weeks of gestation. Fibronectin concentrations of 0.05 microgram/ml or more were considered as positive. RESULTS: Results were calculated by swab and by subject. The sensitivity of an individual fibronectin swab in predicting preterm delivery within 14 days of testing was 71% and the specificity was 93%. The overall positive predictive value was 31% and the negative predictive value was 99%. The sensitivity of the fibronectin swab in predicting delivery before 37 weeks was 17% and the specificity was 93%. The positive predictive value was 50% and the negative predictive value was 73%. For a woman who has had a positive swab the sensitivity in predicting preterm delivery within 14 days of testing was 80% and the specificity was 83%; a woman was counted as positive only if the final swab was positive and preceded delivery by not more than 14 days. The positive predictive value was 36% and the negative predictive value was 97%. For a woman who has had a positive swab the sensitivity in predicting delivery before 37 weeks was 54%. The specificity, the positive predictive value and the negative predictive value were 85%, 64% and 79%, respectively. Women were counted as positive if any swab in the sampling sequence was positive. Fibronectin swabbing when calculated by patient did predict preterm delivery within 14 days of testing (P=0.01) and before 37 weeks (P=0.01). Analysis of the accuracy of predicting delivery from 7 to 28 days after sampling revealed that the best prediction for delivery was within the following 14 days. CONCLUSION: Serial fetal fibronectin assessment from 24 to 34 weeks of gestation anticipated preterm delivery within 14 days of testing and before 37 weeks for high risk asymptomatic women. Such testing should be performed every two weeks.

Adult↗