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Biomedical subjects

P Abraham

Publications and source records attributed to P Abraham.

At least 109 records · Page 6Linked to original sources
PubMed1998

Ankle-brachial index after maximum exercise in treadmill and cycle ergometers in athletes.

Previous works have focused on the normal ankle and arm pressure response to maximum bicycle exercise or moderate walking tests. The aim of the present work was to compare the normal ankle and arm pressure and ankle-brachial index response to incremental maximum bicycle and treadmill exercise in 13 athletes (11 men, two women, 24 +/- 11 years) No difference was found at rest on both ankle pressure 139 +/- 21 vs. 163 +/- 22 mmHg and ankle-brachial index 1.18 +/- 0.09 vs. 1.17 +/- 0.10 between bicycle and treadmill tests respectively (mean +/- SD). One minute after maximum exercise, no difference in arm pressure was found between bicycle (182 +/- 16 mmHg) and treadmill tests (190 +/- 17 mmHg), whereas ankle pressure was 139 +/- 21 vs. 163 +/- 22 mmHg respectively (P < 0.05). As a result, a significant difference was found in the ankle-brachial index 0.76 +/- 0.10 vs. 0.86 +/- 0.10 (P < 0.05) between bicycle and treadmill ergometers during the first minute of the recovery period. Although performed at comparable workloads, a significant difference was noted between running and cycling tests. Thereby, the limit cut-off point for the diagnosis of lower extremity arterial disease in athletes defined for maximum bicycle tests may not apply to maximum incremental treadmill tests.

Adolescent↗
PubMed1998

Laser Doppler flowmetry in the diagnosis of chronic compartment syndrome.

Chronic compartment syndrome (CCS) is usually considered to be due to ischaemia of muscle. We have attempted to use the direct measurement of muscle blood flow for diagnosis since the assessment of intracompartmental pressure does not provide accurate knowledge of the vascular state. We recorded simultaneously continuous measurements of the laser Doppler flow (LDF) in muscle and the intracompartment pressure (ICP) after exercise in seven patients with CCS, and in seven control subjects. The mean ICP was 74.1 +/- 4.4 mmHg in CCS patients and 24.2 +/- 3.4 mmHg in control subjects one minute after exercise, decreasing to 34.6 +/- 2.3 mmHg and 15.0 +/- 1.6 mmHg at 20 min, respectively. The LDF was 0.80 +/- 0.11 arbitrary units (AU) in control subjects and 1.09 +/- 0.14 AU in CCS patients one minute after exercise, and 0.41 +/- 0.11 AU and 0.27 +/- 0.04 AU, respectively, at the end of the recovery period. The ICP showed a progressive decrease over time in both groups. The LDF decreased sharply during the first minutes of recovery in control subjects, but in patients with CCS there was a delayed hyperaemic peak with blood flow reaching 0.84 +/- 0.10 AU at nine minutes as against 0.33 +/- 0.06 AU for control subjects (p < 0.01). The ICP increased in both control subjects and CCS patients after exercise with no clear cut-off point between the groups. By contrast, changes in muscle blood flow over time were clearly different between control subjects and patients with CCS. For this reason, LDF should be investigated further as a technique for the diagnosis of CCS.

Chronic Disease↗
PubMed1998

Consumption of 'country liquor' and its relation to alcoholic liver disease in Mumbai.

The amount of alcohol intake required for the development of liver disease has been determined in Western populations; corresponding figures in Indians, many of whom consume locally brewed liquors, are not known. We studied 328 patients from a public hospital in Mumbai who admitted to regular alcohol consumption, to determine the pattern of alcohol consumption and its relation to liver disease. Liver disease was more common in those who consumed illicitly-brewed as compared to licit liquor. Daily drinking, volume of consumption > 200 ml per day, and duration of drinking > 14 years were each significantly more common in those with liver disease. A cumulative intake of > 2000 ml. years, calculated as the product of volume (ml per day) and duration (years), was a reliable cut-off level for association with liver disease (sensitivity 65%, specificity 77%) and cirrhosis (sensitivity 70%, specificity 59%). The content of alcohol in these liquors, estimated in 23 samples, ranged from 23-36.1 g/100 ml, being lower in the illicit liquors. Thus, in Mumbai, alcoholic liver disease occurs more commonly with consumption of illicit liquor (despite its lower alcohol content); liver involvement appears earlier and with lower consumption levels than in the West.

Adult↗
PubMed1998

Vagal dysfunction following endoscopic variceal sclerotherapy.

BACKGROUND: Sclerotherapy is associated with complications which involve adjacent structures like the pleura. The effect of sclerotherapy on function of the vagus nerve, which lies in close proximity to the thoracic esophagus, is not clear. AIM: To study gastric acid secretion as a marker of vagal function in portal hypertensive patients who have undergone sclerotherapy. METHODS: Portal hypertensive patients who had undergone at least three sessions of sclerotherapy were evaluated by mapping gastric acid-secreting mucosa by the Congo red test and by estimating gastric acid secretion using the modified sham feeding test. Patients with portal hypertension who had never been subjected to endoscopic sclerotherapy were recruited as controls. RESULTS: On Congo red test, complete or substantial reduction in acid-secreting mucosa was observed in eight patients in comparison to none of the controls. Significantly lower acid secretion on modified sham feeding test was observed in these eight patients. CONCLUSION: A lower gastric acid secretion, probably secondary to vagal dysfunction, is seen in patients who have undergone multiple sessions of sclerotherapy; vagus nerve involvement may be secondary to periesophageal inflammation.

Adult↗
PubMed1998

Manometric mapping of normal esophagus and definition of the transition zone.

BACKGROUND: The normal esophagus has not been manometrically mapped. The transition zone between esophageal smooth and skeletal muscles has also not been defined manometrically. AIMS: To manometrically map the normal esophagus and to define the transition zone. METHODS: Thirty normal adults [23 men; mean age 34.8 (10.4) years] underwent manometry using a water-perfused system. The lower esophageal sphincter (LES) was studied by station pull-through, and esophageal body musculature was evaluated at 1-cm intervals with five wet swallows at each level. The transition zone was identified as an area where the wave-forms did not resemble typical skeletal or smooth muscle wave-forms. RESULTS: The basal mid-expiratory LES pressure was 18.7 (7.2) mmHg, and its length was 3.6 (1.2) cm. Based on our findings, we defined the transition zone as an area where either the amplitude of contraction was < 40 mmHg or, if the amplitude was 40-50 mmHg, the rate of change of pressure from baseline to peak of the wave was < 50 mmHg/s. The lengths of the skeletal, transition and smooth muscle zones were 2.8 (1.2), 4.0 (1.7) and 12.5 (2.7) cm, respectively. The amplitude and dp/dt of contraction and transmission velocity were lowest in the transition zone (p < 0.05). CONCLUSIONS: We have manometrically mapped the normal esophageal muscle zones; the parameters obtained may be used as reference values. The manometric criteria for the transition zone have also been defined.

Adult↗
PubMed1997

Synthesis and transporter binding properties of 2,3-diphenyltropane stereoisomers. Comparison to 3beta-phenyltropane-2beta-carboxylic acid esters.

2beta,3beta-Diphenyl-(5), 2alpha,3alpha-diphenyl-(6), and 2alpha,3beta-diphenyltropane (3) as well as 2,3-diphenyltrop-2-ene (4) were prepared in racemic form and assayed for inhibition of radioligand binding at the dopamine (DA), serotonin (5-HT), and norepinephrine (NE) transporters. Among all three transporters, compounds 4-6 bound the DA transporter with the highest affinity. The 2beta,3beta-diphenyltropane (5) bound the DA transporter with an IC50 value (28 nM) almost identical to that of 3beta-phenyltropane-2beta-carboxylic acid methyl ester (WIN 35,065-2) and has much greater selectivity relative to binding to the serotonin transporter. A comparison of the radioligand data from this study to radioligand data obtained on other WIN 35,065-2 analogs suggests that hydrophobicity of the C-2 substituent of some analogs of the WIN 35,065-2 class may be an important contributing factor to binding at the DA transporter.

Binding, Competitive↗
PubMed1997

N-substituted phenyltropanes as in vivo binding ligands for rapid imaging studies of the dopamine transporter.

Variously substituted phenyltropanes are proven as superb binding ligands for the dopamine transporter (DAT). In this study, we examine four N-substituted phenyltropanes which are derivatives of RTI-55 as in vivo binding ligands in mice. In this series, the methyl group on the nitrogen was replaced by a propyl (RTI-310), an allyl (RTI-311), a butyl (RTI-312), or a fluoropropyl (RTI-313) group. The in vitro binding potencies of these compounds at rat striatal DAT varied somewhat but were about 1 nM. While these compounds did not display marked selectivity for the dopamine transporter, they were more selective than RTI-55. Injection of the radiolabeled compound into mice resulted in striatal-to-cerebellar ratios that varied from about 4.5-6.5. The ratios peaked most rapidly for RTI-311 and RTI-313, at about 20 min. Pharmacological inhibition studies indicated that these compounds were binding to DATs in the striatum, as expected. These findings suggest that some compounds of this type may be excellent in vivo binding ligands for rapid imaging studies of the DAT.

Analysis of Variance↗
PubMed1997

Effects of positive pressure on both femoral venous and arterial blood velocities and the cutaneous microcirculation of the forefoot.

OBJECTIVE: The balance between the apparent beneficial effect and the risk of arterial ischaemia resulting from an external uniform compression is unclear. The purpose of this study was to determine the effects of a positive uniform compression on the lower limb circulation until a critical threshold was reached. METHODS: We used Doppler ultrasound to measure femoral venous and arterial blood velocities. The effects of positive pressure on cutaneous microcirculation were evaluated by laser Doppler flux (LDF), transcutaneous oxygen pressure (tcpO2) and transcutaneous carbon dioxide pressure (tcpCO2) on the forefoot of 17 healthy subjects. RESULTS: The results are expressed as median [lowest observed value-highest observed value]. Whereas the arterial femoral velocity (A.F.V.) decreased from 0.21 [0.08-0.36] to 0.17 [0.08-0.28] m s-1 for an external pressure as low as 10 mmHg (p < 0.001), the venous femoral velocity (V.F.V.) decreased from 0.13 [0.06-0.40] to 0.09 [0.05-0.34] m s-1 at 20 mmHg (p < 0.001). An increase of tcpCO2 from 39.8 [29.9-53.7] to 40.2 [30.0-55.5] mmHg (p < 0.05) and a decrease of LDF from 8.7 [3.1-25.9] to 5.5 [2.3-21.1] A.U. (p < 0.001) occurred at 10 mmHg. However, tcpO2 decreased only from 76.7 [40.2-91.2] to 64.6 [18.9-85.2] mmHg when the splint pressure reached 60 mmHg (p < 0.05). The observed parameters (LDF, tcpO2, V.F.V. and A.F.V.) decreased further (except for tcpCO2 which increased) up to the end of the study as the applied pressure was increased. CONCLUSION: Positive pressure on the full leg provided no significant beneficial effect on femoral venous blood velocity. Whereas we showed that for an external uniform pressure as low as 10 mmHg, significant impairments in both arterial inflow of the lower limb and microcirculation of the forefoot appeared in recumbent healthy young subjects.

Adult↗
PubMed1997

Prolonged asymptomatic micro-embolism after hip or knee arthroplasty.

We studied the time course of micro-embolism by recording high intensity transient signals (HITS) on Doppler venous blood flow studies during a 7-day period in 57 of 63 consecutive patients after hip or knee replacement. No HITS were found before surgery, or in the non-operated leg after surgery. In the operated leg, the median number of HITS per minute showed an exponential decrease with time; a 50% reduction in the number of HITS took 72 minutes. Regardless of the duration and severity of HITS, we found no clinically apparent embolic event. Colour Doppler imaging at days 8 to 10 after operation showed a deep venous thrombosis in 17% of our patients with one thrombosis of the long saphenous vein. The presence or severity of HITS did not predict the venous thrombi. Although we found no pulmonary complications, we detected micro-emboli over a longer period after surgery than is usually reported. Spectral analysis of the Doppler venous signal is a repeatable and non-invasive monitoring technique in the post-surgical period. We failed to prove a correlation between deep venous thrombi and micro-emboli detected by this method.

Aged↗
PubMed1997

External iliac artery endofibrosis in athletes.

Atherosclerosis and inflammatory arterial diseases are rare in young people. Since the early 1980s, an increasing incidence of iliac arterial stenosis in competition cyclists has been reported. Histological findings in these individuals are specific, with fibrosis of the intimal wall on histology and no atherosclerotic or inflammatory lesions. Clinical consequences of this arterial endofibrosis are usually described as an exercise-related subjective sensation of swollen thigh in one or both (15%) legs, with normal clinical and Doppler investigations at rest. Following maximal exercise, ankle-to-brachial systolic pressure index is lower than 0.5 in 85% of individuals with disease and is used as a key argument for diagnosis before deciding upon arteriography. Surgery (recalibrated saphenous grafts or angioplasty-endofibrosectomy) seems to be efficient to allow an early return to competition, but its long term results are still to be evaluated. The physiopathology of this disease and its possible relationship with atherosclerosis are unknown.

Adult↗
PubMed1997

[In situ thrombolysis in the treatment of venous thrombosis of effort in the arm].

From March 1989 to March 1993, six athletic patients were treated in our institution by thrombolytic therapy for acute effort axillary-subclavian vein thrombosis in thoracic outlet syndrome. Mean age of these patients was 20 (range 14 to 27). An in situ infusion with urokinase (2,500 U/kg/h) and Heparin (100 U/kg/12 hours) was given during 64 hours (Range 14 to 72). Phlebography showed a complete reperfusion in three cases (the treatment began within an average period of 5.6 days), partial reperfusion in two cases (the treatment began within an average period of 8.5 days). In one case there was no reperfusion on phlebography: treatment began within an average period of 15 days. For this patient, a venous axillo-jugular bypass graft was performed. In all cases, there was no bleeding complication. A trans-axillary first rib resection was done three months later. Mean follow up was 31 months (range: two to 51 months). All patients recovered their previous physical status. Echo-Doppler exam showed normal subclavian vein flow in four cases, partial occlusion in one case and a total occlusion of the subclavian vein flow in one case. In this last case, the thrombolytic therapy failed to restore the permeability of the subclavian vein. Bypassgraft was patent. Axillary-subclavian vein thrombosis seen within a period of seven days should be treated by local thrombolytic therapy using urokinase and heparin.

Acute Disease↗
PubMed1997

Metronidazole relieves symptoms in irritable bowel syndrome: the confusion with so-called 'chronic amebiasis'.

BACKGROUND: Metronidazole is often administered to patients with irritable bowel syndrome with an erroneous diagnosis of 'chronic amebiasis'. AIMS: To assess how patients with irritable bowel syndrome respond to metronidazole in the absence of amebae in their stools. METHODS: We randomly allocated 45 patients (35 men; aged 15-59 years) with irritable bowel syndrome to receive isapghul (10 g bid x 60 days), metronidazole (400 mg tid X 10 days, followed by placebo x 50 days), or placebo (1 capsule bid x 60 days). Symptoms were evaluated and scored on days 0, 15, 30, 45 and 60. Rectosigmoid manometry was performed in 5 of 15 patients in each group on days 0 and 60. RESULTS: There was a significant time effect and treatment effect on the symptom scores in all groups (isapghul > metronidazole > placebo); total score decreased from mean 25.8, 24.0 and 24.6 on day 0 to 7.2, 10.9 and 18.1 on day 60, respectively. Severity, duration and frequency of pain; and mucus in stool were all significantly reduced in all treatment groups (p < 0.001 for each). Treatment with isapghul increased the mean amplitude of propagated activity from 26.2 mmHg to 30.1 mmHg at 20 cm (p < 0.025) and from 23.1 mmHg to 27.4 mmHg at 10 cm (p < 0.05) from the anal verge, as well as the total duration of propagated activity at both sites (p < 0.05), with decrease in number of propagated contractions per 10 min (p < 0.025). Metronidazole and placebo had no effect on manometric findings. CONCLUSIONS: Metronidazole provides symptom relief in irritable bowel syndrome, without affecting rectosigmoid motility. This symptom response may be misinterpreted as supporting a diagnosis of 'chronic amebiasis'.

Abdominal Pain↗
PubMed1997

External iliac artery endofibrosis: a 40-year course.

External iliac artery endofibrosis is a rare disease affecting mainly highly trained cyclists. As the disease has only recently been described, the long term spontaneous evolution of external iliac artery endofibrosis is not known. We report a suspected case of forty-year spontaneous evolution of endofibrosis in a former competition cyclist. The results of this isolated original report suggest, as we intuitively presumed, that the lesions may stabilise when intensive training is stopped. Therefore, when no symptoms are noted on usual daily activity or submaximal exercise, surgery should not be performed. Surgery should only be considered, at the request of the subjects to allow them to continue competing.

Activities of Daily Living↗