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S Raju

Publications and source records attributed to S Raju.

At least 19 recordsLinked to original sources
PubMed2001

Analysis of CC chemokine and chemokine receptor expression in solid ovarian tumours.

To understand the chemokine network in a tissue, both chemokine and chemokine receptor expression should be studied. Human epithelial ovarian tumours express a range of chemokines but little is known about the expression and localisation of chemokine receptors. With the aim of understanding chemokine action in this cancer, we investigated receptors for CC-chemokines and their ligands in 25 biopsies of human ovarian cancer. CC-chemokine receptor mRNA was generally absent from solid tumours, the exception being CCR1 which was detected in samples from 75% of patients. CCR1 mRNA localised to macrophages and lymphocytes and there was a correlation between numbers of CD8(+) and CCR1 expressing cells (P = 0.031). mRNA for 6 CC-chemokines was expressed in a majority of tumour samples. In a monocytic cell line in vitro, we found that CCR1 mRNA expression was increased 5-fold by hypoxia. We suggest that the CC-chemokine network in ovarian cancer is controlled at the level of CC-chemokine receptors and this may account for the phenotypes of infiltrating cells found in these tumours. The leukocyte infiltrate may contribute to tumour growth and spread by providing growth survival factors and matrix metalloproteases. Thus, CCR1 may be a novel therapeutic target in ovarian cancer.

Adenocarcinoma, Clear Cell↗
PubMed2001

Reversal of abnormal lymphoscintigraphy after placement of venous stents for correction of associated venous obstruction.

PURPOSE: The purpose of this study was to report improvement or normalization of abnormal lymphoscintigraphy in swollen lower limbs after correction of associated venous stenosis by balloon dilatation and placement of venous stent of the iliac veins. MATERIAL: Twenty-six patients with lower-limb swelling underwent balloon dilatation and placement of venous stent of the iliac veins for correction of venous stenosis. Technetium 99M-sulfur colloid lymphoscintigraphy was also abnormal (8 absent, 18 reduced) before stent placement in all 26 limbs, suggesting combined venous/lymphatic etiology for the limb swelling. Median age was 53 years. Male-to-female ratio was 1:8 and left-to-right ratio, 3:1. Fifteen patients had limb pain associated with the swelling. Severity of venous stenosis was generally underestimated by preoperative transfemoral venography as compared with intravascular ultrasound, (mean, 50% versus 77%); in five limbs (19%), transfemoral venography altogether failed to identify the venous lesion evident on intravascular ultrasound. The etiology of venous obstruction was post-thrombotic in nine limbs and nonthrombotic (web, stricture, or May-Thurner syndrome) in 17 limbs. RESULTS: Poststent lymphoscintigraphy completely normalized in 10 limbs, improved but remained abnormal in 9, and remained unchanged in 7. Clinical follow-up (mean, 1 year) showed improvement in swelling in 16 of 26 limbs (P <.022), with complete resolution of swelling in six; degree of pain also improved (P <.02), with total relief of pain in 9 of 15 patients. There was also significant improvement in all categories of a quality of life questionnaire. CONCLUSION: These findings suggest that patients with a diagnosis of lymphedema made on the basis of lymphoscintigraphy alone and consigned to conservative therapy on that basis may benefit from additional venous investigations regardless of clinical presentation suggestive of lymphedema. This report supports the practice of aggressively searching for a venous basis of edema in these patients. Correction of the venous lesion may result in normalization or improvement of the lymphoscintigraphic abnormality and in any case may yield significant symptom relief, even in some limbs where the lymphoscintigraphic abnormality failed to improve after placement of venous stent.

Catheterization↗
PubMed2000

Venous valve station changes in "primary" and postthrombotic reflux: an analysis of 149 cases.

The purpose of this study was to analyze valve station changes noted during venous valve reconstruction and the associated outcome. One hundred and forty-nine valve reconstructions were available for analysis at the time of surgical exploration; the venous valve was graded according to valve station changes (VS grades) from zero through six. Ascending venography was analyzed by a similar grading system and the two methods were compared. The results of this analysis showed that valve station wall changes are frequently present in patients with deep venous reflux and pose technical challenges during valve reconstruction; the outcome, however, appears unaffected. Grade 0 to 1 valve station changes are predominantly due to "primary" reflux, with an occasional instance of postthrombotic etiology. Grade 2 or 3 valve station changes are roughly evenly divided between phlebosclerosis of primary reflux and postthrombotic etiologies. The mechanism of onset of reflux with preservation of valve cusps in the latter group of postthrombotic cases is probably different from currently accepted theories of evolution of postthrombotic changes. Postthrombotic valve damage is variable, and the valve station anatomy may be sufficiently preserved in some patients to allow direct valve repair.

Endothelium, Vascular↗
PubMed2000

Endovascular surgery in the treatment of chronic primary and post-thrombotic iliac vein obstruction.

OBJECTIVES: To compare the results and complications of endovascular surgery in limbs with post-thrombotic and non-thrombotic disease and to detail some technical aspects of the procedure. DESIGN: A single centre, prospective study. MATERIALS AND METHODS: Between March 1997 and August 1999, 139 consecutive lower extremities with chronic iliac venous obstruction (61 limbs with primary disease [MTS] and 78 with post-thrombotic disease [PTS]) were treated by balloon dilation and stenting. History, clinical examination, procedure and follow-up data were recorded. RESULTS: Mortality was zero. Non-thrombotic complication rate was only 3%. Postoperative (8%, 6/78) and late occlusion (3%, 2/69) occurred only in post-thrombotic limbs. Primary, primary-assisted and secondary cumulative patency rates of the stented area at 2 years were 52%, 88% and 90%, respectively, in the PTS group as compared to 60%, 100% and 100% in the MTS group. Clinical improvement in pain and swelling was significant in both groups. Half of active venous ulcers healed after the procedure. CONCLUSIONS: Chronic iliac vein obstruction appears to be a symptomatic lesion that can be treated safely and effectively by endovascular surgery regardless of aetiology. Generous use of IVUS is suggested in both diagnosis and treatment since phlebography is unreliable. The clinical improvement was significant in both groups; however, more excessive neointimal hyperplasia and a higher early and late occlusion rate were observed in post-thrombotic disease. Stenting after balloon dilation is advised in all venoplasties; stents should be inserted well into the IVC when treating iliocaval junction stenosis. A wide-diameter (16 mm) stent is recommended. The stent should cover the entire lesion as outlined by the IVUS.

Adolescent↗
PubMed2000

Popliteal vein entrapment: a benign venographic feature or a pathologic entity?

PURPOSE: Asymptomatic morphologic popliteal vein entrapment is frequently found in the healthy population (27%). In our institution, popliteal vein compression on plantar flexion was observed in 42% of all ascending venograms. Some authorities consider the lesion benign, without pathologic significance. This study examines the pathophysiologic importance in select patients, describes treatment with surgery, and suggests a diagnostic tool. METHOD: Thirty severely symptomatic patients with venographic evidence of popliteal entrapment were selected to have popliteal vein release after a process of elimination (ie, other causes of chronic venous insufficiency [CVI] were ruled out by means of comprehensive hemodynamic and morphologic studies). In the last nine limbs, popliteal vein pressure was also measured by means of the introduction of a 2F transducer tip catheter. Patients were clinically and hemodynamically assessed before and after surgery, and anatomical anomalies encountered during surgery were recorded. RESULTS: Popliteal vein release was performed without mortality or serious morbidity. Anomalies of the medial head of the gastrocnemius muscle caused entrapment in 60% of the patients; anatomic course venous anomalies were infrequent (7% of the patients). Significant relief of pain and swelling occurred in the patients who had surgery. Stasis ulceration/dermatitis resolved in 82% of patients. Popliteal venous pressures had normalized in the six patients who were studied postoperatively. CONCLUSION: Popliteal vein entrapment should be included in the differential diagnosis of CVI in patients in whom other, more common etiologies have been excluded on the basis of comprehensive investigations. Popliteal vein compression can be demonstrated venographically in a large proportion of patients with CVI, but the lesion is likely pathological only in a small fraction of these patients. A technique for popliteal venous pressure measurement is described; it shows promise as a test for functional assessment of entrapment. Immediate results of popliteal vein release surgery are encouraging; long-term follow-up is necessary to judge the efficacy of surgical lysis of entrapment in symptomatic patients who fail to improve with conservative treatment measures.

Adult↗
PubMed2000

Ambulatory venous pressure revisited.

PURPOSE: The purpose of this study was to describe a method for measuring the deep venous pressure changes in the lower extremity and compare it with those obtained in the dorsal foot vein. METHODS: After cannulation of the posterior tibial vein, a catheter with a pressure transducer in its tip was inserted and placed at the knee joint level. The dorsal foot vein was also cannulated. Pressures were recorded simultaneously at both sites during toe stands and repeated with the probe in the upper, middle, and lower calf. RESULTS: The study was performed in 45 patients with signs and symptoms of chronic venous insufficiency. Duplex Doppler scanning and ascending and descending venography performed before pressure measurements revealed saphenous vein incompetence in 11 lower extremities, incompetent perforators in 11 extremities (eight were combined with saphenous incompetence), and marked compression of popliteal vein with plantar flexion in 28 extremities. No significant deep axial reflux was observed on duplex Doppler examination or descending venography. No morphologic outflow obstruction was detected. The mean deep pressure at the knee joint level fell during toe stands, -15% +/- 27 (SD), and the mean dorsal foot vein pressure drop was even more marked, -75% +/- 22 (SD). Although the exercise pressure in the dorsal foot vein decreased in all patients (range, 13-90% drop), the popliteal vein pressure increased (4-72%) in nine limbs, decreased only marginally if at all in 15 limbs (0-15%), and fell more markedly in 21 extremities (22-65%). Deep vein recovery time was considerably shorter overall as compared with the findings by the dorsal vein measurement. In the comparison of limbs with and without superficial reflux, the recovery times in the deep system were significantly shorter in limbs with superficial incompetence. CONCLUSION: Ambulatory dorsal foot venous pressure is not always accurate in detecting changes in the pressure of the tibial and popliteal veins. Although dorsal foot venous pressure may be normal, deep venous pressure may decrease to a lesser degree or even increase.

Adult↗
PubMed2000

Differences in pressures of the popliteal, long saphenous, and dorsal foot veins.

PURPOSE: The purpose of this study was to examine the relationship among pressures obtained simultaneously in the popliteal, long saphenous, and dorsal foot veins. METHOD: Eight limbs were studied. One limb had an isolated popliteal vein reflux, and two had moderate long saphenous vein incompetence. No perforator or short saphenous vein insufficiency was detected. Pressures and recovery times of the popliteal/tibial and long saphenous veins were obtained with cannulation at the ankle level and insertion of catheters with a pressure transducer tip. The dorsal foot vein pressure was measured with the insertion of a scalp needle (14-gauge) connected to an external transducer. During 10 toe stands, recordings were simultaneously made in the three veins at the level of the knee joint, in the middle third of the calf, and 5 to 7 cm above the ankle with all the transducers at the same level (ie, same reference point). RESULTS: In one limb the popliteal/tibial pressure increased at all calf levels, whereas pressures decreased in both saphenous and dorsal foot veins. The pressures decreased in all three systems in the remaining seven limbs. There was no statistical difference between the pressure drop in the long saphenous vein and the deep vein. However, the decrease of the dorsal foot venous pressure was significantly more marked compared with the other two veins at all levels. The recovery time was significantly increased in the long saphenous vein compared with the deep vein; recovery time was further prolonged in the dorsal foot vein. CONCLUSION: The dorsal foot, long saphenous, and popliteal/posterior tibial veins clearly exhibit different pressure waveforms in response to calf exercise. The postexercise pressure, the percentage pressure drop, and the recovery times are widely different, which indicates that the three veins behave hydraulically as separate compartments in limbs without significant venous insufficiency.

Adult↗
PubMed2000

Transcommissural valvuloplasty: technique and results.

PURPOSE: The purpose of this study was to describe the technique of a variation of closed external venous valve repair (transcommissural valvuloplasty), its complication rate, and duplex scan durability. METHODS: The "blind" transcommissural valve repair of the vein was performed by placing transluminal sutures along the valve attachment lines, which simultaneously closed the valve attachment angle and also tightened the valve cusps. A total of 179 successfully repaired valve sites of 141 limbs in 129 patients were followed up 1 to 42 months through clinical observation and with duplex Doppler ultrasound scan. RESULTS: Postoperative complications (< 30 days) occurred in 12 (9%) of 141 limbs: superficial (1) and deep (1) wound infection, large wound hematoma (4), seroma (1), and deep vein thrombosis (5), with associated pulmonary embolus in one patient. Seventy-eight percent (reflux time </= 0.5 seconds) and 81% (reflux time </= 1.0 seconds) of valve sites were competent. The cumulative competency rate at 30 months was 59% and 63%, respectively. The cumulative ulcer recurrence-free interval was 63% at 30 months (n = 92). The pain score and swelling grade substantially improved. CONCLUSION: Transcommissural valvuloplasty is a safe procedure with low morbidity. It is relatively rapid and simple to perform, and its competency rates are comparable to those of internal valvuloplasty. Advantages over the internal repair are that venotomy is not required, repair can be extended to small-caliber veins, and multiple valve stations can be repaired in a single stage.

Adult↗
PubMed2000

Balloon dilation and stenting of chronic iliac vein obstruction: technical aspects and early clinical outcome.

PURPOSE: To describe the technical aspects of percutaneous balloon dilation and stenting for the treatment of venous outflow obstruction in chronic venous insufficiency. METHODS: Between March 1997 and December 1998, 94 consecutive patients (median age 48 years, range 14 to 80) with suspected iliac vein obstruction in 102 limbs were studied prospectively with the intent to treat any venous occlusion or stenosis verified during femoral vein cannulation. Data from the history, clinical examination, procedure, and follow-up were recorded. Preoperative indicators of obstruction were venographic evidence of occlusion, stenosis, or pelvic collateral vessels; increased arm-foot venous pressure differential; and abnormal hyperemia-induced venous pressure elevation. RESULTS: Cannulation and technical success rates were 98% and 97%, respectively, with 118 Wallstents deployed in 77 veins. Primary, assisted primary, and secondary patency rates at 1 year were 82%, 91%, and 92%, respectively. Clinical improvement in pain and swelling was significant. CONCLUSIONS: Stenting of benign iliac vein obstruction is a safe method with good short-term results. Venous lesions should always be stented; when treating iliocaval junction lesions, stents should be inserted well into the inferior vena cava. Absence of collateral vessels does not exclude the existence of significant obstruction, and their presence may indicate an obstruction not visualized. No gold standard for accurate pre- or intraoperative patient selection is currently available.

Adolescent↗
PubMed1999

A multicenter, phase I evaluation of cryopreserved venous valve allografts for the treatment of chronic deep venous insufficiency.

PURPOSE: A phase I feasibility study was conducted to determine whether cryopreserved venous valved segments would remain patent/competent in a short-term period (6 months). METHODS: The target group consisted of 10 patients (C(4-6), E, A(D), P(R)). The exclusion criteria included untreated superficial/perforator venous disease, significant venous or arterial obstruction, hypercoagulability or coagulopathy, and significant preexisting medical conditions. Required preoperative tests were venous duplex, ascending/descending venography, and a physiologic study (eg, APG, blood typing, an ankle/brachial index, and if post-thrombotic, a hypercoagulability work-up). A single-valve transplant was placed below all reflux, aided by anticoagulation with or without a distal arteriovenous fistula. Postoperative assessment included duplex scanning/clinical examination (at 1, 3, and 6 months), descending venogram (at 1 month), and physiologic study (at 1 and 6 months). The primary end point was valve patency/competence, with clinical outcome as a secondary end point. Adverse events were recorded. RESULTS: After eliminating protocol violations, nine patients with superficial femoral (5) or popliteal (4) vein valve transplants were studied. Six-month actuarial results show a patency rate of 67% +/- 16% and 78% +/- 13%, respectively, a primary and secondary competency rate of 56% +/- 17% and 67% +/- 16%, respectively, and a 100% patient survival rate. Clinical outcome averaged 1.1, with healing and/or freedom from ulcer recurrence, in six of nine patients. A postoperative risk of seroma formation (3) and cellulitis (1) exists. CONCLUSION: In patients with few remaining therapeutic options, one can achieve a 6-month assisted patency and competency rate of 78% and 67%, respectively, with an improved clinical outcome.

Actuarial Analysis↗
PubMed1999

Axillary vein transfer in trabeculated postthrombotic veins.

PURPOSE: This study assessed whether axillary vein transfer can be successfully performed in trabeculated veins and whether patients with this severe form of postthrombotic syndrome can be helped by an aggressive approach. METHODS: A total of 102 axillary vein transfer procedures were carried out in 83 limbs with trabeculated veins. More than one venous segment was repaired in 38 limbs with a second axillary valve in 19, and a different technique was used in the remainder. The superficial and deep femoral veins were the most common target sites. "Bench repair" of leaky axillary valves was performed before the transfer in 32 cases. Venous stasis dermatitis or ulceration was present in 90% of the limbs. The operability rate and chance of successful valve reconstruction was high, even in the presence of severe venographic appearance. RESULTS: The actuarial transplant patency rate was 83% at 10 years. The actuarial freedom from recurrent ulceration rate was more than 60% at 10 years, similar to the results obtained in a matched group of axillary vein transfers to nontrabeculated veins. Severe preoperative ambulatory venous hypertension (venous filling time [VFT] of less than 5 seconds), which was present in 67% of patients, did not adversely affect outcome, but short VFTs that persisted after surgery did. VFT and VFI90 (venous filling index, air plethysmography) improved after valve transfer. Swelling disappeared or was significantly reduced in 55% of patients (11 of 20 patients) who had moderate or severe preoperative swelling. In 82% of patients (31 of 37 patients) who had mild or no preoperative swelling, the swelling remained stable after surgery, and in 18% of patients (6 of 37 patients), it became worse. Pain was significantly diminished in 70% of patients; 23% of patients with severe pain had complete resolution. CONCLUSION: Axillary vein transfer, in combination with other antirefluxive procedures when indicated, is safe, effective, and durable in patients with trabeculated veins and severe forms of postthrombotic syndrome. It may be considered as an option when conservative therapy or other types of surgery fail.

Axillary Vein↗
PubMed1999

Studies in calf venous pump function utilizing a two-valve experimental model.

OBJECTIVES: to explore the hydrodynamic mechanisms involved in the regulation of ambulatory venous pressure. DESIGN: an experimental model of calf venous pump was constructed with collapsible tubes and valves. MATERIAL: the model consisted of a conduit and a pump with an intervening competent valve. Another valve that could allow reflux into the pump was mounted above the pump. METHODS: conduit pressure and recovery times were monitored under conditions of different degrees of ejection fraction and reflux into the pump. Model variables included using poorly compliant tubes for the pump, the conduit and for both the pump and conduit. RESULTS: the latex tube exhibited a non-linear volume-pressure relationship and a bi-modal regimen of compliance. This bestowed pressure-buffering properties. Ambulatory venous hypertension resulted when reflux beyond buffering capacity occurred. Substituting less compliant PTFE for latex at the pump had a relatively minor effect on post-ejection pressure and recovery times. Using PTFE at the conduit had a profound but divergent effect on both of these parameters. Conduit capacitance reduction had a similar effect. CONCLUSION: conduit elastance plays a significant role in the regulation of ambulatory venous pressure in this experimental model. The hydrodynamic principles illustrated by the model may enhance our understanding of the human calf venous pump.

Blood Pressure Determination↗
PubMed1999

Enterotoxigenicity of Klebsiella pneumoniae associated with childhood gastroenteritis in Madras, India.

Klebsiella pneumoniae was isolated as the predominant growth from 12 of 100 children under 3 years of age suffering from acute diarrhea. Of the 12 isolates, SA1, SA2, SA4, SA5, SA6 produced a secretogenic response in the ligated rabbit ileal loop, and one isolate, SA3, induced a diarrheagenic response in suckling mice. Two isolates, SA7 and SA8, were diarrheagenic in both assays. Strains SA9, SA10, SA11, and SA12 were found to be non-enterotoxigenic. These isolates belonged to serotypes K6, 16, 25, 30, 39, 46, 49, 53, 66, and 81. All eight enterotoxigenic strains were resistant to ampicillin, streptomycin, ceftazidime, cefuroxime, and cotrimoxazole. Only quinolones such as ciprofloxacin and norfloxacin appear to be effective against enterotoxigenic K. pneumoniae.

Animals↗
PubMed1998

Axial transformation of the profunda femoris vein.

PURPOSE: To highlight a special subset of cases of venous stasis in which the profunda femoris vein enlarges to a variable extent (axial transformation) to compensate for severe postthrombotic changes in the accompanying superficial femoral vein. METHODS: Among 500 consecutively treated patients with severe venous stasis, 57 patients had axial transformation of the profunda femoris vein. Venous obstruction and reflux were assessed by means of arm-foot pressure differential, ambulatory venous pressure measurement, air plethysmography, and duplex examination. Ascending and descending venograms also were obtained. A variety of valve reconstruction techniques were useful in correcting reflux in the enlarged profunda femoris vein and the companion postthrombotic superficial femoral vein. RESULTS: In 55% of patients the profunda femoris vein was larger than normal and provided partial outflow from the leg through a profunda-popliteal connection, but the superficial femoral vein was still the dominant outflow tract (grades I and II). In 36% of patients the profunda femoris was the dominant outflow tract from the leg, and in another 9% it was the sole axial outflow tract (grades III and IV). The skin changes of advanced venous stasis were present among 92% of patients and frank ulceration among 88%. Antireflux operations on the profunda femoris vein and companion superficial femoral vein, including ligation and division in some instances, were well tolerated. Despite a postthrombotic cause, obstruction did not worsen after surgical treatment, and reflux improved according to most laboratory measurements. Complete ulcer healing was obtained with the surgical techniques described. The actuarial recurrence-free survival rates were 90% 1 year and 66% 5 years after treatment. CONCLUSION: Axial transformation of the profunda femoris vein is present in a subset of instances in which severe postthrombotic changes are present in the companion superficial femoral vein. Profunda femoris reflux is invariably present in these instances because of compensatory dilatation and enlargement of this vessel. Simultaneous valve repair of the axially transformed profunda femoris vein and companion superficial femoral vein to abolish reflux yields excellent long-term results and healing of stasis ulceration.

Actuarial Analysis↗