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Biomedical subjects

S Roy

Publications and source records attributed to S Roy.

At least 1,027 records · Page 57Linked to original sources
PubMedDate not supplied

Left cervical arch and associated abnormalities.

Cervical aortic arch is a rare congenital anomaly. Occasionally it is associated with other cardiac and aortic abnormalities. This paper describes the association of a left cervical aortic arch with a fusiform aneurysm of the arch in one patient and with multiple coarctations in another.

Adolescent↗
PubMedDate not supplied

Evaluation of clinico-immunological parameters in pediatric ABPA patients.

Allergic bronchopulmonary aspergillosis patients (ten in the age group 5-13) were studied with respect to clinical and immunodiagnostic tests. All the patients showed wheal and flare reaction with A. fumigatus antigens. Clinical features included bilateral infiltration and hilar lymphadenopathy. Eosinophilic count in these patients was observed to be in the range of 300-2500/mm3. Sera of six patients indicated precipitin reaction with A. fumigatus antigens. An elevated total serum IgE was noticed in all the patients. A. fumigatus specific IgG and IgE antibodies were increased in these patients. Optical density of the sera of all the patients against controls were observed to be in the range of (0.426 to 1.8 for IgG and 0.147 to 0.562 for IgE) by ELISA. Western blot analysis indicated that there may be correlation between the clinical stages of the disease and immunological reactivity of the sera with various antigenic components.

Adolescent↗
PubMedDate not supplied

Animal model of acute deep vein thrombosis.

PURPOSE: To develop an animal model of acute deep vein thrombosis (DVT). METHODS: In part I of the study nine juvenile domestic pigs were used. Each external iliac vein was transluminally occluded with a balloon catheter. Thrombin was infused through a microcatheter in one leg according to one of the following protocols: (1) intraarterial (IA): 1250 U at 25 U/min in the common femoral artery (n = 3); (2) intravenous (IV): 5000 U in the popliteal vein at 500 U/min (n = 3), or at 100 U/min (n = 3). Saline was administered in the opposite leg. After the animals were killed, the mass of thrombus in the iliofemoral veins was measured. The pudendoepiploic (PEV), profunda femoris (PF), and popliteal veins (PV) were examined. Thrombosis in the tributaries of the superficial femoral vein (SFVt) was graded according to a three-point scale (0, +, ++). In part II of the study IV administration was further investigated in nine pigs using the following three regimens with 1000 U at 25 U/min serving as the control: (1) 1000 U at 100 U/min, (2) 250 U at 25 U/min, (3) 250 U at 6.25 U/min. RESULTS: All animals survived. In part I median thrombus mass in the test limbs was 1.40 g as compared with 0.25 g in the controls (p = 0.01). PEV, PFV and PV were thrombosed in all limbs infused with thrombin. IV infusion was more effective in inducing thrombosis in both the parent veins (mass 1. 32-1.78 g) and SVFt (++ in 4 of 6 legs), as compared with IA infusion (mass 0.0-1.16 g; SFVt ++ in 1 of 3 legs). In part II thrombus mass in axial veins ranged from 1.23 to 2.86 g, and showed no relationship with the dose of thrombin or the rate of infusion. Tributary thrombosis was less extensive with 250 U at 25 U/min than with the other regimens. CONCLUSION: Slow distal intravenous thrombin infusion in the hind legs of pigs combined with proximal venous occlusion induces thrombosis in the leg veins that closely resembles clinical DVT in distribution.

Animals↗
PubMedDate not supplied

Selective thrombolysis in acute deep vein thrombosis: evaluation of adjuvant therapy in vivo.

PURPOSE: To evaluate in a porcine model of acute deep vein thrombosis (DVT) the efficacy of dalteparin and antithrombin with respect to heparin for local adjuvant therapy during selective thrombolysis, and the utility of nitroglycerin and iloprost as heparin supplements. METHODS: DVT was induced in both hind limbs using a previously described technique (n = 20). Thirty minutes later, the animal was heparinized (2500 IU IV), and bilateral sequestrated thrombolysis was performed using 8 mg alteplase: both external iliac veins were endoluminally occluded with Swan-Ganz catheters, and a multi-sideport infusion wire coaxially introduced through each catheter and advanced into the ipsilateral popliteal vein. In the control limbs, tissue plasminogen activator (tPA) 8 mg was injected as 0.8-ml boluses at 3-min intervals for 2 hr as a 0. 25-mg/ml solution containing heparin 50 IU/ml (n = 20). On the contralateral side, heparin was substituted with either dalteparin 50 IU/ml (n = 5) or antithrombin 12.5 IU/ml (n = 5), or supplemented with either nitroglycerin 0.075 mg/ml (n = 5) or iloprost (150 ng/ml) (n = 5). Blood samples were taken at predetermined intervals to measure the activated partial thromboplastin time (aPTT), prothrombin time (PT), and fibrinogen concentration. At autopsy, the thrombus mass in the iliofemoral veins was measured, and the extent of residual thrombosis in the venous tributaries graded at four sites. RESULTS: Bilateral thrombolysis was successfully completed in all animals. The median thrombus mass in the iliofemoral veins after thrombolysis was 0.48 g (range 0.06-1.58 g), 0.95 g (0.59-1.29 g), 0. 74 g (0.52-0.96 g), and 0.29 g (0.0-0.77 g) for dalteparin, antithrombin, iloprost, and nitroglycerin respectively, as compared with 0.53 g (0.18-0.88 g) (p = 0.69), 0.97 g (0.46-1.15 g) (p = 0. 69), 0.53 g (0.48-1.10 g) (p = 0.69), and 0.18 g (0.13-1.04 g) (p = 0.5) for the respective controls. Likewise, the severity of residual thrombosis in the venous tributaries was not affected by the constituents of adjuvant therapy. Nitroglycerin induced a small drop in blood pressure, which was transient. The temporal change in aPTT was similar in all four groups. Invariably PT progressively shortened during thrombolysis (p = 0.0001); this effect was somewhat blunted with antithrombin. Fibrinogen levels demonstrated a time-dependent increase (p = 0.004) that was not influenced by the adjuvant therapy used. CONCLUSIONS: Dalteparin or antithrombin demonstrated no appreciable advantage over heparin as local adjuvant therapy for selective venous thrombolysis. Supplementation of heparin with iloprost or nitroglycerin also had virtually no effect on thrombolytic efficacy.

Animals↗
PubMedDate not supplied

Sequestrated thrombolysis: comparative evaluation in vivo.

PURPOSE: Lysis of a thrombus is a function of the local concentration of thrombolytic enzymes. This study was designed to determine in a porcine model of acute deep vein thrombosis (DVT) whether perithrombic sequestration of small volumes of a concentrated enzyme solution can accelerate the process of thrombolysis. METHODS: DVT was induced in both hind limbs using a previously described technique (n = 32). Thirty minutes later the animal was heparinized and unilateral thrombolysis was attempted using 8 mg recombinant tissue plasminogen activator (rt-PA); saline was administered in the opposite leg. For conventional high-volume infusion (CI) (n = 5) rt-PA (0.067 mg/ml) was infused at 1 ml/min. For sequestrated thrombolysis the external iliac vein was endoluminally occluded, and rt-PA (0.25 mg/ml) administered either for proximal injection (ST-P) (n = 5), as a bolus every 3 min through a microcatheter placed via the balloon catheter, or for transthrombic injection (ST-T) (n = 5), as a bolus every 3 min through a Katzen wire in the balloon catheter. At autopsy, the thrombus mass in the iliofemoral veins was measured, and the extent of residual thrombosis in the venous tributaries graded at four sites. From these data a thrombolysis score was calculated. RESULTS: One pig died before thrombolysis could be performed. Only with ST-T was residual thrombus mass in the test limb normalized to control, residual thrombus index (RTI), consistently less than unity. The median RTI of this group was 0.50 (range 0.39-0.97) compared with 1.22 (0.64-1.38) for ST-P and 0.88 (0.37-1.13) for CI. Compared with contralateral controls, a lower grade of residual thrombosis in tributaries was observed in test limbs at more venous sites with ST-T (8/20; 95% confidence interval 5-13) and ST-P (9/20; confidence interval 5-13) than with CI (2/20; confidence interval 0-5) (p = 0.04). A trend toward lower thrombolysis scores was observed with ST-T (p = 0.08). Systemic fibrinogenolysis was not observed in any of the groups. Changes in coagulation parameters during thrombolysis were similar irrespective of treatment protocol. CONCLUSIONS: "Transthrombic" sequestrated thrombolysis may offer some advantages over conventional selective infusion for the treatment of acute DVT. However further refinements will be necessary before it can be considered an alternative to the latter.

Acute Disease↗
PubMedDate not supplied

Immunosuppression in broilers under experimental aflatoxicosis.

The effects of purified aflatoxin B1 on cell mediated immunity in broilers were carried out using 0.3 p.p.m. and 1 p.p.m. dose level. The percentage of acid alpha-naphthyl acetate esterase reacting lymphocytes was significantly (P less than 0.05) decreased in chicks fed 0.3 p.p.m. and 1 p.p.m. level of aflatoxin B1. The albumin and globulin values were also significantly decreased (P less than 0.05) at both dose levels.

Aflatoxin B1↗
PubMedDate not supplied

Use of tetracycline sorbate for the treatment of Aspergillus fumigatus infection in broiler chicks.

The efficacy of tetracycline sorbate (Pimafungil; contains 20% tetracycline sorbate w/v) was evaluated for treatment of Aspergillus fumigatus in naturally infected broiler chicks. The drug was administered to a group of 160 infected broiler chicks at 200 mg/l of drinking water, daily and consecutively for 5 days. Another group of 100 infected broiler chicks was kept as untreated controls. The chicks of the treated group showed appreciable improvement in clinical symptoms, mortality, body weight and recovery as shown by absence of gross and histopathological lesions and of the fungus.

Animals↗
PubMedDate not supplied

Cerebrovascular complications in children with nephrotic syndrome.

Although the nephrotic syndrome is known to be a hypercoagulable state, cerebral arterial thrombosis associated with the nephrotic syndrome is an uncommon yet treatable cause of stroke syndrome in children. We report 2 children, 1 with congenital nephrotic syndrome and the other with minimal change nephrotic syndrome, who developed cerebral arterial thrombosis. The complication was fatal in 1 patient.

Child↗
PubMedDate not supplied

Pancreatic adenocarcinoma presenting with ureteric metastases. Case report and review of literature.

We report a patient with pancreatic adenocarcinoma presenting with ureteric metastases. A low index of suspicion led to incomplete radiographic evaluation, and the etiology could not be established prior to laparotomy. The differential diagnosis of ureteric strictures is reviewed, with a view to providing a simple diagnostic flow chart that should prove satisfactory in all but the most exceptional cases.

Adenocarcinoma↗
PubMedDate not supplied

Comparison of three treatment regimens with liposomal amphotericin B (AmBisome) for visceral leishmaniasis in India: a randomized dose-finding study.

The efficacy and safety of 3 regimens of liposomal amphotericin B (AmBisome) in the treatment of Indian visceral leishmaniasis were compared in a prospective open randomized trial. Thirty parasitologically confirmed patients were randomly divided into 3 equal treatment groups; group 1 received AmBisome 2mg/kg on days 1, 2, 3, 4, 5, 6, and 10 (total dose 14 mg/kg); group 2 received AmBisome 2 mg/kg on days 1, 2, 3, 4, and 10 (total dose 10 mg/kg); group 3 received the same dosage on 1, 5 and 10 (total dose 6 mg/kg). Clinical cure resulted in all patients by day 24. Haemoglobin, white blood cell count, body weight and serum albumin level improved on day 24 and became normal by day 180. No patient relapsed within 12 months of follow-up. Side effects were minimal. One patient in group 2 died after 2 months from an unrelated disease. Liposomal amphotericin B is a promising new drug which is highly efficacious in the treatment of Indian kala-azar and produces minimal toxicity.

Adult↗
PubMedDate not supplied

Corn husk oil lowers plasma LDL cholesterol concentrations by decreasing cholesterol absorption and altering hepatic cholesterol metabolism in guinea pigs.

To test the hypocholesterolemic mechanisms of corn husk oil (CoHO), male Hartley guinea pigs were fed diets containing increasing doses of CoHO, either 0 (control), 5, 10, or 15 g/100 g, and 0.25 g/100 g cholesterol. A positive control group (LC) with low dietary cholesterol (0.04 g/100 g) was also included. Fat was adjusted to 15 g/100 g in all diets by the addition of regular corn oil. Plasma low density lipoprotein (LDL) cholesterol concentrations were 32, 55, and 57% (P < 0.0005) lower with increasing doses of CoHO. In addition, intake of CoHO resulted in 32 to 43% lower hepatic total and esterified cholesterol and 55 to 60% lower triacylglycerol concentrations compared with the control group (P < 0.01). CoHO intake resulted in plasma and hepatic cholesterol concentrations similar to those in guinea pigs from the LC group. The number of cholesteryl ester and free cholesterol molecules was higher in LDL from the control group than in LDL from the CoHO or the LC groups. Hepatic beta-hydroxy-beta-methylglutaryl-coenzyme A reductase activity was not modified by CoHO intake whereas cholesterol 7alpha-hydroxylase was up-regulated by 45 to 49% (P < 0.01) in the 10 and 15 g/100 g CoHO groups. Hepatic acyl coenzyme A cholesterol acyltransferase activity was down-regulated in a dose-dependent manner by 54, 58, and 63% with increasing doses of CoHO. CoHO intake resulted in increased fecal cholesterol excretion by 40 to 55% compared with the control and LC groups. Total fecal neutral sterol excretion was enhanced 42 to 55% by CoHO compared with the control group and by 59 to 68% compared with the LC group. The data from these studies suggest that CoHO has its hypocholesterolemic effect by decreasing cholesterol absorption and increasing bile acid output. These alterations in the intestinal lumen alter hepatic cholesterol metabolism and may affect the synthesis and catabolism of lipoproteins.

Journal Article↗
PubMedDate not supplied

Complement activation by angiographic catheters in vitro.

PURPOSE: Four different polymers used in commercial angiographic catheters were compared in vitro with respect to their ability to activate the complement system. MATERIALS AND METHODS: Commercially available angiographic catheters made from one of the following plastics were used: polyamide, polyethylene, polyurethane, and polytetrafluoroethylene. Silicone-coated latex urinary catheters served as the reference standard. Each catheter was cut into 20-mm segments, immersed in a polypropylene tube containing fresh serum from a volunteer donor, and incubated at 37 degrees C. Samples were drawn at 15 minutes, 1 hour, and 6 hours; C3 activation products (C3AP) and the terminal complement complex (TCC) content were estimated with enzyme immunoassays. RESULTS: By 1 hour, a significant increase in C3AP and TCC concentrations was observed with all angiographic catheters relative to controls (P < .01-.001). The time-concentration plots for both C3AP and TCC were steepest for polyamide. C3AP concentrations relative to controls were significantly higher with exposure to polyamide compared with polyurethane at 1 hour (P < .01), and with both polyethylene and polyurethane at 6 hours (P < .01). Polytetrafluoroethylene induced larger amounts of C3AP formation by 6 hours than polyethylene and polyurethane (P < .05). However, polytetrafluoroethylene was associated with the lowest relative median concentrations of TCC; the difference with polyamide was significant at 6 hours (P < .001). As with C3AP, differences in TCC generation between polyethylene and polyurethane were marginal at all observation points (P > .05). CONCLUSIONS: All the polymers tested activated the complement system. Activation was most prominent with exposure to polyamide and least marked with polyurethane.

Angiography↗