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R Parameswaran

Publications and source records attributed to R Parameswaran.

At least 19 recordsLinked to original sources
PubMed2005

Dose effect and efficacy of rFVIIa in the treatment of haemophilia patients with inhibitors: analysis from the Hemophilia and Thrombosis Research Society Registry.

Recombinant activated factor VII (rFVIIa), licensed in 1999 for treatment of haemophilia patients with inhibitors (HI), represents an important advance in the therapeutic armamentarium. Standard bolus dosing ranges from 90 to 120 mcg kg(-1) every 2-3 h until arrest of bleeding. As licensure, clinical use of rFVIIa has increased and broadened. Clinicians now use a wide dose range, 90-300 mcg kg(-1). High-dose regimens may optimize thrombin generation or burst, and may allow for prolonged dose interval. The Hemophilia and Thrombosis Research Society (HTRS) maintains a registry database to study haemophilia treatment and related disorders, particularly treatment of acute bleeding in HI, acquired haemophilia, FVII deficiency and von Willebrand's disease (VWD). To assess the effect of rFVIIa dose on efficacy and safety in the treatment of acute bleeding in HI, data from the HTRS database from January 2000 through June 2002 were analysed. Bleeding episodes were grouped by bolus rFVIIa dose range: <100, 100-150, 150-200 and >200 mcg kg(-1). Investigator-reported efficacy for the first 72 h of treatment was evaluated. Thirty-eight congenital HI patients were treated for 555 bleeding episodes. Patient age range was 1-55 years (median: 14). Bleeding episodes were spontaneous (45%), caused by trauma (38%), or because of surgery, dental, diagnostic, or medical procedures (17%); bleeding occurred in joint, muscle, and intra/extracranial sites. Treatment location included: 80% at home, 12% at other facilities (treatment centres, ER, inpatient and OR), and 8% at both home/other facilities. Median total dose given over 72 h was 360 mcg kg(-1) (range: 40-4281, mean: 537). Bleeding stopped in 87% of the episodes. Bleeding cessation rate was 84% for the three lower dose groups, and 97% for the highest dose group (P < 0.001). Five patients experienced nine adverse events (AEs). AE rates were <1% for <100, 5% for 100-150, 0% for 150-200, <1% for >200 mcg kg(-1) dose group. Decreased therapeutic response accounted for eight of the nine AEs. These data, which represent the most comprehensive report of rFVIIa use since the USA licensure, demonstrate that bleeding episodes in HI patients can be treated safely and effectively at home and that doses up to 346 mcg kg(-1) appear to be well-tolerated. Additionally, rFVIIa doses >200 mcg kg(-1) appear to significantly increase efficacy (97% in the high-dose group, compared with 84% in the lower dose groups). Optimal dosing remains to be determined; specifically, what the lowest effective dose is and whether a single high-dose bolus eliminates the need for repeated dosing. Recombinant FVIIa appears to have a wide safety margin that may allow dose escalation to address these questions.

Adolescent↗
PubMed2004

Isolated intracranial Rosai-Dorfman disease mimicking meningioma in a child.

A 9-year-old boy presented with a 12-month history of headaches and recent grand mal seizures. Computed tomography and magnetic resonance imaging of the brain revealed an enhancing right frontal convexity lesion. The preoperative diagnosis was meningioma. However, histological examination was diagnostic of Rosai-Dorfman disease. Rosai-Dorfman disease confined to the intracranial compartment is very rare, of 34 reported cases only one presented in the first decade. Optimal treatment has not been established, but complete surgical resection alone seems effective and allows histological distinction from meningioma.

Brain↗
PubMed2001

Reduced expression of activin A in focal lymphoid agglomerates within nasal polyps.

It has been previously reported that activin A, a homodimer of the betaA inhibin subunit, is secreted by stromal cells from mouse bone marrow and causes apoptotic death of mouse plasmacytoma tumor cells. Recent in vitro studies have also implicated this cytokine in the suppression of normal B-cell lymphopoiesis. In this study we examined the occurrence of activin A in nasal polyp tissues that present a combination of epithelium, mesenchyme, and vascular endothelium, with frequent massive hemopoietic infiltration. Anti-betaA-chain antibodies strongly stained epithelial mucous glands and some endothelial cells, and diffusely stained the polyp stroma. Normal adult conchae were similarly stained, whereas activin A was not detected prenatally by immunostaining of nasal tissues. Staining specificity was substantiated by ligand competition assays. Detailed examination of the inflammatory polyp infiltrate showed that activin A staining was reduced in sites of focal infiltration of B-lymphoid cells. It is therefore implied that local accumulation of a large number of B-cells is associated with relatively low activin A expression.

Activins↗
PubMed2000

CCNU (lomustine), idarubicin and dexamethasone (CIDEX): an effective oral regimen for the treatment of refractory or relapsed myeloma.

We report the results of a non-randomized pilot study of an oral regimen comprising CCNU (lomustine; 25 or 50 mg/m2 on day 1), idarubicin (4-demethoxydaunorubicin) (10 mg/m2 on days 1-3) and dexamethasone (10 mg b.d. on days 1-4) in patients with relapsed or refractory myeloma. Treatment was given every 28 d for a maximum of six courses. Sixty patients were entered of whom 57 were evaluable. Overall response rate (partial or minor response) was 49% with 30% of patients achieving a partial response (50% tumour reduction). Response rates were higher in patients with untested relapse than in those with refractory disease (overall response rates 56% vs. 31%). The major toxicity was neutropenia and the regimen was otherwise well tolerated. The median survival from entry of all patients was 15 months, with 30% of patients alive at 2 years. This regimen represents a useful addition to available treatment options.

Adult↗
PubMed2000

Multiple myeloma and immune thrombocytopenia.

Immune thrombocytopenia (ITP) is frequently encountered in patients with lymphoproliferative disorders. However this is only rarely reported in patients with multiple myeloma. We describe three cases who presented initially with the clinical manifestations of ITP but were subsequently found to have multiple myeloma. Platelet count increments to standard treatment modalities for ITP were observed in all three patients with transient or partial response. The importance of recognizing the immune mediated thrombocytopenia in patients with myeloma and the implications of this combination are discussed.

Adult↗
PubMed1997

Haematological validation of a computer-based bone marrow reporting system.

AIMS: To prove the safety and effectiveness of "Professor Belmonte", a knowledge-based system for bone marrow reporting, a formal evaluation of the reports generated by the system was performed. METHODS: Three haematologists (a consultant, a senior registrar, and a junior registrar), none of whom were involved in the development of the software, compared the unedited reports generated by Professor Belmonte with the original bone marrow reports in 785 unselected cases. Each haematologist independently graded the quality of Belmonte's reports using one of four categories: (a) better than the original report (more informative, containing useful information missing in the original report); (b) equivalent to the original report; (c) satisfactory, but missing information that should have been included; and (d) unsatisfactory. RESULTS: The consultant graded 64 reports as more informative than the original, 687 as equivalent to the original, 32 as satisfactory, and two as unsatisfactory. The senior registrar considered 29 reports to be better than the original, 739 to be equivalent to the original, 15 to be satisfactory, and two to be unsatisfactory. The junior registrar found that 88 reports were better than the original, 681 were equivalent to the original, 14 were satisfactory, and two were unsatisfactory. Each judge found two different reports to be unsatisfactory according to their criteria. All 785 reports generated by the computer system received at least two scores of satisfactory or better. CONCLUSIONS: In this representative study, Professor Belmonte generated bone marrow reports that proved to be as accurate as the original reports in a large university hospital. The haematology knowledge contained within the system, the reasoning process, and the function of the software are safe and effective for assisting haematologists in generating high quality bone marrow reports.

Bone Marrow↗
PubMed1986

Echocardiographic analysis of left ventricular filling in isolated pure chronic aortic regurgitation.

Left ventricular (LV) diastolic filling was assessed using digitized M-mode echocardiography in 12 patients with aortic regurgitation (AR) and in 12 normal subjects. Ten patients with AR were asymptomatic and 2 patients had congestive heart failure. LV chamber dimensions, fractional shortening and the rate of change of LV dimensions during systole and diastole were determined. In addition, the timing of the rate of change of LV dimensions in diastole (peak dD/dt, 50% peak dD/dt and 20% peak dD/dt) was also measured. Patients with AR had a significant reduction in dD/dt (12.2 +/- 3.5 cm/s in patients with AR vs 15.9 +/- 1.9 cm/s in normal subjects, p less than 0.01) and a delay in the timing of peak dD/dt (160 +/- 35.2 ms in patients with AR vs 86 +/- 17.6 ms in normal subjects, p less than 0.01) from the minimum LV dimension. These diastolic abnormalities were present in patients with symptomatic as well as those with asymptomatic AR, occurred even when the fractional shortening and peak systolic emptying rate (peak -dD/dt) were normal, and showed no correlation with the calculated LV mass (r = 0.14). The delay in the diastolic filling velocities (peak dD/dt, 50% and 20% peak dD/dt) was associated with a decreased rate of change of LV dimension in diastole, suggesting delayed early LV filling. These findings indicate an abnormality of LV diastolic filling in patients with symptomatic as well as asymptomatic AR and suggest that diastolic abnormalities may precede echocardiographic indexes of systolic LV dysfunction.

Adolescent↗
PubMed1986

The complementary role of magnetic resonance imaging, Doppler echocardiography, and computed tomography in the diagnosis of dissecting thoracic aneurysms.

Non-ECG gated MRI was compared with 2DE and/or CT scans in 10 patients with dissecting aneurysms proven by angiography and/or surgery. Patient ages ranged from 48 to 85 years (mean 69.6). Six had DeBakey type I dissections and four had DeBakey type III dissections. MRI was diagnostic for aortic dissection in nine cases and suggestive in the tenth. 2DE was diagnostic in six out of nine patients, suggestive in two patients, and nondiagnostic in one patient. CT was diagnostic in the three cases in which it was employed. MRI demonstrated a dilated ascending aorta with thickened walls in all type I dissections as well as an intimal flap and slow flow in the false channel in four patients. In the other two patients with type I dissection, MRI detected the intimal flap in the descending aorta but not in the ascending aorta, whereas 2DE revealed the ascending aortic intimal flap in both of these patients and CT showed it in one of them. In the type III dissections, MRI demonstrated a thickened wall and thrombus in the lumen in all four cases, and the intimal flap in three out of the four. 2DE excluded ascending aortic involvement in all three type III dissections. Six other patients with fusiform dilated ascending aortas had no evidence of dissection by MRI, 2DE, and aortography. Thus, non-ECG gated MRI alone or in combination with 2DE and/or CT is useful in the diagnosis of dissecting thoracic aneurysm and in assessing the extent of the dissection. In addition, the differentiation of dissecting aneurysms of the aorta from fusiform dilatation of the aorta is made possible by these noninvasive techniques.

Aged↗
PubMed1986

Magnetic resonance imaging and two-dimensional echocardiography. Alternative approach to aortography in diagnosis of aortic dissecting aneurysm.

Unrecognized acute dissection of the aorta requires rapid and accurate diagnosis for appropriate management. The "gold standard" for diagnosis has been invasive angiography, but this diagnosis can be achieved noninvasively via two-dimensional echocardiography, computed tomographic scanning, and magnetic resonance imaging. Two patients are described in whom echocardiography and magnetic resonance imaging were complementary diagnostic aids. The advantages and disadvantages of echocardiography, computed tomographic scanning, magnetic resonance imaging, and aortography in aortic dissection are discussed. It is anticipated that a combination of noninvasive diagnostic aids will eliminate the need for invasive angiography in many instances in the future.

Aged↗