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41.
Pai RG Jintapakorn W Tanimoto M Cao QL Pandian N Shah PM 《Echocardiography (Mount Kisco, N.Y.)》1996,13(6):613-622
Accurate determination of left ventricular (LV) volume has important therapeutic and prognostic implications in patients with cardiac disease. Volume estimations by two-dimensional techniques are not very accurate due to geometric assumptions. OBJECTIVES: To validate LV volume determinations by a new transesophageal three-dimensional echocardiographic technique. We performed three-dimensional reconstruction of the LV using an echo-computed tomographic (CT) technique based on serial pullback parallel slice imaging technique in both in vitro and in vivo settings. Fourteen latex balloons with various sizes (30-235 mL) and shapes (conical, pear shaped, round, elliptical, and aneurysms in various locations) filled with known volumes of water were imaged in a water bath. From the static three-dimensional image, the LV long axis was defined and the LV was sectioned perpendicular to this axis into 2-mm slices. The volume of each slice was calculated with the observer blinded to the actual volume as the product of the slice thickness and the manually traced perimeter of the slice and the LV volume as the sum of the volumes of the slices (Simpson's method). The calculated LV volume closely correlated with the actual volume (r = 0.99, P < 0.0001, calculated volume = 1.06x - 11.3, Deltavolume = -5.7 +/- 10.0 cc). Using the same system, transesophageal echocardiographic (TEE) images of the LV were obtained in 15 patients gated to respiration and ECG. Satisfactory dynamic three-dimensional reconstruction of the LV was possible in ten patients. The three-dimensional LV volumes (systolic and diastolic) using Simpson's method correlated well with those obtained from biplane or multiplane TEE images using the area length method (r = 0.89, p < 0.0001, y = 12.7 + 0.84x, Deltavolume = 1.3 +/- 18.1 cc). The LV major-axis diameters by the two methods showed very close correlations as well (r = 0.86, P < 0.0001, y = 19 + 0.74x, Deltadiameter = 1.0 +/- 7.2 mm). We conclude that three-dimensional LV volume calculation by the echo-CT technique is intrinsically sound, is independent of LV geometry, and with some limitations, is applicable in vivo. (ECHOCARDIOGRAPHY, Volume 13, November 1996) 相似文献
42.
Pai Sudhakar M. Fettner Scott H. Hajian Gerald Cayen Mitchell N. Batra Vijay K. 《Pharmaceutical research》1996,13(9):1283-1290
Purpose. The objective of this work was to develop and validate blood sampling schemes for accurate AUC determination from a few samples (sparse sampling). This will enable AUC determination directly in toxicology studies, without the need to utilize a large number of animals.
Methods. Sparse sampling schemes were developed using plasma concentration-time (Cp-t) data in rats from toxicokinetic (TK) studies with the antiepileptic felbamate (F) and the antihistamine loratadine (L); Cp-t data at 13–16 time-points (N = 4 or 5 rats/time-point) were available for F, L and its active circulating metabolite descarboethoxyloratadine (DCL). AUCs were determined using the full profile and from 5 investigator designated time-points termed critical time-points. Using the bootstrap (re-sampling) technique, 1000 AUCs were computed by sampling (N = 2 rats/point, with replacement) from the 4 or 5 rats at each critical point. The data were subsequently modeled using PCNONLIN, and the parameters (ka, ke, and Vd) were perturbed by different degrees to simulate pharmacokinetic (PK) changes that may occur during a toxicology study due to enzyme induction/inhibition, etc. Finally, Monte Carlo simulations were performed with random noise (10 to 40%) applied to Cp-t and/or PK parameters to examine its impact on AUCs from sparse sampling.
Results. The 5 time-points with 2 rats/point accurately and precisely estimated the AUC for F, L and DCL; the deviation from the full profile was ~10%, with a precision (%CV) of ~15%. Further, altered kinetics and random noise had minimal impact on AUCs from sparse sampling.
Conclusions. Sparse sampling can accurately estimate AUCs and can be implemented in rodent toxicology studies to significantly reduce the number of animals for TK evaluations. The same principle is applicable to sparse sampling designs in other species used in safety assessments. 相似文献
43.
Ira Pastan Lee H. Pai Ulrich Brinkmann David FitzGerald 《Breast cancer research and treatment》1996,38(1):3-9
Summary
Pseudomonas exotoxin has been genetically modified so that it targets cancer cells. This was accomplished by deleting its cell binding domain and replacing it with Fv fragments of antibodies that react with breast, colon, and other cancers. Several recombinant immunotoxins are now in clinical trials.Presented at the symposium "New Approaches in the Therapy of Breast Cancer", Georgetown University Medical Center, Washington DC, October 1994, generously supported by an education grant from Bristol-Myers Squibb. 相似文献
44.
Calhoun TR Wright RM Cimo PL Pai A Windham PA Kitten CM 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》1983,10(4):347-350
An increasing incidence of nonmalignant, indwelling catheter cases has been reported in relation to superior vena cava syndrome. Such cases may be life-threatening, with rapid development of facial and neck edema and the production of respiratory distress. This is the first reported case of atrial and superior vena caval thrombectomy requiring cardiopulmonary bypass; it is only the second case reported in which operative thrombectomy has been used. Because of the problems associated with an increase in the use of indwelling venous catheters and the satisfactory results we obtained in this case, such an aggressive form of treatment for acute, benign superior vena cava syndrome may be used more frequently in the future. 相似文献
45.
S Laskar T Gupta S Vimal M A Muckaden T K Saikia S K Pai K N Naresh K A Dinshaw 《Journal of clinical oncology》2004,22(1):62-68
PURPOSE: Combined modality treatment using multidrug chemotherapy (CTh) and radiotherapy (RT) is currently considered the standard of care in early stage Hodgkin's disease. Its role in advanced stages, however, continues to be debated. This study was aimed at evaluating the role of consolidation radiation in patients achieving a complete remission after six cycles of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) chemotherapy using event-free survival (EFS) and overall survival (OS) as primary end points. PATIENTS AND METHODS: Two hundred and fifty-one patients with Hodgkin's disease attending the lymphoma clinic at the Tata Memorial Hospital (Mumbai, India) from 1993 to 1996 received induction chemotherapy with six cycles of ABVD after initial staging evaluation. A total of 179 of 251 patients (71%) achieved a complete remission after six cycles of ABVD chemotherapy and constituted the randomized population. Patients were randomly assigned to receive either consolidation radiation or no further therapy. RESULTS: With a median follow-up of 63 months, the 8-year EFS and OS in the CTh-alone arm were 76% and 89%, respectively, as compared with 88% and 100% in the CTh+RT arm (P =.01; P =.002). Addition of RT improved EFS and OS in patients with age < 15 years (P =.02; P =.04), B symptoms (P =.03; P =.006), advanced stage (P =.03; P =.006), and bulky disease (P =.04; P =.19). CONCLUSION: Our study suggests that the addition of consolidation radiation helps improve the EFS and OS in patients achieving a complete remission after six cycles of ABVD chemotherapy, particularly in the younger age group and in patients with B symptoms and bulky and advanced disease. 相似文献
46.
Liu JM; Chen YM; Chao Y; Liu SM; Tiu CM; Wu HW; Chiou TC; Hsieh RK; Chen LT; Whang-Peng J 《Japanese journal of clinical oncology》1998,28(7):431-435
BACKGROUND: To evaluate the efficacy and toxicity of cisplatin/etoposide
continuous infusion chemotherapy for cancer of unknown primary site in
Taiwan, a region with a high prevalence of endemic viral infections.
METHOD: Between April 1994 and February 1996, 20 patients with a diagnosis
of CUPS were treated, including 15 males and five females, of average age
63.3 years (range 41-83 years). Continuous intravenous infusion of
etoposide 80 mg/m2 and cisplatin 25 mg/m2 was given for 3 days every 3
weeks. Pretreatment tumor marker and viral serology studies were performed
for baseline evaluation. Nearly two-thirds of the patients had poorly
differentiated carcinoma. The average number of metastatic sites was 2.65
(range 1-4), with liver and lymph node involvement predominating. RESULTS:
The overall response rate was 25% (95% CI 17.7-32.3%); 30.7% for poorly
differentiated cancers and 25% for well differentiated cancers. Median
survival was 4 months (range 1-12 months), 4.8 months for patients
attaining partial response. Toxicity was moderate, grade 3 and 4
neutropenia occurred in 55% and grade 3 and 4 thrombocytopenia in 40%;
other toxicities were mild. CA125 and CA199 were elevated in more than 50%
of patients. Viral serology studies were not significantly different from
those of the indigenous population. CONCLUSION: Etoposide and cisplatin
combination chemotherapy has modest activity in patients with extensive
CUPS and, at the schedule and dosage given, it is associated with moderate
toxicity.
相似文献
47.
Wang WS; Hsieh RK; Chiou TJ; Liu JH; Fan FS; Yen CC; Tung SL; Chen PM 《Japanese journal of clinical oncology》1998,28(9):551-554
A 54-year-old man was treated with weekly 24-h infusion of high-dose
5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon
cancer. At first, he tolerated the treatment well and no significant
toxicity was identified. After a total of eight courses of treatment, a
stable disease was observed, but mild shortness of breath was found on
occasion. The patient had no previous history of cardiac disease and the
heart performance assessed by left ventricular ejection fraction before
treatment was normal. Unfortunately, acute pulmonary edema with lethal
cardiogenic shock occurred during the ninth course of treatment, in spite
of intensive medical treatment. The chest X-ray showed extreme
cardiomegaly. Repeated assessment of his heart function by echocardiogram
and ventricular ejection fraction revealed a very poor cardiac performance.
Toxic cardiogenic shock during weekly 24-h infusion of high-dose
5-fluorouracil and leucovorin is extremely rare. To the best of our
knowledge, no case has been reported in the English literature. We report a
case and the relevant literature about the incidence, clinical picture and
possible pathophysiology on 5-fluorouracil-related cardioxicity is
reviewed.
相似文献
48.
49.
50.
Imaging of malignant lymphomas with F-18 FDG coincidence detection positron emission tomography 总被引:1,自引:0,他引:1
PURPOSE: The authors evaluated the utility of F-18 fluorodeoxyglucose (FDG) coincidence detection (CoDe) positron emission tomography (PET) for staging, post-treatment evaluation, and follow-up assessment of patients with malignant lymphomas. MATERIALS AND METHODS: Fifty-eight patients with histologically proved malignant lymphomas (4 Hodgkin's disease, 54 non-Hodgkin's lymphoma) underwent CoDe PET using F-18 FDG. CoDe PET was performed using a dual-head gamma camera equipped with coincidence detection circuitry. Of the 87 CoDe PET studies, 26 were performed for staging, 38 for post-treatment evaluation, and 23 for follow-up evaluation of recurrence. The entire trunk, from the cervical to the inguinal regions, or selected regions were scanned with the patient in the supine position. No attenuation correction was made and reconstruction was performed using filtered back-projection rather than iterative reconstruction. CoDe PET findings were compared with corresponding results of computed tomographic (CT) and magnetic resonance imaging (MRI), tissue biopsy, or clinical follow-up. RESULTS: For staging, 52 sites were positive on CoDe PET or CT-MRI. CoDe PET detected 49 sites (94%), and CT-MRI showed 47 sites (90%). CoDe PET detected five more lymphomatous lesions and missed three lesions. For post-treatment evaluation, CoDe PET showed a positive predictive value of 100% and a negative predictive value of 83%, but the validated cases numbered only 11. For follow-up for recurrence, CoDe PET had a negative predictive value of 90%, but frequent false-positive findings were noted in the head and neck region as a result of underlying inflammatory changes. CONCLUSIONS: For staging, FDG CoDe PET alone without attenuation correction is not sensitive enough to be used as an independent imaging method, especially for small abdominal lesions. However, it appears to be an accurate method for assessing residual disease and for patient follow-up. 相似文献