Radionuclide evaluation of liver transplants

Orthotopic liver transplantation is now an established technique for treating patients with various forms of end stage liver disease. The number of centers performing the procedure is increasing and, as the number of transplant recipients in the population increases, many institutions performing nuclear medicine studies will be confronted with requests to evaluate these patients. While a variety of radionuclides are proving useful in this evaluation, the 99mTc iminodiacetic acid (IDA) compounds, particularly 99mTc diisopropyl IDA (DISIDA), will probably account for the majority of radionuclide evaluations of these patients because they are well suited to monitor both structural and functional changes of the graft. The primary application of radionuclide studies is focused in the postoperative period, when problems with the vascular and biliary anastomoses, rejection, infections, and bile leaks all produce alterations in radionuclide hepatobiliary studies. Abnormalities such as rejection and infection produce primarily functional, rather than structural changes and are not easily differentiated based upon the kinetics of 99mTc-DISIDA extraction and excretion by the liver, serial imaging and correlation with clinical data is necessary in such situations. Quantitative analyses of kinetic 99mTc IDA (DISIDA) studies and quantitative approaches with other compounds such as 99mTc galactosyl-neoglycoalbumin (NGA) may permit better assessments of relatively subtle changes in liver function in the posttransplant period.     

Unmarried status is a barrier for access to treatment in patients with metastatic renal cell carcinoma

International Urology and Nephrology - We tested the effect of marital status on cytoreductive nephrectomy, metastasectomy, and systemic therapy rates, as well as on cancer-specific mortality (CSM)...     

Use of thallium-201 SPECT to quantitate malignancy grade of gliomas

A quantitative preoperative technique using thallium-201 single-photon emission computerized tomography is described which predicts whether specific gliomas are of high- or low-grade malignancy. An index, based on the ratio of thallium uptake in the tumor versus the homologous contralateral brain, was calculated and compared with tumor histology. The index in 14 patients with low-grade malignant gliomas was 1.27 +/- 0.40 in contrast to an index of 2.40 +/- 0.61 in 11 patients with high-grade malignant gliomas (p less than 0.0005). Whether gliomas were of low- or high-grade malignancy could be predicted with 89% accuracy using a threshold of 1.5. Low-grade gliomas with an index higher than 1.5 acted biologically more like high-grade tumors, and no tumor histologically classified as being of high-grade malignancy had an index lower than 1.7. This technique could help to reduce unrecognized sampling errors during needle biopsies of brain tumors, particularly of high-grade lesions classified in error as low-grade tumors due to inadequate biopsy material.     

Regulation of Bone Mineral Density in Morbidly Obese Women: A Cross-sectional Study in Two Cohorts Before and After Bypass Surgery

Background  The mechanisms by which increased body weight influence bone mass density (BMD) are still unknown. The aim of our study was to analyze the relationship between anthropometric and body composition variables, insulin growth factor-I (IGF-I), adiponectin and soluble tumor necrosis factor-α receptors (sTNFR) 1 and 2 with BMD in two cohorts of morbid obese patients, before and after bypass surgery. Methods  The first cohort included 25 women aged 48 ± 7.6 years studied before bypass surgery. The second included 41 women aged 46 ± 9.2 years, 12 months after surgery. We studied anthropometric variables obtained from whole body DEXA composition analysis. Serum IGF-I, intact serum parathyroid hormone, 25-hydroxivitamin D₃, plasma adiponectin concentrations, sTNFR1, sTNFR2 concentrations were measured. Results  In the first cohort, the BMI was 44.5 ± 3.6 kg/m², parathyroid hormone, IGF-I, and adiponectin concentrations were lower, and sTNFR1 concentrations were higher than in the second cohort. In the multiple regression analysis, BMD remained significantly associated with body fat percentage (β −0.154, p = 0.01), lean mass (β 0.057, p = 0.016) and phosphate concentration (β 0.225, p = 0.05). In the second cohort, BMI was 31 ± 5.1 kg/m². In the multiple regression analysis, BMD remained significantly associated with lean mass (β 0.006, p = 0.03). Conclusion  The inverse correlation found between body fat and BMD in the first cohort indicates morbid obesity increases the risk of osteoporosis and we found a positive correlation with lean and fat mass before bariatric surgery and with lean mass after bypass surgery.     

Association of Retinol-Binding Protein-4 (RBP4) with Lipid Parameters in Obese Women

Background  

Although the adipokine retinol-binding protein-4 (RBP4) has been implicated in the development of obesity-related insulin resistance, its role in human obesity is still unclear. Our objectives were to find out the effect on RBP4 systemic levels of a weight loss induced by gastric bypass surgery and to analyze RBP4 relationships with insulin resistance, parameters of body composition, lipid metabolism, and inflammation.