Mesolimbic dopaminergic dysfunction in Parkinson's disease depression: evidence from a 123I-FP-CIT SPECT investigation.

We investigated the striatal and extrastriatal DAT availability (SPM8) by [(123)I]FP-CIT-SPECT in 15 PD patients with depression and 35 PD patients without depression. A cluster with significant (p < 0.05) lower tracer binding in PD with depression was found in left cingulate cortex, persistent after correction for age, disease severity and duration, and inversely correlated with depression scores (r -0.336, p < 0.05). Our data indicate a significant association between PD depression and cingulate dopaminergic denervation supporting the dopaminergic hypothesis of PD depression.

Effects of long-term treatment with verapamil on left ventricular function and myocardial blood flow in patients with dilated cardiomyopathy without overt heart failure.

Myocardial blood flow (MBF) abnormalities are present in early stage dilated cardiomyopathy (DCM) and have been attributed to coronary microvascular abnormalities. The favorable effects of verapamil on coronary microcirculation might indicate its use in early stage DCM. We assessed the safety of long-term combination therapy of verapamil and enalapril and its effects on both left ventricular function and myocardial perfusion compared with enalapril alone in 18 patients with DCM (15 men, 3 women; mean age, 50+/-9 years) without overt heart failure (NYHA class I-II). At baseline and after 6 months of randomized treatment with either enalapril (10-20 mg) (nine patients, group 1) or enalapril (10-20 mg) and verapamil (120-240 mg) (nine patients, group 2), left ventricular function was assessed at rest, during handgrip, and during bicycle exercise by equilibrium radionuclide angiography. Mean MBF was measured at rest and after dipyridamole by positron emission tomography (PET) and 13N-ammonia as a flow tracer. At baseline, the two groups had reduced left ventricular ejection fraction at rest, which was further impaired during isometric exercise, but increased at peak bicycle exercise. MBF was similarly reduced in the two groups at rest and during dipyridamole. During treatment, no adverse events occurred in either group. After 6 months there was no significant difference in the main study variables either between the two groups or within each group before and after treatment. Long-term combination therapy with verapamil and enalapril is safe in patients with DCM without overt heart failure. Despite no favorable effect on myocardial perfusion, combined treatment prevented deterioration of left ventricular function, similarly to enalapril alone.

Role of 2-[18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET) in the early assessment of response to chemotherapy in metastatic breast cancer patients.

We investigated the role of 2-[18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET) in the early evaluation of response to chemotherapy in metastatic breast cancer patients. Breast cancer patients who received an epirubicin/paclitaxel--containing regimen as first-line treatment for metastatic disease were included in this study. A PET study was performed within 1 week before the start of treatment, at day 8 after the first course, and at the end of the planned program of chemotherapy. Tumor response was determined clinically and radiographically every 2 courses of treatment. Thirteen patients with metastatic breast cancer who were referred for treatment protocols with gemcitabine/epirubicin/paclitaxel or epirubicin/paclitaxel chemotherapy regimens were included in this study. All metastatic sites were easily visualized on the baseline FDG-PET images, obtained 50 to 60 minutes after tracer injection. Nine patients who completed the planned courses of chemotherapy and the FDG-PET studies were available for analysis. In the six patients who achieved a response to treatment, median glucose standard uptake value (SUV) (semiquantitative analysis) was 7.65 (range, 3.4-12.3) at baseline, 5.7 (range, 2.8-7.6) at day 8 after the first course, and 1.2 (range, 0.99-1.3) at the end of the 6 planned courses of chemotherapy. Three patients who obtained a stable disease as best response had no significant decrease in tumor glucose SUV compared to baseline levels. Qualitative visual analysis in the six responding patients showed a decrease in delineation of tumor mass from background activity soon after the first course, while the nonresponding patients had no significant modification from basal levels. Semiquantitative FDG-PET scanning of metastatic breast cancer sites showed a rapid and significant decrease in tumor glucose metabolism soon after the first course of treatment in patients who achieved a response to first-line chemotherapy. On the contrary, no significant decrease was observed in nonresponding patients.

Regional myocardial blood flow in stable angina pectoris associated with isolated significant narrowing of either the left anterior descending or left circumflex coronary artery.

Myocardial perfusion measurements were obtained with positron emission tomography under basal conditions and after intravenous dipyridamole infusion (0.56 mg/kg over 4 minutes) to determine if myocardial perfusion is maximized in areas of resting wall motion abnormalities in patients with stable angina. Thirty-three patients with no history of myocardial infarction, and with coronary stenosis > 50% involving the left anterior descending (n = 24) and left circumflex (n = 9) coronary arteries were evaluated. Quantitative perfusion images were recorded twice in each subject using nitrogen-13 ammonia at baseline and after intravenous administration of dipyridamole. Computer-assisted analysis of left ventriculograms showed abnormal wall motion in the stenosis-related regions in 16 patients (group 1), and normal regional function in 17 (group 2). The flow values in the anterior and posterolateral wall were considered to reflect left anterior and left circumflex coronary artery flow, respectively. Quantitative angiography showed that coronary stenosis severity was higher in group 1 than in group 2 (cross-sectional area reduction 94 +/- 7% vs 87 +/- 11%; p < 0.05). Resting blood flow in the stenosis-related areas was significantly lower than in contralateral regions in group 1 (0.66 +/- 0.19 vs 0.77 +/- 0.26 ml/min/g; p < 0.05), but not in group 2 (0.73 +/- 0.18 vs 0.78 +/- 0.21 ml/min/g; p = NS). Dipyridamole significantly (p < 0.01) increased myocardial blood flow in both stenotic and remote regions in both groups 1 (0.95 +/- 0.41 vs 1.57 +/- 0.70 ml/min/g) and 2 (1.54 +/- 0.53 vs 2.01 +/- 0.84 ml/min/g).(ABSTRACT TRUNCATED AT 250 WORDS)