Interventricular septal motion in acute myocardial infarction with proximal and distal left anterior descending coronary lesions

To evaluate the ability of echocardiography to detect and localize lesions of the proximal and distal left anterior descending (LAD) coronary arteries, the systolic excursion of the left side of the septum and the ratio of septal to posterior wall excursion (IVS/PW) were measured in 26 patients with acute myocardial infarction (AMI) and nine normal control subjects. The patients with proximal LAD lesions had septal wall excursions of less than 3 mm, whereas in those with distal LAD lesions septal wall excursions were more than 3 mm. All patients with proximal LAD lesions showed an IVS/PW ratio of less than 0.4, but in those with distal LAD lesions the ratio was 0.4 or greater. We conclude that reduced or absent interventricular septal motion in anterior AMI suggests an LAD lesion, and a septal excursion of less than 3 mm suggests involvement of the proximal LAD artery, whereas septal excursion of 3 mm or more indicates involvement of the distal LAD artery.     

A sensitive and practical assay for thyroid-stimulating antibodies using FRTL-5 thyroid cells

A sensitive, precise and practical assay for thyroid stimulating antibodies was developed in which poorly differentiated rat thyroid cells (FRTL-5) were exposed to crude immunoglobulin fractions precipitated from serum with 15% polyethylene glycol under hypotonic conditions. After the incubation at 37 degrees C for 2 h, cAMP released into Hank's medium without NaCl was determined by radioimmunoassay. The removal of NaCl from the isotonic Hank's medium greatly enhanced cAMP production in response to both TSH and thyroid stimulating antibodies. The assay was sensitive enough to elicit an approximately 30-fold increase in cAMP at 10 mU/l bovine TSH. Thyroid stimulating activities measured using FRTL-5 cells significantly correlated with those measured using cultured porcine (r = 0.918, N = 72) or human (r = 0.830, N = 23) thyroid cells. Thyroid stimulating activities were detected in all of the 50 patients with hyperthyroid Graves' disease, the 14 patients with recurrent hyperthyroid Graves' disease, and the 25 patients with ophthalmic Graves' disease. Thyroid stimulating activity was also detected in some patients (9/24, 37.5%) with Hashimoto's thyroiditis whose serum TSH concentrations were higher than 30 mU/l. However, it was completely abolished by pre-treatment of the sera with anti-TSH antibodies. Although thyroid stimulating activities were detected in one of the patients with simple goitre (N = 10) and in one with thyroid cancer (N = 10), none of the patients with silent thyroiditis (N = 7), adenomatous goitre (N = 11), and thyroid adenoma (N = 9) were positive for thyroid stimulating antibodies.     

Perioperative changes in hepatic function as assessed by asialoglycoprotein receptor indices by technetium 99m galactosyl human serum albumin

BACKGROUND/AIMS: Perioperative changes in intrinsic hepatocyte function and functional volume were investigated. METHODOLOGY: 52 cases of liver cancer, including hepatocellular carcinoma, cholangiocellular carcinoma and metastatic carcinoma were studied. There were diagnoses of liver cirrhosis, liver fibrosis and normal liver in 20, 23 and 9 cases, respectively. Hepatic resection of subsegment, one segment, two segments and three segments were performed in 11, 6, 23 and 4 cases, respectively, while 8 cases were diagnosed as inoperable. Assessments were performed before and 4 weeks after hepatectomy with asialoglycoprotein (ASGP) receptor indices, i.e., technetium-99m-galactosyl human serum albumin (TcGSA) uptake by the liver, TcGSA retention in the blood and functional volume as measured by single emission computed tomography (SPECT) with TcGSA as a probe. RESULTS: The hyperbolic relationship between galactosyl human serum albumin (GSA) uptake by the liver and GSA retention in the blood, both of which were independent of functional volume, shifted to the right after hepatectomy. The number of conventional liver function tests correlating to the GSA uptake increased after hepatectomy. By contrast, none of the pre-operative and post-operative tests were correlated with functional volume. Post-operative decrease in intrinsic hepatocyte function can be minimized by selection of mode of hepatic resection. CONCLUSIONS: These results indicate that GSA uptake by the liver can reveal information regarding intrinsic liver function which deteriorates and becomes a decisive factor after hepatectomy.     

A sensitive and practical assay for thyroid-stimulating antibodies using crude immunoglobulin fractions precipitated with polyethylene glycol

A simple, sensitive, and practical assay for thyroid-stimulating autoantibodies (TSAb) was developed in which cryopreserved porcine thyroid cells were incubated with crude immunoglobulin fractions sedimented from serum with polyethylene glycol. In the assay, 1.4- to 2.0-fold and 6- to 12-fold increases in cAMP released into Hank's medium without NaCl were found at 1 and 10 microU/ml bovine TSH, respectively. TSAb were detected in 41 (97.6%) of 42 patients with untreated hyperthyroid Graves' disease, 29 (55.8%) of 52 patients with hyperthyroid Graves' disease who were euthyroid while taking antithyroid drugs, 22 (78.6%) of 28 patients with euthyroid Graves' disease, and none of the patients with simple goiter, adenomatous goiter, thyroid adenoma, or thyroid cancer tested. TSAb activities measured using porcine thyroid cells significantly correlated with those measured using human thyroid adenoma cells (r = 0.908; n = 46; P less than 0.001). Thyroid-stimulating activity was also detected in 11 (28.9%) of 38 patients with Hashimoto's thyroiditis. However, the activity was considered to be due to TSH in the patients' sera, because it was completely abolished by pretreatment with anti-TSH antibodies. Serum TSH concentrations lower than 50 microU/ml did not affect the assay result. In Graves' disease after cessation of antithyroid drugs, 85.7% (12 of 14) of TSAb-positive patients relapsed, while 77.8% (14 of 18) of TSAb-negative patients remained in remission. Thus, the assessment of TSAb was useful as an index to predict prognosis.     

Evaluation of intraoperative radiation therapy for unresectable pancreatic cancer with FDG PET.

This investigation was undertaken to evaluate 18F-labeled fluorodeoxyglucose (FDG) PET in monitoring patients after intraoperative radiotherapy (IORT) for unresectable pancreatic cancer and to compare its usefulness with CT. METHODS: FDG PET was performed in 12 consecutive unresectable ductal adenocarcinoma patients before (n = 12) and after IORT (0.7-11.9 mo, n = 14). In the follow-up period, FDG PET results after IORT were divided into three groups: early (0-2.0 mo after IORT, n = 7), intermediate (2.1-4.0 mo, n = 5) and delayed period (4.1 mo or later, n = 2). FDG uptake at 60 min after injection of 185 MBq FDG under fasting conditions was analyzed with standardized uptake value (SUV). Three parameters, the highest SUV in the tumor, the area of tumor showing SUV of more than 2.0 and the average SUV in the tumor area were calculated. Ratios of each parameter after IORT to that before IORT were defined as residual uptake ratio (RUR)-1, -2 and -3, respectively. Tumor regression after IORT was evaluated with CT as tumor size ratio (TSR) every 2 mo. RESULTS: Results of RUR-1 and -3 were consistent with tumor size measured by CT. They decreased in 10 patients with partial response and increased in 2 patients with no change, although these 2 patients had abscesses. RUR-3 decreased consistently as 0.65+/-0.33 in 2 mo, 0.51+/-0.39 in 4 mo and 0.24 in 4 mo or later after IORT, respectively. RUR-1 decreased in early period, but demonstrated no change through the remaining periods. There were discrepancies between the results of RUR-2 and those of the other RURs. CT results revealed a slow decrease in tumor size, because TSR was 0.91 +/-0.10, 0.76+/-0.11 and 0.70+/-0.18 in 2, 4 and 6 mo after IORT, respectively. RUR-3 was smaller than TSR at 2 mo (P < 0.05) and 4 mo (P = 0.056). These results indicate that the measurement of the average SUV in the tumor area with FDG PET could evaluate the local response of pancreatic cancer after IORT earlier and more markedly than with CT. CONCLUSION: FDG PET was useful in monitoring patients after IORT, because the decrease of metabolism in pancreatic tumor could be detected earlier than the decrease in tumor size.     

Glucose metabolism and rate constants in Alzheimer''s disease examined with dynamic positron emission tomography scan

Glucose metabolic rate constants in patients with Alzheimer's disease were analyzed using dynamic positron emission tomography with [18-F] fluoro-2-deoxyglucose (FDG). The cerebral metabolic rate of glucose (CMRG) was calculated using obtained rate constants, as well as the autoradiographic method. The half-life and distribution volume of FDG between the blood and the brain tissue were also calculated from obtained metabolic rate constants. The most severely affected metabolic step was the phosphorylation of glucose in the parietotemporal regions. The distribution volume of FDG showed no remarkable deviation from normal controls, while the half-life of FDG was found to be longer in the parietal and temporal regions. The CMRG from rate constants and that from the autoradiographic method showed no remarkable differences.     

Orthostatic posture affects brain hemodynamics and metabolism in cerebrovascular disease patients with and without coronary artery disease: a positron emission tomography study

To investigate whether a physiological change in the orthostatic condition is associated with a deterioration of cerebrovascular and metabolic homeostasis in patients with neurocardiovascular compromises, we examined 10 patients with unilateral carotid artery occlusive disease (CVD), 6 CVD patients with coronary artery disease (CVDC), and 10 healthy subjects scanned twice under supine and sitting conditions by positron emission tomography (PET). Repeated measures analysis of variance showed significant reductions in regional cerebral blood flow (rCBF) and cerebral oxygen metabolism (rCMRO2) and tendency of increase in oxygen extraction fraction (OEF) in the affected-side parietal cortex during assuming of upright posture in the CVDC group, and there was a significant OEF increase to maintain rCMRO2 constant during sitting in the CVD counterpart. In this ischemic region, there were negative correlations between changes in OEF and rCBF in the CVD (P < 0.05) and CVDC groups (P < 0.01). Postural reductions in rCBF and CMRO2 in the parietal region were significantly greater in the CVDC group than those in the CVD group. While rCBF remained constant with mean arterial blood pressure (MABP) in healthy subjects, an rCBF reduction was found in the affected parietal cortex in proportion to the upright posture-induced MABP decrease in the CVDC group. These results indicate that patients suffering from both cerebral and coronary artery diseases may be at greater risk of deterioration of local perfusion pressure and metabolic regulation in the hemodynamically susceptible brain region during upright posture.     

Conventional and dual competitive binding analyses of thyroxine using the Thyopac-4 kit

A simple method is described for the simultaneous determinations of thyroxine and the effective thyroxine ratio (ETR) using a single kit of Thyopac-4. Thyopac ETR values obtained were 1.00 +/- 0.03 for normal subjects; 1.22 +/- 0.11 for hyperthyroid; 0.87 +/- 0.04 for hypothyroid; and 1.02 +/- 0.05 for pregnant women. Cases with TBG deficiency and the nephrotic syndrome indicated normal values. The value (x) was correlated significantly (gamma = + 0.961) with the free Thyopac index (y), representing a regression equation of y = 71.7x(2) - 88.4x + 24.2. Thyopac ETR was shown to be useful in differentiating normal thyroid states from abnormal, irrespective of changes in T(4)-binding globulin (TBG). Further, the T(4) value obtained simultaneously made it possible to detect changes in the TBG level by noting an inconsistent value for the effective thyroxine ratio.