WorldWideScience
 
 
3

Quantification of cardiac function with multislice spiral CT using retrospective EKG-gating: comparison with MRI  

International Nuclear Information System (INIS)

Purpose: To quantify left ventricular function derived from retrospectively ECG-gated multislice spiral CT (MSCT) data sets in comparison to MRI. Materials and Methods: In 16 patients (14 males, 2 females, mean age 56.8 #+-# 11.5 years), retrospectively ECG-gated MSCT angiography of the coronary arteries and breath-hold steady state free precession cine MRI were performed. From MSCT data-sets, 20 axial image series were reconstructed every 5% of the RR interval. Multiplanar images were reformatted in the short axis orientation from axial images. End-systolic and end-diastolic images were selected. From these images end-systolic volume (ESV), end-diastolic volume (EDV) and stroke volume (SV) as well as the ejection fraction (EF) and myocardial mass (MM) were determined using the Simpson's method and compared with MRI. Furthermore, image quality was assessed for both imaging modalities using a four point grading scale. ...

2003-01-01

4

The accuracy and reverse effects of thallium myocardial SPECT using adenosine triphosphate loading in the diagnosis of coronary artery disease. Comparison with other loading methods semiquantitatively  

Energy Technology Data Exchange (ETDEWEB)

The adverse effects and diagnostic accuracy of thallium-201 myocardial SPECT after intravenous infusion of adenosine triphosphate (ATP) were studied and compared with SPECT examinations with other type of loading. The subjects of the study were 147 patients with or without coronary artery disease, who underwent some type of loading SPECT and coronary arteriography (CAG) within 30 days. Myocardial ischemia was evaluated qualitatively in SPECT and was compared with CAG for the diagnostic accuracy of coronary artery disease. The degree of myocardial uptake defect was also calculated semiquantitatively using visual scoring method and compared with coronary artery severity score. The adverse effects occurred in 46.7% of ATP loading SPECT which was more frequent that DIP loading SPECT, but all of them were ...

1999-09-01

5

Correlation of myocardial TC-99m-MIBI perfusion SPECT with coronary angiography in Namazi hospital  

International Nuclear Information System (INIS)

Coronary heart disease is the leading cause of death specially among elderly. Coronary angiography is the best diagnostic method in the patients, but is unfortunately an invasive procedure with its inherent risks. Myocardial perfusion scan is a noninvasive and sensitive method for evaluation of Coronary artery disease and is suggested by many investigators in recent years. In this study, 64 patients who had a Tc99m-MIBI SPECT myocardial perfusion study at our department, underwent coronary angiography within 4 months. Correlation of the methods revealed that SPECT Tc99m -MIBI had a high sensitivity and specificity in our hand, which is comparable with international findings.

2004-04-27

6

Should coronary angiography be the gold standard? A study correlating thallium myocardial scintigraphy, translesional pressure gradient and percent stenosis  

International Nuclear Information System (INIS)

Coronary angiography provides anatomical information whereas thellium myocardial scintigraphy measures resistive tissue perfusion. Because of this fundamental difference. The authors question the validity of using coronary angiography as the gold standard to judge thellium myocardial scintigraphy. The authors studied 20 patients undergoing elective percutaneous coronary angioplasty who fulfilled the following criteria: (1) history of chest pain; (2) angiographically significant single vessel disease (>50% stenosis); (3) no prior myocardial infarction. All patients underwent maximal exercise thallium single photon emission computed tomography (T1-SPECT). Tl-SPECT was scored visually according to a 0 to 3 scale (0=absent uptake; 1=markedly decreased uptake; 2=minimally decreased uptake; 3=normal uptake). Translesional gradient and percent stenosis were measured before and after ...

1985-06-02

7

Simultaneous assessment of left ventricular function from gated myocardial perfusion SPECT. Utility of QGS (Quantitative Gated SPECT) program  

International Nuclear Information System (INIS)

Quantitative gated SPECT (QGS) was evaluated in 7 normal volunteers and 31 patients with cardiac diseases. Adequate cut off value of a prefilter was 0.45. In phantom, the left ventricular volume value was 93.9% of determined value by 180-degree projection in L type and 98.8% by 360-degree projection in opposed type. In normal volunteers, LVEF measured by QGS program related to value by first pass method. As for functional map, regional EF and wall motion decreased at the septum side, and wall thickening at base side of heart. Good correlation was recognized (p<0.0001) between blood flow image and functional map (regional EF and wall thickening). In 20 cases of acute myocardial infarction, lesion was detected conspicuously in regional EF and wall motion. The accuracy of coronary arterial stenosis improved in functional map (regional EF 92%, wall motion 92% and wall thickening 88%). In particular, the accuracy of 3 rami lesion was 100% in ...

1998-08-01

8

[sup 123]I-MIBG myocardial scintigraphy in diabetic patients. Relationship with [sup 201]Tl uptake and cardiac autonomic function  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this paper is to investigate the influence of diabetic myocardial damage (suspected myocardial damage; SMD) diagnosed by [sup 201]Tl-SPECT and diabetic cardiac autonomic neuropathy (AN) on myocardial MIBG uptake in patients with NIDDM. Eighty-seven diabetic patients divided into four subgroups: 23 with SMD (+) AN (+); 19 with SMD (+) AN (-); 27 with SMD (-) AN (+); 18 with SMD (-) AN (-), and 10 controls were studied. Both planar and SPECT images were taken at 30 minutes (early) and 3 hours (delayed) after [sup 123]I-MIBG injection. The heart to mediastinum uptake ratio (H/M) and washout ratio of [sup 123]I-MIBG (WR) were obtained from both planar images. Similarly, the difference between the [sup 201]Tl image and the [sup 123]I-MIBG image in the total uptake score (TUS) was taken as the difference in the total uptake score ([Delta]TUS) representing cardiac ...

1998-12-01

9

The influence of different SPECT reconstruction algorithms on cardiac ischemia with the use artificial neural networks  

International Nuclear Information System (INIS)

The aim of the study was the attempt to evaluate the influence of two different methods of cardiac perfusion SPECT reconstruction (FBP and ITW) on clinical efficacy in diagnosing the coronary artery disease as well as the cardiac ischemia detection in three areas of heart vascularized by main coronary arteries: LAD, LCX and RCA with the use of artificial neural networks (ANN). The study was performed retrospectively with the use of the diagnostic image records as well as clinical dataset of 43 patients. Myocardial perfusion stress/rest SPECT study and X-ray coronarography data were evaluated for each patient. The results of coronary angiography were considered the reference method. The cardiac SPECT data were reconstructed using the two different methods: filtered backprojection (FBP) and iterative Wallis method (ITW). The local perfusion deficits denominated in stress and rest study in three main ...

10

Cold pressor test myocardial perfusion SPECT as a predictor of the development of ischemia at exercise in the follow up of asymptomatic patients with moderate cardiovascular risk  

International Nuclear Information System (INIS)

Introduction: Previous studies have published the correlation between myocardial perfusion SPECT (MP) during cold pressor test (CPT) and intracoronary acetylcholine and its usefulness as independent marker of endothelial dysfunction (ED). Objective: To analyze the incidence of positivization of MP exercise studies in the follow up of asymptomatic patients with moderate cardiovascular risk (CV) and ED detected by PF. Material and Methods: Of 301 patients of the PARADIGMA Registry (normal exercise MP SPECT and clinical probability < 20% of events at 10 years [moderate risk by Framingham index]) 55 had positive PF (+) (18.3%). Prospectively and consecutively, 15 asymptomatic patients with PF (+), and a control group (CG) of 15 patients with negative PF, with paired sex, age and coronary risk factors (CRF), that accomplished a 12 #+-# 2 months follow up, and that underwent a new exercise and resting MP ...

11

Individually weight-adapted examination protocol in retrospectively ECG-gated MSCT of the heart  

Energy Technology Data Exchange (ETDEWEB)

The standard protocol in multislice spiral CT (MSCT) angiography for coronary arteries with fixed tube current-time settings leads to an overexposure and thus to an unnecessary high radiation dose in patients with lower weight when compared to heavier patients. The purpose of this study was to estimate the effect of reducing the radiation dose by adapting the tube current-time settings individually. Fifty patients underwent retrospectively ECG-gated MSCT of the heart. In 25 patients (group A{sub 1}) a standard protocol with constant tube current-time settings was used (4 x 1-mm collimation, 120 kV, 400 mAs{sub eff}). Subsequently, artificial image noise was added to the data of these patients simulating a directive for weight-adapted tube current-time settings (group A{sub 2}). In the other 25 patients (group B) an alternative protocol with individually weight-adapted tube current-time settings was applied. The data of all groups were evaluated by a regression ...

2003-12-01

12

Individually weight-adapted examination protocol in retrospectively ECG-gated MSCT of the heart  

International Nuclear Information System (INIS)

The standard protocol in multislice spiral CT (MSCT) angiography for coronary arteries with fixed tube current-time settings leads to an overexposure and thus to an unnecessary high radiation dose in patients with lower weight when compared to heavier patients. The purpose of this study was to estimate the effect of reducing the radiation dose by adapting the tube current-time settings individually. Fifty patients underwent retrospectively ECG-gated MSCT of the heart. In 25 patients (group A_1) a standard protocol with constant tube current-time settings was used (4 x 1-mm collimation, 120 kV, 400 mAs_e_f_f). Subsequently, artificial image noise was added to the data of these patients simulating a directive for weight-adapted tube current-time settings (group A_2). In the other 25 patients (group B) an alternative protocol with individually weight-adapted tube current-time settings was applied. The data of all groups were evaluated by a regression analysis. The ...

2003-12-01

13

[sup 123]I-MIBG myocardial scintigraphy in diabetic patients. Association with autonomic neuropathy  

Energy Technology Data Exchange (ETDEWEB)

[sup 123]I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy was performed in 20 diabetic patients (NIDDM) and 8 control subjects to investigate the association between clinical autonomic nerve dysfunction and myocardial accumulation of MIBG. We used coefficient variance of R-R interval (CV[sub R-R]) as a index of the autonomic neuropathy and categorized diabetes into two groups (CV[sub R-R][>=]2.0: non-autonomic neuropathy. CV[sub R-R]<2.0: autonomic neuropathy). In planar imaging studies, heart to mediastinum MIBG uptake ratio (H/M) was calculated on both early and delayed images. The washout ratio of [sup 123]I-MIBG in the heart (%WR) was also obtained using myocardial tracer activity on the both images. Mean value of these indices in diabetic group did not reveal any significant difference with the value in the control group. On the SPECT images, low uptake was observed in the ...

1994-09-01

14

Myocardial perfusion SPECT in patients after myocardial infarction: Comparison of "2"0"1Tl and dual-isotope protocol (rest "2"0"1Tl/stress "9"9"mTc tetrofosmin)  

International Nuclear Information System (INIS)

The diagnostic accuracy is compared of the dual-isotope protocol and the conventional "2"0"1Tl protocol, for detection of the coronary artery disease (CAD) using data on a total of 69 patients after myocardial infarction (MI). The "2"0"1Tl protocol was used to examine 44 patients, the dual-isotope protocol was used with 25 patients. All patients were examined by coronarography; a narrowing of the artery by more than 50 % was considered significant for CAD. The sensitivity, specificity and diagnostic accuracy was 97.7 %, 100 % and 97.7 % resp. for the "2"0"1Tl protocol, and 95.2 %, 75 % and 92 % resp. for the dual-isotope protocol. A higher diagnostic accuracy of the dual-isotope protocol has not been proven, and the "2"0"1Tl protocol continues to be used for examinations of patients after MI

1998-08-01

15

Cardiac transplantation. Value of computed tomography  

International Nuclear Information System (INIS)

In 9 over 12 patients who underwent cardiac transplantation computed tomography was performed. In 5 of them CT was obtained also before the surgical treatment. In all patients angio-CT technique was performed, while the ECG-gated technique was employed only before surgery. CT shows changes in morphology of both atria but over all of the right one, and rotation of the heart on the longitudinal axis. The conditions of the pericardium are particulary well demonstrated: in 5 cases pericardial effusion was observed, 3 times localized and 2 times diffuse. Only in 1 patient a small thrombus in the right atrium was demonstrated. CT allows the possibility to obtain simultaneously information on mediastinum, lung and pleura. Pleural effusion, pulmonary infections and mediastinal complications are easily demonstrated.

1986-01-01

16

{sup 99m}TC tetrofosmin cardiac tomography after nitrate administration in patients with coronary artery disease and left ventricular dysfunction; Tomografia cardiaca {sup 99m}Tc tetrofosmina dopo somministrazione di nitrati in pazienti con cardiopatia ischemica e disfunzione ventricolare sinistra  

Energy Technology Data Exchange (ETDEWEB)

The work examines twenty-two patients with coronary artery disease, previous myocardial infarction and LV dysfunction, using the technetium-99m ({sup 99m}Tc) tetrofosmin (SPECT) associated with nitrate administration in the detection of hypoperfused but still viable myocardium. The method allows the detection of this disease. [Italian] Il lavoro analizza i risultati degli esami condotti su 22 pazienti con cardiopatia ischemica cronica e ridotta funzione ventricolare sinistra sottoposti a tomografia computerizzata con emissione di fotone singolo (SPECT) cardiaca con tecnezio-99m ({sup 99m}Tc) tetrofosmina associata alla somministrazione di nitrati nella differenziazione tra tessuto miocardico ipoperfuso ma ancora vitale e tessuto miocardico necrotico. La metodologia usata consente di identificare la presenza di tessuto miocardico vitale in territori vascolari severamente ipoperfusi.

2000-04-01

18

Non cardiopatic and cardiopatic beta thalassaemic patients: quantitative and qualitative cardiac iron deposition evaluation with MRI; Pazienti {beta} talassemici non cardiopatici e cardiopatici: valutazione quantitativa e qualitativa del deposito di ferro cardiaco con RM  

Energy Technology Data Exchange (ETDEWEB)

Purpose: Cardiomyopathy is one of the major complications of {beta} thalassaemia major as a result of transfusion iron overload. The aim of our study is to evaluate with MR if there is any difference of iron deposition signal intensity (SI) or distribution between non-cardiopatic and cardiopatic thalassaemic patients in order to establish if there is a relationship between cardiopathy and iron deposition. Materials and methods: We studied 20 patients affected by {beta} thalassaemia major, of whom 10 cardiopatic and 10 non-cardiopatic, and 10 healthy volunteers as control group. Serum ferritin and left ventricular ejection fraction were calculated in thalassaemic patients. All patients were examinated using a 1.5 MR unit with ECG-gated GE cine-MR T2*-weighted, SE T1-weighted and GE T2*-weighted sequences. In all cases, using an adequate ROI, the myocardial and skeletal muscle signal intensity (SI), the myocardial/skeletal ...

2005-02-01

19

The present state of nuclear medicine practice in Japan; A report of the 3rd nationwide survey in 1992  

Energy Technology Data Exchange (ETDEWEB)

The Subcommittee for Surveillance of Nuclear Medicine Practice has implemented a survey for actual nuclear medicine practice in Japan every 5 years. This article reports on the third survey implemented during a one-month period in June 1992. Questionnaires were sent to all 1256 facilities employing radiopharmaceuticals in routine practice, and 1162 (92.5%) answered. In vivo nuclear medicine examinations per day were performed in 6600 cases. SPECT accounted for 19.4%, as compared with 7.1% in the 1987 survey. According to organs, the frequency of examination for the cerebrospinal region was 3.2 and 2.2 times higher than that in the 1982 and 1987 surveys, respectively, whereas for the thyroid gland it was 0.6-fold and 0.7-fold that of these surveys. The proportion of bone scintigraphy was the highest (24.5%), followed by tumor scintigraphy (14.1%) and myocardial scintigraphy (11.9%). The frequency of myocardial and cerebral ...

1993-09-01

20

Altered myocardial substrate metabolism is associated with myocardial dysfunction in early diabetic cardiomyopathy in rats: studies using positron emission tomography  

UK PubMed Central (United Kingdom)

BackgroundIn vitro data suggest that changes in myocardial substrate metabolism may contribute to impaired myocardial function in diabetic cardiomyopathy (DCM)....Full Text Available

 
 
 
 
21

MRI-based N-staging in esophageal cancer  

International Nuclear Information System (INIS)

Purpose: For planning the therapeutic strategies and estimating the prognosis in esophageal cancer, N-staging is very important. To date, MRI still is of minor importance as imaging modality of the mediastinum despite promising developments in the past, like ECG-gating or 'averaging' sequences, e.g. LOTA (Long-term averaging), which facilitate mediastinal and thoracic MR-imaging. In a prospective approach, the value of MRI based N-staging was examined with respect to LOTA-sequences. Material and Methods: Within from weeks prior to esophagectomy, standardized MRI of the esophagus was performed in 15 patients (10 squamous-cell-carcinomas and 5 adenocarcinomas) using a 1.5 T whole body scanner. Imaging quality was classified based on depiction of aortic wall or tracheal wall layers. Criteria for malignant infiltration were a diameter of more than 15 mm or a round appearance of a lymph node together with GD-DTPA enhancement. All data were blinded and separately read by ...

2002-10-01

22

Impact of the Metabolic Syndrome on the Clinical Outcome of Patients with Acute ST-Elevation Myocardial Infarction  

UK PubMed Central (United Kingdom)

We sought to determine the prevalence of metabolic syndrome (MS) in patients with acute myocardial infarction and its effect on clinical outcomes. Employing data from the Korea Acute Myocardial Infarction...Full Text Available

2010-10-01

23

The usefulness of CBF brain SPECT in forensic medicine: the civil law codes cases. A description of four cases  

International Nuclear Information System (INIS)

The aim of this report was to assess the usefulness of cerebral blood flow (CBF) scanning utilising the SPECT technique in forensic medicine cases in the area of civil law cases. CBF SPECT scanning was performed in four patients utilising "9"9"mTc-ECD and a triple-head gammacamera. In the analysis both the asymmetry index and cerebellar normalisation were applied. Reference values were obtained by studying 30 healthy volunteers. In those cases CBF SPECT scanning played an important role in forensic argument. It influenced the sentence and the amount of financial compensation. CBF SPECT scanning may provide valuable information in forensic medicine argument in civil law cases, but only when taken together with psychometric tests and other neuroimaging methods (CT, MRI). The value of CBF SPECT scanning alone may be limited in judicial proceedings. (author)

24

Review of Cost-Effectiveness Analysis of Medical Treatment For Myocardial Infarction  

UK PubMed Central (United Kingdom)

Objectives:Myocardial infarction (MI) is a leading cause of death in both the industrialized and developing countries globally. The economic evaluation of MI is undertaken...Full Text Available

2011-04-01

25

Arterial and Venous Thrombosis in Cancer Patients  

UK PubMed Central (United Kingdom)

The most frequent ultimate cause of death is myocardial arrest. In many cases this is due to myocardial hypoxia, generally arising from failure of the coronary macro- and microcirculation to deliver...Full Text Available

26

MULTIMODALITY IMAGING: BEYOND PET/CT AND SPECT/CT  

UK PubMed Central (United Kingdom)

Multimodality imaging with PET/CT and SPECT/CT has become commonplace in clinical practice and in preclinical and basic medical research. Do other combinations of imaging modalities have a similar...Full Text Available

2009-09-01

27

Limitations of Tc99m-MIBI-SPECT Imaging Scans in Persistent Primary Hyperparathyroidism  

UK PubMed Central (United Kingdom)

BackgroundIn primary hyperparathyroidism (PHPT) the predictive value of technetium 99m sestamibi single emission computed tomography (Tc99m-MIBI-SPECT) for localizing pathological...Full Text Available

2011-01-01

28

Clinical value of SPECT/CT for evaluation of patients with painful knees after total knee arthroplasty- a new dimension of diagnostics?  

UK PubMed Central (United Kingdom)

BackgroundThe purpose of our study was to evaluate the clinical value of hybrid SPECT/CT for the assessment of patients with painful total knee arthroplasty (TKA).MethodsTwenty-three...Full Text Available

30

Myocardial metabolic regulation through peroxisome proliferator-activated receptor alpha after myocardial infarction  

UK PubMed Central (United Kingdom)

Although peroxisome proliferator-activated receptor alpha (PPARα) is closely associated with myocardial fatty acid metabolism, the pathophysiological role of PPARα in myocardial infarction...Full Text Available

2003-01-01

31

Localization of "2"0"3Pb-chloride in myocardial infarction  

International Nuclear Information System (INIS)

... AND NUCLEAR MEDICINE biological localization cardiovascular diseases

33

Role of nuclear medicine and magnetic resonance imaging in cardiac diagnostics; Rolle der nuklearmedizinischen Verfahren und der Magnetresonanztomographie in der kardialen Diagnostik  

Energy Technology Data Exchange (ETDEWEB)

Nuclear medicine and magnetic resonance imaging (MRI) are widely used in cardiac diagnostics. Both techniques have been carefully evaluated and are equivalent for the assessment of regional and global wall motion as well as the evaluation of ejection fraction and cardiac volumes, though MRI is herein currently seen as gold standard. For evaluation of myocardial perfusion, extensive data exist for nuclear imaging, that, next to high diagnostic accuracy for evaluation of coronary artery disease, show incremental prognostic information and allow for independent risk stratification. Because of rapid technical advance, myocardial perfusion imaging has also become feasible with cardiac MRI. Results of recent studies are promising, but the data are few compared to perfusion scintigraphy. For viability assessment in patients with ischemic cardiomyopathy, positron emission tomography (PET) with FDG is currently seen as gold standard. However, single ...

2003-12-01

34

Use of clopidogrel in the reduction of myocardial damage during percutaneous coronary intervention  

UK PubMed Central (United Kingdom)

It is estimated that approximately a quarter of patients undergoing coronary intervention may have significant post-procedural creatinine (CK)/creatinine kinase myocardial band (CK-MB) elevations and...Full Text Available

2009-01-01

35

Trial of early nifedipine in acute myocardial infarction: the Trent study.  

UK PubMed Central (United Kingdom)

Over 30 months 9292 consecutive patients admitted to nine coronary care units with suspected myocardial infarction were considered for admission to a randomised double blind study comparing the effect...Full Text Available

1986-11-08

36

The zebrafish heart regenerates after cryoinjury-induced myocardial infarction  

UK PubMed Central (United Kingdom)

BackgroundIn humans, myocardial infarction is characterized by irreversible loss of heart tissue, which becomes replaced with a fibrous scar. By contrast, teleost fish and urodele...Full Text Available

37

The Trade-Off between Costs and Outcomes: The Case of Acute Myocardial Infarction  

UK PubMed Central (United Kingdom)

ObjectiveTo investigate and to quantify the relationship between hospital costs and health outcomes for patients with acute myocardial infarction (AMI) in Veterans Health Administration...Full Text Available

2010-12-01

38

Routine invasive management after fibrinolysis in patients with ST-elevation myocardial infarction: a systematic review of randomized clinical trials  

UK PubMed Central (United Kingdom)

BackgroundPatients with ST-elevation myocardial infarction (STEMI) treated with fibrinolysis are increasingly, and ever earlier, referred for routine coronary angiography and where...Full Text Available

39

Motor Vehicle Licences and Myocardial Infarction  

UK PubMed Central (United Kingdom)

Health standards for truck drivers are higher than those for the general motoring public, particularly concerning the need to restrict driving following recovery from a myocardial infarction. An analysis...Full Text Available

1984-12-01

40

Identification of Cardiac Myosin-binding Protein C as a Candidate Biomarker of Myocardial Infarction by Proteomics Analysis*  

UK PubMed Central (United Kingdom)

Acute myocardial infarction (AMI) is a common cause of death for which effective treatments are available provided that diagnosis is rapid. The current diagnostic gold standards are circulating cardiac...Full Text Available

2009-12-01

 
 
 
 
41

Efficacy and Safety of Low-Molecular-Weight Heparins As An Adjunct to Thrombolysis in Acute ST-Elevation Myocardial Infarction  

UK PubMed Central (United Kingdom)

A 48-hour course of intravenous unfractionated heparin (UFH) is the standard of treatment in conjunction with fibrin-specific thrombolysis in ST-elevation myocardial infarction (STEMI). In recent trials,...Full Text Available

2008-02-01

42

Effects of norepinephrine infusion on myocardial high-energy phosphate content and turnover in the living rat.  

UK PubMed Central (United Kingdom)

Using 31P-nuclear magnetic resonance, we studied the relationship between myocardial high-energy phosphate content and flux values for the creatine kinase reaction in the living rat under inotropic...Full Text Available

1987-06-01

43

Anatomical Reasons for the Discrepancies in Atrioventricular Block after Inferior Myocardial Infarction with and without Right Ventricular Involvement  

UK PubMed Central (United Kingdom)

The incidence of arrhythmias after acute myocardial infarction of the inferior wall varies with the affected segment and increases when there is right ventricular involvement. This paper provides a...Full Text Available

2009-01-01

44

A New Efficient Method of Topical Cooling and Rewarming of the Myocardium  

UK PubMed Central (United Kingdom)

Profound myocardial hypothermia (below 17° C, and more often around 12° C) is imperative in myocardial protection while the aorta is cross-clamped. Based on our experience in...Full Text Available

1985-12-01

45

Integration of SPECT with CT to plan radiotherapy fields. n application to conformal irradiation for lung carcinoma  

International Nuclear Information System (INIS)

Single photon emission computed tomography (SPECT) of lung perfusions permits to map functioning lung parenchyma with higher sensitivity than CT. Delivering higher radiations doses it used to increase local control in lung carcinoma; this strategy is based on radiobiological and clinical studies. Lung parenchyma is a dose-limiting tissue in patients irradiated for lung cancer. Functional mapping based on SPECT and CT findings permits to design radiation beams such as to minimize irradiation of functioning lung.

1999-04-01

46

Transesophageal echo to help percutaneous closure of ventricular septal defect post acute myocardial infarction  

British Library Electronic Table of Contents (United Kingdom)

Ventricular septal defect after acute myocardial infarction (AMI) is a complication associated with poor outcome in the absence of intervention. We report a case of successful TEE guided transcatheter closure of a post myocardial infarction (MI) ventricular septal defect (VSD) with an Amplatzer occluder in a 79 years old male with cardiogenic shock.

2011-01-01

47

Detection of acute myocardial infarction in spontaneously hypertensive rats by /sup 99m/Tc-Pyrrolidino methyl tetracycline  

Energy Technology Data Exchange (ETDEWEB)

The myocardial infarct induced by isoproterenol in spontaneously hypertensive rats accumulates higher activities of /sup 99/sup(m)Tc-PM tetracycline compared with the cardiac infarct in normotensive rats caused by the same method. The isoproterenol model of the myocardial necrosis was induced in intact rats without opening the thorax and is a convenient method for experimental radioisotope studies.

1983-01-01

48

Quantitative evaluation of simultaneous reconstruction with model-based crosstalk compensation for 99mTc?123I dual-isotope simultaneous acquisition brain SPECT  

UK PubMed Central (United Kingdom)

A model-based method has been previously developed to estimate and compensate for the crosstalk and downscatter contamination in simultaneous 123I∕99mTc dual-isotope SPECT...Full Text Available

2009-06-01

49

Proceedings of clinical SPECT [single photon emission computed tomography] symposium  

International Nuclear Information System (INIS)

It has been five years since the last in-depth American College of Nuclear Physicians/Society of Nuclear Medicine Symposium on the subject of single photon emission computed tomography (SPECT) was held. Because this subject was nominated as the single most desired topic we have selected SPECT imaging as the basis for this year's program. The objectives of this symposium are to survey the progress of SPECT clinical applications that have taken place over the last five years and to provide practical and timely guidelines to users of SPECT so that this exciting imaging modality can be fully integrated into the evaluation of pathologic processes. The first half was devoted to a consideration of technical factors important in SPECT acquisition and the second half was devoted to those organ systems about which sufficient clinical SPECT imaging data are available. With ...

1986-09-22

50

Preparation and radiolabeling of IBZM: a potential D-2 specific brain imaging agents for SPECT  

International Nuclear Information System (INIS)

In developing new receptor-site specific brain imaging agents labeled with I-123 for single photon emission computed tomography (SPECT), an analog of raclopride, 3-["1"2"5I]-iodo-N-[(1-ethyl-2-pyrrolidinyl)-methyl]-2-hydroxy-6-me-thoxy benzamide (IBZM), was prepared using a method similar to that reported for raclopride and its derivatives. (author).

51

Perfusion impairments in children with reactive attachment disorder (RAD) on "9"9"mTc-ECD brain SPECT: comparison with MR findings  

International Nuclear Information System (INIS)

This study aimed to reveal that severe disturbance of attachment relationship with primary care-giver can affect functional and anatomical brain development by measuring cerebral perfusion on "9"9"mTc-ECD brain SPECT and correlative MRI. We included 18 children aged 31 to 76 months who met the diagnostic criteria of RAD as defined in DSM-IV and ICD-10 and SSP and CARS. "9"9"mTc-ECD SPECT was performed using CERASPECT. MRI was performed in all patients. SPECT data were visually assessed. 15 of 18 children had abnormal perfusion on SPECT, revealing decreased perfusion of Lt.thalamus (7/15) and Rt.thalamus (3/15), and bilateral thalami (5/15). Perfusion of basal ganglia was decreased in 8 children. Decreased perfusion of Lt. parietal area was seen in 2. Whereas, all patients had normal MR findings. Perfusion abnormalities involving thalamus, BG in most children with RAD were found in this study. These ...

2002-11-15

52

Clinical features and {sup 123}I-FP-CIT SPECT imaging in drug-induced parkinsonism and Parkinson's disease  

Energy Technology Data Exchange (ETDEWEB)

To determine clinical predictors and accuracy of {sup 123}I-FP-CIT SPECT imaging in the differentiation of drug-induced parkinsonism (DIP) and Parkinson's disease (PD). Several clinical features and {sup 123}I-FP-CIT SPECT images in 32 patients with DIP, 25 patients with PD unmasked by antidopaminergic drugs (PDu) and 22 patients with PD without a previous history of antidopaminergic treatment (PDc) were retrospectively evaluated. DIP and PD shared all clinical features except symmetry of parkinsonian signs which was more frequently observed in patients with DIP (46.9%) than in patients with PDu (16.0%, p<0.05) or PDc (4.5%, p<0.01). Qualitatively {sup 123}I-FP-CIT SPECT images were normal in 29 patients with DIP (90.6%) and abnormal in all patients with PD, and this imaging technique showed high levels of accuracy. DIP and PD are difficult to differentiate based on clinical signs. The precision of ...

2010-03-15

53

Serial Intravascular Ultrasound Analysis of the Impact of Myocardial Bridge on Neointimal Proliferation After Coronary Stenting in Patients with Acute Myocardial Infarction  

British Library Electronic Table of Contents (United Kingdom)

Background: Mechanisms underlying the association between myocardial bridge (MB)-stenting and in-stent restenosis (ISR) are still unclear. Objective: To assess the impact of MB on ISR using intravascular ultrasound (IVUS). Methods: In the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial, 100 left anterior descending artery (LAD) culprit lesions (79 treated with paclitaxel-eluting stents [PES] and 21 treated with bare metal stents) were imaged with serial IVUS immediately postprocedure and at 13 months. Results: At baseline the LAD stent extended into the MB segment beyond the culprit lesion in seven patients (MB-stent group). In the remaining 93 patients the LAD stent was implanted only in the culprit lesion without extending into t...

2010-01-01

54

Myocardial imaging in patients with Kawasaki disease. Exercise stress imaging and serial studies  

Energy Technology Data Exchange (ETDEWEB)

Thallium-201 myocardial imaging was performed in 80 children with coronary arterial lesions due to Kawasaki disease in order to assess the value of serial and exercise myocardial imagings. In eight of these children, abnormalities of the image were noted. Twenty children had serial thallium studies with an interval of three to 18 months, and five of these showed changes in the image including appearance of a new perfusion defect in one patient and improvement of perfusion defects in four. These changes of the myocardial image were correlated well with coronary angiographic findings obtained within a few days of the isotope studies. It was noted that the changes of the myocardial image were more frequently observed at relatively recent period recovered from Kawasaki disease. Exercise myocardial imaging using a bicycle ergometer was performed in eight children with coronary arterial ...

1982-06-01

55

Cardioprotection conferred by exercise training is blunted by blockade of the opioid system  

UK PubMed Central (United Kingdom)

OBJECTIVES:To investigate the effect of opioid receptor blockade on the myocardial protection conferred by chronic exercise and to compare exercise training with different strategies...Full Text Available

2011-01-01

56

Cardiac Enzymes, Renal Failure and Renal Transplantation  

UK PubMed Central (United Kingdom)

Diagnostic accuracy of the currently available serum markers of cardiac injury, such as myoglobin, creatine kinase and its myocardial isoform, are altered in patients with renal failure. It is shown...Full Text Available

2006-03-01

57

Evaluation of tilted cone-beam CT orbits in the development of a dedicated hybrid mammotomograph  

UK PubMed Central (United Kingdom)

A compact dedicated 3D breast SPECT-CT (mammotomography) system is currently under development. In its initial prototype, the cone-beam CT sub-system is restricted to a fixed-tilt circular rotation...Full Text Available

2009-06-21

58

Elevated BMI Is Associated With Decreased Blood Flow in the Prefrontal Cortex Using SPECT Imaging in Healthy Adults  

UK PubMed Central (United Kingdom)

Obesity is a risk factor for stroke and neurodegenerative disease. Excess body fat has been linked to impaired glucose metabolism, insulin resistance, and impulsivity and may be a precursor to decline...Full Text Available

2011-05-01

59

MRI-based N-staging in esophageal cancer; N-Staging des Oesophaguskarzinoms mittels MRT unter Verwendung von artefaktreduzierenden LOTA-Sequenzen  

Energy Technology Data Exchange (ETDEWEB)

Purpose: For planning the therapeutic strategies and estimating the prognosis in esophageal cancer, N-staging is very important. To date, MRI still is of minor importance as imaging modality of the mediastinum despite promising developments in the past, like ECG-gating or 'averaging' sequences, e.g. LOTA (Long-term averaging), which facilitate mediastinal and thoracic MR-imaging. In a prospective approach, the value of MRI based N-staging was examined with respect to LOTA-sequences. Material and Methods: Within from weeks prior to esophagectomy, standardized MRI of the esophagus was performed in 15 patients (10 squamous-cell-carcinomas and 5 adenocarcinomas) using a 1.5 T whole body scanner. Imaging quality was classified based on depiction of aortic wall or tracheal wall layers. Criteria for malignant infiltration were a diameter of more than 15 mm or a round appearance of a lymph node together with GD-DTPA enhancement. All data were blinded and ...

2002-10-01

60

Dopamine transporter density of the basal ganglia in children with attention deficit hyperactivity disorder assessed with I-123 IPT SPECT  

Energy Technology Data Exchange (ETDEWEB)

Attention deficit hyperactivity disorder (ADHD) has been known as psychiatric disorder in childhood associated with dopamine dysregulation. In present study, we investigated changes in dopamine transporter (DAT) density of the basal ganglias using I-123 N-(3-iodopropen-2-yl) -2-carbomethoxy-3beta-(4-chlorphenyl) tropane (I-123 IPT) SPECT in children with ADHD before and after methylphenidate treatment. Nine drug-naive children with ADHD and seven normal children were included in the study. We performed brain SPECT two hours after the intravenous administration of I-123 IPT and made both quantitative and qualitative analyses using the obtained SPECT data, which were reconstructed for the assessment of specific/nonspecific DAT binding ratios in the basal ganglia. All children with ADHD reperformed (123I)IPT SPECT after treatment with methylphenidate (0.7mg/kg/d) during about 8 weeks. ...

2003-08-01

 
 
 
 
61

Disagreements between central clinical events committee and site investigator assessments of myocardial infarction endpoints in an international clinical trial: review of the PURSUIT study  

UK PubMed Central (United Kingdom)

BackgroundLimited information has been published regarding how specific processes for event adjudication can affect event rates in trials. We reviewed nonfatal myocardial infarctions...Full Text Available

2001-01-01

62

Diagnosis of early human myocardial ischemic damage with electron probe microanalysis  

Energy Technology Data Exchange (ETDEWEB)

We determined the Na/K x-ray intensity ratio in frozen sections of myocardial tissues obtained at autopsy from patients who died from various causes, using electron probe analysis. We have been able to distinguish between the ischemically injured and normal cells. The method is simple, fast, and dependable even when the duration of ischemia is only 30 minutes.

1983-03-01

63

Associations of major bleeding and myocardial infarction with the incidence and timing of mortality in patients presenting with non-ST-elevation acute coronary syndromes: a risk model from the ACUITY trial  

UK PubMed Central (United Kingdom)

AimsTo evaluate the associations of myocardial infarction (MI) and major bleeding with 1-year mortality. Both MI and major bleeding predict 1-year mortality in patients presenting...Full Text Available

2009-06-01

64

Successful transcatheter coil embolization of coronary artery to left ventricular fistula associated with absent pulmonary valve with tricuspid atresia in early infancy.  

Science.gov (United States)

Transcatheter coil embolization for coronary artery to left ventricular fistula was successfully performed in a neonate. At 30 weeks' gestation, fetal echocardiography showed a hypoplastic right ventricle with intact ventricular septum, absent pulmonary valve, tricuspid atresia, and marked distension of the right coronary artery. After birth, the neonate had congestive heart failure and the electrocardiogram showed myocardial ischemic changes in the left ventricular area. Aortography showed a dilated right coronary artery arising from the ascending aorta and draining into the left ventricle. Transcatheter coil embolization was carried out on the 9th day after birth. Since the procedure, no myocardial ischemic changes have been detected. Transcatheter coil embolization is a useful therapy for coronary artery fistula associated with myocardial ischemia. PMID:15564713

2004-12-01

65

Plasma carotenoids and risk of acute myocardial infarction in the Singapore Chinese Health Study  

British Library Electronic Table of Contents (United Kingdom)

Background and aimModification of low-density lipoprotein due to oxidative stress is essential in the development of coronary atherosclerosis. Data of specific carotenoids except b-carotene on cardioprotective effects in humans are limited. Methods and resultsThis study examined the associations between plasma concentrations of specific carotenoids and incidence of acute myocardial infarction. The study included 280 incident cases of acute myocardial infarction and 560 matched controls nested within the Singapore Chinese Health Study, a prospective cohort of 63,257 Chinese men and women aged 45-74 years old enrolled in 1993-1998 in Singapore. Retinol and carotenoids in prediagnostic plasma were quantified using high-performance liquid chromatography. High levels of plasma b-cryptoxanthin a...

2011-01-01

66

PET and MRI in cardiac imaging: from validation studies to integrated applications  

International Nuclear Information System (INIS)

Positron emission tomography (PET) is the gold standard for non-invasive assessment of myocardial viability and allows accurate detection of coronary artery disease by assessment of myocardial perfusion. Magnetic resonance imaging (MRI) provides high resolution anatomical images that allow accurate evaluation of ventricular structure and function together with detection of myocardial infarction. Potential hybrid PET/MR tomography may potentially facilitate the combination of information from these imaging modalities in cardiology. Furthermore, the combination of anatomical MRI images with the high sensitivity of PET for detecting molecular targets may extent the application of these modalities to the characterization of atherosclerotic plaques and to the evaluation of angiogenetic or stem cell therapies, for example. This article reviews studies using MRI and PET in parallel to compare their performance in cardiac ...

2009-03-01

67

Lesion localization in patients with hyperparathyroidism using double-phase Tc-99m MIBI parathyroid scintigraphy  

International Nuclear Information System (INIS)

This study was performed to evaluate the diagnostic usefulness of double-phase Tc-99m MIBI parathyroid scintigraphy with single photon emission computed tomography (SPECT) in patients with hyperparathyroidism. We also evaluated the relationship between Tc-99m MIBI uptake and oxyphil cell contents in parathyroid glands. The subjects were 28 parathyroid glands of 10 patients who underwent Tc-99m MIBI parathyroid scintigraphy and parathyroidectomy for clinically suspected hyperparathyroidism. Early and delayed pinhole images were obtained at 15 minutes and 2 hours after injection of Tc-99m MIBI, and SPECT images were followed. The weight and oxyphil cell contents of parathyroid tissue were obtained from pathologic specimen, and the scintigraphic findings were compared with histopathology. In surgical histopathology, 6 parathyroid adenomas and 9 parathyroid hyperplasias were confirmed. The sensitivity, specificity, and positive predictive value of ...

1999-02-01

68

Evaluation of craniosynostosis surgery. Technetium-99m-HMPAO SPECT cerebral blood flow study in children with craniosynostosis  

International Nuclear Information System (INIS)

Premature fusion of multiple cranial sutures has been associated with increased intracranial pressure and the potential for mental impairment. Isolated craniosynostosis, however, is considered a benign condition primarily reconstructed for aesthetic purposes. A comparative analysis, to assess the differences between pre- and post operatory cerebral perfusion of patients who underwent surgery for simple cranisynostosis, was performed using single positron emission computed tomography ''SPECT'' Images. Cerebral blood flow studies were performed using "9"9"mTc-HMPAO SPECT in children with simple cranisynotoses. The subjects were 8 children with craniosynostosis (age, 2 months-9 years). Preoperative revealed regional hypovascularity in the cerebral hemisphere in 5 cases (62%). In 6 patients the cerebral blood flow normalized or increased after craniofacial reconstruction. We demonstrated the presence of regional hypovascularity in the cerebral ...

1998-09-01

69

Dopamine transporter density in the basal ganglia assessed with {sup 123}I-IPT SPECT in children with attention deficit hyperactivity disorder  

Energy Technology Data Exchange (ETDEWEB)

Attention deficit hyperactivity disorder (ADHD) is known as a psychiatric disorder in childhood associated with dopamine dysregulation. We investigated dopamine transporter (DAT) density in children with ADHD in the present study using {sup 123}I-IPT SPECT and postulated that an alteration in DAT density in the basal ganglia (BG) is responsible for dopaminergic dysfunction in children with ADHD. 9 durg-naive children with ADHD and 6 normal children were included in the study. We performed brain SPECT 2 hours after administration of {sup 123}I-IPT and made both quantitative and qualitative analyses for assessment of specific/nonspecific DAT binding ratio in the BG. We investigated the correlation between the severity scores of ADHD symptoms in children with ADHD assessed with ADHD rating scale and specific/nonspecific DAT binding ratio in the BG. Drug-naive children with ADHD showed a significantly incresed specific/nonspecific DAT binding ratio ...

2002-07-01

70

Utilization of Tc-99m-TBI as a myocardial perfusion agent in exercise studies: Comparison with Tl-201 thallous chloride and examination of its biodistribution in humans  

Energy Technology Data Exchange (ETDEWEB)

Twenty-four patients were studied with both /sup 201/Tl-thallus chloride and /sup 99m/Tc-TBI scintigraphy following exercise. Comparison of the two agents in detecting segmental myocardial ischemia and scar was made in 18 patients with evidence of coronary artery disease on /sup 201/Tl-thallous chloride scintigraphy. Agreement between the two studies was observed in 77% (125 of 162) of left ventricular segments, suggesting that /sup 99m/Tc-TBI can be used as a myocardial perfusion agent. Limitations were related to early high background activity from lungs and liver. The high lung activity and early myocardial redistribution within the 1st hour contributed to the failure of /sup 99m/Tc-TBI to detect 16 segmental defects seen in the immediate post-exercise thallous chloride scan. Persistently high liver activity additionally affected accurate interpretation in the left ventricular segments close to the diaphragm. Improvement ...

1986-10-01

71

The Aging Heart and Post-Infarction Left Ventricular Remodeling  

UK PubMed Central (United Kingdom)

Aging is a risk factor for heart failure, which is a leading cause of death world-wide. Elderly patients are more likely than young patients to experience a myocardial infarction (MI) and are...Full Text Available

2010-12-28

72

Spontaneous coronary artery dissection in the postpartum period: association with antiphospholipid antibody  

UK PubMed Central (United Kingdom)

Spontaneous coronary artery dissection (SCAD) is an extremely uncommon cause of myocardial infarction, occurring predominantly in women during or after pregnancy. The exact aetiology...Full Text Available

2004-09-01

73

Selective endothelin A-receptor blockade attenuates coronary microvascular dysfunction after coronary stenting in patients with type 2 diabetes  

UK PubMed Central (United Kingdom)

Background:Endothelin-1 may be involved in the development of diabetic microangiopathy. We studied the effect of endothelin-1 blockade on myocardial microcirculation during coronary...Full Text Available

2009-01-01

74

Segmentation of Myocardial Boundaries in Tagged Cardiac MRI Using Active Contours: A Gradient-Based Approach Integrating Texture Analysis  

UK PubMed Central (United Kingdom)

The noninvasive assessment of cardiac function is of first importance for the diagnosis of cardiovascular diseases. Among all medical scanners only a few enables radiologists to evaluate the local cardiac...Full Text Available

2009-01-01

75

Relation between regional and global systolic function in patients with ischemic cardiomyopathy after ?-Blocker therapy or revascularization  

UK PubMed Central (United Kingdom)

BackgroundTo assess the relationship between improved regional and global myocardial function in patients with ischemic cardiomyopathy in response to β-blocker therapy or...Full Text Available

76

Recent US Patterns and Predictors of Prevalent Diabetes among Acute Myocardial Infarction Patients  

UK PubMed Central (United Kingdom)

Background. Diabetes mellitus (DM) confers high vascular risk and is a growing national epidemic. We assessed clinical characteristics and prevalence of diagnosed DM among patients...Full Text Available

77

Pharmacological Prevention of Peri-, and Post-Procedural Myocardial Injury in Percutaneous Coronary Intervention  

UK PubMed Central (United Kingdom)

In recent years, percutaneous coronary intervention (PCI) has become a well-established technique for the treatment of coronary artery disease. PCI improves symptoms in patients with coronary artery...Full Text Available

2008-08-01

78

Percutaneous Management of a Long Saphenous Vein Graft Aneurysm: A Case Report and Review of Literature  

UK PubMed Central (United Kingdom)

Aneurysms of saphenous vein grafts are rare but can result in complications such as myocardial infarction or death. Percutaneous treatment has included a variety of approaches, including covered stents....Full Text Available

2009-01-01

79

Normal Coronary Artery Patient Presenting with Left Ventricular Aneurysm  

UK PubMed Central (United Kingdom)

Left ventricular aneurysm (LVA) is one of the most important complications of myocardial infarction LVA is strictly defined as a distinct area of abnormal left ventricular diastolic contour with systolic...Full Text Available

2011-01-01

 
 
 
 
81

Management of patients with unstable angina/non-ST-elevation myocardial infarction: a critical review of the 2007 ACC/AHA guidelines  

UK PubMed Central (United Kingdom)

Background:In 2007, the American College of Cardiology/American Heart Association (ACC/AHA) published new guidelines for the diagnosis and management of patients with unstable angina/non-ST...Full Text Available

2009-04-01

82

MRI Findings of Pericardial Fat Necrosis: Case Report  

UK PubMed Central (United Kingdom)

Pericardial fat necrosis is an infrequent cause of acute chest pain and this can mimic acute myocardial infarction and acute pericarditis. We describe here a patient with the magnetic resonance imaging...Full Text Available

2011-05-01

83

Lipotoxic heart disease in obese rats: Implications for human obesity  

UK PubMed Central (United Kingdom)

To determine the mechanism of the cardiac dilatation and reduced contractility of obese Zucker Diabetic Fatty rats, myocardial triacylglycerol (TG) was assayed chemically and morphologically. TG was...Full Text Available

2000-02-15

84

Left Main Stent Thrombosis Complicated by Eptifibatide-Induced Acute Thrombocytopenia  

UK PubMed Central (United Kingdom)

A 57-year-old man with a history of coronary artery disease and placement of an implantable cardioverter-defibrillator presented at our emergency room with an anterior ST-elevation myocardial infarction....Full Text Available

2011-01-01

85

Intravascular ultrasound to guide the management of intracoronary thrombus: a Case Report  

UK PubMed Central (United Kingdom)

Percutaneous coronary intervention can be associated with distal embolization of thrombotic material causing myocardial necrosis and infarction.We discuss the role of intravascular imaging to...Full Text Available

86

Features and Outcomes In Utero and after Birth of Fetuses with Myocardial Disease  

UK PubMed Central (United Kingdom)

Objectives. Ninety-one fetuses with dilated or hypertrophic cardiomyopathy (DCM, HCM) and myocarditis were studied. Results. Group 1 “DCM”...Full Text Available

2010-01-01

87

Elevated Cardiac Troponin I in Sepsis and Septic Shock: No Evidence for Thrombus Associated Myocardial Necrosis  

UK PubMed Central (United Kingdom)

BackgroundElevated cardiac troponin I (cTnI) is frequently observed in patients with severe sepsis and septic shock. However, the mechanisms underlying cTnI release in these patients...Full Text Available

88

Dietary Glycaemic Index, Dietary Glycaemic Load, and Incidence of Myocardial Infarction in Women  

UK PubMed Central (United Kingdom)

The association of dietary glycaemic index (GI) and glycaemic load (GL) with cardiovascular diseases has been examined in several populations with varying results. We tested the hypothesis that...Full Text Available

2010-04-01

89

Clinical utility of tissue Doppler imaging in patients with acute myocardial infarction complicated by cardiogenic shock  

UK PubMed Central (United Kingdom)

BackgroundEchocardiography is widely used in the management of patients with cardiogenic shock (CS). Left ventricular ejection fraction (EF) has been shown to be an independent predictor...Full Text Available

90

Clinical Application of Ischemic Preconditioning in the Elderly  

UK PubMed Central (United Kingdom)

A mild stress such as brief ischemic episodes may protect the heart from a successive and more prolonged myocardial ischemia (ischemic preconditioning). This phenomenon is considered a typical “hormetic...Full Text Available

91

Anxiety in Patients with Cardiac Disease.  

Science.gov (United States)

Anxiety may cause adverse outcomes through physiologic pathways in patients with cardiac disease. The purpose of this dissertation was to investigate anxiety and its correlates in persons with acute myocardial infarction (AMI) and heart failure (HF). The ...

2005-01-01

92

Analysis of myocardial time-activity curves of /sup 123/I-heptadecanoic acid. Pt. 1. Curve fitting  

Energy Technology Data Exchange (ETDEWEB)

Myocardial time-activity curves can be described by two or more parameters. To establish the optimal curve fitting method 33 myocardial time-activity curves were analyzed with different curve fitting methods: monoexponential, biexponential and monoexponential plus constant. A background correction was not applied. Biexponential curve fitting resulted in redundancy of parameters. Optimal curve fitting was obtained with monoexponential plus constant. The constant represents the background activity together with the stores radiolabelled lipids and the half-time value represents the wash-out of radioiodide from the myocardium. A strong relation was found between the constant and the half-time value: small errors in the determination of the constant (background activity) resulted in considerable errors of the half-time value. It is concluded that optimal analysis of a myocardial time-activity curve can be performed with a ...

1987-12-01

93

Access to Cardiac Interventional Services in Alabama and Mississippi: A Geographical Information System Analysis  

UK PubMed Central (United Kingdom)

ObjectiveThe objective of this study was to determine the contribution of distance to hospitals with cardiac interventional services (CIS) to county age-adjusted myocardial infarction...Full Text Available

94

Visualization of right atrial appendix by Thallium-201 myocardial scintigraphy: concise communication  

Energy Technology Data Exchange (ETDEWEB)

The atrial myocardium has been barely visible with thallium-201 myocardial scintigraphy. This is probably related to the difference in size, distance from anterior chest wall, and small coronary blood flow of the atrium, compared with the ventricle. We have encountered eight cases of visualization of the right atrial appendix (RAA). The RAA was identified from multiple projections in all cases and sometimes confirmed by radionuclide angiocardiography. Evidence derived from ECG, chest radiographs, and cardiac catheterization, indicated that the most important factor in the visualization might be the displacement of the RAA to a more anterior position.

1980-10-01

95

PET/CT cardiology: an area whose boundaries are still out of sight  

International Nuclear Information System (INIS)

Positron emission tomography (PET) and X-ray computed tomography (CT) performed with PET/CT cameras allow us to obtain concurrently information on the presence and degree of alterations of myocardial perfusion and metabolism and on coronary arteries calcification. Furthermore, by gated myocardial perfusion studies, PET may provide crucial information on regional coronary blood flow reserve and endothelial dysfunction. A number of recent papers provide some insight on the potential of PET/CT in cardiology and in the assessment of various cardiovascular diseases including various types of vasculitis and metabolic diseases.

2006-05-01

96

Hypersersensitivity and Kounis syndrome due to a viper bite  

British Library Electronic Table of Contents (United Kingdom)

A 60-year-old male was bitten by a venomous snake (Vipera ammodytes) and gradually developed signs of an allergic reaction including generalized itching, generalized rash, and chest discomfort. This was followed by severe retrosternal pain with electrocardiographic evidence of an inferior myocardial ischemia progressing to acute myocardial infarction. Cardiac enzymes and troponin, serum tryptase, and histamine were elevated. Coronary arteriography showed normal coronary arteries. This is a characteristic type I variant of Kounis syndrome, which is the concurrence of acute coronary syndromes with conditions associated with mast cell activation including allergic or hypersensitivity reactions as well as anaphylactic or anaphylactoid reactions. This is the first report to show that viper bite...

2006-01-01

97

Validity of the CT to attenuation coefficient map conversion methods  

International Nuclear Information System (INIS)

The most important commercialized methods of attenuation correction in SPECT are based on attenuation coefficient map from a transmission imaging method. The transmission imaging system can be the linear source of radioelement or a X-ray CT system. The image of transmission imaging system is not useful unless to replacement of the attenuation coefficient or CT number with the attenuation coefficient in SPECT energy. In this paper we essay to evaluate the validity and estimate the error of the most used method of this transformation. The final result shows that the methods which use a linear or multi-linear curve accept a error in their estimation. The value of mA is not important but the patient thickness is very important and it can introduce a error more than 10 percent in the final result.

2004-04-27

98

Radioiodinated phenoxyacetic acid derivatives as potential brain imaging agents, 2; Structure-biodistribution relationship  

Energy Technology Data Exchange (ETDEWEB)

In developing new brain imaging agents for single photon emission computed tomography (SPECT), we synthesized eleven radioiodinated phenoxyacetic acid derivatives and investigated the relationship between the chemical structure and in vivo characteristics. Biodistribution studies in mice revealed high initial brain uptake for all the compounds. Blood radioactivity level depended markedly upon the chemical stability of the compound. The alpha,alpha-dimethylester derivative, amide derivatives and diamine derivatives, which were stable to hydrolysis, showed low blood activity levels following intravenous administration. Disappearance of the ester and amide compounds from the brain was rapid. However, the diamine derivatives displayed improved retention in the brain. Compounds 3a and 4 possessed the best combination of high brain uptake and sufficient retention to be useful as potential brain imaging radiopharmaceuticals with SPECT devices.

1989-09-01

99

Quantitative 1-123 IMP SPECT, MR imaging, and neuropsychologic testing in AIDS dementia  

International Nuclear Information System (INIS)

The authors have performed I-123 IMP single- photon emission CT (SPECT) brain imaging on seven mildly demented patients with acquired immunodeficiency syndrome (AIDS) and on seven normal subjects. Pixel-intensity histograms have been analyzed for the fraction of pixels in the lowest quartile of the intensity range. This fraction (F) averaged 17.7% (standard deviation [SD] = 4.3) in the AIDS group and 12.6 (SD = 4.7) in the normal group (P <.05). Regression analysis of neuropsychological testing (NPT) scores vs F yielded a correlation coefficient of.71. The presence or degree of atrophy did not correlate with F or NPT scores.

100

Improved detection of myocardial infarction with technetium-99m stannous pyrophosphate and serum MB creatine phosphokinase  

International Nuclear Information System (INIS)

The relative sensitivity and combined value of myocardial technetium-99m stannous pyrophosphate imaging and determinations of serum MB creatine phosphokinase (the ''myocardial'' CPK isoenzyme) in detecting acute myocardial infarction were evaluated in 41 patients with suspected infarction and 23 patients recovering from cardiac surgery. In the patients with suspected infarction, myocardial infarction was confirmed in 25 and was consistently associated with increased serum MB CPK. Abnormal radionuclide images were obtained in 23 of 25 patients (92%)) with definite myocardial infarction and in 2 of 16 patients without confirmed infarction. Although the localization of infarction by imaging correlated well with the localization by electrocardiogram, infarct size estimated by imaging did not correlate well with estimates based on peak total serum CPK activity or serial changes in CPK ...

 
 
 
 
101

Single photon emission computed tomography and its neurological application  

Energy Technology Data Exchange (ETDEWEB)

A review is made of the various brain imaging agents utilised in the post few years with their own characters and respective advantages: cerebral blood volume tracers, non diffusible tracers, diffusible tracers among which gases and lipophilic agents. Our results with IAMP and SPECT are presented in two different clinical application fields: normal pressure hydrocephalus and cerebral ischemia.

1984-12-01

102

Single photon emission computed tomography and its neurological application  

International Nuclear Information System (INIS)

A review is made of the various brain imaging agents utilised in the post few years with their own characters and respective advantages: cerebral blood volume tracers, non diffusible tracers, diffusible tracers among which gases and lipophilic agents. Our results with IAMP and SPECT are presented in two different clinical application fields: normal pressure hydrocephalus and cerebral ischemia.

103

Scintigraphic imaging of dementia: Technical acquisition  

International Nuclear Information System (INIS)

Scintigraphic imaging of dementia relies today essentially on the study of brain Single Photo Emission Computed Tomography (SPECT) perfusion, after intravenous injection of 99mTc radio-pharmaceutic. This paper is based on the guidelines published in October 2001 by the European Association of Nuclear Medicine (http://eanm.org/). (author)

2007-06-01

104

Comparison of normal adult and children brain SPECT imaging using statistical parametric mapping(SPM)  

Energy Technology Data Exchange (ETDEWEB)

This study compared rCBF pattern in normal adult and normal children using statistical parametric mapping (SPM). The purpose of this study was to determine distribution pattern not seen visual analysis in both groups. Tc-99m ECD brain SPECT was performed in 12 normal adults (M:F=11:1, average age 35 year old) and 6 normal control children (M:F=4:2, 10.5{+-}3.1y) who visited psychiatry clinic to evaluate ADHD. Their brain SPECT revealed normal rCBF pattern in visual analysis and they were diagnosed clinically normal. Using SPM method, we compared normal adult group's SPECT images with those of 6 normal children subjects and measured the extent of the area with significant hypoperfusion and hyperperfusion (p<0.001, extent threshold=16). The areas of both angnlar gyrus, both postcentral gyrus, both superior frontal gyrus, and both superior parietal lobe showed significant hyperperfusion in normal adult group ...

2002-07-01

105

Boron in nuclear medicine: New synthetic approaches to PET and SPECT. Final report, May 1, 1986--April 30, 1996  

Energy Technology Data Exchange (ETDEWEB)

Research is described in the development of organometallic reagents in which the boron was attached to a nonreactive organic or inorganic matrix such as polystyrene, silica, or alumina. We developed the synthesis of oxygen-15 labelled butanol, which has been found to be a valuable blood flow agent in humans. We have also developed a series of polymeric borane derivatives which were used to prepare nitrogen-13 labelled amines.

1997-08-01

106

Assessment of detector sensitivity and uniformity during SPECT rotation  

International Nuclear Information System (INIS)

The purpose of this research was to: a) evaluate variations in sensitivity and uniformity of SPECT detectors during 360"0 rotation, b) explore the causes of the variations and c) to discuss a correction procedure. A flood source consisting of a lucite disc 47.7 cm in diameter containing 3 microcuries of Co-57 was constructed. This source can be firmly attached to the uncollimated detector guaranteeing no detector-source geometry change during rotation. Four different SPECT cameras were tested. Measurements were obtained at 45"0 intervals throughout a 360"0 rotation, and repeated in 3 different orientations with respect to the earth's magnetic field. In one camera the effects of the direction and strength of induced magnetic fields were studied. All detectors showed cyclic rotational variations in sensitivity; in three cameras 6%, in one 3%. The amplitude and phase of the sensitivity variation curves and the variations in uniformity were unique ...

1984-06-05

107

Amphetamines and pH-shift agents for brain imaging: Basic research and clinical results  

Energy Technology Data Exchange (ETDEWEB)

This book contains 18 selections. Some of the titles are: Labelling of amphetamines with /sup 123/I: Receptors for amphetamines; New amphetamine derivatives; Potential new approaches for the development of brain imaging agents for single-photon applications; and IM SPECT with the pinhole collimator.

1986-01-01

108

Amphetamines and pH-shift agents for brain imaging: Basic research and clinical results  

International Nuclear Information System (INIS)

This book contains 18 selections. Some of the titles are: Labelling of amphetamines with /sup 123/I: Receptors for amphetamines; New amphetamine derivatives; Potential new approaches for the development of brain imaging agents for single-photon applications; and IM SPECT with the pinhole collimator.

109

A high-sensitivity small animal SPECT system  

International Nuclear Information System (INIS)

Medical imaging using single gamma-ray-emitting radionuclides typically makes use of parallel hole collimators or pinholes in order to achieve good spatial resolution. However, a tradeoff in sensitivity is inherent in the use of a collimator, and modern preclinical single photon emission computed tomography (SPECT) systems detect a very small fraction of emitted gamma rays, often less than 0.1%. A system for small animal SPECT imaging which uses no collimators could potentially achieve very high sensitivity-several tens of percent-with reasonably sized detectors. This would allow two significant improvements in preclinical studies: images could be obtained more rapidly, allowing higher throughput for screening applications, or for dynamic processes to be observed with very good time resolution; and images could be obtained with less radioactive tracer, making possible the in vivo imaging of low-capacity receptor systems, aiding research into ...

2009-03-07

110

Integration of SPECT with CT to plan radiotherapy fields. n application to conformal irradiation for lung carcinoma; Integrazione delle immagini della Tomografia Computerizzata con emissione di fotone singolo in un sistema commerciale per l'elaborazione dei piani di radioterapia. Applicazione all'irradiazione conformazionale del carcinoma polmonare  

Energy Technology Data Exchange (ETDEWEB)

Single photon emission computed tomography (SPECT) of lung perfusions permits to map functioning lung parenchyma with higher sensitivity than CT. Delivering higher radiations doses it used to increase local control in lung carcinoma; this strategy is based on radiobiological and clinical studies. Lung parenchyma is a dose-limiting tissue in patients irradiated for lung cancer. Functional mapping based on SPECT and CT findings permits to design radiation beams such as to minimize irradiation of functioning lung. [Italian] L'integrazione delle immagini diagnostiche aventi diverso contenuto informativo anatomico-funzionale puo' essere utilizzata nella radioterapia per migliorare le procedure diagnostiche e ottimizzare la geometria dell'irraggiamento. I sistemi per l'elaborazione di piani di radioterapia oggi in uso sono direttamente interfacciati con gli apparecchi di Tomografia Computerizzata (TC) e ...

1999-04-01

111

Effects of ischemic-like insult on myocardial /sup 201/Tl accumulation  

Energy Technology Data Exchange (ETDEWEB)

Despite extensive clinical use of thallium-201 (/sup 201/Tl) for myocardial imaging, the effect of ischemia on myocardial accumulation and release of /sup 201/Tl independent of flow has not been fully defined. Therefore, myocardial accumulation of /sup 201/Tl in response to ischemic-like myocardial injury was assessed in vitro using the cultured fetal mouse heart preparation. Cultured fetal mouse hearts (n . 311) were subjected to injury simulating ischemia by deprivation of oxygen and oxidizable substrates for periods ranging from 15 minutes to 10 hours. The extent of irreversible injury was determined by the percentage of lactic dehydrogenase (LDH) lost from the hearts to the culture medium during recovery from injury. Injury was essentially reversible at 1 hour of insult. The fraction of /sup 201/Tl content in injured compared with control hearts was not significantly lower after 1 hour of insult. By ...

1983-04-01

112

Trace Elements in Human Myocardial Infarction Determined by Neutron Activation Analysis  

International Nuclear Information System (INIS)

By means of neutron activation analysis, injured and adjacent uninjured human heart tissue from 12 autopsy cases with myocardial infarction are investigated with respect to the concentration of 23 trace elements. The bulk elements K, Na and P are also determined. A recently developed ion-exchange technique, combined with subsequent y-spectrometry, is used. The following trace elements are determined: Ag, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mo, Rb, Sb, Sc, Se, Sm, Zn and W. In the injured tissue compared to the uninjured, calculation on a wet weight basis showed a decrease in Co, Cs, K, Mo, P, Rb and Zn, and an increase in Br, Ca, Ce, La, Na, Sb and Sm. The differences in Ca, La, Mo, P and Zn are dependent on the age of the myocardial infarction, and the regression lines for these elements are given. The concentration of the trace elements in uninjured tissue from infarcted hearts is compared to the concentration of these ...

1965-01-01

113

Regional myocardial perfusion in patients with atherosclerotic coronary artery disease, at rest and during angina pectoris induced by tachycardia  

International Nuclear Information System (INIS)

We studied regional myocardial perfusion by scintigraphic computer-assisted analysis of initial distribution, washout rates, and residual activity of "1"3"3Xe injected into the left coronary artery of four patients with normal arteriograms and 14 patients with coronary stenosis. At rest, residual activity in poststenotic regions was always greater than in control regions, but initial washout rates were not slower. During angina, following xenon injections, the amount of indicator distributed to the poststenotic regions was markedly reduced; the increase of the initial washout rates was smaller than in control regions relative to rest, and residual activity was higher. Initial washout rates did not differ as much as from those of normal myocardium because in severe ischemia too little indicator is deposited initially in these regions to produce a change of any magnitude. Indeed, when angina was induced immediately after the xenon injection, poststenotic washout ...

114

Transplantation of progenitor cells and regeneration enhancement in acute myocardial infarction (TOPCARE-AMI): final 5-year results suggest long-term safety and efficacy  

British Library Electronic Table of Contents (United Kingdom)

Background Limited data is available for investigating the long-term safety and effects of intracoronary progenitor cell therapy in patients with acute myocardial infarction (AMI). Objective To assess the clinical course, NT-proBNP and MRI data as objective markers of cardiac function of the TOPCARE-AMI patients at 5-year follow-up. Design The TOPCARE-AMI trial was the first randomized study investigating the effects of intracoronary infusion of circulating (CPC) or bone marrow-derived progenitor cells (BMC) in 59 patients with successfully reperfused AMI. Results Five-year follow-up data were completed in 55 patients, 3 patients were lost to follow-up. None of the patients showed any signs of intramyocardial calcification or tumors at 5?years. One patient died during the initial hospitali...

2011-01-01

115

Association Between Wasted Pressure Effort and Left Ventricular Hypertrophy in Hypertension: Influence of Arterial Wave Reflection  

British Library Electronic Table of Contents (United Kingdom)

BackgroundWave reflection during the systole increases left ventricular (LV) pressure, tension-time index (TTI) and myocardial oxygen requirement. The purpose of this study was to extract that component of extra myocardial oxygen requirement that is due to early systolic wave reflection, define it as wasted effort (?Ew), and examine its relationship to LV hypertrophy (LVH).MethodsRadial artery pressure waveforms were recorded using applanation tonometry and central aortic waveforms generated in 98 patients with untreated hypertension. Aortic augmentation index (AIa), wave reflection amplitude (i.e., aortic augmented pressure (AG)) and systolic duration (ED?Tr), ejection duration (ED) and round-trip travel time of the pressure wave (Tr) were calculated from the aortic waveform, a...

2008-01-01

116

Radioiodinated phenoxyacetic acid derivatives as potential brain imaging agents, 2  

International Nuclear Information System (INIS)

In developing new brain imaging agents for single photon emission computed tomography (SPECT), we synthesized eleven radioiodinated phenoxyacetic acid derivatives and investigated the relationship between the chemical structure and in vivo characteristics. Biodistribution studies in mice revealed high initial brain uptake for all the compounds. Blood radioactivity level depended markedly upon the chemical stability of the compound. The #alpha#,#alpha#-dimethylester derivative (1e), amide derivatives (2a-c) and diamine derivatives (3a, b, 4), which were stable to hydrolysis, showed low blood activity levels following i.v. administration. Disappearance of the ester and amide compounds from the brain was rapid. However, the diamine derivatives displayed improved retention in the brain. Compounds 3a and 4 possessed the best combination of high brain uptake and sufficient retention to be useful as potential brain imaging radiopharmaceuticals with ...

117

High-resolution brain SPECT imaging in attention deficit hyperactivity disorder children without comorbidity: quantitative analysis using statistical parametric mapping(SPM)  

Energy Technology Data Exchange (ETDEWEB)

We examined the abnormalities of regional cerebral blood flow(rCBF) in children with attention deficit hyperactivity disorder(ADHD) without comorbidity using statistical parametric mapping(SPM) method. We used the patients with not compatible to DSM-IV diagnostic criteria of ADHD and normal rCBF pattern in visual analysis as normal control children. Tc-99m ECD brain SPECT was performed on 75 patients (M:F=64:11, 10.0{+-}2.5y) with the DSM-IV diagnostic criteria of ADHD and 13 normal control children (M:F=9:4, 10.3{+-}4.1y). Using SPM method, we compared patient group's SPECT images with those of 13 control subjects and measured the extent of the area with significant hypoperfusion(p<0.01) in predefined 34 cerebral regions. Only on area of left temporal lobe showed significant hypoperfusion in ADHD patients without comorbidity (n=75) compared with control subjects(n=13). (n=75, p<0.01, extent threshold=16). rCBF of left ...

2002-07-01

118

Estimate of the scatter component in SPECT  

Energy Technology Data Exchange (ETDEWEB)

Analytical expressions that describe the dependence of slopes and amplitudes of the scatter distribution functions (SDF) on source depth and media density are used to estimate a scatter component in SPECT projection data. Since the ratio of detected scattered to total photons (S/T), SDF amplitude and slope depend strongly on line source length (SL) used to obtain SDFs, we compared estimated scattered components using SDFs, obtained for lengths of 2-21 cm. At 10 cm source depth, S/T changes from 0.19 to 0.36 when SL changes from 2 to 21 cm. Scatter amplitude`s dependence on source depth (d) in water was described by 6.38e{sup -0.186d} for a 2 cm and 16.15e{sup -0.129d} for a 21 cm SL. Slope was described by 0.292d{sup -0.601} for a cm SL and by 0.396d{sup -0.82} for a 21 cm SL. The estimated scatter components are compared with simulated SPECT projection data obtained with Monte Carlo modeling of six hot spheres placed in a cylindrical water ...

1996-12-31

119

Brain SPECT of chronic fatigue syndrome (CFS): SPM analysis of two age groups  

International Nuclear Information System (INIS)

Full text: Chronic fatigue syndrome (CFS) is a complex disorder characterised by profound fatigue and neuropsychiatric dysfunction. Previous studies with cerebral perfusion SPECT (rCBF) scans were performed with inhomogeneous patient populations and were not analysed with Statistical Parametric Mapping (SPM). We have used SPM to study subjects with moderate CFS based on the Fukuda criteria, who were not on medication and not depressed, compared to age matched control subjects. An apparent bimodal age distribution has been observed in CFS. Subjects were therefore divided into two age groups: 16-35 or under 35 (17 CFS, 11 control) and 36-61 or over 35 (15 CFS, 15 control). HMPAO brain SPECT was acquired on a 3-head camera. After lower window scatter subtraction, reconstruction with attenuation correction (mu=0.15/cm) and editing of facial activity, scans were spatially normalised (affine + 2x3x2 nonlinear) to SPM's anatomical space. SPM ...

2002-05-04

120

Assessment of left ventricular wall motion by optional multiple long-axial gated blood pool SPECT  

International Nuclear Information System (INIS)

Optional multiple long-axial gated blood pool SPECT images were prepared for the purpose of stereoscopic and quantitative imaging of left ventricular wall motion (LVWM). Sixteen patients with ischemic heart disease and 8 healthy subjects were imaged in 32 views in the 360 degrees position after iv injection of 740 MBq of Tc-99m-labeled human serum albumin D. The R-R interval was divided into 16. After preparing conventional oblique images, long-axial images were prepared. Shortening rate of left ventricular wall was calculated in 5 segments of the apex and base of the left ventricle. An average shortening rate in each segment was graded with a score from a minimum of 0 to a maximum of 40% or more. In the normal group, shortening rate in each segment, except for the base of the septal region, exceeded 40%. In the group of ischemic heart disease, radial shortening was capable of visualizing the degree and extent of the whole LVWM abnormality. LVWM abnormality seen on ...

1991-01-01

 
 
 
 
121

[Heart injuries: diagnosis and therapy].  

Science.gov (United States)

The clinical manifestation of wounds of the heart is determined by the mode, site and size of the injury as well as the structure of the pericardial and myocardial lesion. Diagnosis can be confirmed by ECG and echocardiography. Only 20% of the patients with penetrating wounds of the heart live for more than 30 minutes. Pericardio-centesis should be used only to gain time for a safe sternotomy, cardiac decompression and suture of the wound of the heart. An aggressive surgical approach is mandatory. Cardiopulmonary bypass is necessary only to correct of concomitant lesions. PMID:1983618

1990-01-01

122

Relation Between Myocardial Infarction Deaths and Solar Activity in Mexico  

Science.gov (United States)

We study the daily incidence of myocardial infarction deaths in Mexico for 4 years (1996-99) with a total of 129 917 cases in all the country, collected at the General Directorate of Epidemiology (National Ministry of Health). We divided the cases by sex and age and perform two kinds of analysis. First, we did an spectral analysis using the Maximum Entropy Method, considering the complete period, and minimum and maximum epochs of solar activity. The results show that the most persistent periodicity at higher frequencies in the myocardial infarction death occurrence is that of seven days. Considering the solar cycle phases, we found that during solar minimum times some frequencies are not detectable compared with solar maximum epochs, particularly that of seven days. Biological rhythms close to seven days, the circaseptans, are in general thought to be only the result of the social organization of life. However, this cannot be the only ...

2002-05-01

123

Pharmacokinetic parameters for thallium (I)-ions in man  

Energy Technology Data Exchange (ETDEWEB)

The pharmacokinetics of Tl/sup +/ were studied in 9 patients who underwent myocardial scintigraphy with /sup 201/Tl/sup +/. The time course of the /sup 201/Tl/sup +/ concentration fitted to an open two-compartment model. Using previously published dialysance values the influence of hemodialysis on Tl/sup +/ elimination was calculated. Hemodialysis in Tl/sup +/ intoxications should be moderately effective.

1983-05-01

124

Myeloid-Related Protein-8/14 and the Risk of Cardiovascular Death or Myocardial Infarction after an Acute Coronary Syndrome in the PROVE IT-TIMI 22 Trial  

UK PubMed Central (United Kingdom)

BackgroundUsing a transcriptional profiling approach, we recently identified myeloid-related protein-8/14 (MRP-8/14) to be expressed by platelets during acute MI....Full Text Available

2008-01-01

125

MRI in the diagnosis of non-compacted ventricular Myocardium (NCVM) compared to echocardiography  

International Nuclear Information System (INIS)

Purpose: To report the detection of con-compacted ventricular myocardium (NVCM) with MRI compared to echocardiography in 8 patients. Material and methods: Non-compaction of the ventricular myocardium is a congenital disorder characterized by an altered structure of the myocardial wall resulting from an intrauterine arrest in endomyocardial embryogenesis. The morphological findings consist of a prominent meshwork of multiple myocardial trabeculations and deep intertrabecular recesses, communicating with the left ventricular cavity. 8 consecutive patients (mean age 7.3 years) with clinical and echocardiographic signs of NCVM were examined by MRI (1.5 T, Vision, Siemens) in short axis and 2- and 4-chamber views, using T_1-weighted TSE and Cine-GRE in 6 patients and true FISP sequences in 2 patients. MRI and echocardiography were evaluated for visibility, signs of NCVM and involvement of myocardial wall segments. Thickness was ...

2003-09-01

126

Lyme myocarditis diagnosed by indium-111-antimyosin antibody scintigraphy  

Energy Technology Data Exchange (ETDEWEB)

We report a new case of Lyme disease with cardiac manifestations, which has been possible to follow during the long period of 12 years. We have detected the usual ECG abnormalities, and concentric hypertrophic myocardiopathy, by echocardiography. The acute myocarditis was demonstrated by /sup 111/In-antimyosin scintigraphy, which showed global myocardial uptake of the tracer, constituting the first report, to our knowledge, of Lyme myocarditis diagnosed by this method.

1989-06-01

127

Kappa-opioid receptor activation during reperfusion limits myocardial infarction via ERK1/2 activation in isolated rat hearts  

UK PubMed Central (United Kingdom)

BackgroundWe investigated whether p42/p44 extracellular signal-regulated kinases (ERK1/2) and/or phosphatidylinositol-3-OH kinase (PI3K)-Akt play a crucial role in cardioprotection...Full Text Available

2011-05-01

128

Usefulness of myocardial imaging by [sup 123]I-MIBG in assessment of diabetic neuropathy  

Energy Technology Data Exchange (ETDEWEB)

In diabetic patients with autonomic neuropathy, it is suggested that there is a reduced uptake of [sup 123]I-metaiodobenzylguanidine (MIBG) in the heart. We compared the difference of myocardial [sup 123]I-MIBG accumulation between 4 diabetic patients with triopathy and 6 patients without it. In all 10 patients, coronary angiography and [sup 201]Tl imaging (rest and 4 hours later) were performed. [sup 123]I-MIBG (111 MBq) was administered intravenously and its imaging was recorded on 15 minutes and 4 hours after injection. In all 4 cases with triopathy, [sup 123]I-MIBG imaging showed defect in apical and inferior region. In 2 out of 6 cases without triopathy, rapid clearance was noticed in apical and inferior region. There was no significant stenosis in right coronary artery and no defect in initial and delayed [sup 201]Tl images in all cases. We concluded that diabetic autonomic neuropathy in the heart was prominent in apical and inferior region and [sup ...

1993-10-01

129

Effects of carbon monoxide on myocardial ischemia  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study was to determine whether low doses of carbon monoxide (CO) exacerbate myocardial ischemia during a progressive exercise test. The effect of CO exposure was evaluated using the objective measure of time to development of electrocardiographic changes indicative of ischemia and the subjective measure of time to onset of angina. Sixty-three male subjects (41-75 years) with well-documented coronary artery disease, who had exertional angina pectoris and ischemic ST-segment changes in their electrocardiograms, were studied. Results from three randomized, double-blind test visits (room air, low and high CO) were compared. The effect of CO exposure was determined from the percent difference in the end points obtained on exercise tests performed before and after a 1-hr exposure to room air or CO. A significant dose-response relationship was found for the individual differences in the time to ST end point and angina for the pre-versus postexposure ...

1991-02-01

130

Determination of left ventricular ejection fraction and wall thickness in magnetic resonance imaging at 1.0 Tesla in comparison to echocardiography and biplanar ventriculography  

International Nuclear Information System (INIS)

We compared the values of the myocardial thickness and the left ventricle diameters measured with MRI and echocardiography. The ejection fraction was compared in MRI and ventriculography. 34 patients with different heart dysfunctions were examined with MRI (FISP 2D sequence). 26 of them were also studied by echocardiography and 20 by biplane cine-ventriculography. The enddiastolic thicknesses of the left ventricular postero-lateral wall and of the septum interventriculare were measured on short axis images. An ellipsoidal modell was used for volume calculation and ejection fraction. Correlation of MRI values of thickness and ejection fraction with echocardiographi and angiographi showed r>0,8. As known for 1.56 T Imagers, the myocardial thickness in MRI was underestimated compared to echocardiography (1.4 mm#+-#1.7). The ejection fraction was underevaluated compared to ventriculography (4.5%#+-#10.1). MRI (1.0 T) accurately measures ...

131

Changes in myocardial beta1-adrenergic receptor and stimulatory G-protein gene expression after chronic treatment with doxorubicin in rat.  

Science.gov (United States)

The gene expression of beta(1)-adrenergic receptor (beta(1)AR) and stimulatory G-protein Gsalpha in ventricle after chronic treatment with doxorubicin (DOX) in rat was investigated. The rats were treated with DOX in a dose of 2.5 mg/kg once a week for 5 weeks, the cumulative dose being 12.5 mg/kg. Two weeks after the last injection, the positive inotropic effect of isoproterenol was noticeably decreased in left atrial muscle preparations isolated from DOX-treated rats. Northern blot hybridization showed that the mRNA transcripts of beta(1)AR and Gsalpha, important signal transduction elements for regulating heart rate and contractility, were significantly decreased in the ventricle of DOX-treated rats. Thus, chronic treatment with DOX decreases the gene expression levels of myocardial beta(1)AR and Gsalpha. PMID:15353854

2004-08-01

132

Assessment of PET and MRI Polar Map using Gaussian Mixture Model  

International Nuclear Information System (INIS)

Cardiac disease research relies increasingly on small animal models and non-invasive imaging methods such as positron emission tomography (PET) and magnetic resonance imaging (MRI). Delayed enhancement magnetic resonance imaging (DE-MRI) using gadolinium-based contrast agents appear to be a visualizing infracted myocardium with high spatial resolution. Polar map (or bull's-eye image) was used to determination of the myocardial infarction area. Polar map is a comprehensive interpretation of the left ventricle. The infarct size was computed as the fraction of the total polar map areas. The threshold was computed as the percentage of mean intensity of the normal region. In other study, 50% predefined threshold value in varying range (30?70%) was most commonly use. However, predefined threshold value isn't acceptance in all case. The purpose of this study was to investigate methodological approach for automatic measurement of rat myocardial infarct ...

2010-10-01

133

Adenosine triphosphate loading thallium-201 myocardial scintigraphy. Optimal dose and diagnostic accuracy  

Energy Technology Data Exchange (ETDEWEB)

Adenosine triphosphate (ATP) is an alternative to dipyridamole or adenosine in thallium-201 myocardial scintigraphy. However, the optimal dose of ATP has not been determined. A Doppler guide wire study showed the coronary flow velocity at a dose of 0.15 mg/kg of ATP was equal or higher than that at 0.14 mg/kg of adenosine or 0.56 mg/kg of dipyridamole. ATP was given intravenously to 67 patients with coronary artery disease at 0.15 mg/kg/min for 6 min. Thallium-201 was injected at 3 min, followed by immediate and delayed (3 hrs) tomographic imaging. There was no serious side effect during examination, although chest pain (26%), dyspnea (17%), and flushing (33%) were common. The sensitivity and specificity to detect coronary artery disease were 98 and 100%, respectively. The sensitivity to detect left anterior descending artery, left circumflex artery, and right coronary artery lesions was 94, 59 and 77%, respectively. ATP loading thallium-201 scintigraphy provides ...

1995-01-01

134

Labelling of amphetamines with /sup 123/I  

International Nuclear Information System (INIS)

Within the past decade two important groups of radiopharmaceuticals labelled with /sup 123/I were introduced into the clinical application opening new areas of metabolic studies in nuclear medicine: radioiodinated fatty acids were developed for metabolic studies of the myocardium and radioiodinated amphetamine derivatives were prepared for studying brain diseases by means of SPECT. It must be emphasized that the radiochemical problems with both groups of compounds are practically the same since both are radioiodinated by a nucleophilic substitution mechanism using /sup 123/I directly in its anionic form. The clinical application of brain imaging agents, particularly the one of p-/sup 123/I-iodo-N-isopropylamphetamine, is important and will presumably increase as soon as the details of the individual biochemical steps, which are involved in brain uptake mechanisms, are evaluated. It is felt that the potential of the clinical IMP application is greater than the ...

135

A novel accelerated oxidative stability screening method for pharmaceutical solids  

British Library Electronic Table of Contents (United Kingdom)

Abstract Despite the fact that oxidation is the second most frequent degradation pathway for pharmaceuticals, means of evaluating the oxidative stability of pharmaceutical solids, especially effective stress testing, are still lacking. This paper describes a novel experimental method for peroxide-mediated oxidative stress testing on pharmaceutical solids. The method utilizes urea-hydrogen peroxide, a molecular complex that undergoes solid-state decomposition and releases hydrogen peroxide vapor at elevated temperatures (e.g., 30C), as a source of peroxide. The experimental setting for this method is simple, convenient, and can be operated routinely in most laboratories. The fundamental parameter of the system, that is, hydrogen peroxide vapor pressure, was determined using a modified spect...

2011-01-01

136

Natriuretic peptides in vascular physiology and pathology.  

Science.gov (United States)

Four major natriuretic peptides have been isolated: atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), C-type natriuretic peptide (CNP), and Dendroaspis-type natriuretic peptide (DNP). Natriuretic peptides play an important role in the regulation of cardiovascular homeostasis maintaining blood pressure and extracellular fluid volume. The classical endocrine effects of natriuretic peptides to modulate fluid and electrolyte balance and vascular smooth muscle tone are complemented by autocrine and paracrine actions that include regulation of coronary blood flow and, therefore, myocardial perfusion; modulation of proliferative responses during myocardial and vascular remodeling; and cytoprotective anti-ischemic effects. The actions of natriuretic peptides are mediated by the specific binding of these peptides to three cell surface receptors: type A natriuretic peptide receptor (NPR-A), type B natriuretic peptide receptor (NPR-B), ...

2008-01-01

137

Estimation of the parameter covariance matrix for aone-compartment cardiac perfusion model estimated from a dynamic sequencereconstructed using map iterative reconstruction algorithms  

Energy Technology Data Exchange (ETDEWEB)

In dynamic cardiac SPECT estimates of kinetic parameters ofa one-compartment perfusion model are usually obtained in a two stepprocess: 1) first a MAP iterative algorithm, which properly models thePoisson statistics and the physics of the data acquisition, reconstructsa sequence of dynamic reconstructions, 2) then kinetic parameters areestimated from time activity curves generated from the dynamicreconstructions. This paper provides a method for calculating thecovariance matrix of the kinetic parameters, which are determined usingweighted least squares fitting that incorporates the estimated varianceand covariance of the dynamic reconstructions. For each transaxial slicesets of sequential tomographic projections are reconstructed into asequence of transaxial reconstructions usingfor each reconstruction inthe time sequence an iterative MAP reconstruction to calculate themaximum a priori reconstructed estimate. Time-activity curves for a sumof activity in a blood ...

2004-01-01

138

Development of regional cerebral blood flow during childhood studied with Iodine-123-IMP SPECT  

International Nuclear Information System (INIS)

Regional cerebral blood flow (rCBF) was assessed with single photon emission computed tomography (SPECT), "1"2"3I-N-isopropyl-iodoamphetamine ("1"2"3I-IMP), and the Table-Look-Up method in 51 children (27 boys, 24 girls) considered neurologically normal and aged 1 month to 15 years (mean age, 4 years 1 month; standard deviation (SD) 3 years 11 months) divided into seven age groups. The rCBF was measured in cortical regions, the cerebellum, thalamus, and the head of the caudate nucleus. Curves for reference values and standard deviations were defined for each region. The rCBF rapidly increased until 2 years of age, reaching maximum values during the third to fifth periods (2 to 10 years of age) in each region. The rCBFs then decreased, reaching adult levels at 10 to 15 years of age. The rCBF reached maximum values later in the frontal region than in other regions. The rCBF during the early period increased most prominently in the occipital region. These results ...

2006-06-01

139

Comparison of /sup 99/Tcsup(m) complexes (NEP-DADT, ME-NEP-DADT and HMPAO) with /sup 123/IAMP for brain SPECT imaging in dogs  

Energy Technology Data Exchange (ETDEWEB)

In this study we have compared brain uptake and blood clearance of /sup 99/Tcsup(m)-N-ethylpiperi-dinediamino dithiol (/sup 99/Tcsup(m)-NEP DADT), its 4-methylated derivative (/sup 99/Tcsup(m)-Me-NEP-DADT) and /sup 99/Tcsup(m)-hexamethyl-propylene-amine-oxime (/sup 99/Tcsup(m)-HMPAO) with that of N-isopropyl(/sup 123/I)iodoamphetamine (/sup 123/IAMP) in two dogs. Single photon emission tomography (SPECT) was employed to measure brain accumulation and retention of the four radiopharmaceuticals. Cerebral uptake of the /sup 99/Tcsup(m) complexes was lower than that of /sup 123/IAMP. There was considerable extracerebral activity in the dog's head, especially in the olfactory and snout regions. Because of slow blood clearance, /sup 99/Tcsup(m)-HMPAO showed high uptake in these regions. Brain uptake of /sup 99/Tcsup(m)-HMPAO reached a plateau 5 to 10 min after intravenous injection and remained constant for the entire study period (1 h). /sup ...

1987-08-01

140

The role of insulin therapy and glucose normalisation in patients with acute coronary syndrome  

British Library Electronic Table of Contents (United Kingdom)

Patients with acute myocardial infarction (AMI) and diabetes mellitus, as well as patients admitted with elevated blood glucose without known diabetes, have impaired outcome. Therefore intensive glucose-lowering therapy with insulin (IGL) has been proposed in diabetic or hyperglycaemic patients and has been shown to improve survival and reduce incidence of adverse events. The current manuscript provides an overview of randomised controlled trials investigating the effect of IGL. Furthermore, systematic glucose?insulin?potassium infusion (GIK) has been studied to improve outcome after AMI. In spite of positive findings in some early studies, GIK did not show any beneficial effects in recent clinical trials and thus this concept has been abandoned. While IGL targeted to achieve normoglycaemi...

2011-01-01

 
 
 
 
141

Small heat shock protein 20 (HspB6) in cardiac hypertrophy and failure  

British Library Electronic Table of Contents (United Kingdom)

Hsp20, referred to as HspB6, is constitutively expressed in various tissues. Specifically, HspB6 is most highly expressed in different types of muscle including vascular, airway, colonic, bladder, and uterine smooth muscle; cardiac muscle; and skeletal muscle. It can be phosphorylated at Ser-16 by both cAMP- and cGMP-dependent protein kinases (PKA/PKG). Recently, Hsp20 and its phosphorylation have been implicated in multiple physiological and pathophysiological processes including smooth muscle relaxation, platelet aggregation, exercise training, myocardial infarction, atherosclerosis, insulin resistance and Alzheimer's disease. In the heart, key advances have been made in elucidating the significance of Hsp20 in contractile function and cardioprotection over the last decade. This mini-rev...

2011-01-01

142

Progress and problems in the chemistry of technetium-99m tracers  

International Nuclear Information System (INIS)

The recent acceleration of effort to elucidate and explore the coordination chemistry of technetium has been prompted mainly by the need for a new generation of radiotracers in nuclear medicine, preferentially for tomograhic studies. Current approaches and their limitations in designing "9"9"mTc complexes capable of penetrating cell membranes of the target organs, and remaining there sufficiently long, are reviewed. With the predominance of Tc(V) oxo compounds, especially for brain imaging agents, new N4 and N2S2 coordinate complexes have been developed by shifting from bidentate to tetradentate ligands with a variable side chain or other adjustable reactivity. The search for myocardial imaging agents has focused on a variety of mixed ligand complexes of Tc(III) and most promising [Tc(CNR)_6]"+ complexes of Tc(I). 64 refs. (author).

143

Myocardial pharmacokinetics of ebastine, a substrate for cytochrome P450 2J, in rat isolated heart  

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND AND PURPOSE It is well established that cytochrome P450 2J (CYP2J) enzymes are expressed preferentially in the heart, and that ebastine is a substrate for CYP2J, but it is not known whether ebastine is metabolized in myocardium. Therefore, we investigated its pharmacokinetics in the rat isolated perfused heart. EXPERIMENTAL APPROACH Rat isolated hearts were perfused in the recirculating mode with ebastine for 130-min. The concentrations of ebastine and its metabolites, hydroxyebastine and carebastine, were measured using liquid chromatography with a tandem mass spectrometry. The data were analysed by a compartmental model. The time course of negative inotropic response was linked to ebastine concentration to determine the concentration-effect relationship. KEY RESULTS Ebastine w...

2011-01-01

144

Clinical Evaluation of the Zilver Vascular Stent for Symptomatic Iliac Artery Disease  

British Library Electronic Table of Contents (United Kingdom)

PurposeTo evaluate the safety and effectiveness of the Zilver vascular stent in the treatment of de novo or restenotic lesions in the external and common iliac arteries.Materials and MethodsRegardless of the results of an initial percutaneous transluminal angioplasty (PTA), 151 consecutive patients were implanted with Zilver vascular stents (Cook, Bloomington, Ind) in up to two stenotic (?10 cm) or occluded (?5 cm) atherosclerotic lesions of the external or common iliac arteries. The primary endpoint was the rate of major adverse events within 9 months after the procedure. Major adverse events were defined as death, myocardial infarction, target lesion revascularization, and limb loss. Secondary endpoints included acute procedural success, 30-day clinical success, 9-month pat...

2008-01-01

145

Chronic sympathetic activation promotes downregulation of ?-adrenoceptor-mediated effects in the guinea pig heart independently of structural remodeling and systolic dysfunction  

British Library Electronic Table of Contents (United Kingdom)

It is uncertain if downregulation of ?-adrenoceptor signaling pathway is promoted by an enhanced adrenergic tone at an early stage of cardiac disease, or it develops secondary to detrimental local myocardial changes in advanced heart failure. We examined the integrity of ?-adrenoceptor signaling pathway upon chronic infusion of isoproterenol, a ?-adrenoceptor agonist, at a dose producing no structural left ventricular (LV) remodeling and systolic dysfunction. Subcutaneous isoproterenol infusion (400??g?kg?1?h?1 over 16?days) to guinea pigs using osmotic minipumps produced no change in cardiac weights, LV internal dimensions, myocyte cross-sectional area, extent of interstitial fibrosis, and basal contractile function. Isolated, perfused heart preparations from isoproterenol-treated guinea ...

2011-01-01

146

Chronic inflammation and mortality in haemodialysis: effect of different renal replacement therapies. Results from the RISCAVID study  

British Library Electronic Table of Contents (United Kingdom)

Background. The `RISchio CArdiovascolare nei pazienti afferenti all' Area Vasta In Dialisi (RISCAVID) study is an observational and prospective trial including the whole chronic haemodialysis (HD) population in the northwest part of Tuscany (1.235 million people). The aim of the study was to elucidate the relevance of traditional and non-traditional risk factors of mortality and morbidity in HD patients as well as the impact of different HD modalities.Methods. A total of 757 HD patients (mean age 66 +- 14 years, mean dialytic age 70 +- 76 months, diabetes 19%) were prospectively followed up for 30 months and all-cause mortality, cardiovascular (CV) mortality and non-fatal CV events (acute myocardial infarction and stroke) were registered. At the time of the enrolment, demographic, clinical...

2008-01-01

147

Aspirin Use Is Associated With an Improved Long-Term Survival in an Unselected Population Presenting With Unstable Angina  

British Library Electronic Table of Contents (United Kingdom)

AbstractBackground Few published data are available on the benefits of aspirin use in patients with unstable angina (UA). Hypothesis Aspirin use carries a mortality benefit in a population-based cohort of patients presenting with UA. Methods All residents of Olmsted County, Minnesota presenting to local emergency departments with acute chest pain from January 1985 through December 1992 having symptoms consistent with UA were identified through medical records. A total of 1628 patients were identified with UA and were stratified by aspirin use in-hospital and at discharge. Cardiovascular mortality and nonfatal myocardial infarction and stroke were assessed over a median of 7.5 years follow-up and all-cause mortality data over a median of 16.7 years. The mean age of patients with UA was 65 y...

2010-01-01

148

As time goes by? The fallacy of thrombolysis in STEMI networks  

British Library Electronic Table of Contents (United Kingdom)

Primary percutaneous coronary intervention (PPCI) is superior to thrombolysis (TL) as reperfusion therapy in ST-elevation myocardial infarction (STEMI). TL is a rapidly available, but semi-effective therapy (effective reperfusion in 50% of patients only), whereas PPCI is a potentially delayed, but highly effective therapy (effective reperfusion in >90%). Since TL loses its efficacy beyond 2?3?h after symptom onset, it is a significant reperfusion alternative to PPCI in early presenters only. The individual decision to treat an early presenter with PPCI or TL requires the evaluation of the time delay between potential start of TL or PPCI, the PCI-related delay (PRD). PRD is greatest, if TL is given in the prehospital setting. Until now, prehospital TL as the most rapidly available reperfusi...

2011-01-01

149

Arterial and venous thrombosis in patients with von Willebrand?s disease: A critical review of the literature  

British Library Electronic Table of Contents (United Kingdom)

All patients with von Willebrand?s disease (vWD) who showed an arterial or venous thrombosis and were reported in the literature have been evaluated. 11 patients had arterial thrombosis while 19 had venous thrombosis for a total of 30 cases. 9 out the 11 cases with arterial thrombosis had myocardial infarction. Two had cerebral thrombosis. Associated risk factors for arterial thrombosis were available only for three patients who showed, respectively, smoking and dyslipidemia (2 cases) and smoking and intravenous desmopressin infusion (1 case). The majority of patients with venous thrombosis showed DVT with or without PE. Four patients presented with apparently isolated PE. In two instances thrombosis occurred in unusual sites (central retinal vein and portal vein, respectively). Several as...

2006-01-01

150

The development of sigma-receptor specific radiopharmaceuticals for spect imaging of human tumors  

International Nuclear Information System (INIS)

The authors have been involved for the last few years in developing high affinity sigma-receptor-specific radiopharmaceuticals for use in nuclear medicine. They recently demonstrated that sigma-1 receptors are expressed in human melanoma cells and that sigma receptors could be used as external markers for non-invasive imaging. In order to determine the presence of sigma receptors in other human tumors they have screened numerous non-small cell lung carcinoma, melanoma and breast cancer cell lines. All of these cell lines expressed high sigma receptor densities using commercially available ["3H]-(+)-pentazocine or ["3H]DTG tritiated sigma ligands. Therefore, a sigma ligand with high affinity in both sigma-1 and sigma-2 subtype pharmacological assays could be potentially useful for imaging a variety of primary and metastatic sites of various origins. The authors describe recent efforts to develop high affinity sigma radiopharmaceuticals and pharmacological studies to support the binding ...

1994-08-21

151

The chemistry of technetium(V) complexes containing tetradentate amine oxime ligands  

International Nuclear Information System (INIS)

Technetium-99m was previously shown to form a stable, neutral and lipopholic complex with propylene amine oxime, PnAO. This Tc-99m-PnAO complex was shown to efficiently extracted by normal brain. However, it is not sufficiently retained in the brain to image its cerebral distribution using convertional SPECT (single-photon emission computerized tomography) instrumentation. A number of derivatives of PnAO have been synthesized and their technetium-99m complexes have been biologically evaluated. A number of these have been shown to have high brain uptake without exhibiting the rapid cerebral clearance that was observed with Tc-99m-PnAO. To better understand the chemistry of these potential brain imaging agents, a number of technetium-99 complexes of derivatives of PnAO have been synthesized and characterized. Substituents on the tetradentate amine oxime backbone were varied to probe the effect(s) of these structural changes on the properties of the resultant Tc(V) ...

152

New Tc-99m brain imaging agents  

Energy Technology Data Exchange (ETDEWEB)

In developing new Tc-99m brain perfusion imaging agents for SPECT, a series of BAT (bis-aminoethanethiol) derivatives was prepared. These N/sub 2/S/sub 2/ ligands formed stable and neutral complexes with reduced Tc-99m, either by Sn(II)-PPi or sodium borohydride reduction. The purity of the Tc-99m complexes was >95% (HPLC reverse-phase column, acetonitrile: pH 7.0 buffer, 85:15). The biodistribution in rats was evaluated using I-125 iodoantipyrine (IAP), a free diffusible tracer, as the internal reference. Compounds with a free hydroxyl group (I and IV) showed lower brain uptake, inspite of high P.C.; this may be related to in vivo instability of the complexes. High initial brain uptake was observed for three compounds (II, III and V), however, only compound V (P.C.=384) showed significant brain retention. Planar imaging with compound V in a monkey demonstrated that the compound localized in brain and the retention time was T/sub 1/2/=35 min. Compounds of this ...

1984-01-01

153

New Tc-99m brain imaging agents  

International Nuclear Information System (INIS)

In developing new Tc-99m brain perfusion imaging agents for SPECT, a series of BAT (bis-aminoethanethiol) derivatives was prepared. These N/sub 2/S/sub 2/ ligands formed stable and neutral complexes with reduced Tc-99m, either by Sn(II)-PPi or sodium borohydride reduction. The purity of the Tc-99m complexes was >95% (HPLC reverse-phase column, acetonitrile: pH 7.0 buffer, 85:15). The biodistribution in rats was evaluated using I-125 iodoantipyrine (IAP), a free diffusible tracer, as the internal reference. Compounds with a free hydroxyl group (I and IV) showed lower brain uptake, inspite of high P.C.; this may be related to in vivo instability of the complexes. High initial brain uptake was observed for three compounds (II, III and V), however, only compound V (P.C.=384) showed significant brain retention. Planar imaging with compound V in a monkey demonstrated that the compound localized in brain and the retention time was T/sub 1/2/=35 min. Compounds of this ...

1984-06-05

154

Hepatobiliary scintigraphy in current pediatric practice  

Energy Technology Data Exchange (ETDEWEB)

Hepatobiliary scintigraphy is the only non-invasive technique providing real-time assessment of hepatocytes function and bile progression from the liver to the intestine; for this reason it is of great importance in the study of jaundice and many other disorders of the liver and the biliary tract in children. Ultrasonography is the initial method of evaluating the intra- and extrahepatic bile ducts dilatation: the differential diagnosis between biliary atresia and neonatal hepatitis cannot however be done without hepatobiliary scintigraphy. Cystic fibrosis patients also require hepatobiliary scintigraphy; liver and biliary tract disease can really occur independently of the underlying disease severity and the presence of steatorrhoea. Hepatobiliary imaging in children who have undergone liver transplantation is of major importance; it can assess vascularity, parenchymal function biliary drainage, possible presence of a bile leak and obstruction; it has very good sensitivity and ...

1998-06-01

155

Development of gamma-emitting, receptor binding radiotracers for imaging the brain and pancreas  

Energy Technology Data Exchange (ETDEWEB)

This progress report covers period from Nov. 1, 1989 to Aug. 31, 1990. The long term objective was to develop receptor-binding radiotracers for SPECT or PET imaging of CNS or peripheral nervous system. The specific chemistry aims, as understood on the basis of past findings, were: to synthesize and develop a more polar analogs of 4IQNB, possessing similar binding characteristics but eliminated more rapidly from the surrounding tissues and the target organ, to design a method of introducing a technetium chelating group onto a molecule or cholinergic agent without drastic lowering of its apparent affinity, to synthesize and develop radiotracers based on m-AChR antagonists selective for one of the subtypes of the receptor. The chemistry service aims were to prepare and characterize (R,R)- and (R,S)-4IQNB and derivatives, to provide the triazene intermediate to other investigators, and to provide ({sup 123}I)4IQNB for in vivo imaging. The biochemistry aims were to ...

1990-01-01

156

Application of low-resolution Raman spectroscopy for the analysis of oxidized olive oil  

British Library Electronic Table of Contents (United Kingdom)

The aim of this study was to evaluate the potential of low-resolution Raman spectroscopy for monitoring the oxidation status of olive oil. Primary and secondary oxidation parameters such as peroxide value, K"2"3"2 and K"2"7"0 were studied. Low-resolution Raman spectra ranging from 200 to 2700 cm^-^1 in a set of 126 oxidized and virgin olive oil samples were collected directly using a probe. Partial Least Squares was used to calibrate the Raman instrument for the different targeted parameters. The performance of the models was determined by using validation sets, and the best results obtained were: R^2 = 0.91, RMSEP = 2.57 for the peroxide value content; R^2 = 0.88, RMSEP = 0.37 for K"2"3"2; and R^2 = 0.90, RMSEP = 0.08 for K"2"7"0. These results demonstrated that low-resolution Raman spect...

2011-01-01

157

Analysis of the quantitative structure activity relationship of technetium-99m-labeled diaminedithiol (DADT) and propyleneamineoxime (PAO) brain blood flow analogues  

Energy Technology Data Exchange (ETDEWEB)

In the search for new brain imaging agents for use with single photon emission computed tomography (SPECT), quantitative structure activity relationship (QSAR) analysis of the correlations between initial brain uptake and physicochemical parameters like lipophilicity, log P, molecular weight, log MW and log U/D (undissociated/dissociated), of the {sup 99m}Tc-DADT (diaminedithiol) complexes and {sup 99m}Tc-PAO (propyleneaminoxime) complexes have been analyzed. High correlations are found for both the {sup 99m}Tc-DADT complexes (r = 0.94) and for the {sup 99m}Tc-PAO complexes (r = 0.83) which are significant at 99.9 and 99.5 percentile level, respectively. These results will help the further design of better ligands for {sup 99m}Tc in brain imaging. (author).

1991-01-01

158

Swimming exercise training prior to acute myocardial infarction attenuates left ventricular remodeling and improves left ventricular function in rats.  

Science.gov (United States)

The effect of exercise training prior to acute myocardial infarction (AMI) on left ventricular (LV) remodeling is poorly understood. This study investigated the protective effect of 3 weeks of swimming exercise training prior to AMI on cardiac morphology and function. Male Sprague-Dawley rats (n = 35) were randomly assigned to 3 groups: swimming training (n = 14, 90 min, 5 days/wk, 3 wk), sedentary (n =14), and controls (n = 7, no exercise, no MI). At the end of the training/sedentary period, rats were subjected to AMI (ExMI and SedMI) induced by surgical ligation of the left coronary artery. Thereafter, the rats remained sedentary for a 4-wk recovery period. Trans-thoracic echocardiography was performed in each group at the end of the exercise/sedentary period (pre-AMI), 24 hr after AMI, and following recovery (4 wk after AMI). No differences were observed in LV dimensions and function pre-AMI among the 3 groups; however, LV-end systolic diameter (LVESD) and ...

2005-01-01

159

Nuclear medicine progress report for quarter ending March 31, 1985  

Energy Technology Data Exchange (ETDEWEB)

Radioiodinated 15-(p-iodophenyl)-3,3-dimethylpentadecanoic acid (DMIPP) has been prepared as a new terminal iodophenyl-substituted fatty acid containing dimethyl-branching at the beta-position. Iodine-125-labeled DMIPP showed rapid, high myocardial uptake (min, mean % injected dose/g) in fasted rats (5, 4.67; 30, 5.06; 60, 4.79; 120, 4.37), and also exhibited high heart:blood ratios (min, ratio) 5, 3:1; 30, 12:1; 60, 12:1; 120, 13:1. These data demonstrate an unanticipated much longer myocardial residence time with DMIPP (+/sub 1/2/ 7-8 h) than observed with either the 3-monomethyl (BMIPP) analogue (+/sub 1/2/ 30-45 min) or the rapidly metabolized straight-chain (IPP) analogue (+/sub 1/2/ 10-15 min). The (/sup 123/I)DMIPP is thus an excellent candidate for clinical evaluation of regional fatty acid metabolism under conditions where the uptake of energy substrates can be assessed independent of regional blood delivery. Studies with the new ...

1985-07-01

160

[Natriuretic peptides--relevance in intensive care].  

Science.gov (United States)

The family of natriuretic peptides consists of the atria natriuretic peptide (ANP), the cerebral natriuretic peptide (BNP), the type C natriuretic peptide (CNP) and the peptide isolated from the dendroaspis snakes' poison (DNP), whose presence in humans has not been confirmed. The physiological function of ANP is in the control of arterial blood pressure by regulation of systemic vascular resistance of blood vessels. BNP is produced as one of the factors in the acute response to inflammatory tissue damage, mainly in coronary vessels. Increased serum concentrations of natriuretic peptides have been found in stress situations, such as trauma or major surgery, systemic hypotension, and in intrinsic myocardial dysfunction. High concentrations of natriuretic peptides were observed in severe sepsis, septic shock and in multiple organ failure, probably due to increased secretion by mediators of the inflammatory process.The highest concentrations of ANP and BNP were found ...

 
 
 
 
161

Routine upfront abciximab versus standard periprocedural therapy in patients undergoing primary percutaneous coronary intervention for cardiogenic shock: The PRAGUE-7 Study. An open randomized multicentre study  

British Library Electronic Table of Contents (United Kingdom)

Background: The outcome of acute myocardial infarction (AMI) complicated with cardiogenic shock is poor. The aim of this study was to analyse, whether upfront abciximab administration could improve the outcomes of cardiogenic shock. Methods: This multicentre open trial randomized 80 patients with AMI complicated by cardiogenic shock expected to undergo primary PCI into group A (routine upfront-pre-procedural-abciximab bolus followed by 12-h abciximab infusion) and group B (standard therapy). The study primary objective was 30-day combined outcome (death/reinfarction/stroke/new severe renal failure). Results: PCI was technically successful in 90% (A) versus 87.5% (B) patients. Abciximab was used in 100% (A) versus 35% (B). The primary endpoint occurred in 17 group A patients (42.5%) and 11 ...

2011-01-01

162

Natriuretic peptides in the pathophysiology of congestive heart failure.  

Science.gov (United States)

A hallmark of congestive heart failure (CHF) is the activation of the cardiac endocrine system, in particular atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP). The natriuretic peptides are a group of structurally similar but genetically distinct peptides that have diverse actions in cardiovascular, renal, and endocrine homeostasis. ANP and BNP are of myocardial cell origin and C-type natriuretic peptide (CNP) is of endothelial origin. ANP and BNP bind to the natriuretic peptide-A receptor (NPR-A), which, via 3',5'-cyclic guanosine monophosphate (cGMP), mediates natriuresis, vasodilatation, renin inhibition, antimitogenesis, and lusitropic properties. CNP lacks natriuretic actions but possesses vasodilating and growth inhibiting actions via the guanylyl cyclase-linked natriuretic peptide-B receptor. All three peptides are cleared by the natriuretic peptide-C receptor and degraded by the ectoenzyme neutral endopeptidase 24.11, both of which are ...

2000-05-01

163

MRI in the diagnosis of non-compacted ventricular Myocardium (NCVM) compared to echocardiography; MR-Tomographie in der morphologischen Darstellung der isolierten non-compaction des linksventrikulaeren Myokards (NCVM)  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To report the detection of con-compacted ventricular myocardium (NVCM) with MRI compared to echocardiography in 8 patients. Material and methods: Non-compaction of the ventricular myocardium is a congenital disorder characterized by an altered structure of the myocardial wall resulting from an intrauterine arrest in endomyocardial embryogenesis. The morphological findings consist of a prominent meshwork of multiple myocardial trabeculations and deep intertrabecular recesses, communicating with the left ventricular cavity. 8 consecutive patients (mean age 7.3 years) with clinical and echocardiographic signs of NCVM were examined by MRI (1.5 T, Vision, Siemens) in short axis and 2- and 4-chamber views, using T{sub 1}-weighted TSE and Cine-GRE in 6 patients and true FISP sequences in 2 patients. MRI and echocardiography were evaluated for visibility, signs of NCVM and involvement of myocardial wall segments. Thickness ...

2003-09-01

164

Animal and human studies of a new /sup 99m/Tc labelled phosphine-isocyanide complex with possible applications to radionuclide ventriculography  

Energy Technology Data Exchange (ETDEWEB)

A new /sup 99m/Tc-phosphine-isocyanide complex with the general structure (/sup 99m/Tc (DEPE)/sub 2/(CNR)/sub 2/)/sup +/ has been synthesised and tested in animals and one human. In three animal species (rat, rabbit, dog), the complex is an efficient myocardial imaging agent, while in humans it remains in the blood pool. The complex is 100% protein bound in animals and humans, but whereas in humans it is attached to a 51.5 kdalton protein (probably prealbumin), in rabbits it appears to be bound to a larger macromolecule (M.W.>100 kdalton). The efficiency of the complex for blood pool labelling was tested in a human volunteer and compared with the standard in vivo red cell labelling technique with stannous pyrophosphate. A satisfactory radionuclide angiogram could be performed with less than 370 MBq of the complex. The count rate for the complex (cps/MBq) was 15% higher than that obtained with the labelled red cells and the absence of splenic activity was ...

1987-04-01

165

Synthesis and characterization of ["1"2"5I]-N-(N-benzylpiperidin-4-YL)-4-iodobenz amide, a potential high affinity sigma ligand for imaging breast cancer  

International Nuclear Information System (INIS)

Three regio-isomers of N-(N-benzylpiperidin-4-yl)-4-iodobenzamide, IBP, were prepared and evaluated for their sigma affinities. All three isomers (2, 3, and 4-substituted) showed high affinities for sigma-1 receptors in guinea pig brain membranes (Ki - 1.64 nM, 3.02 nM, 1.70 nM respectively) against ["3H]-(+)-pentazocine, a sigma-1 selective ligand. 2-IBP and 4-IBP showed modest affinities for sigma-2 sites in rat liver (Ki = 29.6 nM. 25.2 nM respectively) against ["3H]DTG in the presence of dextrallorphan to mask sigma-1 sites. The homologous competition binding studies of 4-["1"2"5I]BP in MCF-7 human breast tumor cells showed high affinity dose-dependent binding. Competition binding studies with haloperidol and DTG also showed a high affinity binding (Ki = 4.6 nM, 60 nM respectively), demonstrating the sigma specificity. The saturation binding (Scatchard analysis) of ["3H]DTG with MCF-7 cell membrane preparations gave Kd of 24.54 nM and a Bmax of 2071 fmol/mg protein. These results ...

1994-08-21

166

Synthesis and PET imaging of the benzodiazepine receptor tracer [N-methyl-"1"1C]iomazenil  

International Nuclear Information System (INIS)

The central benzodiazepine receptor tracer [N-methyl-"1"1C]iomazenil (Ro 16-0154) was synthesized by alkylation of the desmethyl precursor noriomazenil with ["1"1C]methyl iodide. The ["1"1C]CH_3I (prepared by reduction of ["1"1C]CO_2 with LiAlH_4 followed by reaction with HI) was reacted with noriomazenil inN,N -dimethylformamide and Bu_4N"+OH"- for 1 min at 80 deg. C and purified by HPLC (C_1_8, 34% CH_3CN/H_2O, 7 mL/min). The product was obtained with synthesis time 35 #+-# 5 min (mean #+-# SD, n = 7), radiochemical yield (EOB) 36 #+-# 16%, radiochemical purity 99 #+-# 1%, and specific activity 5100 #+-# 2800 mCi/#mu#mol. Absorbed radiation doses were calculated from previously acquired human biodistribution data. The urinary bladder wall received the highest dose (0.099 mGy/MBq) for 4.8 h voiding interval and the effective dose equivalent was 0.015 mSv/MBq. After i.v. injection of ["1"1C]iomazenil in an adult baboon or healthy human volunteer, radioactivity accumulated in the cortex ...

1995-07-01

167

Status of lead and bismuth for radioimmunoimaging and radioimmunotherapy  

International Nuclear Information System (INIS)

Tumor-targeted monoclonal antibodies (mAb) might be useful as diagnostic or therapeutic agents when linked to cytotoxic or imaging reagents. Our group is working to test this hypothesis by linking cytocidal and image-producing isotopes to mAb and testing the utility of the radioimmunoconjugates formed in animal model systems. Radioiodines were first employed for these purposes,but unfavorable nuclear properties (half-lives, #gamma#-ray and #beta#-particle energies) and chemical reactivity (deiodination in vivo) limit their utility. Labeling immunoproteins with metallic radionuclides offers more versatility in that the selection of potentially useful radiometals spans the periodic table.Of the metallic radionuclides with physical properties most suited for use with mAb in nuclear medicine, few are more available or desirable than those of bismuth ("2"1"2Bi) and lead ("2"0"3Pb, "2"1"2Pb), as listed in Table 1. "2"1"2Bi or "2"1"2Pb could serve as sources for highly cytocidal ...

1990-08-26

168

Nuclear Medicine Program progress report for quarter ending September 30, 1992  

Energy Technology Data Exchange (ETDEWEB)

The radioiodination and in vivo evaluation of p-iodocaramiphen a muscarinic antagonist which binds with high affinity to the M[sub 1] receptor subtype in vitro are described. Biodistribution studies in female Fischer rats demonstrated that [[sup 125]I]-piodocaraminphen had significant cerebral localization, but the uptake did not demonstrate specific uptake in those cerebral regions rich in muscarinic receptors, and radioactivity washed out rapidly from the brain. In addition there was no significant blockage of activity when the rats were preinjected with quinuclidinyl benzilate. These results suggest that p-iodocaramiphen is not a good candidate for the in vivo study of M[sub 1] muscarinic receptor populations by SPECT. Because of the widespread interest and expected importance of the availability of large amounts of tungsten-188 required for the tungsten-188/rhenium-188 generator systems, we have investigated the large-scale production of tungsten-188 in the ...

1992-12-01

169

Dosimetric evaluation and therapeutic response to iodine-131 labelled lipiodol in treatment of hepatocellular carcinomas; Evaluation dosimetrique et reponse therapeutique de la curietherapie metabolique des hepatocarcinomes par le lipiodol marque par l'iode 131  

Energy Technology Data Exchange (ETDEWEB)

Faced with increasing indications for the use of iodine-131 labelled lipiodol in the treatment of hepatocellular carcinoma (HCC), it appears essential to develop an individualized dosimetrY so we can predict the potential effectiveness of this treatment and adjust the activity to be injected. We developed a dosimetric protocol based on imagery and dedicated to calculation of the tumoral dose during the treatment of hepatocellular carcinoma by iodine-131 labelled lipiodol. This concept was developed on a SPECT- CT gantry, and integrates corrections for the phenomena of attenuation, diffusion and dead time. The dose is calculated according to the formalism proposed by the Medical Internal Radiation Dose Committee (MIRD). This protocol was applied to a series of 41 patients in the framework of a retrospective study. The results obtained in terms of biodistribution are compatible with previously published data. The total biological response rate is 42% (n= 41) for the ...

2006-12-15

170

A stable neurotensin-based radiopharmaceutical for targeted imaging and therapy of neurotensin receptor-positive tumours  

International Nuclear Information System (INIS)

Neurotensin (NT) and its high affinity receptor (NTR1) are involved in several neoplastic processes. Thus, NT-based radiopharmaceuticals are potential tracers for targeted diagnosis and therapy of NTR-positive tumours. A new analogue based on NT(8-13), NT-XIX, with the three enzymatic cleavage sites stabilised, was synthesised and tested. The synthesis was performed by Boc strategy. Labelling with "9"9"mTc/"1"8"8Re was performed using the tricarbonyl technique. Metabolic stability was tested in vitro and in vivo. NT-XIX was further characterised in vitro in HT-29 cells and in vivo in nude mice with HT-29 xenografts. NT-XIX showed much longer half-lives than non-stabilised analogues. Binding to NTR1 was highly specific, although the affinity was lower than that of natural NT. Bound activity rapidly internalised into HT-29 cells and 50% remained trapped after 24 h. In the time-course biodistribution, the highest uptake was found in the tumour at all p.i. times. In vivo uptake was ...

2009-01-01

171

Immunoscintigraphy with anti-225.28S for ocular melanoma - a comparison with histology and immunohistochemistry  

Energy Technology Data Exchange (ETDEWEB)

Aim: The purpose of this prospective study was to evaluate the value of immunoscintigraphy (ISG) with anti-225.28S in clinically suspected ocular melanoma. Methods: For this purpose standardized ISG was performed in 36 patients using both planar acquisition and emission computed tomography (ECT). Ocular melanoma was present in 31 patients. In 21 patients therapy was enucleation of the eye. These specimens were evaluated by histology and immunohistochemistry in 11 of 21 patients. Results: Regarding the clinical diagnosis, ISG was positive only in 15 of 31 patients with ocular melanoma, regarding histology in 11 of 21 and regarding immunohistochemistry in 5 of 6 patients with a positive immunoreaction. 5 patients showed no immunoreactivity, their ISG was negative. Conclusion: Thus a good correlation between ISG and immunohistochemistry was observed. However ISG using the cutaneous melanoma antibody 225.28S cannot be recommended for the diagnostic work-up of an ocular melanoma considering ...

1997-03-01

172

Developments of PET radioligands for NMDA receptors  

International Nuclear Information System (INIS)

Aim: There has been a great demand for developments of the radioligands to visualize the N-methyl-D-aspartate (NMDA) receptors by PET/SPECT. We have recently synthesized two C-11 labeled antagonists for the glycine-binding site on NMDA receptors. The aim of this work is to examine for their in vitro and in vivo binding characteristics, and to evaluate their potentials as PET radioligands for the NMDA receptors. Materials and methods: Two C-11 labeled 4-hydroxy-2-quinolones (1 and 2) were synthesized by conventional methylation of the corresponding phenols with ["1"1C]methyl iodide. In vitro and ex vivo quantitative autoradiographs with imaging plate, as well as animal PET, were employed in order to evaluate their in vitro and in vivo binding to the NMDA receptors. Results: The compound 1 showed the specific binding to rat brain slices with higher localization in the hippocampus and cerebral cortex than in the cerebellum. Both glycine antagonists and agonists ...

2002-09-01

173

[New cardiotonic agents].  

Science.gov (United States)

The possibilities for therapy in the field of severe cardiac insufficiency have been extended in recent years by the introduction of novel agents endowed with a positive inotropic action. These substances may be arranged in two large classes: sympathomimetic agents and "non sympathomimetic--non digitalis-like" inotropic agents. The stimulant action of noradrenaline, adrenaline and isoproterenol on beta-adrenergic myocardial receptors has been clearly demonstrated but the usefulness of these medicines is limited by their positive chronotropic and arrhythmogenic actions. Dopamine and dobutamine have proved to be very useful in the treatment of patients in intensive care units. However, the exclusively intravenous route of administration limits their importance to the medium or long term. Several compounds, which are active by the oral route, have been the subject of therapeutic trials for the short or medium term. The problems posed by their use result, in the first ...

1985-12-01

174

The influence of melatonin on metabolic changes in female rats induced by continuous irradiation and/or administration of 7,12-dimethylbenz/a/anthracene  

International Nuclear Information System (INIS)

Metabolic profile is an important biological marker of neoplastic processes not only in the tumor itself but also in the host organism. The neuro-hormone melatonin has been implicated in the experiments as an oncostatic agent. Female Wistar:Han SPF rats (Velaz, Prague, Czech Republic) were irradiated continuously for 15 days using a daily gamma rays dose of 96 mGy. At the end of exposure one group of rats was administered 5 mg/kg b.w. of dimethylbenz/a/anthracene (DMBA) intragastrically. During the period of exposure to ionizing radiation a part of the animals was supplied with melatonin (M) at a concentration of 20 #mu#l/ml in drinking water. Selected parameters of lipid and carbohydrate metabolism and levels of selected hormones were determined 2, 30 and 100 days post-irradiation. The irradiation itself caused only small changes in tissue lipids. The application of a single low dose (subthreshold from the point of view of induction of mammary tumors) of DMBA caused more pronounced ...

175

Radiolabelled D2 agonists as prolactinoma imaging agents  

Energy Technology Data Exchange (ETDEWEB)

During the past year, further studies on mAChR were conducted. These studies included verification of the difference in pituitary distribution based on ligand charge. The pituitary localization of TRB. A neutral mAChR ligand, was verified. The lack of QNB blockade of TRB uptake was tested by blockage with scopolamine, another mAChR antagonist and by testing the effect in a different strain of rat. Neither scopolamine or change of rat strain had any effect. We concluded that TRB uptake in pituitary is not a receptor-mediated process. Further studies were conducted with an additional quaternized mAChR ligand: MQNB. Pituitary localization of MQNB, like MTRB, could be blocked by pretreatment with QNB. We have tentatively concluded that permanent charge on a mAChR antagonist changes the mechanism of uptake in the pituitary. Time course studies and the effects of DES on myocardial uptake are reported. A brief report on preliminary results of evaluation of quaternized ...

1989-08-01

176

Pathogenesis of trypanosome infections in cattle  

International Nuclear Information System (INIS)

The potential application of radioisotopes are not discussed in this review of trypanosome pathogenesis in cattle. Initially, structural changes in the lymphoid system are characterized by marked proliferation and germinal centre formation, whereas in long-standing infections the lymphoid organs become depleted. These changes appear associated with immunodepression. Anaemia dominates the clinical disease syndrome in bovine trypanosomiasis. It develops with the onset of parasitaemia and is largely haemolytic, resulting from increased red blood cell destruction by phagocytosis. Several factors may be involved in this process including haemolysins produced by the trypanosome, immunological mechanisms, fever, disseminated intravascular coagulation and an expanded and active mononuclear phagocytic system. During this phase of the disease, cattle respond well to chemotherapy. However, in later phases of the disease, when trypanosomes cannot be detected, the anaemia sometimes persists and ...

1979-05-11

177

Kinetics of in vivo binding of antagonist to muscarinic cholinergic receptor in the human heart studied by Positron Emission Tomography  

Energy Technology Data Exchange (ETDEWEB)

Positron Emission Tomography (PET) was used to analyze in vivo antagonist binding to human myocardial muscarinic cholinergic receptor. The methiodide salt of the muscarinic antagonist, quinuclidinyl benzilate (MQNB), was labeled with the positron emitter, Carbon-11, and injected intravenously to 8 normal subjects. /sup 11/C-MQNB concentration was determined in vivo in the ventricular septum from 40 cross-sectional images acquired at the same transverse level over a period of 70 minutes. In 4 subjects, various amounts of unlabeled atropine were rapidly injected at 20 minutes to study whether atropine competitively inhibited MQNB. The kinetics of binding of /sup 11/C-MQNB were not the same in vivo and in vitro. The apparent dissociation rate of /sup 11/C-MQNB in vivo was much slower (by 1 to 2 orders of magnitude) than that observed in vitro with /sup 3/H-QNB. After atropine injection, /sup 11/C-MQNB dissociated from its binding sites at a rate that apparently ...

1984-08-27

178

Effects of exogenous norepinephrine on the spatial distribution of cardiac MIBG accumulation. Comparison with myocardial blood flow  

International Nuclear Information System (INIS)

Male rats were injected intravenously for 15 min with physiological saline (as control) (0.05 #mu#g/kg/min) or norepinephrine (NE) (0.1 #mu#g/kg/min) followed by 740 kBq of MIBG. Rats were injected for more 30 min (early stage group) and for more 4 hr (late stage group) with physiological saline or NE. Five MBq of "9"9"mTc-tetrofosmin (TF) was administered instead of MIBG in another group. The heart was isolated and uptake of MIBG or TF of right ventricle, apex, and left ventricle (divided into 8 parts) was measured. In control group, MIBG uptake of apex was significantly lower than that of lateral wall in both early and late groups. In NE group, MIBG uptake showed a tendency to decrease in both early and late groups. Compared with control group, the uptake of anterior wall in late group decreased significantly at NE 0.1 #mu#/kg/min. The TF uptake in control group was not different in each part. In NE group, the TF uptake of right ventricle decreased significantly compared with that of ...

1998-06-01

179

Effects of chronic swimming training on cardiac sarcolemmal function and composition.  

Science.gov (United States)

Cardiac contractile function is dependent on the integrity and function of the sarcolemmal membrane. Swimming exercise training is known to increase cardiac contractile performance. The purpose of the present study was to examine whether a swimming exercise program would alter sarcolemmal enzyme activity, ion flux, and composition in rat hearts. After approximately 11 wk of exercise training, cardiac myosin and actomyosin Ca2+-adenosinetriphosphatase (ATPase) activity was significantly higher in exercised rat hearts than in sedentary control rat hearts. Glycogen content was increased in plantaris and gastrocnemius muscles from exercised animals as was succinic dehydrogenase activity in gastrocnemius muscle of exercised rats in comparison to sedentary rat preparations. Sarcolemmal vesicles were isolated from hearts of exercise-trained and control rats. Sarcolemmal Na+-K+-ATPase and K+-p-nitrophenylphosphatase activities, Na+-Ca2+ exchange, and passive Ca2+ binding did not differ between ...

1989-04-01

180

Characterization of tris(N-substituted-2-methyl-3-hydroxy-4-pyridinonato)technetium(IV) cations  

Energy Technology Data Exchange (ETDEWEB)

A burgeoning interest in technetium coordination chemistry has been spurred by its widespread use in nuclear medicine. Recent focus has been on the design and preparation of new technetium complexes, the lipophilicity, polarity, and overall charge of which can be readily altered by simple substitutions in the molecular framework of the ligand in order to optimize the biodistribution and target specific organs. Examples are cationic (Cardiolite) and neutral (Ceretec) technetium complexes, used as myocardial and brain imaging agents, respectively. The authors have been pursuing a continuing study of tris(3-hydroxy-4-pyridinonato)gallium and -indium complexes that are water soluble, are hydrolytically stable, and are of varying lipophilicity and neutral charge. Studies of in vivo in rabbits and mice have revealed that several of these cationic complexes may be useful as morphologic kidney imaging agents, with [{sup 99m}Tc(pap){sub 3}]{sup +} showing elevated levels in ...

1994-11-23

 
 
 
 
181

Characterization of tris(N-substituted-2-methyl-3-hydroxy-4-pyridinonato)technetium(IV) cations  

International Nuclear Information System (INIS)

A burgeoning interest in technetium coordination chemistry has been spurred by its widespread use in nuclear medicine. Recent focus has been on the design and preparation of new technetium complexes, the lipophilicity, polarity, and overall charge of which can be readily altered by simple substitutions in the molecular framework of the ligand in order to optimize the biodistribution and target specific organs. Examples are cationic (Cardiolite) and neutral (Ceretec) technetium complexes, used as myocardial and brain imaging agents, respectively. The authors have been pursuing a continuing study of tris(3-hydroxy-4-pyridinonato)gallium and -indium complexes that are water soluble, are hydrolytically stable, and are of varying lipophilicity and neutral charge. Studies of in vivo in rabbits and mice have revealed that several of these cationic complexes may be useful as morphologic kidney imaging agents, with ["9"9"mTc(pap)_3]"+ showing elevated levels in the kidneys ...

182

Incidence of lesions as described by MRI in focal epilepsy of frontal and temporal onset; Inzidenz kernspintomographisch erfassbarer Laesionen bei der Abklaerung fokaler Epilepsien frontalen und temporalen Ursprunges  

Energy Technology Data Exchange (ETDEWEB)

Aim: Today, MRI is an integral part of the presurgical evaluation of patients suffering from partial epilepsy. These patients frequently show focal morphological abnormalities with potential epileptogenic character and surgical resection of these lesions is associated with superior postsurgical outcome as to seizure frequency. Apart from easily detectable defects, such as post-traumatic lesions or cerebral infarction, as wide variety of mainly small abnormalities can be detected using MRI. Methods: In this study, 484 patients suffering from partial epilepsy of temporal or frontal onset were evaluated for the incidence of different lesions in this population. Results: All lesions found were included without evaluating their potential epileptogenicity, which remains to be proven using other procedures (EEG, SPECT, PET, etc.). Involvement of the hippocampal formation was a major finding in temporal lobe epilepsy, which could be detected as sclerosis (T2w-images), ...

1997-09-01