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Sample records for dos radionuclideos 201tl

  1. High spin spectroscopy of 201Tl

    NASA Astrophysics Data System (ADS)

    Das Gupta, S.; Bhattacharyya, S.; Pai, H.; Mukherjee, G.; Bhattacharya, Soumik; Palit, R.; Shrivastava, A.; Chatterjee, A.; Chanda, S.; Nanal, V.; Pandit, S. K.; Saha, S.; Sethi, J.; Thakur, S.

    2013-10-01

    The high spin structure of 201Tl has been studied by γ-ray spectroscopic method using the 198Pt(7Li,4n)201Tl reaction at 45 MeV beam energy. The level scheme of 201Tl has been considerably extended through the observation of 31 new transitions. Several new band structures have been established. The 9/2- oblate band has been significantly extended beyond the particle alignment frequencies. The band structures and the other excited states have been compared with the neighboring odd-A Tl isotopes and with the even-even core nucleus 200Hg. The total Routhian surface calculations have been performed to study the deformation and shape changes as a function of spin in this nucleus.

  2. Photon emission probabilities of 201Tl

    NASA Astrophysics Data System (ADS)

    Kawada, Y.; Hino, Y.; Gatot, W.

    1990-01-01

    Precise measurements of the gamma- and X-ray emission probabilities per decay of 201Tl have been performed using a photon spectrometer with a reverse electrode Ge coaxial detector (LO-AX). The source activity was determined by the 4πβ-γ coincidence technique, and the influence of the coincidence sum effects between the K X-rays and the gamma rays was assessed. Radioactive impurities such as 200Tl and 202Tl were also taken into account.

  3. Giant dipole resonance in 201Tl at low temperature

    NASA Astrophysics Data System (ADS)

    Dang, N. Dinh; Hung, N. Quang

    2012-10-01

    The thermal pairing gap obtained by embedding the exact solutions of the pairing problem into the canonical ensemble is employed to calculate the width and strength function of the giant dipole resonance (GDR) within the phonon damping model. The results of calculations describe reasonably well the data for the GDR width as well as the GDR linearized strength function, recently obtained for 201Tl in the temperature region between 0.8 and 1.2 MeV, for which other approaches that neglect the effect of nonvanishing thermal pairing fail to describe.

  4. Effect of time and exercise on the clearance rate of (201)Tl in normal and ischemic myocardium.

    PubMed

    Backus, Barbra E; Hezemans, Rachel E L; Verburg, Frederik A; Keijsersa, Ruth G M; Konijnenberg, Mark W; Verzijlbergen, J Fred

    2010-06-01

    Simultaneous dual isotope (SDI) acquisition of (201)Tl rest/(99m)Tc-sestamibi stress-myocardial perfusion single photon emission computed tomography is a desirable new procedure in nuclear cardiology. In this protocol (201)Tl is injected at rest but imaging is performed not earlier than after exercise. Therefore, one must be convinced that throughout exercise (201)Tl remains distributed in an identical pattern as at rest. Before SDI can be applied clinically, (201)Tl rest MPS before and after exercise test needs to be compared for equality. The aim of this study was to assess the effect of time and exercise on the clearance of preinjected (201)Tl in normal and ischemic myocardium. In 122 patients rest (201)Tl and delayed (n =20) or poststress (n= 102) (201)Tl imaging was performed. Quantitative analysis of mean counts-per-pixel was performed for each segment in a 17-segment model. Differences between rest and delayed or poststress (201)Tl MPS were calculated. Patients with a poststress (201)Tl image were divided into normal (N= 66) and ischemic (N= 36) groups. Visual analysis was performed by two independent observers scoring the 17 segments on a scale of 0-4. The overall difference between rest (201)Tl and poststress (201)Tl MPS was - 15.4%. Normal and ischemic patients showed 16.2 and 14.0% (P =0.17) washout, respectively. Visual assessment by two independent observers revealed no regional differences between rest (201)Tl and delayed or poststress (201)Tl MPS. (201)Tl poststress MPS shows significant washout of thallium. This washout is not segmental, but global over the myocardium. No significant differences are found between normal and ischemic myocardium. The poststress (201)Tl MPS is a reliable reflection of rest perfusion. SDI acquisition of (201)Tl rest/(99m)Tc-sestamibi stress-MPS is clinically applicable.

  5. Dipyridamole 201Tl scintigraphy in the evaluation of prognosis after myocardial infarction

    SciTech Connect

    Okada, R.D.; Glover, D.K.; Leppo, J.A. )

    1991-09-01

    Dipyridamole 201Tl imaging has been proposed as an alternative to exercise ECG testing for the prehospital discharge evaluation of patients recovering from myocardial infarction. The rationale is that many postinfarction patients with exercise-induced ischemia experience later cardiac events, and the sensitivity of predischarge exercise ECG testing in patients with multivessel disease ranges from only 45% to 62%. In addition, several groups of investigators have shown the sensitivity of submaximum exercise 201Tl imaging to be less than ideal. This report summarizes the current status of dipyridamole 201Tl imaging in the period of 1-13 days after myocardial infarction. Although the number of studies performed to date is limited, the following conclusions can be drawn: dipyridamole 201Tl imaging after myocardial infarction was associated with no serious side effects, and those present could be quickly reversed with aminophylline; redistribution with dipyridamole 201Tl images definitely correlates with prognosis after uncomplicated myocardial infarction; dipyridamole 201Tl imaging is definitely useful in patients unable to exercise for a variety of reasons; and future studies are definitely indicated to further define the role of dipyridamole 201Tl imaging for assessing prognosis, especially in those patients undergoing interventional therapy after acute myocardial infarction.

  6. Spontaneous changes in /sup 201/Tl myocardial perfusion imaging after myocardial infarction

    SciTech Connect

    Buda, A.J.; Dubbin, J.D.; MacDonald, I.L.; Strauss, H.D.; Orr, S.A.; Meindok, H.

    1982-12-01

    To examine regional myocardial perfusion after myocardial infarction, 26 patients underwent exercise electrocardiographic testing with /sup 201/Tl myocardial perfusion imaging 3 weeks and 3 months after infarction. At 3 weeks, 9 of 26 patients (35%) had myocardial ischemia by exercise electrocardiographic testing, whereas 18 of 26 (69%) had ischemia by /sup 201/Tl imaging. The /sup 201/Tl scintigrams were scored by dividing each image, in 3 views, into 5 segments, using a 5-point scoring scheme. The exercise /sup 201/Tl score was 44.3 +/- 1.2 and increased to 47.3 +/- 1.2 in the redistribution study (p less than 0.001). Three months after infarction, although there was a significantly greater rate-pressure product which would predict a larger ischemic defect and a decrease in the stress /sup 201/Tl score, the stress score was improved (48.3 +/- 1.1, p less than 0.001). The redistribution score was similar, that is, 48.9 +/- 1.0. The improvement in /sup 201/Tl myocardial perfusion was associated with a loss of stress-induced ischemia in 8 patients (30%). These results indicate that spontaneous improvements in /sup 201/Tl myocardial perfusion imaging may occur after myocardial infarction.

  7. Cold pressor /sup 201/Tl myocardial scintigraphy in the diagnosis of coronary artery disease

    SciTech Connect

    Ahmad, M.; Dubiel, J.P.; Haibach, H.

    1982-12-01

    /sup 201/Tl myocardial scintigraphy was performed during cold pressor stimulation in 36 patients aged 36 to 69 years. Thirty-one patients had coronary artery disease and 5 patients did not, as confirmed by coronary cineangiography. /sup 201/Tl (1.5 to 2 mCi) was injected at 30 seconds of the cold pressor stimulation. The product of systolic pressure X heart rate increased from a baseline of 77.4 +/- 16 (standard deviation (SD)) to 103.6 +/- 17 at 30 seconds of the cold pressor test (p less than 0.0005). Transient perfusion deficits developed in 24 of 31 patients with coronary artery disease (sensitivity 77%), and all 5 patients without coronary artery disease had normal scintigrams. The sensitivity in detecting coronary artery disease was 40% in patients with 1 vessel disease, 91% in patients with 2 vessel disease, and 100% in patients with 3 vessel disease. Exercise electrocardiograms (available in 29 of 36 patients) were positive for ischemia in 18 of 24 patients with coronary artery disease and in 1 of 5 patients without coronary artery disease (sensitivity 75% and specificity less than 80%). Exercise /sup 201/Tl scintigrams, obtained in 16 patients, were positive in 11 patients with coronary artery disease and positive cold pressor /sup 201/Tl scintigrams. Five patients without coronary artery disease and with normal cold pressor /sup 201/Tl scintigrams had normal exercise /sup 201/Tl scintigrams. Coronary cineangiography performed during cold pressor stimulation in 6 patients who had positive cold pressor and exercise /sup 201/Tl scintigrams did not show coronary spasm. Our data indicate that cold pressor thallium-201 scintigraphy offers promise as a noninvasive test in the diagnosis of coronary artery disease and may be used in patients in whom exercise testing is not feasible.

  8. Visual and semi-quantitative assessment of brain tumors using (201)Tl-SPECT.

    PubMed

    Nose, Ayumi; Otsuka, Hideki; Nose, Hayato; Otomi, Yoichi; Terazawa, Kaori; Harada, Masafumi

    2013-01-01

    To evaluate the usefulness of (201)Tl-SPECT in differentiating benign from malignant brain tumors. Eighty-eight patients (44 males and 44 females) with 58 high-grade (WHO grade III-IV) and 30 low-grade (WHO grade I-II) tumors were evaluated with (201)Tl-SPECT. (1) Visual assessment was performed by board-certificated radiologists using (201)Tl-SPECT. Tumors were classified in two groups (Tl-positive and Tl-negative) and scored using the five grade evaluation system. Receiver operating characteristic (ROC) analysis was performed in the Tl-positive group. (2) Semi-quantitative assessment involved measurement of early and delayed (201)Tl uptake, and the retention index (RI) was applied as follows: RI=delayed uptake ratio/early uptake ratio. Three combinations of RI using mean and maximum values of the region of interest were calculated. (1) Seventy-four Tl-positive and 14 Tl-negative tumors. The area under the ROC curve (AUC) estimated by three radiologists exceeded a value of 0.7. The value was greater when estimated by the more experienced radiologist. (2) In all RIs, the difference of RI between high-grade tumors and low-grade tumors was statistically significant. A visual and semi-quantitative assessment using (201)Tl-SPECT was found to be useful for differentiating benign from malignant brain tumors.

  9. Value of planar 201Tl imaging in risk stratification of patients recovering from acute myocardial infarction

    SciTech Connect

    Gibson, R.S.; Watson, D.D. )

    1991-09-01

    Although exercise ECG testing has been shown to have important prognostic value after acute myocardial infarction, exercise 201Tl scintigraphy offers several potential advantages, including: (1) increased sensitivity for detecting residual myocardial ischemia; (2) the ability to localize ischemia to a specific area or areas subtended by a specific coronary artery; (3) the ability to identify exercise-induced left ventricular dysfunction, which is manifested by increased lung uptake or transient left ventricular dilation; and (4) more reliable risk stratification of individual patients. The more optimal prognostic efficiency of 201Tl scintigraphy partially results from the fact that the error rate in falsely classifying patients as low risk is significantly smaller with 201Tl scintigraphy than with stress ECG. Because of these substantial advantages, there seems to be adequate rationale for recommending exercise perfusion imaging rather than exercise ECG alone as the preferred method for evaluating mortality and morbidity risks after acute myocardial infarction.

  10. /sup 201/Tl perfusion study of ''ischemic'' ulcers of the leg: prognostic ability compared with Doppler ultrasound

    SciTech Connect

    Siegel, M.E.; Stewart, C.A.; Kwong, P.; Sakimura, I.

    1982-04-01

    Thallium 201 perfusion analysis was compared with Doppler ultrasound as a means of determining the healing potential of an ischemic ulcer of the leg in 27 patients. The degree of hyperemia was determined by comparative point counting of the /sup 201/Tl distribution in and about the ulcer. Using established Doppler criteria and a hyperemia ratio greater than 1.5:1, ultrasound alone correctly predicted healing in 15 out of 23 cases and /sup 201/Tl in 20 out of 23. Ultrasound correctly predicted non-healing in 3 out of 6 cases, compared with 5 out of 6 for /sup 201/Tl. The positive predictive value of the /sup 201/Tl study was 63%, versus 27% for ultrasound, and the negative predictive value was 95% for /sup 201/Tl and 83% for ultrasound. The accuracy of /sup 201/Tl and ultrasound was 86% and 62%, respectively. This limited study suggests that /sup 201/Tl perfusion scanning is a useful noninvasive test of ulcer healing potential and may be more sensitive than Doppler ultrasound.

  11. /sup 201/Tl scintigraphy after surgical repair of hemodynamically significant primary coronary artery anomalies

    SciTech Connect

    Rajfer, S.I.; Oetgen, W.J.; Weeks, K.D. Jr.; Kaminski, R.J.; Rocchini, A.P.

    1982-06-01

    Nine patients with hemodynamically significant congenital coronary artery anomalies underwent surgical repair at our institution during the period 1960 to 1979. Four received diagnoses of anomalous left coronary artery arising from the pulmonary artery, while five patients had coronary artery fistulae. Stress /sup 201/Tl scintigraphy was performed on these patients 0.5 to 18 years after surgical correction as a means of assessing the adequacy of myocardial perfusion. No perfusion defects were visualized on any of the thallium studies. The surgical procedure used did not appear to influence the results of /sup 201/Tl stress imaging. Thus, these nine patients with surgically corrected primary coronary artery anomalies had no evidence of ischemia as assessed by stress thallium scintigraphy. Serial preoperative and postoperative thallium studies are now indicated to determine the role of this procedure in the management of hemodynamically significant congenital coronary artery anomalies.

  12. 201Tl+-labelled Prussian blue nanoparticles as contrast agents for SPECT scintigraphy

    NASA Astrophysics Data System (ADS)

    Perrier, M.; Busson, M.; Massasso, G.; Long, J.; Boudousq, V.; Pouget, J.-P.; Peyrottes, S.; Perigaud, Ch.; Porredon-Guarch, C.; de Lapuente, J.; Borras, M.; Larionova, J.; Guari, Y.

    2014-10-01

    Prussian blue (PB) and its analogues on the nanometric scale are exciting nano-objects that combine the advantages of molecular-based materials and nanochemistry. Herein, we demonstrate that ultra-small PB nanoparticles of 2-3 nm can be easily labelled with radioactive 201Tl+ to obtain new nanoprobes as radiotracers for 201-thallium-based imaging.Prussian blue (PB) and its analogues on the nanometric scale are exciting nano-objects that combine the advantages of molecular-based materials and nanochemistry. Herein, we demonstrate that ultra-small PB nanoparticles of 2-3 nm can be easily labelled with radioactive 201Tl+ to obtain new nanoprobes as radiotracers for 201-thallium-based imaging. Electronic supplementary information (ESI) available: Experimental details and procedures, toxicological data, PXRD, TEM images, kinetics and adsorption isotherms, SPECT/CT images, Tl+ captation profiles. See DOI: 10.1039/c4nr03044c

  13. Abnormal 201Tl myocardial single photon emission computed tomography in energetic male patients with myocardial bridge.

    PubMed

    Huang, W S; Chang, H D; Yang, S P; Tsao, T P; Cheng, C Y; Cherng, S C

    2002-11-01

    Myocardial bridge is a relatively benign condition where a major coronary artery is bridged by a band of muscle and narrows during systole, particularly during rapid heart rates. Its clinical presentation and electrocardiogram (ECG) changes overlap with that of coronary artery disease. 201Tl myocardial perfusion imaging is thus frequently prescribed for further evaluation. This retrospective study was carried out to determine the 201Tl image patterns in patients with myocardial bridge. A total of 17 male patients (aged from 30 to 63 years) who had a positive exercise ECG and angiographic evidence of myocardial bridge in the mid-third of the left anterior descending coronary artery were recruited. Most of them were robust and received routine physical check-ups. They had no known heart disease or medication that affected cardiac function. The patients' clinical presentations, echocardiograph and exercise ECG findings were analysed. 201Tl single photon emission computed tomography (SPECT) was performed by intravenous injection of 201Tl (111 MBq) immediately following stress (treadmill or dipyridamole induced) and 4 h after stress, using a fixed, right angle camera equipped with a low energy, general purpose collimator. The images were interpreted independently by two experienced nuclear medicine physicians. Nine of the 17 patients had anterior chest pain during exercise. All patients had an abnormal ECG during exercise, including ST-T wave depression in leads II, III and aVF, and v4-6. Except for eight patients revealing reversible perfusion defect (R), 16 of the 17 patients also exhibited a partial reversible perfusion defect (PR) or a significant reverse redistribution (RR) scan pattern in the anterior or inferior walls of the left ventricle. Myocardial bridge should be taken into consideration in energetic male patients who had abnormal exercise ECGs and the corresponding patterns of Tl SPECT abnormalities including R, PR and RR.

  14. Differential renal uptake of 201Tl: requirements for acquisition, display and quantification.

    PubMed

    Hurwitz, G A; Powe, J E; Mattar, A G; Reid, R H; Driedger, A A; Rendak, I; Hogendoorn, P

    1991-10-01

    Renal uptake of 201Tl may have a role in screening for renal asymmetry in hypertensive patients (HP) who are referred for myocardial scintigraphy. The qualitative aspects of digitized planar images, and quantified differential renal uptake (DRU) of 201Tl were rated by comparing a simple technique (S) for outlining each kidney with an interpolative background subtracted technique (IB). These parameters were assessed in an initial series of patients by varying the length of acquisition (from 1 to 5 min), delay in acquisition (from 10 to 210 min after injection), and image preparation (nine-point smoothing). Six blinded observers rated the quality of coded images. Image quality was improved (P less than 0.01) by increasing the length of acquisition to at least 2 min, by smoothing of the images and by imaging within 2 h of 201Tl injection. Variability in quantification of DRU was suboptimal with acquisition for only 1 min and was more adversely affected with S than with IB. Clinical application of the quantitative technique was assessed in 180 HP and 32 normotensive controls. With IB, the normal range for DRU was slightly greater than for S. The two techniques were comparable in identifying abnormal cases and found 21 +/- 3% (S) and 19 +/- 3% (IB) of HP as lying outside the normal 99% confidence interval. Both quantitative techniques showed excellent agreement with renal angiography (n = 24). Furthermore, preliminary experience with surface markers and with 180 degrees tomography suggests the potential for simultaneous correction for renal depth. These data justify the use of adjunctive renal imaging during myocardial scintigraphy with 201Tl.

  15. Thrombolysis in acute myocardial infarction using intracoronary streptokinase: assessment by /sup 201/Tl scintigraphy

    SciTech Connect

    Schuler, G.; Schwarz, F.; Hofmann, M.; Mehmel, H.; Manthey, J.; Maeurer, W.; Rauch, B.; Herrmann, H.J.; Kuebler, W.

    1982-09-01

    Twenty-one patients with acute myocardial infarction, admitted to the hospital within 4 hours after the onset of symptoms, were studied by seven-pinhole /sup 201/Tl scintigraphy before and 1 hour and 24 hours after intracoronary fibrinolysis using streptokinase. The size of the /sup 201/Tl perfusion defect was assessed from myocardial cross sections reconstructed from the original seven-pinhole data and expressed as a fraction of left ventricular circumference. Recanalization was achieved in 16 patients within 3.9 +/- 1.6 hours after onset of symptoms (group A). In these patients, the size of the perfusion defect had decreased from 36 +/- 17% to 19% +/- 15% (p less than 0.001) at 24 hours. No significant change was detected by redistribution at 1 hour after the intervention. In five patients, intracoronary fibrinolysis was unsuccessful, and the vessel remained occluded (group B). The /sup 201/Tl perfusion defect affected 40 +/- 15% of the left ventricular circumference before the intervention; it remained virtually unchanged at 1 hour (37 +/- 16%) and at 24 hours (41 +/- 15%) after fibrinolysis. The perfusion defect was most reduced in patients with extensive collaterals supplying the ischemic area or with subtotal occlusion of the affected coronary artery. We conclude that successful intracoronary fibrinolysis may reduce the size of the /sup 201/Tl perfusion defect in many patients with acute myocardial infarction. One important factor in the final result may be the presence of residual coronary flow supplied by extensive collaterals or by subtotal occlusion of the affected coronary artery when reperfusion is achieved around 4 hours after the onset of symptoms.

  16. The effects of 201Tl myocardial perfusion scintigraphy studies on oxidative damage in patients.

    PubMed

    Cicek, E; Yildiz, M; Delibas, N; Bahçeli, S

    2009-01-01

    The aim of this study was to investigate gamma radiation-induced oxidative damage in erythrocytes after 201Tl myocardial perfusion scintigraphy. Twenty patients (8 women and 12 men) who performed 201Tl myocardial perfusion scintigraphy were included in this study. The blood samples were taken from patients just before, 1 hour after and three hours after injection of the radiopharmaceutical. Malondialdehyde (MDA) and antioxidant enzymes such as glutathione peroxidase (GPX), superoxide dismutase (SOD) and catalase (CAT) levels were measured to evaluate the gamma radiation induced oxidative damage. The enzyme activities of SOD, GPX and CAT were decreased 1 hour after (p = 0.042, p = 0.697 and p = 0.653 respectively) and 3 hours after (p = 0.003, p = 0.573 and p = 0.002 respectively) injection of the radiopharmaceutical. Malondialdehyde levels were increased 1 hour after (p = 0.10) and 3 hours after (p = 0.47) injection of the radiopharmaceutical. In this study, we found that radiation due to 201Tl myocardial perfusion scintigraphy decreased the erythrocyte antioxidant levels and increased MDA levels.

  17. Clinical relevance of 201Tl-chloride SPET in the differential diagnosis of brain tumours.

    PubMed

    Staffen, W; Hondl, N; Trinka, E; Iglseder, B; Unterrainer, J; Ladurner, G

    1998-04-01

    Magnetic resonance imaging (MRI) and computed tomography (CT) may not be reliable in the differential diagnosis of tumour necrosis, scar and recurrent tumour. We compared 201Tl-chloride SPET with CT and MRI for the differential diagnosis of these cerebral lesions. Brain SPET was performed in 40 patients after the intravenous injection of 201Tl-chloride. All 40 patients also had a CT or MRI scan, and a histological diagnosis was available for 27 of the patients. For each patient, the ratio of counts in the lesion region of interest (ROI) to counts in the contralateral ROI was calculated and found to be between 0.58 and 9.60. The ratios for high-grade gliomas, metastases and meningiomas were high (> 2.7), especially in tumours with good vascularization. A low ratio (< 1.7) was noted in patients with low-grade astrocytoma, necrosis or ischaemic lesions. There were two exceptional cases of ischaemic lesions in the luxury perfusion stage (ratios of 3.61 and 3.87), as verified by HMPAO-SPET. We found that 201Tl-chloride SPET helps to differentiate between malignant tumours, poorly vascularized benign lesions and necrosis. Differentiation between low-grade astrocytoma and non-malignant lesions was not possible, but there was a trend towards differentiating between low-grade astrocytoma and ischaemic infarction. The timing of the investigation is important to avoid false-positive results in hyperperfused ischaemic tissue.

  18. Estimation of potential excess cancer incidence in pediatric 201Tl imaging.

    PubMed

    Kaste, Sue C; Waszilycsak, George L; McCarville, M Beth; Daw, Najat C

    2010-01-01

    Little information is available regarding doses of ionizing radiation from medical imaging in the growing population of children undergoing therapy for cancer who are at risk of developing second cancers. The purpose of our study was to estimate the potential excess lifetime cancer incidence and mortality associated with thallium bone imaging in pediatric patients. We retrospectively reviewed the medical records of pediatric patients treated between August 1991 and December 2003 for newly diagnosed osteosarcoma who underwent 201Tl imaging as part of the treatment protocol. According to age at diagnosis and doses of 201Tl, we estimated the excess cancer incidence and cancer mortality for boys and girls at 5 and 15 years old. The study cohort consisted of 73 patients, 32 males (median age at diagnosis, 14.8 years; age range, 8.1-20.1 years) and 41 females (median age at diagnosis, 13.3 years; age range, 6.0-20.7 years). Patients underwent a total of three 201Tl studies with a median dose of 4.4 mCi (162.8 MBq) (range, 2.2-8.4 mCi [81.4-310.8 MBq]) per study. Total median cumulative patient radiation dose for 201Tl studies was 18.6 rem (186 mSv) (range, 8.4-44.2 rem [84-442 mSv]) for males and 21.5 rem (215 mSv) (range, 7.0-43.8 rem [70-438 mSv]) for females. Estimated excess cancer incidence was 6.0 per 100 (male) and 13.0 per 100 (female) if exposed by 5 years of age; 2.0 per 100 (male) and 3.1 per 100 (female) by 15 years of age. Estimated excess cancer mortality was 3.0 per 100 for males and 5.2 per 100 for females at 5 years of age; 1.0 per 100 (male) and 1.4 per 100 (female) exposed at 15 years of age. Further reduction of doses in younger patients is needed to consider 201Tl a viable option for imaging osteosarcoma.

  19. NOTE: Comparison of correction techniques for simultaneous 201Tl/99mTc myocardial perfusion SPECT imaging: a dog study

    NASA Astrophysics Data System (ADS)

    Knesaurek, Karin; Machac, Josef

    2000-11-01

    We compared two correction methods for simultaneous 201Tl/99mTc dual-isotope single-photon emission computed tomography (SPECT). Both approaches use the information from the third energy window placed between the photopeak windows of the 201Tl and 99mTc. The first approach, described by Moore et al, corrects only for the contribution of the 99mTc to the 201Tl primary 70 keV window. We developed the three-window transformation dual-isotope correction method, which is a simultaneous cross-talk correction. The two correction methods were compared in a simultaneous 201Tl/99mTc sestamibi cardiac dog study. Three separate acquisitions were performed in this dog study: two single-isotope and one dual-isotope acquisition. The 201Tl single-isotope images were used as references. The total number of counts, and the contrast between the left ventricular cavity (LVC) and the myocardium, were used in 70 keV short-axis slices as parameters for evaluating the results of the dual-isotope correction methods. Three consecutive short-axis slices were used to calculate averaged contrast and the averaged total number of counts. The total number of the counts was 667 000 ± 500 and 414 500 ± 400 counts for the dual-isotope (201Tl + 99mTc) and single-isotope (201Tl-only) 70 keV images, respectively. The corrected dual-isotope images had 514 700 ± 700 and 368 000 ± 600 counts for Moore's correction and our approach, respectively. Moore's method improved contrast in the dual-isotope 70 keV image to 0.14 ± 0.03 from 0.11 ± 0.02, which was the value in the 70 keV non-corrected dual-isotope image. Our method improved the same contrast to 0.22 ± 0.03. The contrast in the 201Tl single-isotope 70 keV image was 0.28 ± 0.02. Both methods improved the 70 keV dual-isotope images. However, our approach provided slightly better images than Moore's correction when compared with 201Tl-only 70 keV images.

  20. Activity determination of a 201Tl solution by 4πβ-γ and sum-peak coincidence methods

    NASA Astrophysics Data System (ADS)

    Ruzzarin, A.; da Silva, M. A. L.; Iwahara, A.; da Silva, R. L.; Filho, O. L. T.; Poledna, R.; Lopes, R. T.

    2016-07-01

    201Tl is used in nuclear medicine in cardiac imaging for evaluating the injury level in cardiac muscle at rest and exercise. In this work the activity concentration of a 201 Tl radioactive solution has been absolutely determined using the 4πβ-γ coincidence and sum-peak coincidence methods. The presence of 202Tl radioactive impurity that imposes some difficult in the activity measurements was taken into account in the measurements. In the sum-peak method a planar germanium detector was used. The half-lives were evaluated by the reference source method and the results obtained were (3.033 ± 0.004) d and (12.320 ± 0.163) d, respectively, for 201Tl and 202Tl.

  1. A noninvasive method for evaluating portal circulation by administration of /sup 201/Tl per rectum

    SciTech Connect

    Tonami, N.; Nakajima, K.; Hisada, K.; Tanaka, N.; Kobayashi, K.

    1982-11-01

    A new method for evaluating portal systemic circulation by administration of /sup 201/Tl per rectum was performed in 13 control subjects and in 65 patients with various liver diseases. In normal controls, the liver was visualized on the 0--5-min image whereas the images of other organs such as the heart, spleen, and lungs were very poor. In patients with liver cirrhosis associated with portal-systemic shunt, and in many other patients with hepatocellular damage, the liver was not so clearly visualized, whereas radioactivity in other organs, especially the heart, became evident. The heart-to-liver uptake ratio at 20 min after administration (H/L ratio) was significantly higher in liver cirrhosis than in normals and patients with chronic hepatitis (p less than 0.001). The patients with esophageal varices showed a significantly higher H/L ratio compared with that in cirrhotic patients without esophageal varices (p less than 0.001). The H/L ratio also showed a significant difference (p less than 0.01) between Stage 1 and Stage 3 esophageal varices. Since there were many other patients with hepatocellular damage who had high H/L ratios similar to those in liver cirrhosis, the effect that hepatocellular damage has on the liver uptake of /sup 201/Tl is also considered. Our present data suggest that this noninvasive method seems to be useful in evaluating portal-to-systemic shunting.

  2. Comparison of myocardial /sup 201/Tl clearance after maximal and submaximal exercise: implications for diagnosis of coronary disease: concise communication

    SciTech Connect

    Massie, B.M.; Wisneski, J.; Kramer, B.; Hollenberg, M.; Gertz, E.; Stern, D.

    1982-05-01

    Recently the quantitation of regional /sup 201/Tl clearance has been shown to increase the sensitivity of the scintigraphic detection of coronary disease. Although /sup 201/Tl clearance rates might be expected to vary with the degree of exercise, this relationship has not been explored. We therefore evaluated the rate of decrease in myocardial /sup 201/Tl activity following maximal and submaximal stress in seven normal subjects and 21 patients with chest pain, using the seven-pinhole tomographic reconstruction technique. In normals, the mean /sup 201/Tl clearance rate declined from 41% +/- 7 over a 3-hr period with maximal exercise to 25% +/- 5 after 3 hr at a submaximal level (p less than 0.001). Similar differences in clearance rates were found in the normally perfused regions of the left ventricle in patients with chest pain, depending on whether or not a maximal end point (defined as either the appearance of ischemia or reaching 85% of age-predicted heart rate) was achieved. In five patients who did not reach these end points, 3-hr clearance rates in uninvolved regions averaged 25% +/- 2, in contrast to a mean of 38% +/- 5 for such regions in 15 patients who exercised to ischemia or an adequate heart rate. These findings indicate that clearance criteria derived from normals can be applied to patients who are stressed maximally, even if the duration of exercise is limited, but that caution must be used in interpreting clearance rates in those who do not exercise to an accepted end point.

  3. Quantification of myocardial blood flow using (201)Tl SPECT and population-based input function.

    PubMed

    Koshino, Kazuhiro; Fukushima, Kazuhito; Fukumoto, Masaji; Hori, Yuki; Moriguchi, Tetsuaki; Zeniya, Tsutomu; Nishimura, Yoshihiro; Kiso, Keisuke; Iida, Hidehiro

    2014-11-01

    Thallium-201 ((201)Tl) single photon emission computed tomography (SPECT) is an important tool in the diagnosis of ischemic heart disease. Absolute quantification of myocardial blood flow (MBF) has the potential to provide more useful information on myocardial perfusion than semi-quantitative assessments. This study aimed to validate the quantification of MBF using (201)Tl cardiac SPECT based on a population-averaged input function (STD-IF) and one-point blood sample technique. (201)Tl emission and computed tomography (CT)-based attenuation scans were performed on 11 healthy volunteers at rest using a SPECT/CT scanner. Individual input functions (IND-IFs) during the emission scans were based on arterial blood samples. The STD-IF technique was validated as follows: (1) optimal time to calibrate a STD-IF was determined to minimize differences between the calibrated STD-IF and the IND-IFs. (2) Tissue time-activity curves (TTACs) were generated based on a single-tissue compartment model for MBFtrue = 0.5, 1.0, 1.5, and 2.0 mL/min/g, a constant distribution volume of 45 mL/mL, and IND-IFs. The pseudo STD-IF for each subject was generated using the leave-one-out technique. Using the optimal calibration time and the pseudo STD-IFs, MBF values were estimated on the TTACs with an autoradiography method. Optimal mid-scan time (MST) with a fixed duration of 20 min was determined to minimize intersubject variation in estimated MBF errors, and (3) Global and regional MBF values estimated with pseudo STD-IFs were compared to those with IND-IFs using the optimal calibration time and MST. The optimal calibration time and MST were both 20 min after (201)Tl injection. Global MBF determined using both IND-IFs and pseudo STD-IF showed significant correlations with rate-pressure products, R (2) = 0.645; p < 0.01 and R (2) = 0.303; p < 0.05, respectively. The mean percent error in regional MBF using pseudo STD-IFs was 0.69 ± 7.80 % (-12.80 to 14.25 %). No significant

  4. A rapid improved method for gamma-spectrometric determination of 202Tl impurities in [201Tl]-labelled radiopharmaceuticals.

    PubMed

    Bonardi, Mauro; Groppi, Flavia; Birattari, Claudio

    2002-11-01

    Despite the cyclotron production method and the efficiency of the radiochemical procedures adopted, the long-lived radio-isotopic impurity 202Tl is always present in [201Tl]-labelled radio-pharmaceuticals, together with other short-lived impurities like, 200Tl. Rapid determination of the 202Tl impurity, can be achieved using HPGe gamma spectrometry and a detector shielded by a 5 mm thick envelope of lead. In this way, dead-time correction errors, Compton and X-ray background, are very efficiently avoided and suppressed. The same method could be applied routinely in nuclear medicine, to determine the radioisotopic purity of 201Tl by means of an ionisation chamber dose calibrator.

  5. Contamination and radiation exposure from sup 201 Tl in patients undergoing dialysis after a nuclear medicine study

    SciTech Connect

    Serrano, M.; Olson, A.; Man, C.; Galonsky, R.; Stein, R. )

    1991-03-01

    Our institution is a major kidney research and transplant center. Hemodialysis patients that are scheduled for renal transplant are given a 201Tl stress test. Possible radiation exposure and contamination are of concern to attending personnel. We investigated this situation and found measurable activity in the effluent of patients receiving dialysis but no significant contamination of equipment. We determined that dialysis personnel received minimal radiation exposure.

  6. Accuracy of serial myocardial perfusion scintigraphy with /sup 201/Tl for prediction of graft patency early and late after coronary artery bypass surgery. A controlled prospective study

    SciTech Connect

    Pfisterer, M.; Emmenegger, H.; Schmitt, H.E.; Mueller-Brand, J.; Hasse, J.; Graedel, E.; Laver, M.B.; Burckhardt, D.; Burkart, F.

    1982-11-01

    To assess the accuracy of serial myocardial perfusion scintigraphy with /sup 201/Tl to predict graft patency early and late coronary artery bypass surgery, rest and exercise /sup 201/Tl and coronary arteriography were performed preoperatively and 2 weeks and 1 year after operation. The scintigraphic results were compared with graft patency, symptoms, left ventricular function and physical work capacity in a consecutive series of 55 patients with a total of 154 grafts. Serial /sup 201/Tl had an 80% sensitivity, 88% specificity and 86% overall accuracy in detecting or excluding graft occlusion, which was predicted by reversible ischemia as well as persistent new scar segments. Occluded grafts were correctly localized by /sup 201/Tl scintigraphy in 61%. Postoperative apical /sup 201/Tl defects were frequent (two-thirds of cases), and were the result of intraoperative transapical venting of the left ventricle. After coronary bypass graft surgery, ejection fraction at rest was unchanged. Left ventricular end-diastolic pressure and physical work capacity improved significantly. In the presence of new perfusion defects detected postoperatively, physical work capacity was reduced significantly. New /sup 201/Tl defects in addition to typical or atypical angina provided a high probability of graft occlusion, while in the absence of new /sup 201/Tl defects all grafts were patent in more than 90% of patients, all of whom had no or only atypical chest pain. We conclude that serial /sup 201/Tl imaging after coronary artery bypass surgery is an accurate noninvasive method that can be used routinely to assess graft function, to localize spatially occluded grafts and to identify patients with a high likelihood of graft occlusion who may need invasive studies.

  7. Effect of coronary blood flow on uptake and washout of /sup 99m/Tc DMPE and /sup 201/Tl

    SciTech Connect

    Nishiyama, H.; Adolph, R.J.; Deutsch, E.

    1982-12-01

    After intravenous administration of /sup 99m/Tc DMPE the flow-dependent kinetics were studied in dogs during induced ischemia and during induced maximal reactive hyperemia. A control group was also studied. Mean time-activity curves obtained from the myocardial wall were compared within the same intervention group and also with other groups. During reactive hyperemia, there was a rapid and absolute increase in uptake followed by a rapid washout, whereas during ischemia there was a slow and decreased uptake followed by a slow washout. The magnitude of /sup 99m/Tc DMPE uptake during reactive hyperemia was slightly less than that of /sup 201/Tl, but the decreased uptake with ischemia was about equal for the two agents. Following maximal uptake in the myocardium the effective half-life of /sup 99m/Tc DMPE was one-third to one-fourth that of /sup 201/Tl. The similar kinetics of /sup 99m/Tc DMPE compared to /sup 201/Tl suggests its usefulness in the evaluation of ischemic heart disease.

  8. 201Tl heart-liver radioactivity uptake ratio and prediction of decompensation in patients with cirrhosis.

    PubMed

    Lee, Min-Ho; Tae, Hae-Jin; Jun, Dae-Won; Ryu, Seong-Eon; Choi, Yun-Young; Kwak, Min-Jeong; Kang, Ju-Seop

    2013-03-01

    The present study aimed to determine the predictive value of the heart-liver uptake ratio (H/L ratio) of rectally administered (201)Tl scintigraphy for hepatic decompensation, which was conducted in 107 patients with cirrhosis. We retrospectively assessed the predictive value of a noninvasive parameter, H/L ratio, for decompensation during a median follow-up period of 45.4 months using follow-up data from 1996 through 2008 for 107 patients with compensated cirrhosis. Logistic regression analysis and odds ratio estimates were used to estimate independent value of the H/L ratio on the risk of decompensation with 95% confidence intervals. At first visit, all subjects were confirmed as patients with compensated cirrhosis, 39 by liver biopsy and 68 by standard laboratory and radiological criteria. At end of the evaluation time, 81 patients remained compensated, whereas 26 patients decompensated as evidenced by ascites in 23, hepatic encephalopathy in 8, and variceal bleeding in 1 patient. First-visit parameters except bilirubin level, alanine aminotransferase (ALT), and H/L ratio and last visit parameters except ALT and aspartate aminotransferase-ALT ratio were significantly different between the 2 groups as ascertained by Wilcoxon rank sum test (P < 0.05). Among those parameters, we found that the last visit H/L ratio was a strongly reliable predictor of decompensation with an odds ratio estimates of 14.443, area under the receiver operating characteristic curve of 0.825, cutoff of 0.4, sensitivity of 73.1 %, and specificity of 71.6%. This evidence indicates that in patients with compensated cirrhosis, an increased H/L ratio at follow-up may be a useful predictive parameter showing a high risk of progression to a decompensated state.

  9. Voxel-based analysis of (201)Tl SPECT for grading and diagnostic accuracy of gliomas: comparison with ROI analysis.

    PubMed

    Kuwako, Tomoyuki; Mizumura, Sunao; Murakami, Ryusuke; Yoshida, Tamiko; Shiiba, Masato; Sato, Hidetaka; Fukushima, Yoshimitsu; Teramoto, Akira; Kumita, Shin-Ichiro

    2013-07-01

    The aim of this retrospective study was to assess the utility of a voxel-based analysis (VBA) method for (201)Tl SPECT in glioma, compared to conventional ROI analysis. We recruited 24 patients with glioma (high-grade 15; low-grade 9), for whom pre-operative (201)Tl SPECT and MRI were performed. SPECT images were coregistered with MRI. The uptake ratio (UR) images of tumor to contralateral normal tissue were measured on early and delayed images, and the (201)Tl retention index (RI) map was calculated from the early and delayed uptake ratio maps. In the ROI analysis, tumors were traced on a UR map, and the mean and maximal uptake ratio values on the early images were, respectively, defined as the mean and maximal UR. The mean and maximal RI values (mean and maximal RI) were calculated by division of the mean and maximal UR, respectively, on the delayed image by the mean and maximal UR on the early image. For the RI map calculated voxel by voxel, the maximal RI value was defined as VBA-RI. We evaluated sensitivity and accuracy of differential analysis with the mean and maximal UR, RI, and VBA-RI. The high- and low-grade groups showed no significant difference in mean and maximal RI (0.98 ± 0.12 vs. 1.05 ± 0.09 and 0.98 ± 0.18 vs. 1.05 ± 0.14, respectively). The AUC and accuracy of the mean and maximal RI were 0.681 and 66.7 %, and 0.622 and 62.5 %, respectively. In contrast, VBA-RI was higher in high-grade than in low-grade glioma (1.69 ± 0.27 vs. 0.68 ± 0.66, p < 0.001). The AUC and accuracy of VBA-RI were 0.963 and 95.8 %, which are higher than those obtained for mean (p < 0.05) and maximal RI (p < 0.01). There was no significant difference in ROC between the VBA-RI and the mean UR (0.911, p = 0.456) and maximal UR (0.933, p = 0.639); however, the AUC, sensitivity, and diagnostic accuracy of VBA-RI were all higher than those of the mean and maximal UR. The voxel-based analysis method of (201)Tl SPECT may improve diagnostic performance for gliomas, compared

  10. Clinical implications of increased lung uptake of /sup 201/Tl during exercise scintigraphy 2 weeks after myocardial infarction

    SciTech Connect

    Gibson, R.S.; Watson, D.D.; Carabello, B.A.; Holt, N.D.; Beller, G.A.

    1982-05-01

    To determine the prevalence and clinical significance of increased lung /sup 201/Tl uptake during submaximal exercise myocardial scintigraphy performed 2 weeks after acute myocardial infarction, 61 patients underwent submaximal exercise testing (target heart rate, 120 beats/min), multigated blood pool imaging at rest and coronary angiography before hospital discharge. Thallium lung uptake on the initial anterior projection image was graded qualitatively by comparing the intensity of /sup 201/Tl activity in the lungs with that in the mediastinum. In 39 patients (64 percent), it was normal (equal to mediastinal activity) and in 22 (36 percent), it was increased (greater than mediastinal activity). Compared with patients with normal lung uptake, those with increased uptake had a greater prevalence of prior infarction (13 versus 36 percent, probability (p) less than 0.05), less global cardiac reserve as assessed by the four level New York Heart Association classification (p less than 0.05), more advanced Killip class in the coronary care unit (p less than 0.05), a higher Norris coronary prognostic index (2.6 +/- 1.9 versus 4.6 +/- 2.3 (mean +/- standard deviation), p less than 0.01), failure to achieve the target heart rate because of dyspnea, fatigue or angina (36 versus 86 percent, p less than 0.01), a greater prevalence of exercise-induced S-T segment depression (18 versus 45 percent, p less than 0.05), a greater number of anterior /sup 201/Tl myocardial defects (p less than 0.05); a lower radionuclide ejection fraction at rest (50.4 +/- 6.1 versus 39.6 +/- 9.3 percent, p less than 0.01) and a greater number of asynergic left ventricular segments (p less than 0.05). Thus, the occurrence of increased lung /sup 201/Tl uptake during submaximal exercise scintigraphy in the early postinfarction period is frequent and appears to be a marker of severe and functionally more important coronary artery disease associated with left ventricular dysfunction.

  11. Assessment of resistance to paclitaxel of murine tumors by (99m)Tc-MIBI/(201)Tl dual-radionuclide imaging.

    PubMed

    Oriuchi, N; Jibu, T; Milas, L; Choe, J; Kuang, L; Kim, E E; Hunter, N R; Wallace, S; Podoloff, D A

    2000-02-01

    This study investigated P-glycoprotein (Pgp) expression by murine tumors with and without resistance to paclitaxel and the role of (99m)Tc-2-methoxyisobutylisonitrile (MIBI)/(201)Tl imaging in predicting the effect of paclitaxel. Antitumor effect of paclitaxel and biodistribution of the radiopharmaceuticals were evaluated in mice bearing four tumor types. Pgp expression did not correlate with the antitumor efficacy of paclitaxel. Although the absolute uptake of (99m)Tc-MIBI did not correlate with Pgp expression, (99m)Tc-MIBI could predict paclitaxel sensitivity by its higher uptake.

  12. Detection of coronary artery stenosis in children with Kawasaki disease. Usefulness of pharmacologic stress sup 201 Tl myocardial tomography

    SciTech Connect

    Kondo, C.; Hiroe, M.; Nakanishi, T.; Takao, A. )

    1989-09-01

    This study determined the feasibility and accuracy of quantitative 201Tl myocardial single-photon emission computed tomography (SPECT) after dipyridamole infusion to detect coronary obstructive lesions in children with Kawasaki disease. 201Tl distribution after dipyridamole infusion was measured in 23 normal children, and with these normal values, quantitative analysis of SPECT was performed in 49 patients. Thirty-four patients had coronary stenosis 90% or greater on angiograms. Side effects resulting from systemic vasodilation were observed in about 70%. Angina pectoris and ischemic ST changes were observed only in patients with coronary stenosis. These symptoms disappeared after aminophylline infusion. Results of visual and quantitative analysis of SPECT were compared. SPECT data were shown on two-dimensional polar maps, and the extent and severity scores were calculated. The sensitivity of SPECT for detection of overall coronary stenosis was 91% (visual analysis) and 88% (quantitative analysis). The specificity of SPECT was 60% visually and 93% quantitatively. The sensitivity of quantitative analysis to detect individual coronary stenosis was similar to that of visual analysis. However, the specificity of visual analysis to detect individual coronary artery stenosis was significantly less than that of quantitative analysis. From these data, we conclude that quantitative analysis of myocardial SPECT after dipyridamole infusion is a safe and accurate diagnostic method for identifying coronary stenosis in children with Kawasaki disease.

  13. Serial right ventricle /sup 201/Tl imaging after exercise: relation to anatomy of the right coronary artery

    SciTech Connect

    Brown, K.A.; Boucher, C.A.; Okada, R.D.; Strauss, H.W.; McKusick, K.A.; Pohost, G.M.

    1982-12-01

    The relation of the appearance of the right ventricle on serium /sup 201/Tl myocardial imaging to coronary artery anatomy was examined in 88 consecutive patients undergoing exercise /sup 201/Tl testing and coronary angiography for the evaluation of chest pain. Transient defects in the right ventricle were found in 8 patients. All had high grade (greater than or equal to 90%) stenosis of the proximal right coronary artery. Nonvisualization of right ventricular (RV) activity occurred in 10 patients. Nine of the 10 (90%) had significant (greater than or equal to 50% stenosis) disease of the proximal right coronary artery and 7 (70%) had high grade stenosis. The right ventricle appeared normal in 70 patients. Twenty-nine (41%) of these patients had significant proximal right coronary artery disease. Right ventricular appearance was not affected by the presence or absence of disease of the left anterior descending or left circumflex artery or by the appearance of the left ventricle. Thus, with serial RV thallium-201 myocardial imaging after exercise, we found that (1) RV transient defects suggest the presence of high grade proximal right coronary artery stenosis, (2) non-visualization of RV activity also predicts significant proximal right coronary disease, and (3) the right ventricle frequently appears normal despite proximal right coronary artery disease and therefore this finding does not exclude such disease.

  14. Noninvasive detection and localization of coronary stenoses in patients: comparison of resting dipyridamole and exercise /sup 201/Tl myocardial perfusion imaging

    SciTech Connect

    Josephson, M.A.; Brown, B.G.; Hecht, H.S.; Hopkins, J.; Pierce, C.D.; Petersen, R.B.

    1982-06-01

    Two noninvasive tests to detect and localize coronary stenoses were compared in a fully blinded protocol. /sup 201/Tl myocardial perfusion imaging (MPI) following maximal treadmill exercise and pharmacologic coronary vasodilation with intravenous dipyridamole (DP) was performed in 33 patients. /sup 201/Tl imaging defects in six myocardial perfusion regions were correlated with stenoses in their respective vascular distributions. Disease severity was determined with coronary arteriograms using a computer-assisted method. 198 myocardial regions were evaluated; 101 were supplied by at least one major artery with a greater than or equal to 50% stenosis (luminal diameter narrowing). The sensitivity and specificity for detecting a greater than or equal to 50% stenosis were 85% and 64% (p less than 0.005), respectively, for DP and 84% and 68% (p less than 0.005) for exercise-/sup 201/Tl imaging. A particular combination of anterior and septal imaging defects was useful in detecting left anterior descending artery stenoses proximal to its first septal branch. DP administration was safe in this group of patients; however, 42% experienced transient chest pain. Although the overall sensitivity and specificity of the two methods were not significantly different, DP-MPI appeared more sensitive than exercise-MPI (70% vs 52%, p less than 0.01) in detecting coronary stenoses in the 40% to 60% range. DP-/sup 201/Tl MPI provides a useful alternative test for potential coronary disease patients unable to perform maximal exercise.

  15. Echocardiography versus (201)Tl semi-quantitative gated single photon emission tomography for the evaluation of cardiac disease associated with late stage Duchenne muscular dystrophy.

    PubMed

    Fujita, Atsushi; Arahata, Hajime; Sugawara, Miwa; Watanabe, Akihiro; Kawano, Yuji; Sasagasako, Naokazu; Fujii, Naoki

    2016-01-01

    In Duchenne muscular dystrophy (DMD) patients cardiac abnormalities are often detected. In adult DMD patients cardiac disease (CD) is a cause of death which increases by age and is related to respiratory dysfunction. Studies have demonstrated that CD in early DMD can be detected by echocardiography (EC) or semi-quantitative gated single photon emission tomography ((201)Tl SQGS), and the accuracy of these two tests is similar. As the disease advances, evaluation of CD by EC becomes difficult due to thoracic deformity and scoliosis. We compared (201)Tl SQGS and EC in the evaluation of cardiac function in late stage DMD, based on the ejection fraction (EF) value calculated by both tests. Twenty-three males with late stage DMD, 12 to 35 years of age (22.2±7.5), were studied by (201)Tl SQGS and EC. The mean EF value by (201)Tl SQGS was 60.8%±14.1%, which differed from that obtained by EC (52.7%±9.8%, P=0.003). Eleven patients less than 20 years old did not demonstrate a significant difference between the two tests (P=0.06), however, 12 patients over 20 years of age had significantly different results between tests (P=0.002). Although our patients were few we indicated that in DMD patients, aged older than 20 years, at an advanced stage of the disease, the EF values calculated by EC were lower than those by (201)Tl SQGS possibly due to thoracic deformity.

  16. Stress/injection protocols for myocardial scintigraphy with 99Tcm-sestamibi compared with 201Tl: implications of early post-stress kinetics.

    PubMed

    Hurwitz, G A; Blais, M; Powe, J E; Champagne, C L

    1996-05-01

    Stress/injection protocols developed for myocardial perfusion imaging with 201Tl may not be optimal for 99Tcm-sestamibi (MIBI), an agent with lower myocardial extraction and higher abdominal uptake; prolongation of exercise after radiotracer injection might improve these relative drawbacks of MIBI. We compared the kinetics of MIBI and 201Tl by acquiring dynamic planar images for 5-7 min after a bolus injection (n = 180 studies) with stress performed by supine bicycle exercise alone, intravenous dipyridamole or combined stress. Routine or prolonged protocols involved continuation of exercise for 1 or 2.5 min respectively after tracer appearance in the heart. Subsequently, the perfusion images obtained were categorized as normal or showing significant defects. Myocardial uptake of MIBI, normalized for injected dose, body weight and camera sensitivity, was only 40% of that for 201Tl; there were no differences based on test mode or scan result for either perfusion tracer. During the second minute after injection, the cavity/myocardial ratios, an index of blood pool activity, were elevated with MIBI by 25% when compared with 201Tl (P < 0.001). During the third minute, cavity activity was again higher with MIBI, but only in those subjects with abnormal scans. The prolonged exercise phase did not prevent progressive accumulation in the abdomen, but did allow cavity levels to decline before termination of exercise. The prolonged protocol may ensure that myocardial uptake of MIBI is completed during peak blood flow, and therefore is recommended for stress with exercise or with dipyridamole and exercise in combination.

  17. KEY COMPARISON: BIPM comparison BIPM.RI(II)-K1.Tl-201 of activity measurements of the radionuclide 201Tl

    NASA Astrophysics Data System (ADS)

    Ratel, G.; Michotte, C.

    2004-01-01

    Since 1979, six national metrology institutes (NMI) and another laboratory have submitted 16 samples of known activity of 201Tl to the International Reference System (SIR) for activity comparison at the Bureau International des Poids et Mesures (BIPM), with comparison identifier BIPM.RI(II)-K1.Tl-201. The activities ranged from about 3.5 MBq to 207 MBq. The degrees of equivalence between each equivalent activity measured in the SIR and the key comparison reference value (KCRV) have been calculated and the results are given in the form of a matrix for six NMIs. A graphical presentation is also given. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by Section II of the Consultative Committee for Ionizing Radiation (CCRI(II)), according to the provisions of the Mutual Recognition Arrangement (MRA).

  18. Monte Carlo evaluation of accuracy and noise properties of two scatter correction methods for /sup 201/Tl cardiac SPECT

    NASA Astrophysics Data System (ADS)

    Narita, Y.; Iida, H.; Ebert, S.; Nakamura, T.

    1997-12-01

    Two independent scatter correction techniques, transmission dependent convolution subtraction (TDCS) and triple-energy window (TEW) method, were evaluated in terms of quantitative accuracy and noise properties using Monte Carlo simulation (EGS4). Emission projections (primary, scatter and scatter plus primary) were simulated for three numerical phantoms for /sup 201/Tl. Data were reconstructed with ordered-subset EM algorithm including noise-less transmission data based attenuation correction. Accuracy of TDCS and TEW scatter corrections were assessed by comparison with simulated true primary data. The uniform cylindrical phantom simulation demonstrated better quantitative accuracy with TDCS than with TEW (-2.0% vs. 16.7%) and better S/N (6.48 vs. 5.05). A uniform ring myocardial phantom simulation demonstrated better homogeneity with TDCS than TEW in the myocardium; i.e., anterior-to-posterior wall count ratios were 0.99 and 0.76 with TDCS and TEW, respectively. For the MCAT phantom, TDCS provided good visual and quantitative agreement with simulated true primary image without noticeably increasing the noise after scatter correction. Overall TDCS proved to be more accurate and less noisy than TEW, facilitating quantitative assessment of physiological functions with SPECT.

  19. Estimation of infarct size by myocardial emission computed tomography with /sup 201/Tl and its relation to creatine kinase-MB release after myocardial infarction in man

    SciTech Connect

    Tamaki, S.; Nakajima, H.; Murakami, T.

    1982-11-01

    We evaluated emission computed tomography (ECT) /sup 201/Tl myocardial imaging in estimating infarct size (IS). In 18 patients in whom IS was estimated enzymatically at the time of the acute episode, planar /sup 201/Tl perfusion scintigraphy and ECT with a rotating gamma camera were performed 4 weeks after the first myocardial infarction. From the size of /sup 201/Tl perfusion defects, the infarct area in planar images and the infarct volume in reconstructed ECT images were measured by computerized planimetry. When scintigraphic IS was compared with the accumulated creatine kinase-MB isoenzyme release (CK-MBr), infarct volume determined from ECT correlated closely with CK-MBr (r . 0.89), whereas infarct area measured from planar images correlated less satisfactorily with the enzymatic IS (for an average infarct area from three views, r . 0.69; for the largest infarct area, r . 0.73). Although conventional scintigraphic evaluation is useful for detecting and localizing infarction, quantification of ischemic injury with this two-dimensional technique has a significant inherent limitation. The ECT approach can provide a more accurate three-dimensional quantitative estimate of infarction, and can corroborate the enzymatic estimate of IS.

  20. Dielectric properties and charge transfer in (TlInSe2)0.1(TlGaTe2)0.9 for the DC and AC current

    NASA Astrophysics Data System (ADS)

    Mustafaeva, S. N.; Asadov, M. M.; Dzhabbarov, A. I.

    2014-06-01

    The experimental results of studying the temperature and frequency dependences of dc and ac conductivity as well as the dispersion of dielectric coefficients of the grown single crystals of the (TlInSe2)0.1(TlGaTe2)0.9 solid solution are presented. The nature of dielectric losses and the hopping charge transfer mechanism have been established, and parameters of localized states, such as the density of states near the Fermi level and their spread, the average time and the hopping length of charge carriers, and the concentration of deep traps responsible for dc and ac conductivity, have been evaluated.

  1. Serial /sup 201/Tl myocardial imaging after dipyridamole infusion: diagnostic utility in detecting coronary stenoses and relationship to regional wall motion

    SciTech Connect

    Leppo, J.; Boucher, C.A.; Okada, R.D.; Newell, J.B.; Strauss, H.W.; Pohost, G.M.

    1982-09-01

    After a 4-minute i.v. dipyridamole infusion, 0.14 mg/kg/min, serial /sup 201/Tl scans were obtained in 60 patients undergoing cardiac catheterization. Forty patients had significant (greater than or equal to 50% stenosis) coronary artery disease (CAD), and 20 patients had normal coronary arteries or trivial lesions. The images were graded qualitatively for thallium activity by three observers. Sensitivity was 93% (37 of 40) and specificity was 80% (16 of 20). The sensitivity and specificity of the /sup 201/Tl study were not affected by the extent of CAD, the presence of Q waves, or propranolol therapy. Twenty-seven of 37 patients who had initial defects (73%) had complete thallium redistribution of one or more defects. Patient-by-patient analysis using a regression model of all patients showed that the fate of a segmental thallium defect predicted abnormal wall motion by angiography better than ECG Q waves. The presence of propranolol therapy or collaterals did not significantly affect the thallium redistribution results. We conclude that qualitative interpretation by multiple observers of thallium images after dipyridamole infusion is a highly sensitive and specific test for CAD. After dipyridamole, as with exercise stress, the extent of thallium redistribution is related to the degree of myocardial wall motion abnormality.

  2. Using adaptive neuro-fuzzy inference system technique for crosstalk correction in simultaneous 99mTc/201Tl SPECT imaging: A Monte Carlo simulation study

    NASA Astrophysics Data System (ADS)

    Heidary, Saeed; Setayeshi, Saeed

    2015-01-01

    This work presents a simulation based study by Monte Carlo which uses two adaptive neuro-fuzzy inference systems (ANFIS) for cross talk compensation of simultaneous 99mTc/201Tl dual-radioisotope SPECT imaging. We have compared two neuro-fuzzy systems based on fuzzy c-means (FCM) and subtractive (SUB) clustering. Our approach incorporates eight energy-windows image acquisition from 28 keV to 156 keV and two main photo peaks of 201Tl (77±10% keV) and 99mTc (140±10% keV). The Geant4 application in emission tomography (GATE) is used as a Monte Carlo simulator for three cylindrical and a NURBS Based Cardiac Torso (NCAT) phantom study. Three separate acquisitions including two single-isotopes and one dual isotope were performed in this study. Cross talk and scatter corrected projections are reconstructed by an iterative ordered subsets expectation maximization (OSEM) algorithm which models the non-uniform attenuation in the projection/back-projection. ANFIS-FCM/SUB structures are tuned to create three to sixteen fuzzy rules for modeling the photon cross-talk of the two radioisotopes. Applying seven to nine fuzzy rules leads to a total improvement of the contrast and the bias comparatively. It is found that there is an out performance for the ANFIS-FCM due to its acceleration and accurate results.

  3. Microvascular obstruction on delayed enhancement cardiac magnetic resonance imaging after acute myocardial infarction, compared with myocardial (201)Tl and (123)I-BMIPP dual SPECT findings.

    PubMed

    Mori, Hiroaki; Isobe, Satoshi; Sakai, Shinichi; Yamada, Takashi; Watanabe, Naoki; Miura, Manabu; Uchida, Yasuhiro; Kanashiro, Masaaki; Ichimiya, Satoshi; Okumura, Takahiro; Murohara, Toyoaki

    2015-08-01

    The hypo-enhanced regions within the hyper-enhanced infarct areas detected by cardiac magnetic resonance (CMR) imaging reflect microvascular obstruction (MO) after acute myocardial infarction (AMI). The combined myocardial thallium-201 ((201)Tl)/iodine-123-15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid ((123)I-BMIPP) dual single-photon emission computed tomography (SPECT) is a useful tool for detecting myocardial reversibility after AMI. We evaluated whether MO could be an early predictor of irreversible myocardial damage in comparison with (201)Tl and (123)I-BMIPP dual SPECT findings in AMI patients. Sixty-two patients with initial AMI who successfully underwent coronary revascularization were enrolled. MO was defined by CMR imaging. Patients were divided into 2 groups as follows: MO group (n=32) and non-MO group (n=30). Scintigraphic defect scores were calculated using a 17-segment model with a 5-point scoring system. The mismatch score (MMS) was calculated as follows: the total sum of (Σ) (123)I-BMIPP defect score minus Σ(201)Tl defect score. The percentage mismatch score (%MMS) was calculated as follows: MMS/(Σ(123)I-BMIPP score)×100 (%). The percentage infarct size (%IS) was significantly greater in the MO group than in the non-MO group (32.2±13.8% vs. 18.3±12.1%, p<0.001). The %MMS significantly correlated with the %IS and the percentage MO (r=-0.26, p=0.03; r=-0.45, p<0.001, respectively). The %MMS was significantly greater in the non-MO group than in the MO group (45.4±42.4% vs. 13.3±28.0%, p=0.001), and was an independent predictor for MO (OR 0.97, 95%CI 0.94-0.99, p=0.02). Our results reconfirm that, in comparison with myocardial dual scintigraphy, MO is an important structural abnormality. CMR imaging is useful for the early detection of irreversible myocardial damage after AMI. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  4. Validation and evaluation of model-based crosstalk compensation method in simultaneous /sup 99m/Tc stress and /sup 201/Tl rest myocardial perfusion SPECT

    NASA Astrophysics Data System (ADS)

    Song, X.; Frey, E. C.; Wang, W. T.; Du, Y.; Tsui, B. M. W.

    2004-02-01

    Simultaneous acquisition of /sup 99m/Tc stress and /sup 201/Tl rest myocardial perfusion SPECT has several potential advantages, but the image quality is degraded by crosstalk between the Tc and Tl data. We have previously developed a crosstalk model that includes estimates of the downscatter and Pb X-ray for use in crosstalk compensation. In this work, we validated the model by comparing the crosstalk from /sup 99m/Tc to the Tl window calculated using a combination of the SimSET-MCNP Monte Carlo simulation codes. We also evaluated the model-based crosstalk compensation method using both simulated data from the 3-D MCAT phantom and experimental data from a physical phantom with a myocardial defect. In these studies, the Tl distributions were reconstructed from crosstalk contaminated data without crosstalk compensation, with compensation using the model-based crosstalk estimate, and with compensation using the known true crosstalk, and were compared with the Tl distribution reconstructed from uncontaminated Tl data. Results show that the model gave good estimates of both the downscatter photons and Pb X-rays in the simultaneous dual-isotopes myocardial perfusion SPECT. The model-based compensation method provided image quality that was significantly improved as compared to no compensation and was very close to that from the separate acquisition.

  5. Decontamination of rat and human skin experimentally contaminated with (99m)Tc, (201)Tl and (131)I radionuclides using "Dermadecon" - a skin decontamination kit: an efficacy study.

    PubMed

    Nishad, Dhruv Kumar; Bhalla, Supriya; Khanna, Kushagra; Sharma, Braj Gaurav; Rawat, Harish Singh; Mittal, Gaurav; Bhatnagar, Aseem

    2017-05-03

    Radioactive skin contamination is one of the most likely risks which occurs after accidental or occupational radiological accidents apart from internal contamination. In such cases where the radioactive contamination has occurred, the person who is contaminated should be decontaminated as early as possible to reduce the damaging health effects of radiation. In the present study, the decontamination efficiency of a developed skin decontamination kit "dermadecon" has been evaluated in animal models and human subjects using gamma scintigraphy. Decontamination efficiency (percentage of the radioactive contaminant removed) was calculated for each radioactive isotope of the study and compared with control where general washing procedure was followed using liquid and soap. The effectiveness of the kit was calculated in animal model with respect to (99m)Tc-sodium-pertechnetate ((99m)TcO(4-)), (201)TlCl and (131)I and was found 92.84 ± 4.9%, 91.18 ± 3.23% and 94.67 ± 2.92%, respectively. Whereas, in case of human skin, the decontamination efficiency for (99m)TcO(4-) was observed to be 95.00 ± 3.21%. On the basis of findings from the study, it can be concluded that the decontamination agents of the used skin decontamination kit are effective for removal of localized radioactive contaminants from skin, as compared with normal decontamination using soap and water.

  6. Quantification of infarct size by /sup 201/Tl single-photon emission computed tomography during acute myocardial infarction in humans. Comparison with enzymatic estimates

    SciTech Connect

    Mahmarian, J.J.; Pratt, C.M.; Borges-Neto, S.; Cashion, W.R.; Roberts, R.; Verani, M.S.

    1988-10-01

    We prospectively investigated whether /sup 201/Tl single-photon emission computed tomography (SPECT) could accurately diagnose the presence and quantify the extent of acute myocardial infarction when compared with infarct size assessed by plasma MB-creatine kinase activity. Thirty patients with enzymatic evidence of infarction were imaged within 12-36 hours of chest pain (mean, 23.4 hours). No patient had a previous infarction, and none underwent intervention seeking to restore coronary patency. Infarct size was quantified with computer-generated polar maps of the myocardial radioactivity and expressed as a percentage of the total left ventricular volume. To assess left and right ventricular performance, blood-pool gated radionuclide angiography was performed immediately after SPECT. All 30 patients had perfusion defects consistent with myocardial infarction. Scintigraphic and enzymatic estimates of infarct size correlated well for the group as a whole (r = 0.78, p less than 0.001, SEE = 9.1) but especially for those patients with anterior infarction (r = 0.91, p less than 0.001, SEE = 7.9). The poor correlation observed in patients with inferior infarction (r = 0.50, p less than 0.05, SEE = 10.0) was believed to be related to the frequent occurrence of right ventricular involvement because SPECT assessed only left ventricular damage, whereas the enzymatic method estimated the myocardial injury in both ventricles. A quantitative index of right ventricular infarct size, derived from the relation between the scintigraphic and enzymatic estimates, had a strong inverse correlation with right ventricular ejection fraction (r = -0.89, p less than 0.001, SEE = 3.6).

  7. [The significance of 201Tl/123I MIBG (metaiodobenzylguanidine) mismatched myocardial regions for predicting ventricular tachycardia in patients with idiopathic dilated cardiomyopathy].

    PubMed

    Maeno, M; Ishida, Y; Shimonagata, T; Hayashida, K; Toyama, T; Hirose, Y; Nagata, M; Miyatake, K; Uehara, T; Nishimura, T

    1993-10-01

    123I-MIBG (MIBG) regional defects in myocardial regions with preserved 201Tl (Tl) uptake have been observed in patients with idiopathic dilated cardiomyopathy (DCM). To evaluate whether the presence of Tl/MIBG mismatched regions is related to the occurrence of ventricular tachycardia (VT), we performed myocardial dual SPECT imaging with Tl (111 MBq) and MIBG (111 MBq) in 17 patients with DCM, 11 (Gp A) with and 6 (Gp B) without VT. Myocardial dual SPECT imaging was performed at 15 minutes after and 4 hours after the tracer injection. The regional tracer uptake was scored visually in 6 segments of the basal, middle, and apical short-axial images and in 2 apical segments of the midventricular vertical long-axial image by a four-point scoring system (0 = normal, 1 = moderate, 2 = severe and 3 = complete defect). Then, the severity of tracer maldistributions was assessed by the difference between total defect scores (TDSs) of Tl and MIBG (delta TDS). TDS was not different between Gps A and B in both Tl and MIBG images. However, delta TDS was larger in Gp A than in Gp B (13.5 +/- 6.5 vs. 5.8 +/- 3.0, p < 0.05). Also, the number of segments with the mismatched tracer uptake was larger in Gp A than in Gp B (12.5 +/- 3.0 vs. 8.3 +/- 1.5, p < 0.01). In the electrophysiologic study, we found that the fractionated area corresponded to the mismatched region in 3 of 5 patients in Gp A. These results suggest that regional sympathetic denervation is a possible factor which provocates VT, and myocardial dual SPECT imaging with Tl and MIBG is a useful method for predicting VT in patients with DCM.

  8. Usefulness of the Chang attenuation correction method with use of a CT-based μ map by FBP reconstruction in (201)Tl SPECT-MPI.

    PubMed

    Nakamura, Yuya; Tomiguchi, Seiji

    2015-06-01

    Attenuation correction (AC) on nuclear images of non-uniform domains is generally performed by a change of the computed tomography (CT) values to μ values, which are then inserted as components into the detection probability of iterative reconstruction techniques (OS-EM Iterative AC). We established an AC technique which uses a CT μ map based on the Chang AC. Our purpose in this study was to confirm the appropriateness of the Chang AC with the OS-EM and the FBP method (OS-EM Chang AC and FBP Chang AC) by evaluating the results obtained in a phantom and clinical study for (201)Tl single-photon emission-computed tomography-myocardial perfusion imaging (SPECT-MPI). Myocardial phantom study and retrospective clinical study were performed. Evaluations for image quality (uniformity and contrast) and image quantitative values [accurate left ventricular (LV) volume and radioactivity] were performed for both studies. FBP Chang AC showed good image uniformity and proper contrast in phantom and clinical study. Accurate LV volume and radioactivity in the myocardium were also obtained by the phantom study. On the other hand, the number of iterations influenced the image quality both in OS-EM Iterative AC and OS-EM Chang AC in the phantom study. Different numbers of iterations were necessary for obtaining good contrast ratio in each of the anterior and inferior wall, and accurate LV volume. The number of iterations influences the image quality and quantitative values on OS-EM Iterative Chang AC and OS-EM Chang AC images. In addition, it is difficult to set an appropriate number of iterations for the iterative reconstruction of these images in phantom and clinical studies. Therefore, FBP Chang AC is considered to be clinically useful.

  9. Comparison of an adaptive neuro-fuzzy inference system and an artificial neural network in the cross-talk correction of simultaneous 99 m Tc / 201Tl SPECT imaging using a GATE Monte-Carlo simulation

    NASA Astrophysics Data System (ADS)

    Heidary, Saeed; Setayeshi, Saeed; Ghannadi-Maragheh, Mohammad

    2014-09-01

    The aim of this study is to compare the adaptive neuro-fuzzy inference system (ANFIS) and the artificial neural network (ANN) to estimate the cross-talk contamination of 99 m Tc / 201 Tl image acquisition in the 201 Tl energy window (77 ± 15% keV). GATE (Geant4 Application in Emission and Tomography) is employed due to its ability to simulate multiple radioactive sources concurrently. Two kinds of phantoms, including two digital and one physical phantom, are used. In the real and the simulation studies, data acquisition is carried out using eight energy windows. The ANN and the ANFIS are prepared in MATLAB, and the GATE results are used as a training data set. Three indications are evaluated and compared. The ANFIS method yields better outcomes for two indications (Spearman's rank correlation coefficient and contrast) and the two phantom results in each category. The maximum image biasing, which is the third indication, is found to be 6% more than that for the ANN.

  10. KEY COMPARISON: Activity measurements of the radionuclide 201Tl for the LNE-LNHB, France, PTB, Germany and the NPL, UK in the ongoing comparison BIPM.RI(II)-K1.Tl-201

    NASA Astrophysics Data System (ADS)

    Ratel, G.; Michotte, C.; Moune, M.; Bobin, C.; Kossert, K.; Johansson, L.

    2008-01-01

    In 2005, the Laboratoire national de métrologie et essais-Laboratoire national Henri Becquerel (LNE-LNHB) and the Physikalisch-Technische Bundesanstalt (PTB) each submitted a sample of known activity of 201Tl to the International Reference System (SIR). In 2006, the National Physical Laboratory (NPL) submitted their first sample. The range of values of the activity submitted was between 2 MBq and 63 MBq. These key comparison results have been included in the re-evaluated key comparison reference value and replaced the previous results for France and Germany in the matrix of degrees of equivalence in the key comparison database that now contains seven results, identifier BIPM.RI(II)-K1.Tl-201. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI Section II, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  11. Dynamic, equilibrium and human studies of adsorption of 201Tl by Prussian blue.

    PubMed

    Bhardwaj, Nidhi; Bhatnagar, Aseem; Pathak, D P; Singh, A K

    2006-03-01

    Prussian blue is the recommended but infrequently required antidote for radiocesium and thallium chemical poisoning. Conceivably, its most frequent application will be the decontamination of radiothallium (thallous chloride) from human body following myocardial scintigraphy. Dosage schedule and physicochemical parameters of interaction with radiothallium, however, need to be defined, as the known data is inadequate on this account. The objective of the present study is to create physiologically relevant and mathematically rigorous data on interaction of Prussian blue with Tl, to estimate dosage schedule of Prussian blue suitable for myocardial scintigraphy, and to perform preliminary human studies to evaluate the efficacy of the antidote in reducing the considerable radiation burden imparted by this radiotracer. Adsorption efficacy of Prussian blue for radiothallium was found to be more than 95% at basic (intestinal) pH even at low concentrations and in presence of the physiological cations, potassium and sodium. Isotherm analysis and derivations using Langmuir, Bajpai, Lagergreen, and Freundlich equations suggest a favorable adsorption of Tl on Prussian blue with qmax being 5,000 MBq g. Based on these findings and clinical considerations, particularly preferential gall bladder excretion and enterohepatic recycling of radioactive thallous chloride, a dose of 100 mg Prussian blue with every major meal for 3 days was considered adequate for the purpose. Our experience with the first two patients (serving as their own self-controls) suggests that Prussian blue therapy is a safe and effective method to significantly reduce radiation burden imparted by thallium myocardial scintigraphy.

  12. [Redistribution of 201 Tl after myocardial scintigraphy with dipyridamole: value in the detection of coronary stenosis and ventricular kinetic anomalies].

    PubMed

    Demangeat, J L; Wolff, F

    1985-12-01

    One hundred and eight-four patients suspected of having coronary artery disease underwent coronary and left ventricular angiography and Tl 201 myocardial scintigraphy with dipyridamole including images of redistribution after 3-4 hours. The results of scintigraphy were assessed visually in all cases and by quantitative analysis in 91 patients. Comparison of early (DIP) and late (REDIS) images showed three types of response: 1) no hypofixation on either (10 patients), 2) a constant defect (59 patients), 3) a reversible defect (115 patients, including 21 cases of "paradoxical" redistribution). The value of the redistribution images was assessed in the diagnosis of coronary stenosis and in the evaluation of ventricular wall function in post-stenotic zones. The following results were obtained: Visual analysis of the DIP scintigraphy alone gave 17 false positive and 8 false negative results (sens: 95%, spec: 41%). The false negative results were all observed in patients at high risk. The DIP/REDIS scintigraphy (considered normal if both images were normal) gave 20 false positive but only 1 false negative result (sens: 99%, spec: 32%). In addition, the negative predictivity increased from 60 to 90%. The considerable reduction in the number of false negative results was due to the detection of "paradoxical" redistribution. The finding indicates that late films must be taken systematically even if the early scintigraphy is normal. Quantitative analysis of DIP scintigraphy was less sensitive and more specific than visual analysis (sens: 82.7%, spec: 68.7%; NVP: 46%). The same was observed when the redistribution films were processed (DIP/REDIS): significantly increased sensitivity and negative predictive value at the cost of a lower specificity (sens: 96%, spec: 41%; NPV: 70%). No significant differences were observed between the type of scintigraphic defect (constant or reversible) and the probability of coronary stenosis (positive predictive value 93 and 86% respectively). "Paradoxical" redistribution corresponded to a pathological situation (PPV: 85%). A correlation was found between the reversible or permanent nature of the hypofixation and left ventricular function. Out of 142 segments showing reversible defects, 112 (79%) had normal or subnormal motion (moderate hypokinesia). Reversibility therefore usually indicated conservation of the viability of post-stenotic zones. Significant wall abnormalities were found in 62% of 140 segments with constant defects, mostly corresponding to infarction; however, in 38% there was no abnormality of wall motion or electrical changes of necrosis.(ABSTRACT TRUNCATED AT 400 WORDS)

  13. Single-photon agents for tumor imaging: 201Tl, 99mTc-MIBI, and 99mTc-tetrofosmin.

    PubMed

    Fukumoto, Mitsutaka

    2004-04-01

    This review aims at fostering comprehension and knowledge not only for expert physicians who can skillfully handle various techniques for tumor imaging but also for young practitioners in the field of nuclear medicine. As image processing software and hardware become smaller, faster and better, SPECT will adapt and incorporate these advances. A principal advantage of SPECT over PET is the more widespread availability of the equipment and lower cost for the introduction of the system in community-based facilities. Moreover, SPECT has become less dependent on a limited number of acknowledged experts for its interpretation owing to a variety of handy computer tools for imaging analyses. The increasing use of PET in tumor imaging is not necessarily proportional to the decline of SPECT. General physicians' attention to SPECT technology would also increase more by evoking their interest in "tracer imaging."

  14. DOS cones along atomic chains

    NASA Astrophysics Data System (ADS)

    Kwapiński, Tomasz

    2017-03-01

    The electron transport properties of a linear atomic chain are studied theoretically within the tight-binding Hamiltonian and the Green’s function method. Variations of the local density of states (DOS) along the chain are investigated. They are crucial in scanning tunnelling experiments and give important insight into the electron transport mechanism and charge distribution inside chains. It is found that depending on the chain parity the local DOS at the Fermi level can form cone-like structures (DOS cones) along the chain. The general condition for the local DOS oscillations is obtained and the linear behaviour of the local density function is confirmed analytically. DOS cones are characterized by a linear decay towards the chain which is in contrast to the propagation properties of charge density waves, end states and Friedel oscillations in one-dimensional systems. We find that DOS cones can appear due to non-resonant electron transport, the spin–orbit scattering or for chains fabricated on a substrate with localized electrons. It is also shown that for imperfect chains (e.g. with a reduced coupling strength between two neighboring sites) a diamond-like structure of the local DOS along the chain appears.

  15. Iterative deconvolution of simultaneous 99mTc and 201Tl projection data measured on a CdZnTe-based cardiac SPECT scanner

    NASA Astrophysics Data System (ADS)

    Kacperski, Krzysztof; Erlandsson, Kjell; Ben-Haim, Simona; Hutton, Brian F.

    2011-03-01

    We present a method of correcting self-scatter and crosstalk effects in simultaneous technetium-99m/thallium-201 stress/rest myocardial perfusion (single photon emission computed tomography) SPECT scans. The method, which is in essence a hybrid between the triple energy window method and scatter modelling, is based on a model of spatial and spectral distribution of projection counts in several selected energy windows. The parameters of the model are determined from measurements of thin rod sources in air when no in-object scatter or attenuation effects are present. The model equations are solved using the iterative maximum likelihood expectation maximization algorithm in the projection space to find estimates of the primary photopeak counts of both radionuclides. The method has been developed particularly for a novel dedicated cardiac camera based on CdZnTe pixellated detectors, although it can also be adapted to a conventional scintillator camera. The method has been validated in anthropomorphic phantom experiments. Significant improvement in defect contrast has been observed with only moderate increase in image noise. The application of the method to patient data is illustrated.

  16. A DOS Primer for Librarians.

    ERIC Educational Resources Information Center

    Beecher, Henry

    1989-01-01

    Presents a basic orientation to the functions and capabilities of disk operating systems (DOS), aimed at the nontechnically oriented user of IBM personal computers and compatible microcomputers. Areas discussed include booting up, the use of floppy and hard disks, file storage and manipulation, and directories. Further readings are provided. (CLB)

  17. A DOS Primer for Librarians.

    ERIC Educational Resources Information Center

    Beecher, Henry

    1989-01-01

    Presents a basic orientation to the functions and capabilities of disk operating systems (DOS), aimed at the nontechnically oriented user of IBM personal computers and compatible microcomputers. Areas discussed include booting up, the use of floppy and hard disks, file storage and manipulation, and directories. Further readings are provided. (CLB)

  18. Different Roles of DosS and DosT in the Hypoxic Adaptation of Mycobacteria▿

    PubMed Central

    Kim, Min-Ju; Park, Kwang-Jin; Ko, In-Jeong; Kim, Young Min; Oh, Jeong-Il

    2010-01-01

    The DosS (DevS) and DosT histidine kinases form a two-component system together with the DosR (DevR) response regulator in Mycobacterium tuberculosis. DosS and DosT, which have high sequence similarity to each other over the length of their amino acid sequences, contain two GAF domains (GAF-A and GAF-B) in their N-terminal sensory domains. Complementation tests in conjunction with phylogenetic analysis showed that DevS of Mycobacterium smegmatis is more closely related to DosT than DosS. We also demonstrated in vivo that DosS and DosT of M. tuberculosis play a differential role in hypoxic adaptation. DosT responds to a decrease in oxygen tension more sensitively and strongly than DosS, which might be attributable to their different autooxidation rates. The different responsiveness of DosS and DosT to hypoxia is due to the difference in their GAF-A domains accommodating the hemes. Multiple alignment analysis of the GAF-A domains of mycobacterial DosS (DosT) homologs and subsequent site-directed mutagenesis revealed that just one substitution of E87, D90, H97, L118, or T169 of DosS with the corresponding residue of DosT is sufficient to convert DosS to DosT with regard to the responsiveness to changes in oxygen tension. PMID:20675480

  19. DIGLIB. PC-DOS Graphics Subroutine Library

    SciTech Connect

    Burleson, R.R.

    1989-02-01

    DIGLIB is a collection of general graphics subroutines. It was designed to be small, reasonably fast, device-independent, and compatible with DEC-supplied operating systems for VAXes, PDP-11s, and LSI-11s, and the DOS operating system for IBM PCs and IBM-compatible machines. DIGLIB/PC runs on IBM PCs under PC-DOS or MS-DOS. The software is readily usable by casual programmers for two-dimensional plotting.

  20. Self-regulating the effortful "social dos".

    PubMed

    Cortes, Kassandra; Kammrath, Lara K; Scholer, Abigail A; Peetz, Johanna

    2014-03-01

    In the current research, we explored differences in the self-regulation of the personal dos (i.e., engaging in active and effortful behaviors that benefit the self) and in the self-regulation of the social dos (engaging in those same effortful behaviors to benefit someone else). In 6 studies, we examined whether the same trait self-control abilities that predict task persistence on personal dos would also predict task persistence on social dos. That is, would the same behavior, such as persisting through a tedious and attentionally demanding task, show different associations with trait self-control when it is framed as benefitting the self versus someone else? In Studies 1-3, we directly compared the personal and social dos and found that trait self-control predicted self-reported and behavioral personal dos but not social dos, even when the behaviors were identical and when the incentives were matched. Instead, trait agreeableness--a trait linked to successful self-regulation within the social domain--predicted the social dos. Trait self-control did not predict the social dos even when task difficulty increased (Study 4), but it did predict the social don'ts, consistent with past research (Studies 5-6). The current studies provide support for the importance of distinguishing different domains of self-regulated behaviors and suggest that social dos can be successfully performed through routes other than traditional self-control abilities. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  1. A DOS Primer for Librarians: Part II.

    ERIC Educational Resources Information Center

    Beecher, Henry

    1990-01-01

    Provides an introduction to DOS commands and strategies for the effective organization and use of hard disks. Functions discussed include the creation of directories and subdirectories, enhanced copying, the assignment of disk drives, and backing up the hard disk. (CLB)

  2. A DOS Primer for Librarians: Part II.

    ERIC Educational Resources Information Center

    Beecher, Henry

    1990-01-01

    Provides an introduction to DOS commands and strategies for the effective organization and use of hard disks. Functions discussed include the creation of directories and subdirectories, enhanced copying, the assignment of disk drives, and backing up the hard disk. (CLB)

  3. 27 CFR 9.175 - Dos Rios.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... is located in northern Mendocino County, California, at the confluence of the Eel River and the Middle Fork of the Eel River. The area's boundaries are defined as follows— (1) Beginning in the... the Middle Fork of the Eel River, to the southeast corner of section 11, T21N, R13W (Dos...

  4. "DOS for Managers." Management Training Series.

    ERIC Educational Resources Information Center

    Marion County Schools, Fairmont, WV.

    A plan is provided for a lesson on disk operating systems (DOS) for managers. Twenty-five lesson objectives are listed, followed by suggestions for learning activities and special resources. In the presentation section, key points and content are provided for 25 instructional topics that correspond to the 25 lesson objectives. The topics are as…

  5. DOS: the discrete-ordinates system. [LMFBR

    SciTech Connect

    Rhoades, W. A.; Emmett, M. B.

    1982-09-01

    The Discrete Ordinates System determines the flux of neutrons or photons due either to fixed sources specified by the user or to sources generated by particle interaction with the problem materials. It also determines numerous secondary results which depend upon flux. Criticality searches can be performed. Numerous input, output, and file manipulation facilities are provided. The DOS driver program reads the problem specification from an input file and calls various program modules into execution as specified by the input file.

  6. DIGLIB. PC-DOS Graphics Subroutine Library

    SciTech Connect

    Brand, H.R.

    1989-02-01

    DIGLIB is a collection of general graphics subroutines. It was designed to be small, reasonably fast, device-independent, and compatible with DEC-supplied operating systems for VAXes, PDP-11s, and LSI-11s, and the DOS operating system for IBM PCs and IBM-compatible machines. DIGLIB/VMS runs on the VAX and MicroVAX series of computers under VMS. The software is readily usable by casual programmers for two-dimensional plotting.

  7. Disk Operating System--DOS. Teacher Packet. Learning Activity Packets.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    The Learning Activity Packets (LAPs) contained in this manual are designed to assist the beginning user in understanding DOS (Disk Operating System). LAPs will not work with any version below DOS Version 3.0 and do not address the enhanced features of versions 4.0 or higher. These elementary activities cover only the DOS commands necessary to…

  8. Strains of the East Asian (W/Beijing) Lineage of Mycobacterium tuberculosis Are DosS/DosT-DosR Two-Component Regulatory System Natural Mutants▿ †

    PubMed Central

    Fallow, Ashley; Domenech, Pilar; Reed, Michael B.

    2010-01-01

    As part of our ongoing efforts to uncover the phenotypic consequences of genetic variability among clinical Mycobacterium tuberculosis isolates, we previously reported that isolates of the “East Asian” or “W/Beijing” lineage constitutively overexpress the coordinately regulated transcriptional program known as the DosR regulon under standard in vitro conditions. This phenotype distinguishes the W/Beijing lineage from all other M. tuberculosis lineages, which normally induce expression of this regulon only once exposed to low oxygen or nitric oxide, both of which result in inhibition of bacterial respiration and replication. Transcription of the DosR regulon is controlled through a two-component regulatory system comprising the transcription factor DosR and two possible cognate histidine sensor kinases, DosS and DosT. Through sequence analysis of a carefully selected set of isolates representing each of the major M. tuberculosis lineages, we describe herein a naturally occurring frameshift mutation in the gene encoding the DosT sensor kinase for isolates of the most recently evolved W/Beijing sublineages. Intriguingly, the occurrence of the frameshift mutation correlates precisely with the appearance of the constitutive DosR regulon phenotype displayed by the same “modern” W/Beijing strains. However, complementation studies have revealed that the mutation in dosT alone is not directly responsible for the constitutive DosR regulon phenotype. Our data serve to highlight the evolutionary pressure that exists among distinct M. tuberculosis lineages to maintain tight control over DosR regulon expression. PMID:20154135

  9. Inhibitors of Mycobacterium tuberculosis DosRST signaling and persistence.

    PubMed

    Zheng, Huiqing; Colvin, Christopher J; Johnson, Benjamin K; Kirchhoff, Paul D; Wilson, Michael; Jorgensen-Muga, Katriana; Larsen, Scott D; Abramovitch, Robert B

    2017-02-01

    The Mycobacterium tuberculosis (Mtb) DosRST two-component regulatory system promotes the survival of Mtb during non-replicating persistence (NRP). NRP bacteria help drive the long course of tuberculosis therapy; therefore, chemical inhibition of DosRST may inhibit the ability of Mtb to establish persistence and thus shorten treatment. Using a DosRST-dependent fluorescent Mtb reporter strain, a whole-cell phenotypic high-throughput screen of a ∼540,000 compound small-molecule library was conducted. The screen discovered novel inhibitors of the DosRST regulon, including three compounds that were subject to follow-up studies: artemisinin, HC102A and HC103A. Under hypoxia, all three compounds inhibit Mtb-persistence-associated physiological processes, including triacylglycerol synthesis, survival and antibiotic tolerance. Artemisinin functions by disabling the heme-based DosS and DosT sensor kinases by oxidizing ferrous heme and generating heme-artemisinin adducts. In contrast, HC103A inhibits DosS and DosT autophosphorylation activity without targeting the sensor kinase heme.

  10. CRONUS, A Distributed Operating System. Volume 4. CRONUS DOS implementation

    DTIC Science & Technology

    1988-06-01

    3 VI’(of i,:oa4r) TC- ’ CRON S, A DISTRIBUTED OPERATING S YS^4T EM: CRONUS DOS Implementation .131N Laboratories Incorporated R~. Schantz, K...Classification) CRONUS , A DISTRIBUTED OPERATING SYSTEM: CRONUS DOS Implementation 1Z.P ERSONAL AUTHOR(S) R. Schantz, K. Schroder, M. Barrow, G. Bono, M. Dean, R...second contract phase for development of the Cronus Project. ’% Cronus is the name given to the distributed operating system (DOS) and system

  11. Divorce Matters: Visitation Dos and Don'ts

    MedlinePlus

    divorce matters Visitation dos and don’ts For both parents and children, visitation is critical to maintaining ... sense of connectedness both during and after a divorce. But in the early stages of family restructuring ...

  12. Izabel dos Santos and the training of the health workers.

    PubMed

    Paiva, Carlos Henrique Assunção

    2015-06-01

    This article discusses the career of Izabel dos Santos (1927-2010) as a means of examining the connections between health schools and agendas in contemporary Brazil. The article highlights dos Santos's training and her work in the Serviço Especial de Saúde Pública (SESP- Special Public Health Service), the Pan American Health Organization (PAHO) and in the formulation and implementation of national training programs for human resources within the area of health from the late 1970s onwards. The article highlights dos Santos's central role in the formulation and implementation of training policies for health workers, especially nursing technicians and assistants, and demonstrates how she occupies an important place in the history of Brazilian public health.

  13. Isotopic and chemical investigations on Angra dos Reis

    NASA Technical Reports Server (NTRS)

    Wasserburg, G. J.; Tera, F.; Papanastassiou, D. A.; Huneke, J. C.

    1977-01-01

    Isotope ratios and chemical abundance measurements for a variety of elements are reported for total meteorite and mineral separates of the Angra dos Reis achondrite. U-Pb, Th-Pb, and Pb-Pb ages are concordant at 4.54 eons for the total meteorite and for high-purity whitlockite, which indicates that Angra dos Reis is an early planetary differentiate that has not been disturbed for these systems since 4.54 eons ago. The implications of different ratios of Sr-87 and Sr-86 found in different components are discussed. Xe isotopic measurements show that Pu-244 was enriched in the whitlockite relative to the pyroxene by a factor of about 18. Chemical enrichment factors between the whitlockite and the fassaitic pyroxene in Angra dos Reis are presented

  14. When worlds collide - Mac to MS-DOS. [Data transfer to and from Apple Macintosh computers and MS-DOS based personal computers

    SciTech Connect

    Busbey, A.B.

    1989-04-01

    A number of methods and products, both hardware and software, to allow data exchange between Apple Macintosh computers and MS-DOS based systems. These included serial null modem connections, MS-DOS hardware and/or software emulation, MS-DOS disk-reading hardware and networking.

  15. 48 CFR 619.402-70 - DOS designee.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Section 619.402-70 Federal Acquisition Regulations System DEPARTMENT OF STATE SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS Cooperation with the Small Business Administration 619.402-70 DOS designee. Where the FAR requires action by a Small Business Administration procurement center representative, but one has not been...

  16. Special Section--Library Workstations: Mac and DOS.

    ERIC Educational Resources Information Center

    Valauskas, Ed; Flower, Eric

    1993-01-01

    Two articles discuss the library hardware marketplace. The first examines the Apple Macintosh in libraries from 1984 to the present, including linking libraries, computers, and endusers over large geographic distances. The second article discusses upgrading components of systems in the IBM compatible, MS-DOS, and Windows environments as costs…

  17. Ultrafast ligand dynamics in the heme-based GAF sensor domains of the histidine kinases DosS and DosT from Mycobacterium tuberculosis†

    PubMed Central

    Vos, Marten H.; Bouzhir-Sima, Latifa; Lambry, Jean-Christophe; Luo, Hao; Eaton-Rye, Julian J.; Ioanoviciu, Alexandra; Ortiz de Montellano, Paul R.; Liebl, Ursula

    2011-01-01

    The transcriptional regulator DosR from M. tuberculosis plays a crucial role in the virulence to dormancy transition of the pathogen. DosR can be activated by DosT and DosS, two histidine kinases with heme-containing sensor GAF domains, capable of diatomic ligand binding, To investigate the initial processes occurring upon ligand dissociation, we performed ultrafast time-resolved absorption spectroscopy of the isolated sensor domains ligated with O2, NO and CO. The results reveal a relatively closed heme pocket for both proteins. For DosT the yield of O2 escape from the heme pocket on the picoseconds timescale upon photodissociation was found to be very low (1.5%), similar to other heme-based oxygen sensor proteins, implying that this sensor acts as an effective O2 trap. Remarkably, this yield is an order of magnitude higher in DosS (18%). For CO, by contrast, the fraction of CO rebinding within the heme pocket is higher in DosS. Experiments with mutant DosT sensor domains and molecular dynamics simulations indicate an important role in ligand discrimination of the distal tyrosine, present in both proteins, which forms a hydrogen bond with heme-bound O2. We conclude that despite their similarity, DosT and DosS display ligand-specific different primary dynamics during the initial phases of intra-protein signaling. The distal tyrosine, present in both proteins, plays an important role in these processes. PMID:22142262

  18. Deceiving entropy-based DoS detection

    NASA Astrophysics Data System (ADS)

    Özçelik, Ä.°lker; Brooks, Richard R.

    2014-06-01

    Denial of Service (DoS) attacks disable network services for legitimate users. A McAfee report shows that eight out of ten Critical Infrastructure Providers (CIPs) surveyed had a significant Distributed DoS (DDoS) attack in 2010.1 Researchers proposed many approaches for detecting these attacks in the past decade. Anomaly based DoS detection is the most common. In this approach, the detector uses statistical features; such as the entropy of incoming packet header fields like source IP addresses or protocol type. It calculates the observed statistical feature and triggers an alarm if an extreme deviation occurs. However, intrusion detection systems (IDS) using entropy based detection can be fooled by spoofing. An attacker can sniff the network to collect header field data of network packets coming from distributed nodes on the Internet and fuses them to calculate the entropy of normal background traffic. Then s/he can spoof attack packets to keep the entropy value in the expected range during the attack. In this study, we present a proof of concept entropy spoofing attack that deceives entropy based detection approaches. Our preliminary results show that spoofing attacks cause significant detection performance degradation.

  19. 33 CFR 105.245 - Declaration of Security (DoS).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... DoS and for handling DoS requests from a vessel. (b) At MARSEC Level 1, a facility receiving a cruise ship or a manned vessel carrying Certain Dangerous Cargo, in bulk, must comply with the following:...

  20. 33 CFR 105.245 - Declaration of Security (DoS).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... DoS and for handling DoS requests from a vessel. (b) At MARSEC Level 1, a facility receiving a cruise ship or a manned vessel carrying Certain Dangerous Cargo, in bulk, must comply with the following:...

  1. 33 CFR 105.245 - Declaration of Security (DoS).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... DoS and for handling DoS requests from a vessel. (b) At MARSEC Level 1, a facility receiving a cruise ship or a manned vessel carrying Certain Dangerous Cargo, in bulk, must comply with the following:...

  2. Structures of Mycobacterium tuberculosis DosR and DosR-DNA Complex Involved in Gene Activation during Adaptation to Hypoxic Latency

    SciTech Connect

    Wisedchaisri, Goragot; Wu, Meiting; Rice, Adrian E; Roberts, David M; Sherman, David R; Hol, Wim G.J.

    2010-07-20

    On encountering low oxygen conditions, DosR activates the transcription of 47 genes, promoting long-term survival of Mycobacterium tuberculosis in a non-replicating state. Here, we report the crystal structures of the DosR C-terminal domain and its complex with a consensus DNA sequence of the hypoxia-induced gene promoter. The DosR C-terminal domain contains four {alpha}-helices and forms tetramers consisting of two dimers with non-intersecting dyads. In the DNA-bound structure, each DosR C-terminal domain in a dimer places its DNA-binding helix deep into the major groove, causing two bends in the DNA. DosR makes numerous protein-DNA base contacts using only three amino acid residues per subunit: Lys179, Lys182, and Asn183. The DosR tetramer is unique among response regulators with known structures.

  3. Evaluation of the olfactory nerve transport function by SPECT-MRI fusion image with nasal thallium-201 administration.

    PubMed

    Shiga, Hideaki; Taki, Junichi; Yamada, Masato; Washiyama, Kohshin; Amano, Ryohei; Matsuura, Yukihiro; Matsui, Osamu; Tatsutomi, Shinji; Yagi, Sayaka; Tsuchida, Asuka; Yoshizaki, Tomokazu; Furukawa, Mitsuru; Kinuya, Seigo; Miwa, Takaki

    2011-12-01

    The aim of this study was to visualize the human olfactory transport pathway to the brain by performing imaging after nasal thallium-201 ((201)Tl) administration. Healthy volunteers were enrolled in this study after giving informed consent (five males, 35-51 years old). The subjects were nasally administered (201)TlCl into either the olfactory cleft. Twenty-four hours later, uptake of (201)Tl was detected by a single photon emission computed tomography (SPECT)/X-ray computed tomography hybrid system. For each subject, an MRI image was obtained and merged with the SPECT image. The peak of the (201)Tl uptake entered into the olfactory bulb in the anterior skull base through the cribriform lamina 24 h after nasal administration of (201)Tl. No participant had olfactory disturbance after treatment. Nasal (201)Tl administration was safely used to assess the direct pathway to the brain via the nose in healthy volunteers with normal olfactory threshold.

  4. Detection of DoS attacks using intrusion detection sensors

    NASA Astrophysics Data System (ADS)

    Ramakrishna, Pathmenanthan; Maarof, Mohd A.

    2002-09-01

    Intrusion detection systems have usually been developed using large host-based components. These components impose an extra load on the system where they run (sometimes even requiring a dedicated system) and are subject to tampering or disabling by an intruder. Additionally, intrusion detection systems have usually obtained information about host behavior through indirect means, such as audit trails or network packet traces. This potentially allows intruders to modify the information before the intrusion detection system obtains it and slows down the detection and prevention of DoS attacks, making it possible for an intruder to hide his activities. In this paper we propose work that will attempt to show that it is possible to perform intrusion detection mechanism of DoS attacks using small sensors embedded in a computer system. These sensors will look for signs of specific intrusions. They will perform target monitoring by observing the behavior of the through an audit trail or other indirect means in real time while the Snort IDS running. Furthermore, by being built into the computer system it could provide a flexible alert sensor which may not impose a considerable extra load on the host they monitor.

  5. Sedimentation survey of Lago Dos Bocas, Puerto Rico, June 1985

    USGS Publications Warehouse

    Quinones, Ferdinand; Melendez, Frank; Bonnet, Carlos

    1989-01-01

    A survey of the sedimentation of Dos Bocas reservoir, in central Puerto Rico, was conducted during July 1985. The survey showed that the capacity of the reservoir has declined from 30,420 acre-ft in 1942 to about 19,620 acre-ft. Sediment is accumulating in the reservoir at an average rate of about 251 acre-ft/yr, or about 0.83%/yr of the original capacity. The expected usable life of the reservoir on the basis of the long-term sedimentation rate is about 78 years. However, the sedimentation rate appears to have increased significantly since 1979. During the last six years, the average sedimentation rate has exceeded 600 acre-ft/yr. If this rate is maintained, the expected usable life of the reservoir would be about 32 years. (Author 's abstract)

  6. Document image archive transfer from DOS to UNIX

    NASA Technical Reports Server (NTRS)

    Hauser, Susan E.; Gill, Michael J.; Thoma, George R.

    1994-01-01

    An R&D division of the National Library of Medicine has developed a prototype system for automated document image delivery as an adjunct to the labor-intensive manual interlibrary loan service of the library. The document image archive is implemented by a PC controlled bank of optical disk drives which use 12 inch WORM platters containing bitmapped images of over 200,000 pages of medical journals. Following three years of routine operation which resulted in serving patrons with articles both by mail and fax, an effort is underway to relocate the storage environment from the DOS-based system to a UNIX-based jukebox whose magneto-optical erasable 5 1/4 inch platters hold the images. This paper describes the deficiencies of the current storage system, the design issues of modifying several modules in the system, the alternatives proposed and the tradeoffs involved.

  7. Microcystic meningioma with late-phase accumulation on thallium-201 single-photon emission computed tomography: case report.

    PubMed

    Matano, Fumihiro; Adachi, Koji; Murai, Yasuo; Kitamura, Takayuki; Ohashi, Ryuji; Teramoto, Akira; Morita, Akio

    2014-01-01

    Microcystic meningiomas are rare but benign brain tumors. Previous reports have shown that Thallium-201 single-photon emission computed tomography ((201)Tl SPECT) demonstrated a higher late-phase accumulation of (201)Tl in malignant or recurrent meningiomas than in nonaggressive meningiomas. No study has reported (201)Tl SPECT findings in microcystic meningiomas. We here describe a case of a microcystic meningioma with a high (201)Tl SPECT retention rate in a 62-year-old woman who complained of headache. Computed tomography revealed an intracranial tumor in the right frontal lobe. Moreover, (201)Tl SPECT revealed a high uptake of (201)Tl in the tumor, which was particularly prominent in the delayed phase. The uptake index on an early image was 1.46 and that on a delayed image was 1.35. Therefore, the retention index was 0.92. After 2 years of tumor growth, we performed successful radical resection, and histological examination revealed the presence of a microcystic meningioma. Therefore, we concluded that (201)Tl SPECT may be useful for the preoperative diagnosis of microcystic meningiomas and that late-phase accumulation of (201)Tl is not a specific finding of malignant brain tumors. Therefore, we need to be careful in the evaluation and judgment of high retention in a delayed image of (201)Tl SPECT.

  8. Mycobacterium tuberculosis growth following aerobic expression of the DosR regulon.

    PubMed

    Minch, Kyle; Rustad, Tige; Sherman, David R

    2012-01-01

    The Mycobacterium tuberculosis regulator DosR is induced by multiple stimuli including hypoxia, nitric oxide and redox stress. Overlap of these stimuli with conditions thought to promote latency in infected patients fuels a model in which DosR regulon expression is correlated with bacteriostasis in vitro and a proxy for latency in vivo. Here, we find that inducing the DosR regulon to wildtype levels in aerobic, replicating M. tuberculosis does not alter bacterial growth kinetics. We conclude that DosR regulon expression alone is insufficient for bacterial latency, but rather is expressed during a range of growth states in a dynamic environment.

  9. DosS Is required for the complete virulence of mycobacterium tuberculosis in mice with classical granulomatous lesions.

    PubMed

    Gautam, Uma S; McGillivray, Amanda; Mehra, Smriti; Didier, Peter J; Midkiff, Cecily C; Kissee, Ryan S; Golden, Nadia A; Alvarez, Xavier; Niu, Tianhua; Rengarajan, Jyothi; Sherman, David R; Kaushal, Deepak

    2015-06-01

    Mycobacterium tuberculosis (Mtb) must counter hypoxia within granulomas to persist. DosR, in concert with sensor kinases DosS and DosT, regulates the response to hypoxia. Yet Mtb lacking functional DosR colonize the lungs of C57Bl/6 mice, presumably owing to the lack of organized lesions with sufficient hypoxia in that model. We compared the phenotype of the Δ-dosR, Δ-dosS, and Δ-dosT mutants to Mtb using C3HeB/FeJ mice, an alternate mouse model where lesions develop hypoxia. C3HeB/FeJ mice were infected via aerosol. The progression of infection was analyzed by tissue bacterial burden and histopathology. A measure of the comparative global immune responses was also analyzed. Although Δ-dosR and Δ-dosT grew comparably to wild-type Mtb, Δ-dosS exhibited a significant defect in bacterial burden and pathology in vivo, accompanied by ablated proinflammatory response. Δ-dosS retained the ability to induce DosR. The Δ-dosS mutant was also attenuated in murine macrophages ex vivo, with evidence of reduced expression of the proinflammatory signature. Our results show that DosS, but not DosR and DosT, is required by Mtb to survive in C3HeB/FeJ mice. The attenuation of Δ-dosS is not due to its inability to induce the DosR regulon, nor is it a result of the accumulation of hypoxia. That the in vivo growth restriction of Δ-dosS could be mimicked ex vivo suggested sensitivity to macrophage oxidative burst. Anoxic caseous centers within tuberculosis lesions eventually progress to cavities. Our results provide greater insight into the molecular mechanisms of Mtb persistence within host lungs.

  10. America Inc.: John Dos Passos'"USA" as Professional Writing Textbook.

    ERIC Educational Resources Information Center

    Di Renzo, Anthony

    While working as a special consultant for General Mills in 1948, John Dos Passos wrote a report explaining the latest scientific research and technological advancements and how the postwar economy was affecting General Mills and the cereal market. General Mills, using a real writer for a corporate freelance, profited from Dos Passos' expertise and…

  11. Myocardial metabolic, hemodynamic, and electrocardiographic significance of reversible thallium-201 abnormalities in hypertrophic cardiomyopathy

    SciTech Connect

    Cannon, R.O. 3d.; Dilsizian, V.; O'Gara, P.T.; Udelson, J.E.; Schenke, W.H.; Quyyumi, A.; Fananapazir, L.; Bonow, R.O. )

    1991-05-01

    Exercise-induced abnormalities during thallium-201 scintigraphy that normalize at rest frequently occur in patients with hypertrophic cardiomyopathy. However, it is not known whether these abnormalities are indicative of myocardial ischemia. Fifty patients with hypertrophic cardiomyopathy underwent exercise {sup 201}Tl scintigraphy and, during the same week, measurement of myocardial lactate metabolism and hemodynamics during pacing stress. Thirty-seven patients (74%) had one or more {sup 201}Tl abnormalities that completely normalized after 3 hours of rest; 26 had regional myocardial {sup 201}Tl defects, and 26 had apparent left ventricular cavity dilatation with exercise, with 15 having coexistence of these abnormal findings. Of the 37 patients with reversible {sup 201}Tl abnormalities, 27 (73%) had metabolic evidence of myocardial ischemia during rapid atrial pacing compared with four of 13 patients (31%) with normal {sup 201}Tl scans (p less than 0.01). Eleven patients had apparent cavity dilatation as their only {sup 201}Tl abnormality; their mean postpacing left ventricular end-diastolic pressure was significantly higher than that of the 13 patients with normal {sup 201}Tl studies (33 +/- 5 versus 21 +/- 10 mm Hg, p less than 0.001). There was no correlation between the angiographic presence of systolic septal or epicardial coronary arterial compression and the presence or distribution of {sup 201}Tl abnormalities. Patients with ischemic ST segment responses to exercise had an 80% prevalence rate of reversible {sup 201}Tl abnormalities and a 70% prevalence rate of pacing-induced ischemia. However, 69% of patients with nonischemic ST segment responses had reversible {sup 201}Tl abnormalities, and 55% had pacing-induced ischemia. Reversible {sup 201}Tl abnormalities during exercise stress are markers of myocardial ischemia in hypertrophic cardiomyopathy and most likely identify relatively underperfused myocardium.

  12. Unique Regulation of the DosR Regulon in the Beijing Lineage of Mycobacterium tuberculosis.

    PubMed

    Domenech, Pilar; Zou, Jason; Averback, Alexandra; Syed, Nishath; Curtis, Daniele; Donato, Samuel; Reed, Michael B

    2017-01-15

    The DosR regulon, a set of 48 genes normally expressed in Mycobacterium tuberculosis under conditions that inhibit aerobic respiration, is controlled via the DosR-DosS/DosT two-component system. While the regulon requires induction in most M. tuberculosis isolates, for members of the Beijing lineage, its expression is uncoupled from the need for signaling. In our attempts to understand the mechanistic basis for this uncoupling in the Beijing background, we previously reported the identification of two synonymous single-nucleotide polymorphisms (SNPs) within the adjacent Rv3134c gene. In the present study, we have interrogated the impact of these SNPs on dosR expression in wild-type strains, as well as a range of dosR-dosS-dosT mutants, for both Beijing and non-Beijing M. tuberculosis backgrounds. In this manner, we have unequivocally determined that the C601T dosR promoter SNP is the sole requirement for the dramatic shift in the pattern of DosR regulon expression seen in this globally important lineage. Interestingly, we also show that DosT is completely nonfunctional within these strains. Thus, a complex series of evolutionary steps has led to the present-day Beijing DosR phenotype that, in turn, potentially confers a fitness advantage in the face of some form of host-associated selective pressure. Mycobacterium tuberculosis strains of the Beijing lineage have been described as being of enhanced virulence compared to other lineages, and in certain regions, they are associated with the dramatic spread of multidrug-resistant tuberculosis (TB). In terms of trying to understand the functional basis for these broad epidemiological phenomena, it is interesting that, in contrast to the other major lineages, the Beijing strains all constitutively overexpress members of the DosR regulon. Here, we identify the mutational events that led to the evolution of this unique phenotype. In addition, our work highlights the fact that important phenotypic differences exist between

  13. The DosR regulon of M. tuberculosis and antibacterial tolerance

    PubMed Central

    Bartek, I.L.; Rutherford, R.; Gruppo, V.; Morton, R.A.; Morris, R.P.; Klein, M.R.; Visconti, K.C.; Ryan, G.J.; Schoolnik, G.K.; Lenaerts, A.; Voskuil, M.I.

    2009-01-01

    Summary Adaptation of Mycobacterium tuberculosis to an anaerobic dormant state that is tolerant to several antibacterials is mediated largely by a set of highly expressed genes controlled by DosR. A DosR mutant was constructed to investigate whether the DosR regulon is involved in antibacterial tolerance. We demonstrate that induction of the regulon is not required for drug tolerance either in vivo during a mouse infection or in vitro during anaerobic dormancy. Thus, drug tolerance observed in these models is due to other mechanisms such as the bacilli simply being in a non-replicating or low metabolic state. Our data also demonstrate that the DosR regulon is not essential for virulence during chronic murine infection. However, decreased lung pathology was observed in the DosR mutant. We also show that the DosR regulon genes are more highly conserved in environmental mycobacteria, than in pathogenic mycobacteria lacking a latent phase or environmental reservoir. It is possible that the DosR regulon could contribute to drug tolerance in human infections; however, it is not the only mechanism and not the primary mechanism for tolerance during a mouse infection. These data suggest that the regulon evolved not for pathogenesis or drug tolerance but for adaptation to anaerobic conditions in the environment and has been adapted by M. tuberculosis for survival during latent infection. PMID:19577518

  14. The Rio dos Sinos watershed: an economic and social space and its interface with environmental status.

    PubMed

    Figueiredo, J A S; Drumm, E; Rodrigues, M A S; Spilki, F R

    2010-12-01

    The Rio dos Sinos watershed is located in the eastern region of the state of Rio Grande do Sul and includes 32 municipalities. These municipalities develop several different economic activities such as farming and livestock along the 190 km length of the Rio dos Sinos, one of the rivers with the worst quality of water in Brazil. The region is also characterised by growing urbanisation and heavy industrialisation. The main economic activity is the leather and footwear industry. This diversified land use puts the Rio dos Sinos watershed at risk of a wide range of potential environmental impacts. The aim of the present article is to discuss the socioeconomic process currently implemented in the Rio dos Sinos watershed and the effect of these human actions on the environmental quality described throughout this special issue of the Brazilian Journal of Biology.

  15. DosR-regulon genes induction in Mycobacterium bovis BCG under aerobic conditions.

    PubMed

    Flores Valdez, Mario Alberto; Schoolnik, Gary K

    2010-05-01

    In this report we demonstrated that under aerobic conditions, Mycobacterium bovis BCG expressing an hsp60-driven second copy of the hypoxia-related transcriptional regulator DosR increased 2-fold or greater the expression of 38 out of the 48 genes belonging to the DosR regulon, including the latency antigens Rv1733c, Rv2029, Rv2627, and Rv2628. Expression of DosR under these conditions slightly delayed in vitro growth, but did not promote a non-replicating state as opposed to microaerobic and hypoxic adaptation. Our results suggest BCG producing DosR can be cultured under standard in vitro conditions, allowing evaluation of this strain as a latency-specific vaccine candidate.

  16. Prevalence and clinical significance of painless ST segment depression during early postinfarction exercise testing

    SciTech Connect

    Gibson, R.S.; Beller, G.A.; Kaiser, D.L.

    1987-03-01

    In a recent study of 190 survivors of acute myocardial infarction, the authors sought to determine whether exercise-induced painless ST segments depression indicates residual myocardial ischemia, as defined by /sup 201/Tl scintigraphic criteria. 2 weeks after uncomplicated myocardial infarction, and whether quantitative /sup 201/Tl imaging enhances the prognostic value of such an exercise electrocardiographic response.

  17. Retention index of thallium-201 single photon emission computerised tomography (SPECT) as an indicator of metastasis in adenocarcinoma of the lung.

    PubMed Central

    Takekawa, H.; Itoh, K.; Abe, S.; Ogura, S.; Isobe, H.; Sukou, N.; Furudate, M.; Kawakami, Y.

    1994-01-01

    We examined the relationship between the retention of thallium-201 (201Tl) on a delayed scan and the metastatic potential of adenocarcinomas of the lung. We studied 43 patients with adenocarcinoma of the lung and divided them into two groups according to the presence or absence of lymph node metastasis. 201Tl single photon emission computerised tomography (SPECT) was conducted twice: 15 min (early scan) and 120 min (delayed scan) after intravenous injection of 3 mCi of 201Tl chloride. We calculated the retention index in order to evaluate the degree of 201Tl retention in the primary tumour. The retention indices were significantly higher in the group that was positive for lymph node metastasis than in the negative group. In adenocarcinomas with high metastatic potential, 201Tl SPECT demonstrated slow washout or increased retention on the delayed scan. The retention index of 201Tl SPECT is a useful indicator of metastatic potential, thereby facilitating the prediction of prognosis, and provides insight into the relationship between 201Tl uptake and malignancy. This is the first report demonstrating a significant relationship between the retention of 201Tl SPECT and lymph node metastasis. Images Figure 1 PMID:8054281

  18. Dipyridamole thallium-201 myocardial scintigraphy

    SciTech Connect

    Not Available

    1988-09-01

    Thallium-201 (/sup 201/Tl) myocardial scintigraphy is a sensitive technique for detecting coronary artery disease. Standardized exercise testing is the most common method for inducing myocardial stress for /sup 201/Tl imaging. Unfortunately, a significant number of patients are unable to undergo adequate treadmill or bicycle exercise. In these patients, pharmacologic stress with dipyridamole provides a safe, efficacious, and reliable alternative.

  19. Linking Social Media Reports to Network Indicators of DoS Attacks

    DTIC Science & Technology

    2015-02-15

    reporting in fast-paced social media such as Twitter, but these reports are rarely linked to quantiable network behavior. A data set of network-based...FEB 2015 2. REPORT TYPE N/A 3. DATES COVERED 4. TITLE AND SUBTITLE Linking Social Media Reports to Network Indicators of DoS Attacks 5a...Random sample of 30 (D, E) pairs yielding 21 unique entities (E) Linking Social Media Reports to Network Indicators of DoS Attacks Evan Wright

  20. Measurements of degree of sensitization (DoS) in aluminum alloys using EMAT ultrasound.

    PubMed

    Li, Fang; Xiang, Dan; Qin, Yexian; Pond, Robert B; Slusarski, Kyle

    2011-07-01

    Sensitization in 5XXX aluminum alloys is an insidious problem characterized by the gradual formation and growth of beta phase (Mg(2)Al(3)) at grain boundaries, which increases the susceptibility of alloys to intergranular corrosion (IGC) and intergranular stress-corrosion cracking (IGSCC). The degree of sensitization (DoS) is currently quantified by the ASTM G67 Nitric Acid Mass Loss Test, which is destructive and time consuming. A fast, reliable, and non-destructive method for rapid detection and the assessment of the condition of DoS in AA5XXX aluminum alloys in the field is highly desirable. In this paper, we describe a non-destructive method for measurements of DoS in aluminum alloys with an electromagnetic acoustic transducer (EMAT). AA5083 aluminum alloy samples were sensitized at 100°C with processing times varying from 7days to 30days. The DoS of sensitized samples was first quantified with the ASTM 67 test in the laboratory. Both ultrasonic velocity and attenuation in sensitized specimens were then measured using EMAT and the results were correlated with the DoS data. We found that the longitudinal wave velocity was almost a constant, independent of the sensitization, which suggests that the longitudinal wave can be used to determine the sample thickness. The shear wave velocity and especially the shear wave attenuation are sensitive to DoS. Relationships between DoS and the shear velocity, as well as the shear attenuation have been established. Finally, we performed the data mining to evaluate and improve the accuracy in the measurements of DoS in aluminum alloys with EMAT. Copyright © 2010 Elsevier B.V. All rights reserved.

  1. DataPlus™ - a revolutionary applications generator for DOS hand-held computers

    Treesearch

    David Dean; Linda Dean

    2000-01-01

    DataPlus allows the user to easily design data collection templates for DOS-based hand-held computers that mimic clipboard data sheets. The user designs and tests the application on the desktop PC and then transfers it to a DOS field computer. Other features include: error checking, missing data checks, and sensor input from RS-232 devices such as bar code wands,...

  2. Dos, a heme-binding PAS protein from Escherichia coli, is a direct oxygen sensor.

    PubMed

    Delgado-Nixon, V M; Gonzalez, G; Gilles-Gonzalez, M A

    2000-03-14

    A direct sensor of O(2), the Dos protein, has been found in Escherichia coli. Previously, the only biological sensors known to respond to O(2) by direct and reversible binding were the FixL proteins of Rhizobia. A heme-binding region in Dos is 60% homologous to the O(2)-sensing PAS domain of the FixL protein, but the remainder of Dos does not resemble FixL. Specifically, the C-terminal domain of Dos, presumed to be a regulatory partner that couples to its heme-binding domain, is not a histidine kinase but more closely resembles a phosphodiesterase. The absorption spectra of Dos indicate that both axial positions of the heme iron are coordinated to side chains of the protein. Nevertheless, O(2) and CO bind to Dos with K(d) values of 13 and 10 microM, respectively, indicating a strong discrimination against CO binding. Association rate constants for binding of O(2) (3 mM(-)(1) s(-)(1)), CO (1 mM(-)(1) s(-)(1)) and even NO (2 mM(-)(1) s(-)(1)) are extraordinarily low and very similar. Displacement of an endogenous ligand, probably Met 95, from the heme iron in Dos triggers a conformational change that alters the activity of the enzymatic domain. This sensing mechanism differs from that of FixL but resembles that of the CO sensor CooA of Rhodospirillum rubrum. Overall the results provide evidence for a heme-binding subgroup of PAS-domain proteins whose working range, signaling mechanisms, and regulatory partners can vary considerably.

  3. Non-invasive tissue temperature measurements based on quantitative diffuse optical spectroscopy (DOS) of water.

    PubMed

    Chung, S H; Cerussi, A E; Merritt, S I; Ruth, J; Tromberg, B J

    2010-07-07

    We describe the development of a non-invasive method for quantitative tissue temperature measurements using Broadband diffuse optical spectroscopy (DOS). Our approach is based on well-characterized opposing shifts in near-infrared (NIR) water absorption spectra that appear with temperature and macromolecular binding state. Unlike conventional reflectance methods, DOS is used to generate scattering-corrected tissue water absorption spectra. This allows us to separate the macromolecular bound water contribution from the thermally induced spectral shift using the temperature isosbestic point at 996 nm. The method was validated in intralipid tissue phantoms by correlating DOS with thermistor measurements (R=0.96) with a difference of 1.1+/-0.91 degrees C over a range of 28-48 degrees C. Once validated, thermal and hemodynamic (i.e. oxy- and deoxy-hemoglobin concentration) changes were measured simultaneously and continuously in human subjects (forearm) during mild cold stress. DOS-measured arm temperatures were consistent with previously reported invasive deep tissue temperature studies. These results suggest that DOS can be used for non-invasive, co-registered measurements of absolute temperature and hemoglobin parameters in thick tissues, a potentially important approach for optimizing thermal diagnostics and therapeutics.

  4. Non-invasive tissue temperature measurements based on quantitative diffuse optical spectroscopy (DOS) of water

    PubMed Central

    Chung, SH; Cerussi, AE; Merritt, SI; Ruth, J; Tromberg, BJ

    2012-01-01

    We describe the development of a non-invasive method for quantitative tissue temperature measurements using Broadband diffuse optical spectroscopy (DOS). Our approach is based on well-characterized opposing shifts in near-infrared (NIR) water absorption spectra that appear with temperature and macromolecular binding state. Unlike conventional reflectance methods, DOS is used to generate scattering-corrected tissue water absorption spectra. This allows us to separate the macromolecular bound water contribution from the thermally induced spectral shift using the temperature isosbestic point at 996 nm. The method was validated in intralipid tissue phantoms by correlating DOS with thermistor measurements (R = 0.96) with a difference of 1.1 ± 0.91 °C over a range of 28–48 °C. Once validated, thermal and hemodynamic (i.e. oxy- and deoxy-hemoglobin concentration) changes were measured simultaneously and continuously in human subjects (forearm) during mild cold stress. DOS-measured arm temperatures were consistent with previously reported invasive deep tissue temperature studies. These results suggest that DOS can be used for non-invasive, co-registered measurements of absolute temperature and hemoglobin parameters in thick tissues, a potentially important approach for optimizing thermal diagnostics and therapeutics. PMID:20551502

  5. Documenting 35 years of land cover change: Lago Cachet Dos drainage, Chile

    USGS Publications Warehouse

    Friesen, Beverly A.; Nimick, David A.; Mcgrath, Daniel; Cole, Christopher J.; Wilson, Earl M.; Noble, Suzanne M.; Fahey, Mark J.; Leidich, Jonathan; O'Kuinghttons Villena, Jorge I.

    2015-01-01

    The U.S. Geological Survey (USGS) Special Applications Science Center is monitoring temporal changes at the Colonia Glacier and Lago Cachet Dos, Northern Patagonia Icefield of southern Chile. This location is one of the newest international sites in the USGS Global Fiducial Program (GFP)—a program which provides systematic monitoring of dynamic and environmentally critical areas with high-resolution imagery (http://gfp.usgs.gov/). In 2008, Lago Cachet Dos began experiencing glacial lake outburst floods (GLOFs) during which the entire pool of water (about 200 million cubic meters) rapidly drains from the lake and flows south-southeast through the Colonia Glacier. These catastrophic events cause massive erosion of valley-fill deposits and consequent upstream expansion of Lago Cachet Dos towards Lago Cachet Uno.  Panchromatic and multispectral images for 1979, 2007, and 2014 highlight the dramatic changes that have occurred at this site over a 35-year period. The lake was smallest in 1979, when the Colonia Glacier was at its maximum extent during the study period. Between 1979 and 2007, the glacier shrank causing an increase in the surface area of the lake. The size of the lake increased substantially, from 2.98 square kilometers (km2) in 1979 to 4.41 km2 in 2014, primarily due to erosion of valley-fill deposits upstream of its northern edge by the 15 GLOFs that occurred between April 2008 and February 2014. Ongoing studies of the Colonia Glacier and Lago Cachet Dos are focused on providing real-time monitoring of Lago Cachet Dos lake levels, understanding the history of advances and retreats of the Colonia Glacier, and determining the physical mechanisms and hazards associated with the GLOFs that come from Lago Cachet Dos.

  6. WE-E-BRB-10: DosCheck - an Electronic Chart Checking Tool for Dosimetrists.

    PubMed

    Yang, D; Wu, Y; Yaddanapudi, S; Moore, K; Pierbuxg, B; Brame, S; Mutic, S

    2012-06-01

    In addition to treatment planning, dosimetrists have to prepare documentation and manually enter data in treatment management system (TMS) which did not transfer or setup automatically. The required documents and data are dependent on the disease site, treatment machine and clinical workflow. Errors and inconsistencies can cause redundant work, treatment delays and potentially treatment errors. To address these issues, an electronic checking software tool, DosCheck was clinically implemented to check the existence of necessary documentations and the integrity of manually-entered data. The purpose of this software is to reduce the frequency of human errors and to improve efficiency. DosCheck reads data and documents from 1) TMS, 2) Pinnacle TPS, and 3) DICOM plan files stored in a DICOM-RT PACS. It processes documents in Word and PDF format, treatment plan data in Pinnacle native format and DICOM format, and Mosaiq data in database records. The software cross-checks data accuracy and consistency by following rules that are pre-defined according to the clinical requirements and treatment sties. It interacts with dosimetrists and presents instantaneous results via graphical user interface. DosCheck has been implemented in C#. It performs a full check for a patient with 20 seconds. It has been clinically commissioned and is used daily by all dosimetrists at our institution. Retrospective analysis shows that DosCheck identifies 30% to 40% of previously reported dosimetrist human errors. Additional ∼30% errors are checked by other tools that could be integrated DosCheck in the near future. As an electronic data checking tool, DosCheck can obtain and process data and documents from multiple clinical computer systems in the radiation oncology department, and perform checks according to clinical rules. It is able to improve the accuracy and efficiency of clinical data and document process, and therefore to reduce any potential inconsistencies and errors. © 2012 American

  7. Reagent based DOS: a "Click, Click, Cyclize" strategy to probe chemical space.

    PubMed

    Rolfe, Alan; Lushington, Gerald H; Hanson, Paul R

    2010-05-07

    The synthesis of small organic molecules as probes for discovering new therapeutic agents has been an important aspect of chemical-biology. Herein we report a reagent-based, diversity-oriented synthetic (DOS) strategy to probe chemical and biological space via a "Click, Click, Cyclize" protocol. In this DOS approach, three sulfonamide linchpins underwent cyclization protocols with a variety of reagents to yield a collection of structurally diverse S-heterocycles. In silico analysis is utilized to evaluate the diversity of the compound collection against chemical space (PC analysis), shape space (PMI) and polar surface area (PSA) calculations.

  8. Sedimentation survey of Lago Dos Bocas, Utuado, Puerto Rico, January 2010

    USGS Publications Warehouse

    Soler-López, Luis R.

    2014-01-01

    Lago Dos Bocas reservoir was completed in 1942 to provide water for hydroelectric power generation along the northern coast of Puerto Rico. The reservoir had an original storage capacity of 37.50 million cubic meters (Mm3). The dam is located about 9 kilometers (km) northeast of the town of Utuado, immediately downstream of the original confluence of the Río Grande de Arecibo and the Río Caonillas (fig. 1). The Puerto Rico Electric Power Authority (PREPA) owns and operates the Lago Dos Bocas reservoir, and since 1996, the reservoir has become an essential part of the Puerto Rico Aqueduct and Sewer Authority (PRASA) North Coast Superaqueduct Project. The Superaqueduct is supplied by controlled releases for hydroelectric power generation that replenish the public-supply raw-water intake pool located about 10 km downstream from the Lago Dos Bocas Dam (fig. 1). As of 2005, the Superaqueduct supplies about 4.03 cubic meters per second (m3/s) (348,192 cubic meters per day [m3/d]) of potable water to communities along the northern coast, from Arecibo to the San Juan metropolitan area. Because of the importance of the reservoir to the North Coast Superaqueduct, the U.S. Geological Survey (USGS), in cooperation with PRASA, conducted a sedimentation survey of Lago Dos Bocas in January 2009. The results of this survey were used to estimate the useful life and the firm yield of the reservoir, and evaluate the need to dredge the reservoir.

  9. Content Analysis Schedule for Bilingual Education Programs: Programa en Dos Lenguas.

    ERIC Educational Resources Information Center

    Ludanyi, R. P.; Shore, Marietta Saravia

    This content analysis schedule for the "Programa en Dos Lenguas" of Fort Worth, Texas, presents information on the history, funding, and scope of the project. Included are sociolinguistic process variables such as the native and dominant languages of students and their interaction. Information is provided on staff selection and the…

  10. Function, regulation and pathological roles of the Gab/DOS docking proteins

    PubMed Central

    2009-01-01

    Since their discovery a little more than a decade ago, the docking proteins of the Gab/DOS family have emerged as important signalling elements in metazoans. Gab/DOS proteins integrate and amplify signals from a wide variety of sources including growth factor, cytokine and antigen receptors as well as cell adhesion molecules. They also contribute to signal diversification by channelling the information from activated receptors into signalling pathways with distinct biological functions. Recent approaches in protein biochemistry and systems biology have revealed that Gab proteins are subject to complex regulation by feed-forward and feedback phosphorylation events as well as protein-protein interactions. Thus, Gab/DOS docking proteins are at the centre of entire signalling subsystems and fulfil an important if not essential role in many physiological processes. Furthermore, aberrant signalling by Gab proteins has been increasingly linked to human diseases from various forms of neoplasia to Alzheimer's disease. In this review, we provide a detailed overview of the structure, effector functions, regulation and evolution of the Gab/DOS family. We also summarize recent findings implicating Gab proteins, in particular the Gab2 isoform, in leukaemia, solid tumours and other human diseases. PMID:19737390

  11. Pygmy Rice Rat as Potential Host of Castelo dos Sonhos Hantavirus

    PubMed Central

    Travassos da Rosa, Elizabeth S.; Medeiros, Daniele B. A.; Nunes, Márcio R.T.; Simith, Darlene B.; Pereira, Armando de Souza; Elkhoury, Mauro R.; Lavocat, Marília; Marques, Aparecido A.R.; Via, Alba Valéria; D’Andrea, Paulo; Bonvicino, Cibele R.; Lemos, Elba Regina S.

    2011-01-01

    To study the dynamics of wild rodent populations and identify potential hosts for hantavirus, we conducted an eco-epidemiologic study in Campo Novo do Parecis, Mato Grosso State, Brazil. We detected and genetically characterized Castelo dos Sonhos virus found in a species of pygmy rice rat (Oligoryzomys utiaritensis). PMID:21801642

  12. 33 CFR 106.250 - Declaration of Security (DoS).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Declaration of Security (DoS). 106.250 Section 106.250 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MARITIME SECURITY MARINE SECURITY: OUTER CONTINENTAL SHELF (OCS) FACILITIES Outer Continental Shelf...

  13. 33 CFR 106.250 - Declaration of Security (DoS).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Declaration of Security (DoS). 106.250 Section 106.250 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MARITIME SECURITY MARINE SECURITY: OUTER CONTINENTAL SHELF (OCS) FACILITIES Outer Continental Shelf...

  14. 33 CFR 106.250 - Declaration of Security (DoS).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Declaration of Security (DoS). 106.250 Section 106.250 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MARITIME SECURITY MARINE SECURITY: OUTER CONTINENTAL SHELF (OCS) FACILITIES Outer Continental Shelf...

  15. 33 CFR 106.250 - Declaration of Security (DoS).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Declaration of Security (DoS). 106.250 Section 106.250 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MARITIME SECURITY MARINE SECURITY: OUTER CONTINENTAL SHELF (OCS) FACILITIES Outer Continental Shelf...

  16. 33 CFR 106.250 - Declaration of Security (DoS).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Declaration of Security (DoS). 106.250 Section 106.250 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MARITIME SECURITY MARINE SECURITY: OUTER CONTINENTAL SHELF (OCS) FACILITIES Outer Continental Shelf...

  17. 33 CFR 105.245 - Declaration of Security (DoS).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) of this section. (e) At MARSEC Levels 1 and 2, FSOs of facilities that frequently interface with the... part to implement a DoS with the VSO prior to any vessel-to-facility interface when he or she deems it...

  18. 33 CFR 105.245 - Declaration of Security (DoS).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) of this section. (e) At MARSEC Levels 1 and 2, FSOs of facilities that frequently interface with the... part to implement a DoS with the VSO prior to any vessel-to-facility interface when he or she deems it...

  19. Stretching the Software Dollar: MS-DOS Shareware and Public Domain Software.

    ERIC Educational Resources Information Center

    Grosch, Audrey N.

    1989-01-01

    Discusses shareware and public domain software for MS-DOS systems that are available through bulletin board systems (BBS). Problems with computer viruses are discussed; shareware available for communications, database and file management, spreadsheets, word processing, and menuing software is described; and source information for software is…

  20. Entre Dos Mundos/Between Two Worlds: Youth Violence Prevention for Acculturating Latino Families

    ERIC Educational Resources Information Center

    Smokowski, Paul R.; Bacallao, Martica

    2009-01-01

    Objective: This study evaluated the efficacy of Entre Dos Mundos/Between Two Worlds (EDM) prevention for Latino adolescents. Method: In an experimental trial to compare implementation formats, 41 Latino families were randomly assigned to EDM action-oriented skills training groups, and 47 families were randomly assigned to unstructured EDM support…

  1. Low-Budget, Cost-Effective OCR: Optical Character Recognition for MS-DOS Micros.

    ERIC Educational Resources Information Center

    Perez, Ernest

    1990-01-01

    Discusses optical character recognition (OCR) for use with MS-DOS microcomputers. Cost effectiveness is considered, three types of software approaches to character recognition are explained, hardware and operation requirements are described, possible library applications are discussed, future OCR developments are suggested, and a list of OCR…

  2. Entre Dos Mundos/Between Two Worlds: Youth Violence Prevention for Acculturating Latino Families

    ERIC Educational Resources Information Center

    Smokowski, Paul R.; Bacallao, Martica

    2009-01-01

    Objective: This study evaluated the efficacy of Entre Dos Mundos/Between Two Worlds (EDM) prevention for Latino adolescents. Method: In an experimental trial to compare implementation formats, 41 Latino families were randomly assigned to EDM action-oriented skills training groups, and 47 families were randomly assigned to unstructured EDM support…

  3. Low-Budget, Cost-Effective OCR: Optical Character Recognition for MS-DOS Micros.

    ERIC Educational Resources Information Center

    Perez, Ernest

    1990-01-01

    Discusses optical character recognition (OCR) for use with MS-DOS microcomputers. Cost effectiveness is considered, three types of software approaches to character recognition are explained, hardware and operation requirements are described, possible library applications are discussed, future OCR developments are suggested, and a list of OCR…

  4. Comparison and evaluation of atmospheric correction algorithms of QUAC, DOS, and FLAASH for HICO hyperspectral imagery

    NASA Astrophysics Data System (ADS)

    Shi, Liangliang; Mao, Zhihua; Chen, Peng; Han, Sha'ou; Gong, Fang; Zhu, Qiankun

    2016-10-01

    In order to obtain the spectral information of objects and improve the retrieval of quantitative parameters from remotely sensing data accurately on land or over water bodies, atmospheric correction is a vital step, certainly, it is also a prerequisite to hyperspectral imagery data analysis approaches. On the base of previous studies, the atmospheric correction algorithms were divided to two categories: image-based empirical and model-based correction methods. The Quick Atmospheric Correction (QUAC) and Dark Object Subtraction (DOS) methods belong to the empirical or semiempirical methods, however, the Fast Line-of-sight Atmospheric Analysis of Spectral Hypercube (FLAASH) method was developed from the radiative transfer model. In this paper, we initially evaluated the performance from Hyperspectral Imager for the Coastal Ocean (HICO) of 16 Nov 2013 using QUAC, DOS, and MODTRAN integrated in FLAASH, and compared the results of these correction methods with in situ data. The results indicate that the method of FLAASH model performs much better than DOS and QUAC in atmospheric correction for HICO hyperspectral imagery, although the DOS and QUAC method is conducted more easily and do not require inputs of complex parameters.

  5. Sedimentation History of Lago Dos Bocas, Puerto Rico, 1942-2005

    USGS Publications Warehouse

    Soler-López, Luis R.

    2007-01-01

    The Lago Dos Bocas Dam, located in the municipality of Utuado in north central Puerto Rico, was constructed in 1942 for hydroelectric power generation. The reservoir had an original storage capacity of 37.50 million cubic meters and a drainage area of 440 square kilometers. In 1948, the construction of the Lago Caonillas Dam on the Rio Caonillas branch of Lago Dos Bocas reduced the natural sediment-contributing drainage area to 310 square kilometers; therefore, the Lago Caonillas Dam is considered an effective sediment trap. Sedimentation in Lago Dos Bocas reservoir has reduced the storage capacity from 37.50 million cubic meters in 1942 to 17.26 million cubic meters in 2005, which represents a storage loss of about 54 percent. The long-term annual water-storage capacity loss rate remained nearly constant at about 320,000 cubic meters per year to about 1997. The inter-survey sedimentation rate between 1997 and 1999, however, is higher than the long-term rate at about 1.09 million cubic meters per year. Between 1999 and 2005 the rate is lower than the long-term rate at about 0.13 million cubic meters per year. The Lago Dos Bocas effective sediment-contributing drainage area had an average sediment yield of about 1,400 cubic meters per square kilometer per year between 1942 and 1997. This rate increased substantially by 1999 to about 4,600 cubic meters per square kilometer per year, probably resulting from the historical magnitude floods caused by Hurricane Georges in 1998. Recent data indicate that the Lago Dos Bocas drainage area sediment yield decreased substantially to about 570 cubic meters per square kilometer per year, which is much lower than the 1942-1997 area normalized sedimentation rate of 1,235 cubic meters per square kilometer per year. The impact of Hurricane Georges on the basin sediment yield could have been the cause of this change, since the magnitude of the floods could have nearly depleted the Lago Dos Bocas drainage area of easily erodible and

  6. 76 FR 25733 - 60-Day Notice of Proposed Information Collection: DS-7001 and DS-7005, DOS-Sponsored Academic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-05

    ... Notice of Proposed Information Collection: DS-7001 and DS- 7005, DOS-Sponsored Academic Exchange Program... preceding submission to OMB. We are conducting this process in accordance with the Paperwork Reduction Act of 1995. Title of Information Collection: DOS-Sponsored Academic Exchange Program Application. OMB...

  7. Observational Assessment of Preschool Disruptive Behavior, Part II: Validity of the Disruptive Behavior Diagnostic Observation Schedule (DB-DOS)

    ERIC Educational Resources Information Center

    Wakschlag, Lauren S.; Briggs-Gowan, Margaret J.; Hill, Carri; Danis, Barbara; Leventhal, Bennett L.; Keenan, Kate; Egger, Helen L.; Cicchetti, Domenic; Burns, James; Carter, Alice S.

    2008-01-01

    A study is conducted to determine whether the multidomain, multicontext Disruptive Behavior Diagnostic Observation Schedule (DB-DOS) is a valid observational method for assessing disruptive behavior of preschool children. It is concluded that the DB-DOS is a valid method for a direct observational assessment of clinically significant disruptive…

  8. Observational Assessment of Preschool Disruptive Behavior, Part II: Validity of the Disruptive Behavior Diagnostic Observation Schedule (DB-DOS)

    ERIC Educational Resources Information Center

    Wakschlag, Lauren S.; Briggs-Gowan, Margaret J.; Hill, Carri; Danis, Barbara; Leventhal, Bennett L.; Keenan, Kate; Egger, Helen L.; Cicchetti, Domenic; Burns, James; Carter, Alice S.

    2008-01-01

    A study is conducted to determine whether the multidomain, multicontext Disruptive Behavior Diagnostic Observation Schedule (DB-DOS) is a valid observational method for assessing disruptive behavior of preschool children. It is concluded that the DB-DOS is a valid method for a direct observational assessment of clinically significant disruptive…

  9. 48 CFR 653.217-70 - DOS form DS-1921, Award/Modification of Interagency Acquisition Agreement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false DOS form DS-1921, Award... Regulations System DEPARTMENT OF STATE CLAUSES AND FORMS FORMS Prescription of Forms 653.217-70 DOS form DS-1921, Award/Modification of Interagency Acquisition Agreement. As prescribed in 617.504-70(b)(5)(i), DS...

  10. Models that Teach about the Computer: AppleWorks and ProDOS, the Computer's Memory and Disk Storage.

    ERIC Educational Resources Information Center

    Niess, Margaret L.

    1989-01-01

    This final article in a series on creating models for teaching about computer memory and disk storage and retrieval focuses on AppleWorks software and the Professional Disk Operating System (ProDOS). Instructions for creating a paper model of the AppleWorks menu system and the ProDOS disk file are given. (LRW)

  11. ACONF DOS

    SciTech Connect

    Atcitty, Stanley; Butler, Paul; Symons, Phlip; & Corey, Garth

    2009-03-25

    ACONF is a system which has been developed by Sandia National Laboratories. ACONF is a system for optimizing the interaction between generator, photovoltaic system, batteries, and load in independent non-grid-tied electrical systems. It is primarily used in rural locations where running utility lines proves costly if it is possible at all. It is controlled by an Ampro PC-104 Coremodule 400 controller system. The code for this system is written in the BASIC programming language. The routine contained in this document was written originally by Phil Symons. ACONF is intended to increase the efficiency of freestanding electrical systems to increase battery life and more efficiently use generator fuel.

  12. Kinetics and dosimetry of thallium-201 in human testes

    SciTech Connect

    Rao, D.V.; Shepstone, B.J.; Wilkins, H.B. ||

    1995-04-01

    Thallous chloride ({sup 201}Tl) is a well-known imaging agent. It has been shown to accumulate in the testes. In view of this, the testicular kinetics of {sup 201}Tl is investigated in humans and the absorbed dose to the organ calculated. Thallous chloride {sup 201}Tl was injected intravenously into four patients for myocardial perfusion studies. After clinical evaluation, the testicular uptake and clearance of {sup 201}Tl were monitored for about 1 wk using a gamma camera. Testicular uptake of {sup 201}Tl was rapid with a mean biological uptake half-time of 0.67 hr and mean biological clearance half-time of 280 hr. The mean maximum testicular uptake of {sup 201}Tl was about 0.4% of the injected activity. These data were utilized to calculate the average absorbed dose to the testes. The absorbed dose to the testes was calculated to be 3.5 x 10{sup {minus}4} Gy/MBq (1.3 rad/mCi) of injected activity. When the relative biological effectiveness of the Auger emitter {sup 201}Tl is taken into account, the equivalent dose to the testes is 9.5 x 10{sup {minus}4} Sv/MBq (3.5 rem/mCi). 14 refs., 1 fig., 2 tabs.

  13. Odor detection ability and thallium-201 transport in the olfactory nerve of traumatic olfactory-impaired mice.

    PubMed

    Shiga, Hideaki; Kinoshita, Yayoi; Washiyama, Kohshin; Ogawa, Daisuke; Amano, Ryohei; Hirota, Kyoko; Tsukatani, Toshiaki; Furukawa, Mitsuru; Miwa, Takaki

    2008-09-01

    Although olfactory nerve damage is a contributing factor in the diagnosis of posttraumatic olfactory loss, at present, there are no methods to directly assess injury to these nerves. We have shown that following olfactory nerve injury in mice, thallium-201 (201 Tl) transport from the nasal cavity to the olfactory bulb decreases. To determine if olfactory function after nerve injury could be assessed with nasal administration of 201 Tl, we measured the correlation between odor detection ability (ODA) and the rate of transport of 201 Tl in olfactory nerves. Both ODA and 201 Tl transport were measured after bilateral olfactory nerve transection for a 4-week period. Cycloheximide solution was used for ODA against tap water. 201 Tl transport was measured as the ratio of radioactivity in the nasal cavity and olfactory bulb with gamma spectrometry. There was a significant correlation between ODA and the rate of 201 Tl transport in the olfactory nerve. These findings suggest that olfactory function after nerve injury can be objectively evaluated with the nasal administration of 201 Tl.

  14. Effect of thallium-201 blood levels on reversible myocardial defects

    SciTech Connect

    Nelson, C.W.; Wilson, R.A.; Angello, D.A.; Palac, R.T.

    1989-07-01

    To determine if /sup 201/Tl plasma blood levels correlate with the presence of reversible myocardial defects during exercise testing, 14 patients with stable coronary artery disease underwent two separate exercise /sup 201/Tl stress tests. Between initial and delayed imaging, on one test the patients drank an instant breakfast drink (eating) and on the other they drank an equivalent volume of water as a control (H/sub 2/O). Thallium-201 imaging was performed immediately postexercise, immediately after eating/H/sub 2/O and 210 min after eating/H/sub 2/O. Between initial and immediate post eating/H/sub 2/O images 201Tl reversible defects occurred in 27/38 regions in the H/sub 2/O test versus 15/38 regions in the eating test (p = 0.02). Over this early time period, plasma /sup 201/Tl activity was significantly higher in the H/sub 2/O test than eating test (p less than 0.05). In conclusion, early reversal of /sup 201/Tl defects may, in part, be the result of higher plasma /sup 201/Tl activity early after initial postexercise /sup 201/Tl imaging.

  15. Fast washout of thallium-201 from area of myocardial infarction: possible artifact of background subtraction

    SciTech Connect

    Brown, K.A.; Benoit, L.; Clements, J.P.; Wackers, F.J.

    1987-06-01

    A recent report described a pattern of reverse redistribution on poststreptokinase /sup 201/Tl studies which was believed to be due to rapid washout of /sup 201/Tl from the infarct area related to reperfusion of the infarct vessel. We have also observed the phenomenon of rapid washout of /sup 201/Tl from the area of infarction in the absence of thrombolytic therapy. This study was undertaken to test the hypothesis that rapid washout of /sup 201/Tl from an area of infarction is an artifact of background subtraction usually employed in analysis of washout. A total of 61 patients with previous myocardial infarction who underwent cardiac catheterization and exercise /sup 201/Tl imaging were examined. Thallium-201 images were analyzed using a validated quantitative method employing interpolative background correction. Abnormally increased /sup 201/Tl washout was noted in 11 infarct segments in 10 (18%) patients. Infarct segments with rapid washout had significantly less initial uptake, and more severe associated wall motion abnormalities than infarct segments with normal washout. When quantitative analysis was repeated without background subtraction, no segments with rapid washout were observed. A phantom model was constructed to further test our hypothesis. The frequency of observed rapid washout was directly related to the severity of the initial defect and was entirely dependent upon utilizing background correction during the quantitative analysis. Our study suggests that rapid washout of /sup 201/Tl in an area of previous infarction reflects an artifact of background subtraction involved with standard quantitative analysis.

  16. Assessment of olfactory nerve by SPECT-MRI image with nasal thallium-201 administration in patients with olfactory impairments in comparison to healthy volunteers.

    PubMed

    Shiga, Hideaki; Taki, Junichi; Washiyama, Kohshin; Yamamoto, Junpei; Kinase, Sakae; Okuda, Koichi; Kinuya, Seigo; Watanabe, Naoto; Tonami, Hisao; Koshida, Kichiro; Amano, Ryohei; Furukawa, Mitsuru; Miwa, Takaki

    2013-01-01

    The aim of this study was to assess whether migration of thallium-201 ((201)Tl) to the olfactory bulb were reduced in patients with olfactory impairments in comparison to healthy volunteers after nasal administration of (201)Tl. 10 healthy volunteers and 21 patients enrolled in the study (19 males and 12 females; 26-71 years old). The causes of olfactory dysfunction in the patients were head trauma (n = 7), upper respiratory tract infection (n = 7), and chronic rhinosinusitis (n = 7). (201)TlCl was administered unilaterally to the olfactory cleft, and SPECT-CT was conducted 24 h later. Separate MRI images were merged with the SPECT images. (201)Tl olfactory migration was also correlated with the volume of the olfactory bulb determined from MRI images, as well as with odor recognition thresholds measured by using T&T olfactometry. Nasal (201)Tl migration to the olfactory bulb was significantly lower in the olfactory-impaired patients than in healthy volunteers. The migration of (201)Tl to the olfactory bulb was significantly correlated with odor recognition thresholds obtained with T&T olfactometry and correlated with the volume of the olfactory bulb determined from MRI images when all subjects were included. Assessment of the (201)Tl migration to the olfactory bulb was the new method for the evaluation of the olfactory nerve connectivity in patients with impaired olfaction.

  17. Effect of modulation frequency bandwidth on measurement accuracy and precision for digital diffuse optical spectroscopy (dDOS)

    NASA Astrophysics Data System (ADS)

    Jung, Justin; Istfan, Raeef; Roblyer, Darren

    2014-03-01

    Near-infrared (NIR) frequency-domain Diffuse Optical Spectroscopy (DOS) is an emerging technology with a growing number of potential clinical applications. In an effort to reduce DOS system complexity and improve portability, we recently demonstrated a direct digital sampling method that utilizes digital signal generation and detection as a replacement for more traditional analog methods. In our technique, a fast analog-to-digital converter (ADC) samples the detected time-domain radio frequency (RF) waveforms at each modulation frequency in a broad-bandwidth sweep (50- 300MHz). While we have shown this method provides comparable results to other DOS technologies, the process is data intensive as digital samples must be stored and processed for each modulation frequency and wavelength. We explore here the effect of reducing the modulation frequency bandwidth on the accuracy and precision of extracted optical properties. To accomplish this, the performance of the digital DOS (dDOS) system was compared to a gold standard network analyzer based DOS system. With a starting frequency of 50MHz, the input signal of the dDOS system was swept to 100, 150, 250, or 300MHz in 4MHz increments and results were compared to full 50-300MHz networkanalyzer DOS measurements. The average errors in extracted μa and μs' with dDOS were lowest for the full 50-300MHz sweep (less than 3%) and were within 3.8% for frequency bandwidths as narrow as 50-150MHz. The errors increased to as much as 9.0% when a bandwidth of 50-100MHz was tested. These results demonstrate the possibility for reduced data collection with dDOS without critical compensation of optical property extraction.

  18. Trace Element Distribution Between Olivine and Kirschsteinite in Angra Dos Reis

    NASA Technical Reports Server (NTRS)

    Fittipaldo, M. M.; Jones, R. H.; Shearer, C. K.

    2003-01-01

    The angrites are a small and enigmatic group of basaltic achondrites that possess unique mineralogical and chemical properties. The dominant mineralogy of the seven angrite members (Angra dos Reis, LEW 86010, LEW 87051, Asuka 881371, Sahara 99555, D Orbigny, and a new Moroccan member) is fassaite, olivine, and plagioclase. Angrites display a wide range of thermal histories, with Angra dos Reis (AdoR) exhibiting a cooling history different from that of the rapidly cooled members and from LEW86010, a more slowly cooled member. AdoR could represent either a cumulate or a porphyritic igneous rock that was later altered by metamorphism. We are re-examining the thermal history of AdoR in light of the more recently described angrite members. Our emphasis is a trace element study of low-Ca olivine, which we refer to as olivine, and high-Ca olivine, which we refer to as kirschsteinite, in AdoR.

  19. Using satellite images to monitor glacial-lake outburst floods: Lago Cachet Dos drainage, Chile

    USGS Publications Warehouse

    Friesen, Beverly A.; Cole, Christopher J.; Nimick, David A.; Wilson, Earl M.; Fahey, Mark J.; McGrath, Daniel J.; Leidich, Jonathan

    2015-01-01

    During 2008–2013, 14 GLOFs were released from Lago Cachet Dos and created environmental and safety concerns for downstream residents and to infrastructure. If GLOFs and the consequent headward erosion continue, the moraine that creates Lago Cachet Uno could be destabilized and breached, and the two lakes could merge. If the two lakes become connected, the volume of future GLOFs likely would be greater and thus cause longer and (or) more extensive flooding downstream. Additional GLOFs from Lago Cachet Dos are expected in the future, and continued environmental monitoring could provide an early warning system as well as scientific information that could increase our understanding of GLOFs and their consequences. GLOFs occur in glaciated areas around the world and remote sensing technologies can allow researchers to better understand—and potentially predict—future GLOF events.

  20. Magnetic field effects on the DOS of a Kondo quantum dot coupled to LL leads

    NASA Astrophysics Data System (ADS)

    Yang, Kai-Hua; Qin, Chang-Dong; Wang, Huai-Yu; Wang, Xu

    2017-01-01

    We investigate the joint effects of a magnetic field and electron-electron interaction on the tunneling density of states (DOS) of a quantum dot coupled to the Luttinger liquid leads in the Kondo regime. We find that for intralead electron interaction, the DOS develops two peaks deviated from the origin by the Zeeman energy. With the increase of the intralead interaction, a phase transition occurs. For moderately strong interaction, the Zeeman splitting peaks develop into two dips. The splitting of the Kondo peak and dip is not symmetric with respect to up and down spins. In the limit of strong interaction the Zeeman splitting behavior disappears and there appears a power-law scaling behavior.

  1. Application of a sparse matrix design strategy to the synthesis of dos libraries.

    PubMed

    Akella, Lakshmi B; Marcaurelle, Lisa A

    2011-07-11

    We have implemented an interactive and practical sparse matrix design strategy for the synthesis of DOS libraries, which facilitates the selection of diverse library members within a user-defined range of physicochemical properties while still maintaining synthetic efficiency. The utility of this approach is illustrated with the synthesis of an 8000-membered library of stereochemically diverse medium-sized rings accessible via a build/couple/pair DOS strategy. Diverse library members were selected from a virtual library by applying the maximum dissimilarity method, while the selection of similar analogs around each diverse product was ensured by picking near neighbors algorithmically based on fingerprint comparison. Adjustable filters on compound properties, which can be tailored to suit the needs of the target biology, facilitated subset selection from the synthetically accessible compounds.

  2. A Comparison of Three LISP Interpreters for MS-DOS-Based Microcomputers

    PubMed Central

    Kahane, Stephen N.; Johannes, Richard S.

    1985-01-01

    We report a comparison of three commercially available LISP interpreters running on MS-DOS-based microcomputers. Marked differences were found between the different products' memory addressing abilities, error handling and debugging facilities. Editing tools, tutoring environments, windowing, graphic capabilities, operating system and port call facilities are also contrasted. Speed was tested via a group of LISP functions (benchmarks) that attempt to isolate list manipulation, iteration, function calling, recursion and mathematical calculation performance.

  3. Adaptive Suspicious Prevention for Defending DoS Attacks in SDN-Based Convergent Networks

    PubMed Central

    Dao, Nhu-Ngoc; Kim, Joongheon; Park, Minho; Cho, Sungrae

    2016-01-01

    The convergent communication network will play an important role as a single platform to unify heterogeneous networks and integrate emerging technologies and existing legacy networks. Although there have been proposed many feasible solutions, they could not become convergent frameworks since they mainly focused on converting functions between various protocols and interfaces in edge networks, and handling functions for multiple services in core networks, e.g., the Multi-protocol Label Switching (MPLS) technique. Software-defined networking (SDN), on the other hand, is expected to be the ideal future for the convergent network since it can provide a controllable, dynamic, and cost-effective network. However, SDN has an original structural vulnerability behind a lot of advantages, which is the centralized control plane. As the brains of the network, a controller manages the whole network, which is attractive to attackers. In this context, we proposes a novel solution called adaptive suspicious prevention (ASP) mechanism to protect the controller from the Denial of Service (DoS) attacks that could incapacitate an SDN. The ASP is integrated with OpenFlow protocol to detect and prevent DoS attacks effectively. Our comprehensive experimental results show that the ASP enhances the resilience of an SDN network against DoS attacks by up to 38%. PMID:27494411

  4. Adaptive Suspicious Prevention for Defending DoS Attacks in SDN-Based Convergent Networks.

    PubMed

    Dao, Nhu-Ngoc; Kim, Joongheon; Park, Minho; Cho, Sungrae

    2016-01-01

    The convergent communication network will play an important role as a single platform to unify heterogeneous networks and integrate emerging technologies and existing legacy networks. Although there have been proposed many feasible solutions, they could not become convergent frameworks since they mainly focused on converting functions between various protocols and interfaces in edge networks, and handling functions for multiple services in core networks, e.g., the Multi-protocol Label Switching (MPLS) technique. Software-defined networking (SDN), on the other hand, is expected to be the ideal future for the convergent network since it can provide a controllable, dynamic, and cost-effective network. However, SDN has an original structural vulnerability behind a lot of advantages, which is the centralized control plane. As the brains of the network, a controller manages the whole network, which is attractive to attackers. In this context, we proposes a novel solution called adaptive suspicious prevention (ASP) mechanism to protect the controller from the Denial of Service (DoS) attacks that could incapacitate an SDN. The ASP is integrated with OpenFlow protocol to detect and prevent DoS attacks effectively. Our comprehensive experimental results show that the ASP enhances the resilience of an SDN network against DoS attacks by up to 38%.

  5. FlexyDos3D: a deformable anthropomorphic 3D radiation dosimeter: radiation properties

    NASA Astrophysics Data System (ADS)

    De Deene, Y.; Skyt, P. S.; Hil, R.; Booth, J. T.

    2015-02-01

    Three dimensional radiation dosimetry has received growing interest with the implementation of highly conformal radiotherapy treatments. The radiotherapy community faces new challenges with the commissioning of image guided and image gated radiotherapy treatments (IGRT) and deformable image registration software. A new three dimensional anthropomorphically shaped flexible dosimeter, further called ‘FlexyDos3D’, has been constructed and a new fast optical scanning method has been implemented that enables scanning of irregular shaped dosimeters. The FlexyDos3D phantom can be actuated and deformed during the actual treatment. FlexyDos3D offers the additional advantage that it is easy to fabricate, is non-toxic and can be molded in an arbitrary shape with high geometrical precision. The dosimeter formulation has been optimized in terms of dose sensitivity. The influence of the casting material and oxygen concentration has also been investigated. The radiophysical properties of this new dosimeter are discussed including stability, spatial integrity, temperature dependence of the dosimeter during radiation, readout and storage, dose rate dependence and tissue equivalence. The first authors Y De Deene and P S Skyt made an equivalent contribution to the experimental work presented in this paper.

  6. Intracardiac malignant lymphoma detected by gallium-67 citrate and thallium-201 chloride

    SciTech Connect

    Hamada, S.; Nishimura, T.; Hayashida, K.; Uehara, T.

    1988-11-01

    An abnormal uptake of /sup 67/Ga and /sup 201/Tl in the right atrium was observed initially in a 77-yr-old man with superior vena cava syndrome. The pathological diagnosis of the surgically resected specimen was non-Hodgkin's malignant lymphoma in the right atrium. Thallium-201 is used as an imaging agent for malignant tumors. However, previous reports suggested that /sup 201/Tl scintigraphy may not be a useful method to detect cardiac involvement in patients with malignant neoplasms. In this case both /sup 201/Tl and /sup 67/Ga accumulation was observed in the intracardiac tumor by scintigraphy.

  7. OptaDOS: A tool for obtaining density of states, core-level and optical spectra from electronic structure codes

    NASA Astrophysics Data System (ADS)

    Morris, Andrew J.; Nicholls, Rebecca J.; Pickard, Chris J.; Yates, Jonathan R.

    2014-05-01

    We present OptaDOS, a program for calculating core-electron and low-loss electron energy loss spectra (EELS) and optical spectra along with total-, projected- and joint-density of electronic states (DOS) from single-particle eigenenergies and dipole transition coefficients. Energy-loss spectroscopy is an important tool for probing bonding within a material. Interpreting these spectra can be aided by first principles calculations. The spectra are generated from the eigenenergies through integration over the Brillouin zone. An important feature of this code is that this integration is performed using a choice of adaptive or linear extrapolation broadening methods which we show produces higher accuracy spectra than standard fixed-width Gaussian broadening. OptaDOS may be straightforwardly interfaced to any electronic structure code. OptaDOS is freely available under the GNU General Public licence from http://www.optados.org.

  8. T cell responses to DosR and Rpf proteins in actively and latently infected individuals from Colombia.

    PubMed

    Riaño, Felipe; Arroyo, Leonar; París, Sara; Rojas, Mauricio; Friggen, Annemieke H; van Meijgaarden, Krista E; Franken, Kees L M C; Ottenhoff, Tom H M; García, Luis F; Barrera, Luis F

    2012-03-01

    Mycobacterium tuberculosis DosR regulon-encoded proteins elicit strong immune T-cell responses in individuals with latent tuberculosis (LTBI). Also, resuscitation (Rpf) proteins can induce such responses. However, variations in the immunogenicity of the DosR and Rpf proteins have been observed in European and African populations, and no data are published from other geographic areas. In Colombian LTBI and patients with recently diagnosed PTB, we therefore studied the immune response to DosR, Rpf, stress, and nominal antigens from Mtb, in 7-day stimulated cultures. Three DosR (Rv1737c, Rv2029c, Rv2628c) and 2 Rpf (Rv0867 and Rv2389c) antigens were recognized most prominently on the basis of the net IFNγ production (DosR) or the percentage of responding individuals (Rpf). Results show that the selected DosR antigens induced a higher proportion of CD4-T cells producing IFNγ from LTBI, compared to pulmonary TB patients (PTB), while there were no differences in the proportion of CD8-T cells. An increased frequency of CD4, but not CD8 T-cells with a CD45RO(+)CD27(+) phenotype was observed in LTBI in response to Rv2029c, Rv0867c, and Rv2389c, compared to PTB. The levels of cytokines and chemokines in the supernatants of stimulated cells, showed that the DosR and Rpf antigens induced higher levels of IFNγ in cultures from LTBI compared to PTB, although the induced pattern of cytokines and chemokines was also antigen dependent. In summary, our results are consistent with the significant immunogenicity of Mtb DosR and Rpf antigens in LTBI individuals, and confirm and extend previously reported data from other TB affected human populations.

  9. DoS detection in IEEE 802.11 with the presence of hidden nodes

    PubMed Central

    Soryal, Joseph; Liu, Xijie; Saadawi, Tarek

    2013-01-01

    The paper presents a novel technique to detect Denial of Service (DoS) attacks applied by misbehaving nodes in wireless networks with the presence of hidden nodes employing the widely used IEEE 802.11 Distributed Coordination Function (DCF) protocols described in the IEEE standard [1]. Attacker nodes alter the IEEE 802.11 DCF firmware to illicitly capture the channel via elevating the probability of the average number of packets transmitted successfully using up the bandwidth share of the innocent nodes that follow the protocol standards. We obtained the theoretical network throughput by solving two-dimensional Markov Chain model as described by Bianchi [2], and Liu and Saadawi [3] to determine the channel capacity. We validated the results obtained via the theoretical computations with the results obtained by OPNET simulator [4] to define the baseline for the average attainable throughput in the channel under standard conditions where all nodes follow the standards. The main goal of the DoS attacker is to prevent the innocent nodes from accessing the channel and by capturing the channel’s bandwidth. In addition, the attacker strives to appear as an innocent node that follows the standards. The protocol resides in every node to enable each node to police other nodes in its immediate wireless coverage area. All innocent nodes are able to detect and identify the DoS attacker in its wireless coverage area. We applied the protocol to two Physical Layer technologies: Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping Spread Spectrum (FHSS) and the results are presented to validate the algorithm. PMID:25685510

  10. DoS detection in IEEE 802.11 with the presence of hidden nodes.

    PubMed

    Soryal, Joseph; Liu, Xijie; Saadawi, Tarek

    2014-07-01

    The paper presents a novel technique to detect Denial of Service (DoS) attacks applied by misbehaving nodes in wireless networks with the presence of hidden nodes employing the widely used IEEE 802.11 Distributed Coordination Function (DCF) protocols described in the IEEE standard [1]. Attacker nodes alter the IEEE 802.11 DCF firmware to illicitly capture the channel via elevating the probability of the average number of packets transmitted successfully using up the bandwidth share of the innocent nodes that follow the protocol standards. We obtained the theoretical network throughput by solving two-dimensional Markov Chain model as described by Bianchi [2], and Liu and Saadawi [3] to determine the channel capacity. We validated the results obtained via the theoretical computations with the results obtained by OPNET simulator [4] to define the baseline for the average attainable throughput in the channel under standard conditions where all nodes follow the standards. The main goal of the DoS attacker is to prevent the innocent nodes from accessing the channel and by capturing the channel's bandwidth. In addition, the attacker strives to appear as an innocent node that follows the standards. The protocol resides in every node to enable each node to police other nodes in its immediate wireless coverage area. All innocent nodes are able to detect and identify the DoS attacker in its wireless coverage area. We applied the protocol to two Physical Layer technologies: Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping Spread Spectrum (FHSS) and the results are presented to validate the algorithm.

  11. Studies of Brazilian meteorites. III - Origin and history of the Angra dos Reis achondrite

    NASA Technical Reports Server (NTRS)

    Prinz, M.; Keil, K.; Hlava, P. F.; Berkley, J. L.; Gomes, C. B.; Curvello, W. S.

    1977-01-01

    The mineral composition of the Angra dos Reis meteorite, which fell in 1869, is described. This achondrite contains phases reported in a meteorite for the first time. Petrofabric analysis shows that fassaite has a preferred orientation and lineation, which is interpreted as being due to cumulus processes, possibly the effect of post-depositional magmatic current flow or laminar flow of a crystalline mush. The mineral chemistry indicates crystallization from a highly silica-undersaturated melt at low pressure. Several aspects of the mineral composition are discussed with reference to the implications of crystallization conditions.

  12. Anaerobic Mycobacterium tuberculosis cell death stems from intracellular acidification mitigated by the DosR regulon.

    PubMed

    Reichlen, Matthew J; Leistikow, Rachel L; Scobey, Micah S; Born, Sarah E M; Voskuil, Martin I

    2017-09-05

    Mycobacterium tuberculosis (Mtb) is a strict aerobe capable of prolonged survival in the absence of oxygen. We investigated the ability of anaerobic Mtb to counter challenges to internal pH homeostasis in the absence of aerobic respiration, the primary mechanism of proton efflux for aerobic bacilli. Anaerobic Mtb populations were markedly impaired for survival under a mildly acidic pH relative to standard culture conditions. Acidic environmental pH greatly increased the susceptibility of anaerobic bacilli to collapse of proton motive force by protonophores, to antimicrobial compounds that target entry into the electron transport system, and to small organic acids with uncoupling activity. However, anaerobic bacilli exhibited high tolerance to these challenges at near neutral pH. At a slightly alkaline pH which was near the optimum intracellular pH, protonophore addition even improved long-term bacilli survival. Although anaerobic Mtb in acidic conditions maintained 40% lower ATP levels than bacilli at standard culture conditions, ATP loss alone could not explain the viability drop. Protonophores decreased ATP levels by more than 90% regardless of extracellular pH but were bactericidal only under acidic conditions, indicating anaerobic bacilli could survive extreme ATP loss provided the external pH was within viable intracellular parameters. Acidic conditions drastically decreased anaerobic survival of a DosR mutant while an alkaline environment improved survival of the DosR mutant. Together these findings indicate intracellular acidification is a primary challenge for anaerobic Mtb survival and that the DosR regulon plays a critical role in sustaining internal pH homeostasis.Importance: During infection, Mtb bacilli are prevalent in environments largely devoid of oxygen. Yet the factors that influence survival of these severely growth- and metabolically-limited bacilli remain poorly understood. We determined how anaerobic bacilli respond to fluctuations in

  13. Volcanic and structural controls of mineralization in the Dos Cabezas Mountains of southeastern Arizona

    SciTech Connect

    Drewes, H.; Klein, D.P.; Birmingham, S.D.

    1988-01-01

    A combination of geophysical, geochemical, and geological features suggests that a central part of the Dos Cabezas Mountains probably has considerable potential for blind deposits, chiefly base metals. The area exposes the root zone of a Paleocene( ) volcanic complex and its underlying granitic stocks, which were emplaced next to a major northwest-trending, much reactivated fault zone. The new data, combined with the knowledge of past mining activity in the area, lead them to propose several exploration targets that may lead to ore bodies in breccia pipes along the base of the volcanic pile and along a possible concealed fault or caldera margin.

  14. Pinch-off dynamics and dripping-onto-substrate (DoS) rheometry of complex fluids.

    PubMed

    Dinic, Jelena; Jimenez, Leidy Nallely; Sharma, Vivek

    2017-01-31

    Liquid transfer and drop formation/deposition processes involve complex free-surface flows including the formation of columnar necks that undergo spontaneous capillary-driven instability, thinning and pinch-off. For simple (Newtonian and inelastic) fluids, a complex interplay of capillary, inertial and viscous stresses determines the nonlinear dynamics underlying finite-time singularity as well as self-similar capillary thinning and pinch-off dynamics. In rheologically complex fluids, extra elastic stresses as well as non-Newtonian shear and extensional viscosities dramatically alter the nonlinear dynamics. Stream-wise velocity gradients that arise within the thinning columnar neck create an extensional flow field, and many complex fluids exhibit a much larger resistance to elongational flows than Newtonian fluids with similar shear viscosity. Characterization of pinch-off dynamics and the response to both shear and extensional flows that influence drop formation/deposition in microfluidic and printing applications requires bespoke instrumentation not available, or easily replicated, in most laboratories. Here we show that dripping-onto-substrate (DoS) rheometry protocols that involve visualization and analysis of capillary-driven thinning and pinch-off dynamics of a columnar neck formed between a nozzle and a sessile drop can be used for measuring shear viscosity, power law index, extensional viscosity, relaxation time and the most relevant processing timescale for printing. We showcase the versatility of DoS rheometry by characterizing and contrasting the pinch-off dynamics of a wide spectrum of simple and complex fluids: water, printing inks, semi-dilute polymer solutions, yield stress fluids, food materials and cosmetics. We show that DoS rheometry enables characterization of low viscosity printing inks and polymer solutions that are beyond the measurable range of commercially-available capillary break-up extensional rheometer (CaBER). We show that for high

  15. Age and isotopic relationships among the angrites Lewis Cliff 86010 and Angra dos Reis

    SciTech Connect

    Lugmair, G.W. ); Galer, S.J.G. Max-Planck-Inst. fuer Chemie, Mainz )

    1992-04-01

    Results of a wide-ranging isotopic investigation of the unique Antarctican angrite LEW-86010 (LEW) are presented, together with a reassessment of the type angrite Angra dos Reis (ADOR). The principal objectives of this study are to obtain precise radiometric ages, initial Sr isotopic compositions, and to search for the erstwhile presence of the short-lived nuclei {sup 146}Sm and {sup 26}Al via their daughter products. The isotopic compositions of Sm, U, Ca, and Ti were also measured. This allows a detailed appraisal to be made of the relations between, and the genealogy of, these two angrites.

  16. PrDOS: prediction of disordered protein regions from amino acid sequence.

    PubMed

    Ishida, Takashi; Kinoshita, Kengo

    2007-07-01

    PrDOS is a server that predicts the disordered regions of a protein from its amino acid sequence (http://prdos.hgc.jp). The server accepts a single protein amino acid sequence, in either plain text or FASTA format. The prediction system is composed of two predictors: a predictor based on local amino acid sequence information and one based on template proteins. The server combines the results of the two predictors and returns a two-state prediction (order/disorder) and a disorder probability for each residue. The prediction results are sent by e-mail, and the server also provides a web-interface to check the results.

  17. Use of Remote Sensing and Local Knowledge for Geoconservation of Regiao dos Lagos, Brazil

    NASA Astrophysics Data System (ADS)

    Avelar, S.; Vasconcelos, G.; Mansur, K. L.; Anjos, S. C.

    2013-12-01

    A series of lagoons can be found along the coastline of Rio de Janeiro, in the so-called Regiao dos Lagos. The lagoons differ in size, physicochemical, sedimentological and biological characteristics. Rare examples of litifying microbialites that produce stromatolites, the oldest fossils on Earth, can be found living in this lagoon system. The occurrence of stromatolites in the region is of great scientific interest because it enables the study of possible analogues of the earliest life on Earth. However, this region has been suffering from intense human activities and degradations. Geoconservation planning requires an assessment of the characteristics of the region and its potential threats. The primary goal of this study is to assess physical environmental changes and anthropogenic impacts over the last four decades in Regiao dos Lagos. Using a broad integrative assessment combining remote sensing, GIS, field studies and local knowledge of communities, land-cover and land-use classes were identified, as well as the main human activities impacting the environment. The seasonal and weekend tourism and urban sprawl in this coastal area of Rio de Janeiro triggers the occupation of new areas and the removal of natural vegetation, especially on lagoon margins. This disorderly occupation by an ever increasing population, with both legal and illegal constructions and the subsequent overload of the local infrastructure, e.g. increase of electrical energy consumption, volume of vehicles, pollution in air, water and soil and problems with water supply and wastewater treatment, are hastening the gradual degradation of the lake ecosystem. The main driving forces to environmental changes over the last four decades in Regiao dos Lagos were the change of dense vegetation, saline and bare soil classes into built-up areas, adding to the poor waste treatment and inadequate sewage disposal. This analysis provides a basis for a better control of anthropogenic impacts and

  18. The Intraplate Seismogenic Zone of Porto dos Gauchos in the Amazon Craton, Brazil

    NASA Astrophysics Data System (ADS)

    Barros, L. V.; Assumpcao, M. S.; Quintero, R. Q.

    2007-05-01

    The Porto dos Gauchos Seismogenic Zone (PGSZ), in the center north of Mato Grosso State, in the contact between the southern Amazonian Craton and northern Parecis Basin, represents one of the most important area of seismic activity in Brazil, with the largest magnitude ever observed in the stable continent of the South America plate (6.2 mb on January 31, 1955). Focal mechanism studies indicated a pure reverse faulting regime with compressional SHmax. oriented in SE-NW direction. After the 1955 earthquake, located in Serra do Tombador, a recurrent seismicity has been detected in Porto dos Gauchos, 100 km northeast of Serra do Tombador. No recent events have been detected in the area of the 1955 epicenter, suggesting a long recurrence time or mislocation of Serra do Tombador earthquake. The Porto dos Gauchos recurrent seismicity has been observed since 1959, when a 4.5 macroseismic estimated magnitude was felt by local inhabitants settled in that remote area two years earlier. In subsequent years, with deployment of regional stations in Brazilian Amazon region earthquakes were detected in 1981 (3.8 mb), 1989 (3.3 mb), 1993 (3.8 mb), 1996 (4.4 mb), 1997 (3.3 mb), and finally on March 10, 1998 (5.1 mb). The aftershocks of 1998 main shock were studied with a local network with up to eight 3- component stations. Such network detected more than 2500 events until December of 2002, when the network was deactivated, but only 100 were accurately located. Based on this set of events and a controlled source experiment we determined a 1-D velocity model for the area, a composite focal mechanism with P wave polarities, spectral analysis studies to estimate the source dimension, stress drop and moment magnitudes for the main shock and some others events of the set. On March 23, 2005 another shock occurred in the same seismogenic area of Porto dos Gauchos, with magnitude 4.7 to 5.0. One week later five stations were installed again to monitor the aftershock activity, detecting

  19. RighTime: A real time clock correcting program for MS-DOS-based computer systems

    NASA Technical Reports Server (NTRS)

    Becker, G. Thomas

    1993-01-01

    A computer program is described which effectively eliminates the misgivings of the DOS system clock in PC/AT-class computers. RighTime is a small, sophisticated memory-resident program that automatically corrects both the DOS system clock and the hardware 'CMOS' real time clock (RTC) in real time. RighTime learns what corrections are required without operator interaction beyond the occasional accurate time set. Both warm (power on) and cool (power off) errors are corrected, usually yielding better than one part per million accuracy in the typical desktop computer with no additional hardware, and RighTime increases the system clock resolution from approximately 0.0549 second to 0.01 second. Program tools are also available which allow visualization of RighTime's actions, verification of its performance, display of its history log, and which provide data for graphing of the system clock behavior. The program has found application in a wide variety of industries, including astronomy, satellite tracking, communications, broadcasting, transportation, public utilities, manufacturing, medicine, and the military.

  20. Quality control and assurance for validation of DOS/I measurements

    NASA Astrophysics Data System (ADS)

    Cerussi, Albert; Durkin, Amanda; Kwong, Richard; Quang, Timothy; Hill, Brian; Tromberg, Bruce J.; MacKinnon, Nick; Mantulin, William W.

    2010-02-01

    Ongoing multi-center clinical trials are crucial for Biophotonics to gain acceptance in medical imaging. In these trials, quality control (QC) and assurance (QA) are key to success and provide "data insurance". Quality control and assurance deal with standardization, validation, and compliance of procedures, materials and instrumentation. Specifically, QC/QA involves systematic assessment of testing materials, instrumentation performance, standard operating procedures, data logging, analysis, and reporting. QC and QA are important for FDA accreditation and acceptance by the clinical community. Our Biophotonics research in the Network for Translational Research in Optical Imaging (NTROI) program for breast cancer characterization focuses on QA/QC issues primarily related to the broadband Diffuse Optical Spectroscopy and Imaging (DOS/I) instrumentation, because this is an emerging technology with limited standardized QC/QA in place. In the multi-center trial environment, we implement QA/QC procedures: 1. Standardize and validate calibration standards and procedures. (DOS/I technology requires both frequency domain and spectral calibration procedures using tissue simulating phantoms and reflectance standards, respectively.) 2. Standardize and validate data acquisition, processing and visualization (optimize instrument software-EZDOS; centralize data processing) 3. Monitor, catalog and maintain instrument performance (document performance; modularize maintenance; integrate new technology) 4. Standardize and coordinate trial data entry (from individual sites) into centralized database 5. Monitor, audit and communicate all research procedures (database, teleconferences, training sessions) between participants ensuring "calibration". This manuscript describes our ongoing efforts, successes and challenges implementing these strategies.

  1. Reproductive Dynamics of Sterna hirundinacea Lesson, 1831 in Ilha dos Cardos, Santa Catarina, Brazil

    PubMed Central

    Fracasso, Hélio Augusto Alves; Branco, Joaquim Olinto; Efe, Márcio Amorim

    2014-01-01

    In this work, we intend to describe the reproductive dynamics of Sterna hirundinacea in an island from South Brazil. We studied the reproductive biology of this species in its natural environment and provide data on their growth, survival, and reproductive success in Ilha dos Cardos, Santa Catarina, South Brazil. Samplings were carried out daily on the island throughout the reproductive seasons of 2003, 2005, and 2006 and the different stages of development of the chicks were characterized according to age, length of the beak, and plumage characteristics. We provide a basic equation Lm = 167.91 (1 − e −0.062t−(−0.23)) to determine the approximate age of individuals using their body mass. The main cause of chick mortality on the island was natural (63.17% in 2003, 81.41% in 2005, and 79.96% in 2006), whereas predation contributed to mortality in a proportion of 38.83% in 2003, 18.59% in 2005, and 20.04% in 2006. The absence in the area of the chicks' main predator, Kelp gull (Larus dominicanus), the large number of chicks that reached the final stages of development, and their reproductive success demonstrate that Ilha dos Cardos is an important breeding site for the species in southern Brazil. PMID:24977100

  2. Electron spin resonance dating of megafauna from Lagoa dos Porcos, Piauí, Brazil.

    PubMed

    Kinoshita, Angela; Mayer, Elver; Ribau Mendes, Vinícius; Figueiredo, Ana Maria G; Baffa, Oswaldo

    2014-06-01

    Excavations performed at Lagoa dos Porcos site revealed a vast amount of extinct mammal fossil remains, becoming one of the richest palaeontological occurrences in the Serra da Capivara National Park region, a UNESCO World Heritage. Although anatomic and taxonomic aspects of extinct Quaternary mammals are relatively well known, chronologic information for deposits is rare. In this context, electron spin resonance (ESR) dating of megafauna samples provides important information for establishing a chronological background. This work presents the ESR dating of two teeth, one of Gomphotheriidae and other of Toxodontinae. Dose-response curves of each sample were constructed using spectra acquired with a JEOL FA-200 X-Band spectrometer resulting in equivalent dose (De) of 220 ± 40 Gy and 39 ± 2 Gy for Toxodontinae and Gomphotheriidae tooth, respectively. The conversion of De in age was made using ROSY ESR dating software resulting in 26 ± 4 and 22 ± 3 ka. These results place Lagoa dos Porcos fossil assemblage within the Late Pleistocene. These dates overlap with a period of abrupt increase in rainfall in northeast Brazil, and it is possible that this environmental change is related to the formation of this deposit.

  3. Prevalence and predictors of orthorexia nervosa among German students using the 21-item-DOS.

    PubMed

    Depa, Julia; Schweizer, Jenny; Bekers, Sandra-Kristin; Hilzendegen, Carolin; Stroebele-Benschop, Nanette

    2017-03-01

    Orthorexia nervosa (ON) describes the constant pathological preoccupation with "healthy" nutrition. The current results regarding the prevalence of ON differ widely possibly because of invalid measurement tools. This study aimed to investigate ON prevalence in a sample of German students and to examine age, gender, semester, and nutritional knowledge as potential predictors of ON by comparing nutrition science (NS) with economics (ES) students. A total of 446 university students participated in the survey (NS 188, ES 268). ON was determined using the 21-item-DOS, which is a well-constructed, validated, and reliability-tested questionnaire. Age, gender, and semester were also assessed. Of the total sample, 3.3 % were classified as having ON and 9.0 % were at risk of developing ON. Older students scored significantly higher on the subscale "avoidance of additives" compared with younger students and students of lower semester suffered significantly more often from ON than students of higher semester. In addition, comparing field of study showed no significant difference in the prevalence of ON or the risk of developing ON between female NS and ES students. However, mean values for the three DOS subscales were higher among female NS students, albeit far below values indicating pathological behavior. The prevalence of ON appears to be low in this sample of German university students. Female NS students do not seem to have higher prevalence of ON or risk of developing ON.

  4. "Las Dos Cosas," or Why Mexican American Mothers Breast-Feed, But Not for Long.

    PubMed

    Flores, Angela; Anchondo, Inés; Huang, Cindy; Villanos, MariaTeresa; Finch, Casey

    2016-01-01

    To determine why mothers in El Paso, Texas, choose to breast-feed but not exclusively and why breast-feeding duration is short. This was a cross-sectional observational study of 300, mostly Mexican American, low-income mothers delivering at a county hospital who answered questions about breast-feeding and formula feeding, sociodemographics, and health habits. Most mothers (92.6%) in our study initiated breast-feeding, but only 20.3% breast-fed exclusively at the time of hospital discharge. Most mothers (73%) self-identified as Mexicans or Mexican Americans living on the border of the United States and Mexico. Mothers in our study chose to breast-feed if they decided to breast-feed during pregnancy, had breast-fed a previous child, had support from a female relative, and had attended college. Distinctively, most mothers in our study chose "las dos cosas" or to breast-feed and formula feed together early after birth. Acculturation failed to explain the breast-feeding decisions. Mexican American mothers who decided to breast-feed during pregnancy, breast-fed another child, attended college, and enlist a female relative's breast-feeding help were more likely to choose breast-feeding exclusively. Most Mexican American low-income mothers in our study chose "las dos cosas."

  5. RighTime: A real time clock correcting program for MS-DOS-based computer systems

    NASA Technical Reports Server (NTRS)

    Becker, G. Thomas

    1993-01-01

    A computer program is described which effectively eliminates the misgivings of the DOS system clock in PC/AT-class computers. RighTime is a small, sophisticated memory-resident program that automatically corrects both the DOS system clock and the hardware 'CMOS' real time clock (RTC) in real time. RighTime learns what corrections are required without operator interaction beyond the occasional accurate time set. Both warm (power on) and cool (power off) errors are corrected, usually yielding better than one part per million accuracy in the typical desktop computer with no additional hardware, and RighTime increases the system clock resolution from approximately 0.0549 second to 0.01 second. Program tools are also available which allow visualization of RighTime's actions, verification of its performance, display of its history log, and which provide data for graphing of the system clock behavior. The program has found application in a wide variety of industries, including astronomy, satellite tracking, communications, broadcasting, transportation, public utilities, manufacturing, medicine, and the military.

  6. Crystal Structures of the Response Regulator DosR From Mycobacterium Tuberculosis Suggest a Helix Rearrangement Mechanism for Phosphorylation Activation

    SciTech Connect

    Wisedchaisri, G.; Wu, M.; Sherman, D.R.; Hol, W.G.J.

    2009-05-26

    The response regulator DosR is essential for promoting long-term survival of Mycobacterium tuberculosis under low oxygen conditions in a dormant state and may be responsible for latent tuberculosis in one-third of the world's population. Here, we report crystal structures of full-length unphosphorylated DosR at 2.2 {angstrom} resolution and its C-terminal DNA-binding domain at 1.7 {angstrom} resolution. The full-length DosR structure reveals several features never seen before in other response regulators. The N-terminal domain of the full-length DosR structure has an unexpected ({beta}{alpha}){sub 4} topology instead of the canonical ({beta}{alpha}){sub 5} fold observed in other response regulators. The linker region adopts a unique conformation that contains two helices forming a four-helix bundle with two helices from another subunit, resulting in dimer formation. The C-terminal domain in the full-length DosR structure displays a novel location of helix {alpha}10, which allows Gln199 to interact with the catalytic Asp54 residue of the N-terminal domain. In contrast, the structure of the DosR C-terminal domain alone displays a remarkable unstructured conformation for helix {alpha}10 residues, different from the well-defined helical conformations in all other known structures, indicating considerable flexibility within the C-terminal domain. Our structures suggest a mode of DosR activation by phosphorylation via a helix rearrangement mechanism.

  7. Crystal Structures of the Response Regulator DosR from Mycobacterium tuberculosis Suggest a Helix Rearrangement Mechanism for Phosphorylation Activation

    PubMed Central

    Wisedchaisri, Goragot; Wu, Meiting; Sherman, David R.; Hol, Wim G. J.

    2008-01-01

    The response regulator DosR is essential for promoting long-term survival of Mycobacterium tuberculosis under low oxygen conditions in a dormant state and may be responsible for latent tuberculosis in one third of the world’s population. Here we report crystal structures of full-length unphosphorylated DosR at 2.2 Å and its C-terminal DNA-binding domain at 1.7 Å resolution. The full-length DosR structure reveals several features never seen before in other response regulators. The N-terminal domain of the full-length DosR structure has an unexpected (βα)4 topology instead of the canonical (βα)5 fold observed in other response regulators. The linker region adopts a unique conformation which contains two helices forming a four-helix bundle with two helices from another subunit, resulting in dimer formation. The C-terminal domain in the full-length DosR structure displays a novel location of helix α10 which provides Gln199 to interact with the catalytic Asp54 residue of the N-terminal domain. In contrast, the structure of the DosR C-terminal domain alone displays a remarkable unstructured conformation for helix α10 residues different from the well-defined helical conformations in all other known structures, indicating considerable flexibility within the C-terminal domain. Our structures suggest a mode of DosR activation by phosphorylation via a helix rearrangement mechanism. PMID:18353359

  8. Thallium-201 single photon emission tomography after injecting an antimuscarinic agent compared with computed tomography for the diagnosis of recurrent colorectal cancer. Report of three cases.

    PubMed

    Fallahi, Babak; Beiki, Davood; Assadi, Majid; Esfahani, Armaghan Fard

    2006-01-01

    Thallium-201 chloride ((201)TlCl) is frequently used for imaging of a variety of malignant tumors viz., thyroid, lung, brain, bone and breast, however in patients with colorectal cancer, its role is not well established. In this case report we present three patients with colorectal cancer recurrence, with inconclusive computed tomography (CT) findings while (201)TlCl single photon emission tomography (SPET) after injecting an anti-muscarinic agent, showed findings corroborating with the final diagnosis. Correlating CT with (201)TlCl-SPET findings, recurrence of the colorectal cancer was diagnosed in two cases; surgical treatment accordingly planned, confirmed the diagnosis. In the third case, CT was falsely positive while (201)TlCl-SPET was negative, compatible with the final diagnosis.

  9. 10 CFR Appendix L to Part 110 - Illustrative List of Byproduct Materials Under NRC Export/Import Licensing Authority a

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 131m) Tellurium 132 (Te 132) Terbium 160 (Tb 160) Thallium 200 (Tl 200) Thallium 201 (Tl 201) Thallium 202 (Tl 202) Thallium 204 (Tl 204) Thulium 170 (Tm 170) Thulium 171 (Tm 171) Tin 113 (Sn 113) Tin 123...

  10. Role of thallium-201 total-body scintigraphy in follow-up of thyroid carcinoma

    SciTech Connect

    Hoefnagel, C.A.; Delprat, C.C.; Marcuse, H.R.; de Vijlder, J.J.

    1986-12-01

    To evaluate the reliability of total-body scintigraphy using (/sup 201/Tl)chloride in postoperative follow-up of thyroid carcinoma, this procedure was performed in 326 patients after total thyroidectomy for thyroid carcinoma. The results were compared with those of 131I scintigraphy and thyroglobulin assays. /sup 201/Tl total-body scintigraphy was found to have the greatest sensitivity (94%), whereas /sup 131/I scintigraphy had the highest specificity (99%). It is shown that /sup 201/Tl total-body scintigraphy is a useful procedure in follow-up of thyroid cancer, however, the combination of parameters provides the greatest reliability. In medullary thyroid carcinoma, which is usually /sup 131/I negative, /sup 201/Tl total-body scintigraphy can be of great value for the localization of metastases which are indicated by elevated serum levels of calcitonin and carcinoembryonic antigen.

  11. Delayed redistribution in thallium 201 SPECT myocardial perfusion studies

    SciTech Connect

    Ziessman, H.A.; Keyes, J.W. Jr.; Fox, L.M.; Green, C.E.; Fox, S.M. )

    1989-11-01

    Stress {sup 201}Tl myocardial perfusion studies are useful in differentiating viable, reversibly ischemic from infarcted myocardium. A perfusion defect that shows redistribution 2 to 4 h after {sup 201}Tl injection is diagnostic of ischemia, while a fixed defect suggests infarction. However, occasional patients with a fixed defect at 4 h have redistribution at 24 h. This study evaluates the frequency and significance of this delayed redistribution with SPECT {sup 201}Tl. Patients with either no or incomplete redistribution at 4 h had repeat imaging 18 to 48 h later. Delayed redistribution was seen in 8/26 (31 percent). Four had incomplete and four had no redistribution at 4 h. Delayed redistribution with SPECT {sup 201}Tl is more common than generally appreciated, and we recommend delayed images in patients with fixed perfusion defects or incomplete redistribution at 4-h imaging, particularly in patients with previous infarctions for whom a revascularization procedure is being considered.

  12. Sex-specific criteria for interpretation of thallium-201 myocardial uptake and washout studies

    SciTech Connect

    Rabinovitch, M.; Suissa, S.; Elstein, J.; Staniloff, H.; Tang, A.; Rush, C.; Aldis, A.; Tannous, R.; Turek, M.; Addas, A.

    1986-12-01

    A study was undertaken to determine the effect of gender on criteria for the quantitative analysis of exercise-redistribution /sup 201/Tl myocardial scintigraphy. The studies of 26 normal females and 23 normal males were subjected to bilinear interpolative background subtraction and horizontal profile analysis. Significant sexual differences were found in both regional uptake ratios and washout rates. These differences primarily reflected a proportionately decreased anterior and upper septal uptake in females, and faster washout in females. Faster myocardial /sup 201/Tl washout rates in females could not be clearly ascribed to either a physiological or artifactual explanation. It is concluded that since important differences exist between males and females in the detected pattern of /sup 201/Tl myocardial uptake and washout, sex-specific criteria may enhance the predictive accuracy of exercise-redistribution /sup 201/Tl myocardial scintigraphy.

  13. Observational Assessment of Preschool Disruptive Behavior, Part I: reliability of the Disruptive Behavior Diagnostic Observation Schedule (DB-DOS).

    PubMed

    Wakschlag, Lauren S; Hill, Carri; Carter, Alice S; Danis, Barbara; Egger, Helen L; Keenan, Kate; Leventhal, Bennett L; Cicchetti, Domenic; Maskowitz, Katie; Burns, James; Briggs-Gowan, Margaret J

    2008-06-01

    To examine the reliability of the Disruptive Behavior Diagnostic Observation Schedule (DB-DOS), a new observational method for assessing preschool disruptive behavior. The DB-DOS is a structured clinic-based assessment designed to elicit clinically salient behaviors relevant to the diagnosis of disruptive behavior in preschoolers. Child behavior is assessed in three interactional contexts that vary by partner (parent versus examiner) and level of support provided. Twenty-one disruptive behaviors are coded within two domains: problems in Behavioral Regulation and problems in Anger Modulation. A total of 364 referred and nonreferred preschoolers participated: interrater reliability and internal consistency were assessed on a primary sample (n = 335) and test-retest reliability was assessed in a separate sample (n = 29). The DB-DOS demonstrated good interrater and test-retest reliability. Confirmatory factor analysis demonstrated an excellent fit of the DB-DOS multidomain model of disruptive behavior. The DB-DOS is a reliable observational tool for clinic-based assessment of preschool disruptive behavior. This standardized assessment method holds promise for advancing developmentally sensitive characterization of preschool psychopathology.

  14. A Direct Method to Extract Transient Sub-Gap Density of State (DOS) Based on Dual Gate Pulse Spectroscopy.

    PubMed

    Dai, Mingzhi; Khan, Karim; Zhang, Shengnan; Jiang, Kemin; Zhang, Xingye; Wang, Weiliang; Liang, Lingyan; Cao, Hongtao; Wang, Pengjun; Wang, Peng; Miao, Lijing; Qin, Haiming; Jiang, Jun; Xue, Lixin; Chu, Junhao

    2016-06-14

    Sub-gap density of states (DOS) is a key parameter to impact the electrical characteristics of semiconductor materials-based transistors in integrated circuits. Previously, spectroscopy methodologies for DOS extractions include the static methods, temperature dependent spectroscopy and photonic spectroscopy. However, they might involve lots of assumptions, calculations, temperature or optical impacts into the intrinsic distribution of DOS along the bandgap of the materials. A direct and simpler method is developed to extract the DOS distribution from amorphous oxide-based thin-film transistors (TFTs) based on Dual gate pulse spectroscopy (GPS), introducing less extrinsic factors such as temperature and laborious numerical mathematical analysis than conventional methods. From this direct measurement, the sub-gap DOS distribution shows a peak value on the band-gap edge and in the order of 10(17)-10(21)/(cm(3)·eV), which is consistent with the previous results. The results could be described with the model involving both Gaussian and exponential components. This tool is useful as a diagnostics for the electrical properties of oxide materials and this study will benefit their modeling and improvement of the electrical properties and thus broaden their applications.

  15. A Direct Method to Extract Transient Sub-Gap Density of State (DOS) Based on Dual Gate Pulse Spectroscopy

    NASA Astrophysics Data System (ADS)

    Dai, Mingzhi; Khan, Karim; Zhang, Shengnan; Jiang, Kemin; Zhang, Xingye; Wang, Weiliang; Liang, Lingyan; Cao, Hongtao; Wang, Pengjun; Wang, Peng; Miao, Lijing; Qin, Haiming; Jiang, Jun; Xue, Lixin; Chu, Junhao

    2016-06-01

    Sub-gap density of states (DOS) is a key parameter to impact the electrical characteristics of semiconductor materials-based transistors in integrated circuits. Previously, spectroscopy methodologies for DOS extractions include the static methods, temperature dependent spectroscopy and photonic spectroscopy. However, they might involve lots of assumptions, calculations, temperature or optical impacts into the intrinsic distribution of DOS along the bandgap of the materials. A direct and simpler method is developed to extract the DOS distribution from amorphous oxide-based thin-film transistors (TFTs) based on Dual gate pulse spectroscopy (GPS), introducing less extrinsic factors such as temperature and laborious numerical mathematical analysis than conventional methods. From this direct measurement, the sub-gap DOS distribution shows a peak value on the band-gap edge and in the order of 1017-1021/(cm3·eV), which is consistent with the previous results. The results could be described with the model involving both Gaussian and exponential components. This tool is useful as a diagnostics for the electrical properties of oxide materials and this study will benefit their modeling and improvement of the electrical properties and thus broaden their applications.

  16. DOS-HEATING6: A general conduction code with nuclear heat generation derived from DOT-IV transport calculations

    SciTech Connect

    Williams, M.L.; Yuecel, A.; Nadkarny, S.

    1988-05-01

    The HEATING6 heat conduction code is modified to (a) read the multigroup particle fluxes from a two-dimensional DOT-IV neutron- photon transport calculation, (b) interpolate the fluxes from the DOT-IV variable (optional) mesh to the HEATING6 control volume mesh, and (c) fold the interpolated fluxes with kerma factors to obtain a nuclear heating source for the heat conduction equation. The modified HEATING6 is placed as a module in the ORNL discrete ordinates system (DOS), and has been renamed DOS-HEATING6. DOS-HEATING6 provides the capability for determining temperature distributions due to nuclear heating in complex, multi-dimensional systems. All of the original capabilities of HEATING6 are retained for the nuclear heating calculation; e.g., generalized boundary conditions (convective, radiative, finned, fixed temperature or heat flux), temperature and space dependent thermal properties, steady-state or transient analysis, general geometry description, etc. The numerical techniques used in the code are reviewed and the user input instructions and JCL to perform DOS-HEATING6 calculations are presented. Finally a sample problem involving coupled DOT-IV and DOS-HEATING6 calculations of a complex space-reactor configurations described, and the input and output of the calculations are listed. 10 refs., 11 figs., 6 tabs.

  17. A Direct Method to Extract Transient Sub-Gap Density of State (DOS) Based on Dual Gate Pulse Spectroscopy

    PubMed Central

    Dai, Mingzhi; Khan, Karim; Zhang, Shengnan; Jiang, Kemin; Zhang, Xingye; Wang, Weiliang; Liang, Lingyan; Cao, Hongtao; Wang, Pengjun; Wang, Peng; Miao, Lijing; Qin, Haiming; Jiang, Jun; Xue, Lixin; Chu, Junhao

    2016-01-01

    Sub-gap density of states (DOS) is a key parameter to impact the electrical characteristics of semiconductor materials-based transistors in integrated circuits. Previously, spectroscopy methodologies for DOS extractions include the static methods, temperature dependent spectroscopy and photonic spectroscopy. However, they might involve lots of assumptions, calculations, temperature or optical impacts into the intrinsic distribution of DOS along the bandgap of the materials. A direct and simpler method is developed to extract the DOS distribution from amorphous oxide-based thin-film transistors (TFTs) based on Dual gate pulse spectroscopy (GPS), introducing less extrinsic factors such as temperature and laborious numerical mathematical analysis than conventional methods. From this direct measurement, the sub-gap DOS distribution shows a peak value on the band-gap edge and in the order of 1017–1021/(cm3·eV), which is consistent with the previous results. The results could be described with the model involving both Gaussian and exponential components. This tool is useful as a diagnostics for the electrical properties of oxide materials and this study will benefit their modeling and improvement of the electrical properties and thus broaden their applications. PMID:27297030

  18. First-principle calculation of the electronic structure, DOS and effective mass TlInSe2

    NASA Astrophysics Data System (ADS)

    Ismayilova, N. A.; Orudzhev, G. S.; Jabarov, S. H.

    2017-05-01

    The electronic structure, density of states (DOS), effective mass are calculated for tetragonal TlInSe2 from first principle in the framework of density functional theory (DFT). The electronic structure of TlInSe2 has been investigated by Quantum Wise within GGA. The calculated band structure by Hartwigsen-Goedecker-Hutter (HGH) pseudopotentials (psp) shows both the valence band maximum and conduction band minimum located at the T point of the Brillouin zone. Valence band maximum at the T point and the surrounding parts originate mainly from 6s states of univalent Tl ions. Bottom of the conduction band is due to the contribution of 6p-states of Tl and 5s-states of In atoms. Calculated DOS effective mass for holes and electrons are mDOS h∗ = 0.830m e, mDOS h∗ = 0.492m e, respectively. Electron effective masses are fairly isotropic, while the hole effective masses show strong anisotropy. The calculated electronic structure, density of states and DOS effective masses of TlInSe2 are in good agreement with existing theoretical and experimental results.

  19. Thallium-201 uptake in lung cancer

    SciTech Connect

    Chin, B.B.; Zukerberg, B.W.; Buchpiguel, C.; Alavi, A.

    1995-08-01

    {sup 201}Tl imaging and {sup 99m}Tc-sestamibi have shown a high sensitivity in detecting lung and breast malignancies. Recent studies with delayed imaging have reported acceptable specificity compared to earlier reports. Further prospective studies are necessary to determine the role of various imaging modalities, including PET and single gamma emitters such as {sup 201}Tl, {sup 99m}Tc-sestamibi and radiolabeled somatostatin receptor agents in the management of patients with various malignancies. 52 refs., 4 figs.

  20. Diagnosis of segmental necrosis in a pancreas transplant by thallium-201 perfusion scintigraphy

    SciTech Connect

    Hirsch, H.; Fernandez-Ulloa, M.; Munda, R.; Fisher, R.A.; Moulton, J.S.; Huth, C.J. )

    1991-08-01

    Thallium-201 was used to image a patient with a pancreatic transplant. Incomplete visualization of the graft on the 201Tl scan, compared to CT, led to the diagnosis of segmental necrosis of the tail of the graft. Due to the low background and favorable target-to-non-target ratio, 201Tl pancreas scintigraphy may be useful in the follow-up of pancreatic transplants.

  1. The effects of chemical and radioactive properties of Tl-201 on human erythrocyte glucose 6-phosphate dehydrogenase activity.

    PubMed

    Sahin, Ali; Senturk, Murat; Ciftci, Mehmet; Varoglu, Erhan; Kufrevioglu, Omer Irfan

    2010-04-01

    The inhibitory effects of thallium-201 ((201)Tl) solution on human erythrocyte glucose 6-phosphate dehydrogenase (G6PD) activity were investigated. For this purpose, erythrocyte G6PD was initially purified 835-fold at a yield of 41.7% using 2',5'-Adenosine diphosphate sepharose 4B affinity gel chromatography. The purification was monitored by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, which showed a single band for the final enzyme preparation. The in vitro and in vivo effects of the (201)Tl solution including Tl(+), Fe(+3) and Cu(+2) metals and the in vitro effects of the radiation effect of the (201)Tl solution and non-radioactive Tl(+), Fe(+3) and Cu(+2) metals on human erythrocyte G6PD enzyme were studied. Enzyme activity was determined with the Beutler method at 340 nm using a spectrophotometer. All purification procedures were carried out at +4 degrees C. (201)Tl solution and radiation exposure had inhibitory effects on the enzyme activity. IC(50) value of (201)Tl solution was 36.86 microl ([Tl(+)]: 0.0036 microM, [Cu(+2)]: 0.0116 microM, [Fe(+3)]: 0.0132 microM), of human erythrocytes G6PD. Seven human patients were also used for in vivo studies of (201)Tl solution. Furthermore, non-radioactive Tl(+), Fe(+3) and Cu(+2) were found not to have influenced the enzyme in vitro. Human erythrocyte G6PD activity was inhibited by exposure for up to 10 minutes to 0.057 mCi/kg (201)Tl solution. It was detected in in vitro and in vivo studies that the human erythrocyte G6PD enzyme is inhibited due to the radiation effect of (201)Tl solution. Copyright 2010 Elsevier Inc. All rights reserved.

  2. Age and isotopic relationships among the angrites Lewis Cliff 86010 and Angra dos Reis

    NASA Technical Reports Server (NTRS)

    Lugmair, G. W.; Galer, S. J. G.

    1992-01-01

    The paper presents results of a wide-ranging isotopic investigation of the the Antarctic angrite LEW-86010 (LEW), and reassesses the type angrite Angra dos Reis (ADOR) in order to obtain precise radiometric ages and initial Sr isotopic compositions, and to search for the erstwhile presence of the short-lived nuclei Sm-146 and Al-26 via their daughter products. The isotopic compositions of Sm, U, Ca, and Ti were measured to allow a detailed appraisal to be made of the relations between, and the geneology of, these two angrites. LEW proves to be severely contaminated with modern terrestrial Pb, which is shown to result from terrestrial weathering. Concordant Pb-Pb model ages of pyroxene separates are obtained; uranium isotopic compositions are normal within error. Overall, striking age and isotopic similarities between LEW and ADOR were found, suggesting almost simultaneous production on the same asteroid, even though recent experimental studies imply that the two are not comagmatic.

  3. Estudio dinámico de un potencial perturbador dependiente de dos parámetros

    NASA Astrophysics Data System (ADS)

    Miloni, O.; Brunini, A.

    El objeto del presente trabajo consiste en el estudio dinámico de un sistema dinámico caracterizado por la función hamiltoniana correspondiente a un satélite planetario perturbado por la acción del Sol y del achatamiento del planeta madre. Cuando dicha Hamiltoniana se promedia respecto de los términos de corto período, esta queda con dos grados de libertad, y su estudio puede ser realizado con las herramientas clásicas de la dinámica no-lineal. Se tratará de determinar regiones regulares y caóticas de movimiento. En el caso de estas últimas, es de particular interés la determinación de su orígen.

  4. On securing wireless sensor network--novel authentication scheme against DOS attacks.

    PubMed

    Raja, K Nirmal; Beno, M Marsaline

    2014-10-01

    Wireless sensor networks are generally deployed for collecting data from various environments. Several applications specific sensor network cryptography algorithms have been proposed in research. However WSN's has many constrictions, including low computation capability, less memory, limited energy resources, vulnerability to physical capture, which enforce unique security challenges needs to make a lot of improvements. This paper presents a novel security mechanism and algorithm for wireless sensor network security and also an application of this algorithm. The proposed scheme is given to strong authentication against Denial of Service Attacks (DOS). The scheme is simulated using network simulator2 (NS2). Then this scheme is analyzed based on the network packet delivery ratio and found that throughput has improved.

  5. Age and isotopic relationships among the angrites Lewis Cliff 86010 and Angra dos Reis

    NASA Technical Reports Server (NTRS)

    Lugmair, G. W.; Galer, S. J. G.

    1992-01-01

    The paper presents results of a wide-ranging isotopic investigation of the the Antarctic angrite LEW-86010 (LEW), and reassesses the type angrite Angra dos Reis (ADOR) in order to obtain precise radiometric ages and initial Sr isotopic compositions, and to search for the erstwhile presence of the short-lived nuclei Sm-146 and Al-26 via their daughter products. The isotopic compositions of Sm, U, Ca, and Ti were measured to allow a detailed appraisal to be made of the relations between, and the geneology of, these two angrites. LEW proves to be severely contaminated with modern terrestrial Pb, which is shown to result from terrestrial weathering. Concordant Pb-Pb model ages of pyroxene separates are obtained; uranium isotopic compositions are normal within error. Overall, striking age and isotopic similarities between LEW and ADOR were found, suggesting almost simultaneous production on the same asteroid, even though recent experimental studies imply that the two are not comagmatic.

  6. Measured oxygen fugacities of the Angra dos Reis achondrite as a function of temperature

    USGS Publications Warehouse

    Brett, R.; Stephen, Huebner J.; Sato, M.

    1977-01-01

    Measurements of the oxygen fugacity (f{hook}O2) as a function of temperature (T) were made on an interior bulk sample of the cumulate achondrite, Angra dos Reis. Data clustered between the f{hook}O2-T relationship of the iron-wu??stite assemblage and 1.2 log atm units above iron-wu??stite. Interpretation of the data indicates that, throughout most of the cooling history of the meteorite, f{hook}O2 values were defined by equilibria involving iron-bearing species at values close to the f{hook}O2 of the assemblage iron-wu??stite. Measured f{hook}O2 data are compatible with crystallization and cooling at pressures greater than 50 bars. ?? 1977.

  7. Revisiting DoS Attacks and Privacy in RFID-Enabled Networks

    NASA Astrophysics Data System (ADS)

    D'Arco, Paolo; Scafuro, Alessandra; Visconti, Ivan

    Vaudenay presented in [ASIACRYPT 2007] a general RFID security and privacy model that abstracts some previous works in a single, concise, and much more understandable framework. He introduced eight distinct notions of privacy, corresponding to adversaries of different strength, and proved some possibility and impossibility results for such privacy notions. However, some interesting problems as: 1) achieving stronger privacy using low-cost tags (i.e., tags that usually can not perform public-key cryptography), 2) achieving stronger privacy in presence of side-channel attacks (e.g., DoS attacks, detection of the outputs of identification protocols), and 3) achieving stronger privacy under standard complexity-theoretic assumptions, are still left open.

  8. An MS-DOS-based program for analyzing plutonium gamma-ray spectra

    SciTech Connect

    Ruhter, W.D.; Buckley, W.M.

    1989-09-07

    A plutonium gamma-ray analysis system that operates on MS-DOS-based computers has been developed for the International Atomic Energy Agency (IAEA) to perform in-field analysis of plutonium gamma-ray spectra for plutonium isotopics. The program titled IAEAPU consists of three separate applications: a data-transfer application for transferring spectral data from a CICERO multichannel analyzer to a binary data file, a data-analysis application to analyze plutonium gamma-ray spectra, for plutonium isotopic ratios and weight percents of total plutonium, and a data-quality assurance application to check spectral data for proper data-acquisition setup and performance. Volume 3 contains the software listings for these applications.

  9. The Secret List of Dos and Don'ts for Filmmaking

    NASA Astrophysics Data System (ADS)

    Kramer, N.

    2012-12-01

    Science is a massive black box to billions of people who walk the streets. However, the process of filmmaking can be equally as mystifying. As with the development of many scientific experiments, the process starts on a napkin at a restaurant…but then what? The road to scientific publication is propelled by a canonical list of several dos and don't that fit most situations. An equally useful list exists for up-and-coming producers. The list streamlines efforts, optimizes your use of the tools at your fingertips and enhances impact. Many fundamentals can be learned from books, but during this talk we will project and discuss several examples of best practices, from honing a story, to identifying audience appeal, filming, editing and the secrets of inexpensively acquiring expert help. Whether your goal is a two-minute webisode or a 90 minute documentary, these time-tested practices, with a little awareness, can give life to your films.;

  10. [Anterior cruciate ligament-plasty using the "U-dos" technique].

    PubMed

    Morales-Trevizo, C; Paz-García, M; Leal-Berumen, I; Leal-Contreras, C; Berumen-Nafarrate, E

    2013-01-01

    The knee is a compound diarthrodial joint, vulnerable to serious injuries such as ligament injuries of: medial collateral ligament, lateral collateral ligament, anterior cruciate ligament and posterior cruciate ligament, as cruciate ligaments limit rotation movement in the joint. The purpose of our study was to create a new technique to treat injuries of the anterior cruciate ligament, which is composed of two bundles--anteromedial and posterolateral--trying to achieve an anatomical reconstruction that allows for a normal biomechanical recovery. This technique reduces the use of fixation material and costs. The diagnosis of anterior cruciate ligament injuries was made with the pivot shift test. There are currently two repair methods for anterior cruciate ligament injuries: single bundle or double bundle repair; none of these techniques is considered as the gold standard, as their results are very similar. This paper describes a technique used for the treatment of anterior cruciate ligament injuries, known as "U-dos", and its clinical results. Cross-sectional, observational study that enrolled 20 patients with total anterior cruciate ligament injuries who underwent anterior cruciate ligament plasty using the "U-dos" technique between June 2009 and June 2010. The technique requires the use of bone bank allograft, in this case of the anterior tibial ligament. Patients were assessed using the Lysholm scale and the pivot shift test. Our results show that all the pivot shift tests were negative and assessments according to the Lysholm scale were from normal to excellent in 95% of cases (19/20). Only one failure was reported, with avulsion of the graft attachment which required a surgical intervention.

  11. Thallium-201 scintigraphy for the assessment of long-term prognosis in patients with osteosarcoma.

    PubMed

    Inaki, Anri; Taki, Junichi; Wakabayashi, Hiroshi; Sumiya, Hisashi; Zen, Yoh; Tsuchiya, Hiroyuki; Kinuya, Seigo

    2012-08-01

    The aim of this study was to confirm the prognostic value of (201)Tl scintigraphy in the midcourse of preoperative chemotherapy in patients with osteosarcoma. The 28 patients with biopsy-proven osteosarcoma were enrolled retrospectively in this study. Planar scintigraphy was performed 15 min after injection of 111 MBq (201)Tl before preoperative chemotherapy and after third course (midcourse) of chemotherapy in all patients. The (201)Tl uptake ratio was calculated by dividing the count density of the lesion by that of the contralateral normal area. The percentage reduction of the (201)Tl uptake ratio calculated by 100 × [(pre-chemotherapy ratio - mid-chemotherapy ratio)/pre-chemotherapy ratio] was compared with the histopathological response and long-term survival rate. Good histopathological response was observed in 16 patients. Mean follow-up period was 58.0 ± 41 months. Both overall and event-free survival rates of histopathologically good responders were significantly higher than that of poor responders (P = 0.018 and P = 0.0076). There was also significant correlation between pre-chemotherapeutic effect evaluated with (201)Tl scintigraphy and overall and event-free survival rate in all patients (P = 0.045 and P = 0.017, respectively), and in patients without metastasis at initial diagnosis (P = 0.043 and P = 0.031, respectively). (201)Tl scintigraphy performed in the middle of neoadjuvant chemotherapy can predict overall survival and event-free survival in patients with osteosarcoma.

  12. Quantitative analysis of planar technetium-99m-sestamibi myocardial perfusion images using modified background subtraction

    SciTech Connect

    Koster, K.; Wackers, F.J.; Mattera, J.A.; Fetterman, R.C. )

    1990-08-01

    Standard interpolative background subtraction, as used for thallium-201 ({sup 201}Tl), may create artifacts when applied to planar technetium-99m-Sestamibi ({sup 99m}Tc-Sestamibi) images, apparently because of the oversubtraction of relatively high extra-cardiac activity. A modified background subtraction algorithm was developed and compared to standard background subtraction in 16 patients who had both exercise-delayed {sup 201}Tl and exercise-rest {sup 99m}Tc-Sestamibi imaging. Furthermore, a new normal data base was generated. Normal {sup 99m}Tc-Sestamibi distribution was slightly different compared to {sup 201}Tl. Using standard background subtraction, mean defect reversibility was significantly underestimated by {sup 99m}Tc-Sestamibi compared to {sup 201}Tl (2.8 +/- 4.9 versus -1.8 +/- 8.4, p less than 0.05). Using the modified background subtraction, mean defect reversibility on {sup 201}Tl and {sup 99m}Tc-Sestamibi images was comparable (2.8 +/- 4.9 versus 1.7 +/- 5.2, p = NS). We conclude, that for quantification of {sup 99m}Tc-Sestamibi images a new normal data base, as well as a modification of the interpolative background subtraction method should be employed to obtain quantitative results comparable to those with {sup 201}Tl.

  13. Thallium-201 diethyldithiocarbamate: an alternative to iodine-123 N-isopropyl-p-iodoamphetamine

    SciTech Connect

    de Bruine, J.F.; van Royen, E.A.; Vyth, A.; de Jong, J.M.B.V.; van der Schoot, J.B.

    1985-08-01

    The study of cerebral blood flow by single photon emission computed tomography (SPECT) requires lipophilic radiopharmaceuticals. The high cost and limited availability of N-isopropyl-p-(I-123)-iodoamphetamine ((/sup 123/I)IMP) led the authors to search for alternatives. Following the recent development of thallium-201 diethyldithiocarbamate ((/sup 201/Tl)DDC), the authors have compared the brain uptake of (/sup 123/I)IMP and (/sup 201/Tl)DDC in rabbits. The (/sup 201/Tl)DDC uptake was more instantaneous than that of (/sup 123/I)IMP. The ratios of gray to white matter distribution were about equal. In brain macroautoradiography (/sup 201/Tl)DDC yielded images of good quality with excellent demarcation of gray and white matter, persisting for at least 45 min after injection. They conclude that (/sup 123/I)IMP and (/sup 201/Tl)DDC are equally suitable for blood flow study of the rabbit brain. The first human tomographic results obtained in two healthy volunteers demonstrate that clinical application of SPECT (/sup 201/Tl)DDC may be feasible.

  14. The effects of chemical and radioactive properties of Tl-201 on human erythrocyte glutathione reductase activity.

    PubMed

    Sahin, Ali; Senturk, Murat; Akkemik, Ebru; Ciftci, Mehmet

    2012-01-01

    The aim of the study was to evaluate the inhibitory effects of thallium-201 ((201)Tl) solution on human erythrocyte glutathione reductase (GR) activity. Erythrocyte GR was initially purified by 2',5'-adenosine diphosphate Sepharose-4B affinity and Sephadex G-200 gel filtration chromatography. The purification was monitored by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, which showed a single band for the final enzyme preparation. The in vitro and in vivo effects of the (201)Tl solution including Tl(+), Fe(+3) and Cu(+2) metals and the in vitro effects of the radiation effect of the (201)Tl solution and nonradioactive Tl(+), Fe(+3) and Cu(+2) metals on human erythrocyte GR enzyme were studied. Enzyme activity was determined with the Beutler method at 340 nm using a spectrophotometer. All purification procedures were carried out at (+)4 °C. Glutathione reductase was purified 2033-fold at a yield of 28.17%. (201)Tl solution and radiation exposure had inhibitory effects on the enzyme activity. Besides, effects of nonradioactive Tl(+), Fe(+3) and Cu(+2) were studied on enzyme activity in vitro. Furthermore, seven human patients were also used for in vivo studies of (201)Tl solution. It was detected in in vitro and in vivo studies that the human erythrocyte GR enzyme is inhibited due to the radiation effect of (201)Tl solution. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Creating a Global Fiducials Program (GFP) Site: Lago Cachet Dos example in Chile

    NASA Astrophysics Data System (ADS)

    Friesen, B. A.; Nimick, D. A.; Wilson, E. M.

    2012-12-01

    The USGS has been acquiring remotely sensed imagery from all over the world, collecting thousands of images at more than 200 sites, and creating Literal Image Derived Products (LIDPs) as part of the Global Fiducials Program (GFP). The GFP program enables scientists to use these images to study our rapidly changing planet at carefully selected locations around the world. New GFP Sites are created and added each year. Researchers at the University of Alaska, for instance, added areas susceptible to coastal erosion for monitoring the long-term effects of high tides and storms. This presentation will guide you through the process of creating a new GFP site for your area of interest. We will describe the components of the GFP and its archive, the Global Fiducials Library. The Global Fiducials Program—Initial Site Proposal form will be presented and we will show you how to complete each component in order to propose a new site. Lago Cachet Dos, a glacier-dammed lake in southern Chile, is currently being proposed as a new GFP site and will be used as the example for this exercise. In addition, USGS web sites will be used to illustrate how a long-term imagery record can tell a story and to demonstrate viewing and downloading the type of data that will be available online and free of charge through the GFP.

  16. A proposed application of an industrial DOS computer for distribution substation monitoring and control

    SciTech Connect

    Batur, I. . Aselsan Military); Guven, A.N.; Ozay, N. . Electrical Engineering Dept.)

    1994-04-01

    This paper presents the design and implementation of an intelligent controller intended for use in distribution substations to perform monitoring and control duties within the framework of distribution automation needs. The hardware of the developed controller is a DOS based industrial computer running on ECB-BUS. The application software handles all input/output tasks, data collection, manipulation and control decisions with its flexible structure. This embedded controller measures bus voltage, transformer and feeder currents and calculates the real and reactive power, power factor, frequency, and total harmonic distortion of voltage and current. In addition to its local and remote data acquisition and monitoring functions by means of console and SCADA outputs, the system, through its relay outputs, is capable of performing automation tasks such as integrated Volt/Var control, overload and underfrequency detection and load shedding at the substation level. This reliable, high capacity and low cost system is completely programmable so that it can handle new requirements with new configurations easily.

  17. Environmental discrimination among soft-bottom mollusc associations off Lagoa dos Patos, South Brazil

    NASA Astrophysics Data System (ADS)

    Absalão, R. S.

    1991-01-01

    Sublittoral benthic molluscs established in the outlet of Lagoa dos Patos (South Brazil) were sampled with a rectangular dredge and the malacological associations delineated by cluster analysis (WPGA) using the Baroni-Urbani and Buser similarity index. Three main associations were characterized in bands parallel to the beach with relative concordance with specific sedimentological facies. The multiple discriminant analysis showed that there was a high correlation between these associations and the following environmental parameters: depth, average grain size, skewness of the sediment, medium sand, coarse sand, total sand and total mud. The effect of reducing the multidimensionality of the data to two factors, ecologically explained, brings out the importance of depth, average grain size, total sand and total mud. The first appears to be a bathymetric gradient of stability/disturbance; the disturbance from storms becomes less frequent with increasing depth. This is partially supported by the results of the Caswell neutral model, and is in agreement with the intermediate disturbance hypothesis predictions. The second sedimentological factor is the relative percentages of sand and mud in determining the specific composition of these associations.

  18. Endocrine disruptors in water filters used in the Rio dos Sinos Basin region, Southern Brazil.

    PubMed

    Furtado, C M; von Mühlen, C

    2015-05-01

    The activated carbon filter is used in residences as another step in the treatment of drinking water, based on a physical-chemical process to absorb pollutants that are not removed in conventional treatment. Endocrine disruptors (EDCs) are exogenous substances or mixtures of substances that acts on the endocrine system similarly to the endogenously produced hormones, triggering malfunctions and harmful changes to human and animal health. The objective of the present work was to study EDCs through semi-quantitative analysis of residential water filters collected in the region of Rio dos Sinos basin, focusing on two specific classes: hormones and phenols. The solid phase extraction principle was used for the extraction of compounds and gas chromatography coupled with mass spectrometry for the separation and characterization of EDCs. Four samples of residential filters collected from public water distribution and artesian wells, from the cities of Novo Hamburgo and São Leopoldo were analysed. Using the developed methodology, it was possible to detect and comparatively quantify selected EDCs in all studied samples, which indicates the presence of these contaminants in drinking water from different sources.

  19. Urano y sus dos satélites irregulares recientemente descubiertos

    NASA Astrophysics Data System (ADS)

    Parisi, M. G.; Brunini, A.

    Hasta hace poco tiempo, Urano era el único de los Planetas Gigantes que no poseía satélites irregulares. Esto lo diferenciaba del resto de los planetas Gigantes, al igual que la peculiar oblicuidad de su eje de spin. La gran inclinación de su eje de rotación se debe probablemente a una colisión que sufrió el planeta con otro embrión planetario al final del proceso de formación. Esta colisión habría desligado satélites exteriores preexistentes del planeta. Recientemente se han descubierto dos satélites irregulares de Urano, lo que introduce algunas nuevas cotas y condiciones en el escenario de la "Hipótesis de la Gran Colisión" . Los satélites irregulares de Urano tuvieron que ser capturados en una etapa posterior a la del escenario de la Gran Colisión, de no ser así, hubieran sido eyectados del sistema por el impulso impartido con ese gran impacto. En este trabajo, se discuten los posibles mecanismos de captura de los satélites irregulares y se presenta un nuevo posible mecanismo para dicha captura.

  20. Dos and don'ts for using climate information for water resource planning and management

    NASA Astrophysics Data System (ADS)

    Vano, J. A.; Clark, M. P.; Nijssen, B.; Wood, A.; Gutmann, E. D.; Arnold, J.

    2016-12-01

    Increasingly water managers and planners are being required to incorporate climate change information into their planning processes. This is generally seen as a step in the right direction. However, the continuously evolving and expanding realm of climate information can be confusing to use and easy to apply in ways the information producers never intended, and often in ways those producers might say are not viable. Additionally, advice on how various products should be used is not usually straightforward - it may require an extended dialogue between scientists and end users, which is not always feasible with current resources. While rarely is there a one-size fits all approach, there are usually preferable paths forward. To help the water resource planning and management community navigate the ever-changing climate science landscape, we present a set of guidelines for better practices when using climate information. These are divided into two categories: (1) process-based recommendations for developing an effective approach for using climate change scenarios, and (2) product-based cautions for using climate change information. This collection of dos and don'ts provides context on why certain strategies are preferable, including real-world examples. This work is intended to provide a foundation that can be built on through dialogue within and between the climate science and application communities to increase the usefulness of climate information.

  1. Geochemical and isotopic constraints on the tectonic setting of Serra dos Carajas belt, eastern Para, Brazil

    NASA Technical Reports Server (NTRS)

    Olszewski, W. J., Jr.; Gibbs, A. K.; Wirth, K. R.

    1986-01-01

    The lower part of the Serra dos Carajas belt is the metavolcanic and metasedimentary Grao para Group (GPG). The GPG is thought to unconformably overlie the older (but undated) Xingu Complex, composed of medium and high-grade gneisses and amphibolite and greenstone belts. The geochemical data indicate that the GPG has many features in common with ancient and modern volcanic suites erupted through continental crust. The mafic rocks clearly differ from those of most Archean greenstone belts, and modern MORB, IAB, and hot-spot basalts. The geological, geochemical, and isotopic data are all consistent with deposition on continental crust, presumably in a marine basin formed by crustal extension. The isotopic data also suggest the existence of depleted mantle as a source for the parent magmas of the GPG. The overall results suggest a tectonic environment, igneous sources, and petrogenesis similar to many modern continental extensional basins, in contrast to most Archean greenstone belts. The Hammersley basin in Australia and the circum-Superior belts in Canada may be suitable Archean and Proterozoic analogues, respectively.

  2. ANALYSIS OF THE PICO DOS DIAS SURVEY HERBIG Ae/Be CANDIDATES

    SciTech Connect

    Sartori, Marilia J.; Rodrigues, Claudia V.; Batalha, Celso

    2010-01-15

    A large sample of Herbig Ae/Be (HAeBe) candidates, distributed in different Galactic regions south to declination +30 deg., were identified by the Pico dos Dias Survey (a search for young stellar objects based on IRAS colors). Most of the candidates are nearby or associated with star-forming clouds, but several others are considered isolated objects. Aiming to verify the young nature of 93 HAeBe candidates, we searched for additional information that could be useful to confirm if they are pre-main-sequence (PMS) stars or evolved objects, which coincidentally show similar IRAS colors. By adopting a spectral index that is related to the amount of infrared excess and the shape of the spectral energy distribution, we have classified the sample according to three groups, which are analyzed on the basis of (1) circumstellar luminosity; (2) spatial distribution; (3) optical polarization; (4) near-infrared colors; (5) stellar parameters (mass, age, effective temperature); and (5) intensity of emission lines. Our analysis indicates that only 76% of the studied sample, mainly the group with intermediate to low levels of circumstellar emission, can be more confidently considered PMS stars. The nature of the remaining stars, which are in the other group that contains the highest levels of infrared excess, remains to be confirmed. They share the same characteristics of evolved objects, requiring complementary studies in order to correctly classify them. At least seven objects show characteristics typical of post-asymptotic giant branch or proto-planetary nebulae.

  3. 48 CFR 653.219-70 - DOS form DS-1910, Small Business Agency Review-Actions Above the Simplified Acquisition Threshold.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false DOS form DS-1910, Small... 653.219-70 DOS form DS-1910, Small Business Agency Review—Actions Above the Simplified Acquisition Threshold. As prescribed in 619.501(c), DS-1910 is prescribed for use in documenting set-aside decisions. ...

  4. Cross-Reactive Immunity to Mycobacterium tuberculosis DosR Regulon-Encoded Antigens in Individuals Infected with Environmental, Nontuberculous Mycobacteria▿ †

    PubMed Central

    Lin, May Young; Reddy, T. B. K.; Arend, Sandra M.; Friggen, Annemieke H.; Franken, Kees L. M. C.; van Meijgaarden, Krista E.; Verduyn, Marleen J. C.; Schoolnik, Gary K.; Klein, Michel R.; Ottenhoff, Tom H. M.

    2009-01-01

    Mycobacterium tuberculosis DosR regulon-encoded antigens are highly immunogenic in M. tuberculosis-infected humans and are associated with latent tuberculosis infection. We have investigated the hypothesis that infection with or exposure to nontuberculous mycobacteria (NTM) can induce cross-reactive immunity to M. tuberculosis DosR regulon-encoded antigens since responsiveness has been observed in non-M. tuberculosis-exposed but purified protein derivative-responsive individuals. M. tuberculosis DosR regulon-encoded antigen-specific T-cell responses were studied in peripheral blood mononuclear cells (PBMCs) of NTM-infected/exposed individuals. BLASTP was used to determine the presence of M. tuberculosis DosR regulon-encoded protein orthologs among environmental mycobacteria and nonmycobacteria. Significant gamma interferon production was observed in PBMCs from NTM-infected/exposed individuals in response to M. tuberculosis DosR regulon-encoded antigens. DosR regulon-encoded protein orthologs were prominently present in tuberculous and environmental mycobacteria and surprisingly also in nonmycobacteria. The ubiquitous presence of the highly conserved DosR master regulator protein Rv3133c suggests that this is a general adaptive bacterial response regulator. We report a first series of M. tuberculosis antigens to which cross-reactive immunity is induced by NTM infection/exposure. The high conservation of M. tuberculosis DosR regulon-encoded antigens most likely enables them to induce cross-reactive T-cell responses. PMID:19737909

  5. Lessons Learned from Sleep Education in Schools: A Review of Dos and Don'ts

    PubMed Central

    Blunden, Sarah; Rigney, Gabrielle

    2015-01-01

    Study Objectives: Sleep duration and quality are associated with negative neuropsychological and psychosocial outcomes in children and adolescents. However, community awareness of this is low and sleep education programs in schools are attempting to address this issue. Several studies now exist assessing the efficacy of these sleep education programs for improving sleep knowledge, sleep hygiene and sleep patterns. This paper presents these sleep education programs, most particularly, it presents the strengths and weaknesses of the current available studies in the hope that this can identify areas where future sleep education programs can improve. Methods: A systematic search of all school-based sleep education studies in adolescents was undertaken. Studies were scrutinized for author, teacher and participant comment regarding strengths and limitations of each study, which were then extracted and summarized. Results: Two specific types of sleep education programs emerged from the review, those that sought to change sleep behavior and those that sought simply to disseminate information. Issues that dictated the strength or weakness of a particular study including who delivers the program, the theoretical basis, the tools utilized to measure sleep patterns, the content, and their capacity to engage students were assessed. Sleep education was considered important by teachers, students and parents alike. Conclusions: Future sleep education programs need to take into account lessons learned from previous sleep education efforts in order to maximize the potential for sleep education programs to improve the sleep health of our young people. Commentary: A commentary on this article appears in this issue on page 595. Citation: Blunden S, Rigney G. Lessons learned from sleep education in schools: a review of dos and don'ts. J Clin Sleep Med 2015;11(6):671–680. PMID:25766709

  6. Las dos cosas: an analysis of attitudes of latina women on non-exclusive breastfeeding.

    PubMed

    Bartick, Melissa; Reyes, Catherine

    2012-02-01

    Non-exclusive breastfeeding among Latina women is commonly seen in the newborn period. The reasons behind las dos cosas ("both things") are not well understood but have included the beliefs that formula has vitamins and that adding formula will result in a chubbier baby, which is desirable. Many previous studies involved Mexican and Puerto Rican women living in the mainland United States. We performed detailed semistructured interviews with 17 Latina mothers in late pregnancy or the newborn period at a community hospital and an affiliated clinic in Massachusetts, serving a large Dominican population. Women were asked about their beliefs about breastfeeding, colostrum, and infant formula. Transcripts were analyzed using Nvivo 9 software (QSR International Pty. Ltd., Melbourne, Australia) to identify the frequencies of common trends. The most common reasons for introducing formula were treatment for insufficient milk, to keep the baby fuller longer, and planning for return to work. None of the women understood the potential risks of introducing formula on the establishment of breastfeeding, particularly on milk supply. Many thought that even limited amounts of breastfeeding were sufficient to produce a healthier child, failing to understand a negative dose-response effect of formula on health and milk production. While every woman saw breastfeeding as healthier, only one saw formula as unhealthy, an important distinction. None of the women expressed familiarity with medical recommendations around breastfeeding duration or exclusivity, with many believing that breastmilk alone would be insufficient to satisfy the hunger or nutritional needs of a growing child after as little as 3 months. Women consistently demonstrated a willingness to learn from health professionals. In counseling Latina women, it may be important to discuss the risks of formula to infant health, breastfeeding, and milk supply and to include the medical recommendations for breastfeeding exclusivity

  7. Implementation of DoS attack and mitigation strategies in IEEE 802.11b/g WLAN

    NASA Astrophysics Data System (ADS)

    Deng, Julia; Meng, Ke; Xiao, Yang; Xu, Roger

    2010-04-01

    IEEE 802.11 wireless Local Area Network (WLAN) becomes very prevalent nowadays. Either as a simple range extender for a home wired Ethernet interface, or as a wireless deployment throughout an enterprise, WLAN provides mobility, convenience, and low cost. However, an IEEE 802.11b/g wireless network uses the frequency of unlicensed 2.4GHz, which makes the network unsafe and more vulnerable than traditional Ethernet networks. As a result, anyone who is familiar with wireless network may initiate a Denial of Service (DoS) attack to influence the common communication of the network or even make it crash. In this paper, we present our studies on the DoS attacks and mitigation strategies for IEEE 802.11b/g WLANs and describe some initial implementations using IEEE 802.11b/g wireless devices.

  8. Video movie making using remote procedure calls and 4BSD Unix sockets on Unix, UNICOS, and MS-DOS systems

    SciTech Connect

    Robertson, D.W.; Johnston, W.E.; Hall, D.E.; Rosenblum, M.

    1990-03-01

    We describe the use of the Sun Remote Procedure Call and Unix socket interprocess communication mechanisms to provide the network transport for a distributed, client-server based, image handling system. Clients run under Unix or UNICOS and servers run under Unix or MS-DOS. The use of remote procedure calls across local or wide-area networks to make video movies is addressed.

  9. Diverted organic synthesis (DOS): accessing a new, natural product inspired, neurotrophically active scaffold through an intramolecular Pauson-Khand reaction.

    PubMed

    Mehta, Goverdhan; Samineni, Ramesh; Srihari, Pabbaraja; Reddy, R Gajendra; Chakravarty, Sumana

    2012-09-14

    Drawing inspiration from the impressive neurotrophic activity exhibited by the natural product paecilomycine A, we have designed a new natural product-like scaffold employing an intramolecular Pauson-Khand reaction. Several compounds based on the new designer scaffold exhibited promising neurotrophic activity and are worthy of further biological evaluation. Our findings also highlight the importance of a DOS strategy in creating useful therapeutical leads.

  10. Análise dos Conceitos Astronômicos Apresentados por Professores de Algumas Escolas Estaduais Brasileiras

    NASA Astrophysics Data System (ADS)

    Voelzke, Marcos Rincon; Gonzaga, Edson Pereira

    2011-12-01

    A razão para o desenvolvimento deste trabalho baseia-se no fato de que muitos professores da Educação Básica (EB) não lidam com conceitos relacionados à astronomia, e quando o fazem eles simplesmente seguem livros didáticos que podem conter erros conceituais. Como é de conhecimento geral a astronomia é um dos conteúdos a serem ensinados na EB fazendo parte dos Parâmetros Curriculares Nacionais e das Propostas Curriculares do Estado de São Paulo, mas é um fato, que vários pesquisadores apontam, a existência de muitos problemas no ensino da astronomia. Com o propósito de minimizar algumas dessas deficiências foi realizado um trabalho de pesquisa com a utilização de questionários pré e pós pesquisa, para tanto foi desenvolvido um Curso de Extensão Universitária para professores da Diretoria de Ensino Regional (DE) que abrange Mauá, Ribeirão Pires e Rio Grande da Serra (no Estado de São Paulo) com os seguintes objetivos: levantar concepções alternativas; subsidiar os professores por meio de palestras, debates e workshops, e verificar o sucesso da aprendizagem após o curso, adotando-se como referência, para a análise dos resultados, os dicionários de Língua Portuguesa (FERREIRA, 2004) e Enciclopédico de Astronomia e Astronáutica (MOURĀO, 1995). Portanto, dezesseis questões foram aplicadas antes e após o curso, assim pode-se verificar após a pesquisa que 100,0% dos professores sabiam os nomes das fases da Lua, 97,0% entenderam que o Sistema Solar é composto por oito planetas, 78,1% foram capazes de explicar como ocorre um eclipse lunar, um eclipse solar e um solstício, 72,7% sabiam como explicar a ocorrência das estações do ano; 64,5% explicaram corretamente a ocorrência do equinócio, 89,7% foram capazes de definir adequadamente o termo cometa; 63,6% definiram asteróide, 54,5% meteoro, 58,1% galáxia, e 42,4% planeta. Os resultados obtidos indicam uma aprendizagem significativa por parte dos participantes.

  11. Research on a Denial of Service (DoS) Detection System Based on Global Interdependent Behaviors in a Sensor Network Environment

    PubMed Central

    Song, Jae-gu; Jung, Sungmo; Kim, Jong Hyun; Seo, Dong Il; Kim, Seoksoo

    2010-01-01

    This research suggests a Denial of Service (DoS) detection method based on the collection of interdependent behavior data in a sensor network environment. In order to collect the interdependent behavior data, we use a base station to analyze traffic and behaviors among nodes and introduce methods of detecting changes in the environment with precursor symptoms. The study presents a DoS Detection System based on Global Interdependent Behaviors and shows the result of detecting a sensor carrying out DoS attacks through the test-bed. PMID:22163475

  12. Usefulness of thallium-201 SPECT for prediction of early progression in low-grade astrocytomas diagnosed by stereotactic biopsy.

    PubMed

    Park, Kyung-Jae; Kang, Shin-Hyuk; Park, Dong-Hyuk; Cho, Tai-Hyoung; Choe, Jae Gol; Chung, Yong-Gu

    2012-04-01

    To establish the value of thallium-201 single-photon emission computed tomography ((201)Tl-SPECT) as a predictor of early progression in low-grade astrocytomas (LGAs). We studied 57 consecutive patients who underwent 201 Tl-SPECT before stereotactic biopsy (n=33) or surgical resection (n=24). The value of radiologic and histopathological variables ((201)Tl index and MIB-1 index) in predicting progression free survival (PFS) was examined in each group of patients. During a median follow up of 55 months (range, 11-101), progression of the primary lesion was identified in 46 patients (80.7%). Based on Cox's proportional hazards model, the increased thallium uptake was associated with a short PFS in both biopsy and resection groups, whereas the MIB-1 index was significant only in the resection group. Considering the cut-off value, (201)Tl index>1.7 was statistically significant for reduced PFS in the biopsy group; however, MIB-1 index was not directly related to the PFS at any level. For the surgical resection group, both a (201)Tl index>1.9 and a MIB-1 index>6% were associated with short PFS. (201)Tl SPECT may play a role in prediction of early tumor progression not only in resected LGAs, but also in biopsy-proven LGAs. Therefore, we suggest that patients with LGAs established from biopsy should be considered as high-risk groups for early progression if the tumor shows a high (201)Tl uptake, even if the tumor demonstrates low proliferative activity on histopathologic examination. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Kinetic analysis of 18F-fluorodihydrorotenone as a deposited myocardial flow tracer: Comparison to thallium-201.

    SciTech Connect

    Marshall, Robert C.; Powers-Risius, Patricia; Reutter, Bryan W.; O'Neil, James P.; La Belle, Michael; Huesman, Ronald H.; VanBrocklin, Henry F.

    2004-03-01

    The goal of this investigation was to assess the accuracy of 18F-fluorodihydrorotenone (18F-FDHR) as a new deposited myocardial flow tracer and compare the results to those for 201Tl. Methods. The kinetics of these flow tracers were evaluated in 22 isolated, erythrocyte- and albumin-perfused rabbit hearts over a flow range encountered in patients. The two flow tracers plus a vascular reference tracer (131I-albumin) were introduced as a bolus through a port just above the aortic cannula. Myocardial extraction, retention, washout, and uptake parameters were computed from the venous outflow curves using the multiple indicator dilution technique and spectral analysis. Results. The mean initial extraction fractions of 18F-FDHR (0.85 +- 0.07) and 201Tl (0.87 +- 0.05) were not significantly different, although the initial extraction fraction for 18F-FDHR declined with flow (P < 0.0001), whereas the initial extraction fraction of 201Tl did not. Washout of 201Tl was faster (P < 0.001) and more affected by flow (P < 0.05) than 18F-FDHR washout. Except for initial extraction fraction, 18F-FDHR retention was greater (P < 0.001) and less affected by flow (P < 0.05) than 201Tl retention. Reflecting its superior retention, net uptake of 18F-FDHR was better correlated with flow than 201Tl uptake at both one and fifteen minutes after tracer introduction (P < 0.0001 for both comparisons). Conclusion. The superior correlation of 18F-FDHR uptake with flow indicates that it is a better flow tracer than 201Tl in the isolated rabbit heart. Compared to the other currently available positron-emitting flow tracers (82Rb, 13N-ammonia, and 15O-water), 18F-FDHR has the potential of providing excellent image resolution without the need for an on-site cyclotron.

  14. 32 CFR Appendix C to Part 197 - Procedures for the Department of State (DoS) Foreign Relations of the United States (FRUS) Series

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the DoS for the FRUS series under Public Law No. 102-138. b. Request authorization from the CIA, NSC.... Submit to the respective Agency a list of CIA and NSC documents copied and released to the...

  15. 32 CFR Appendix C to Part 197 - Procedures for the Department of State (DoS) Foreign Relations of the United States (FRUS) Series

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the DoS for the FRUS series under Public Law No. 102-138. b. Request authorization from the CIA, NSC.... Submit to the respective Agency a list of CIA and NSC documents copied and released to the...

  16. 32 CFR Appendix C to Part 197 - Procedures for the Department of State (DoS) Foreign Relations of the United States (FRUS) Series

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the DoS for the FRUS series under Public Law No. 102-138. b. Request authorization from the CIA, NSC.... Submit to the respective Agency a list of CIA and NSC documents copied and released to the...

  17. 32 CFR Appendix C to Part 197 - Procedures for the Department of State (DoS) Foreign Relations of the United States (FRUS) Series

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the DoS for the FRUS series under Public Law No. 102-138. b. Request authorization from the CIA, NSC.... Submit to the respective Agency a list of CIA and NSC documents copied and released to the...

  18. 32 CFR Appendix C to Part 197 - Procedures for the Department of State (DoS) Foreign Relations of the United States (FRUS) Series

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the DoS for the FRUS series under Public Law No. 102-138. b. Request authorization from the CIA, NSC.... Submit to the respective Agency a list of CIA and NSC documents copied and released to the...

  19. Ada Compiler Validation Summary Report: Certificate Number: 900125N1. 10258, R. R. Software, Inc., Janus/Ada 2.1.3 386 to DOS Bell 386 Under Ms-Dos 4 Host

    DTIC Science & Technology

    1990-01-25

    Ada Validation Vabkdim Swmy Re t AVF-VSR-90502/69 R R Softmm Im 3MW/Ada 21.3 316 to DOS chaplerl - Page I of 5 INTRODUCTION Organization ( AVO ). On...1.2 USE OF THIS VALIDATION SUMMARY REPORT Consistent with the national laws of the originating country, the AVO may make full and free public...contained in the Ada Compiler Validation Procedures and Guidelines. AVO The Ada Validation Organization. The AVO has oversight authority over all AVF

  20. Whole of Government Approach: Maximizing Unity of Effort Between the Department of Defense (DOD), Department of State (DOS), and the United States Agency for International Development (USAID)

    DTIC Science & Technology

    2013-12-13

    WHOLE OF GOVERNMENT APPROACH: MAXIMIZING UNITY OF EFFORT BETWEEN THE DEPARTMENT OF DEFENSE (DOD), DEPARTMENT OF STATE (DOS), AND THE...UNITED STATES AGENCY FOR INTERNATIONAL DEVELOPMENT (USAID) A thesis presented to the Faculty of the U.S. Army Command and General Staff...Government Approach: Maximizing Unity of Effort between the Department of Defense (DoD), Department of State (DoS), and the United States Agency for

  1. The FG loop of a heme-based gas sensor enzyme, Ec DOS, functions in heme binding, autoxidation and catalysis.

    PubMed

    Ito, Shinya; Igarashi, Jotaro; Shimizu, Toru

    2009-10-01

    Ec DOS is a heme-based gas sensor enzyme that catalyzes conversion from cyclic-di-GMP to linear-di-GMP in response to gas molecules, such as oxygen, CO and NO. Ec DOS contains an N-terminal heme-binding PAS domain and C-terminal phosphodiesterase domain. Based on crystal structures of the isolated heme-binding domain, it is suggested that the FG loop is involved in intra-molecular signal transduction to the catalytic domain. We generated nine full-length proteins mutated at ionic and non-ionic polar residues between positions 83 and 96 corresponding to the F-helix and FG loop, and examined the heme binding properties, autoxidation rates, and catalytic activities of mutant proteins. N84A and R85A mutant proteins displayed lower heme binding affinities, consistent with the finding that Asn84 interacts with propionate of protoporphyrin IX, and Arg85 with Asp40 on the heme proximal side. Autoxidation rates (0.058-0.54 min(-1)) of R91A, S96A and K89A/R91A/E93A mutant proteins were significantly higher than that (0.0053 min(-1)) of wild-type protein, suggesting that these residues in the FG loop form heme distal architecture conferring stability to the Fe(II)-O(2) complex. Catalytic activities of N84A and R85A mutant proteins with low heme affinity were significantly higher than those of wild-type protein in the absence of gas molecules. Accordingly, we propose that loss of heme binding enhances basal catalysis without the gas molecule, consistent with previous reports on heme inhibition of Ec DOS catalysis.

  2. Expression, maturation and turnover of DrrS, an unusually stable, DosR regulated small RNA in Mycobacterium tuberculosis

    PubMed Central

    Moores, Alexandra; Riesco, Ana B.; Schwenk, Stefan

    2017-01-01

    Mycobacterium tuberculosis depends on the ability to adjust to stresses encountered in a range of host environments, adjustments that require significant changes in gene expression. Small RNAs (sRNAs) play an important role as post-transcriptional regulators of prokaryotic gene expression, where they are associated with stress responses and, in the case of pathogens, adaptation to the host environment. In spite of this, the understanding of M. tuberculosis RNA biology remains limited. Here we have used a DosR-associated sRNA as an example to investigate multiple aspects of mycobacterial RNA biology that are likely to apply to other M. tuberculosis sRNAs and mRNAs. We have found that accumulation of this particular sRNA is slow but robust as cells enter stationary phase. Using reporter gene assays, we find that the sRNA core promoter is activated by DosR, and we have renamed the sRNA DrrS for DosR Regulated sRNA. Moreover, we show that DrrS is transcribed as a longer precursor, DrrS+, which is rapidly processed to the mature and highly stable DrrS. We characterise, for the first time in mycobacteria, an RNA structural determinant involved in this extraordinary stability and we show how the addition of a few nucleotides can lead to acute destabilisation. Finally, we show how this RNA element can enhance expression of a heterologous gene. Thus, the element, as well as its destabilising derivatives may be employed to post-transcriptionally regulate gene expression in mycobacteria in combination with different promoter variants. Moreover, our findings will facilitate further investigations into the severely understudied topic of mycobacterial RNA biology and into the role that regulatory RNA plays in M. tuberculosis pathogenesis. PMID:28323872

  3. Expression, maturation and turnover of DrrS, an unusually stable, DosR regulated small RNA in Mycobacterium tuberculosis.

    PubMed

    Moores, Alexandra; Riesco, Ana B; Schwenk, Stefan; Arnvig, Kristine B

    2017-01-01

    Mycobacterium tuberculosis depends on the ability to adjust to stresses encountered in a range of host environments, adjustments that require significant changes in gene expression. Small RNAs (sRNAs) play an important role as post-transcriptional regulators of prokaryotic gene expression, where they are associated with stress responses and, in the case of pathogens, adaptation to the host environment. In spite of this, the understanding of M. tuberculosis RNA biology remains limited. Here we have used a DosR-associated sRNA as an example to investigate multiple aspects of mycobacterial RNA biology that are likely to apply to other M. tuberculosis sRNAs and mRNAs. We have found that accumulation of this particular sRNA is slow but robust as cells enter stationary phase. Using reporter gene assays, we find that the sRNA core promoter is activated by DosR, and we have renamed the sRNA DrrS for DosR Regulated sRNA. Moreover, we show that DrrS is transcribed as a longer precursor, DrrS+, which is rapidly processed to the mature and highly stable DrrS. We characterise, for the first time in mycobacteria, an RNA structural determinant involved in this extraordinary stability and we show how the addition of a few nucleotides can lead to acute destabilisation. Finally, we show how this RNA element can enhance expression of a heterologous gene. Thus, the element, as well as its destabilising derivatives may be employed to post-transcriptionally regulate gene expression in mycobacteria in combination with different promoter variants. Moreover, our findings will facilitate further investigations into the severely understudied topic of mycobacterial RNA biology and into the role that regulatory RNA plays in M. tuberculosis pathogenesis.

  4. Rare earth elements in Angra dos Reis and Lewis Cliff 86010, two meteorites with similar but distinct magma evolutions

    NASA Technical Reports Server (NTRS)

    Crozaz, Ghislaine; Mckay, Gordon

    1990-01-01

    Data are presented on ion microprobe measurements of REE and selected trace element abundances in individual grains of merrillite, fassaite, olivine, kirschsteinite, and plagioclase of Lewis Cliff 86010 (LEW 86010) meteorite and in merrillite and fassaite grains of Angra dos Reis (ADOR). Results show a close relationship between the two meteorites and support a magmatic origin for LEW 86010. However, the measurements indicate that, despite numerous common characteristics, the two meteorites must have been produced in separate magmatic events involving similar but distinct processes and parent melts.

  5. The influence of climate change on wine production - the case of the Touriga Nacional grape variety (Quinta dos Termos, Portugal)

    NASA Astrophysics Data System (ADS)

    Fonseca, João

    2017-04-01

    The regional and local climate, heavily influenced by global climate change, has strong implications for agriculture. Wine production which has specific characteristics in terms of climate and soil is undoubtedly one of the economic activities strongly influenced by climate change. Quinta dos Termos located in Beira Interior (Belmonte, Portugal) is the largest wine producer in the DOC Beira Interior region, producing premium to hiper premium wines of excellence, marketed at both national and international levels, and cultivates the vineyards according to the rules of Integrated Crop Management. Moreover, grapes are free from herbicides, pesticides or any other chemicals that can be harmful to the environment and health. These factors have contributed to the socio-economic development of the region, creating wealth, favoring employment and promoting tourism. The quality of the wines produced by Quinta dos Termos result from its terroir, given its granite region, the sun exposure, the wind protection, the atmospheric humidity and temperature, the soil water content, the mineralogical/organic composition and soil porosity. These factors favor unique conditions for the cultivation of Touriga Nacional grape variety, which is recognized by its extremely complex color and aroma, which allows the production of wines with great balance and a good ageing potential. Touriga Nacional, a red grape variety of Portuguese origin with high qualitative excellence and reputation and much appreciated worldwide, is versatile to several types of soils and resistant to high thermal amplitudes. Nevertheless, the climatic changes that has been gradually verified, the type of crop management, and in particular the reputation of Touriga Nacional grape variety, may be compromised in the long term, given that these characteristics are strongly influenced by the climate and soil. Aware of that, Quinta dos Termos has been performing a monitoring of the vineyards in terms of pedological treatment

  6. Perfil de temperatura dos funis magnetosféricos de estrelas T Tauri com aquecimento alfvênico

    NASA Astrophysics Data System (ADS)

    Vasconcelos, M. J.

    2003-08-01

    Estrelas T Tauri Clássicas são objetos jovens circundados por discos de gás e poeira e que apresentam uma intensa atividade magnética. Seu espectro mostra linhas de emissão alargadas que são razoavelmente reproduzidas nos modelos de acresção magnetosférica. No entanto, o perfil de temperatura dos funis magnéticos é desconhecido. Aquecimento magnético compressional e difusão ambipolar foram considerados para estas estruturas, porém as temperaturas obtidas não são suficientes para explicar as observações. Neste trabalho, examinamos o aquecimento gerado pelo amortecimento de ondas Alfvén através de quatro mecanismos, os amortecimentos não-linear, turbulento, viscoso-resistivo e colisional como função da freqüência da onda. Inicialmente, a temperatura é ajustada para reproduzir as observações e o grau de turbulência requerido para que o mecanismo seja viável é calculado. Os resultados mostram que este é compatível com os dados observacionais. Apresentam-se, também, resultados preliminares do cálculo auto-consistente do perfil de temperatura dos funis, levando-se em conta fontes de aquecimento Alfvênica e fontes de resfriamento.

  7. Species richness of fern and lycophyte in an urban park in the Rio dos Sinos basin, Southern Brazil.

    PubMed

    Schmitt, J L; Goetz, M N B

    2010-12-01

    In the northeastern region of the State of Rio Grande do Sul in Southern Brazil, specifically in the Rio dos Sinos basin, urban parks are an important alternative for the conservation of the remaining natural habitats, as well as for the maintenance and perpetuation of biodiversity. A floristic survey of fern and lycophyte species in the Parque Municipal Henrique Luís Roessler (PMHLR) (29º 41' S and 51º 06' W; alt. 16.4 m) in Novo Hamburgo, (State of Rio Grande do Sul, RS) described their life-forms, as well as substrates and preferential environments. Forty-three species, 30 genera and 15 families were found, 39 of which were ferns. The hemicryptophytes had the highest species richness (26), 17 of which were repent, and nine, rosulate. Most species were found in terrestrial substrates (32) and inside the forest (29). Species richness in the PMHLR corresponded to about 13% of the total fern and lycophyte species listed for the State of Rio Grande do Sul, which demonstrates the importance of conservation areas in the Rio dos Sinos basin as an alternative to the preservation of local biodiversity.

  8. Didelphidae marsupials (Mammalia, Didelphimorphia) from the late Pleistocene deposit of the Gruta dos Moura Cave, northern Brazil.

    PubMed

    Nova, Patricia Villa; Avilla, Leonardo S; Oliveira, Édison V

    2015-03-01

    The present study acknowledges the diversity of fossil marsupials from the Gruta dos Moura cave, as well as environmental and climatic aspects during the Quaternary. The results show that this is the largest diversity of Pleistocene marsupials recorded in a single cave: Didelphis albiventris, D. aurita, Gracilinanus agilis, G. microtarsus, Marmosa murina, Monodelphis brevicaudata, M. domestica and Sairadelphys tocantinensis. Furthermore, the described specimens are also part of the only fossil assemblage unequivocally referable to the late Pleistocene. Paleontological studies suggest an intimate association with dry and open environments with high abundance of water sources. Since most of the identified taxa are characteristic of open forests and gallery forests, this could represent the actual environment around the Gruta dos Moura cave. Recent studies identified sympatric occurrences between species from open and dry environments and species from humid forests that were identified among our material and are characteristic of humid regions. Therefore, these species could inhabit gallery forests and capons, or even ecotones, inside a dry and open environment. Moreover, the extinction of Sairadelphys could also indicate that the climatic and environmental conditions changed or that the past environment was more heterogeneous than the current environment of the region.

  9. Cmr is a redox-responsive regulator of DosR that contributes to M. tuberculosis virulence

    PubMed Central

    Bochkareva, Aleksandra; Rolfe, Matthew D.; Hunt, Debbie M.; Kahramanoglou, Christina; Braun, Yvonne; Rodgers, Angela; Blockley, Alix; Coade, Stephen; Lougheed, Kathryn E.A.; Hafneh, Nor Azian; Glenn, Sarah M.; Crack, Jason C.; Le Brun, Nick E.; Saldanha, José W.; Makarov, Vadim; Nobeli, Irene; Mukamolova, Galina V.; Buxton, Roger S.; Green, Jeffrey

    2017-01-01

    Abstract Mycobacterium tuberculosis (MTb) is the causative agent of pulmonary tuberculosis (TB). MTb colonizes the human lung, often entering a non-replicating state before progressing to life-threatening active infections. Transcriptional reprogramming is essential for TB pathogenesis. In vitro, Cmr (a member of the CRP/FNR super-family of transcription regulators) bound at a single DNA site to act as a dual regulator of cmr transcription and an activator of the divergent rv1676 gene. Transcriptional profiling and DNA-binding assays suggested that Cmr directly represses dosR expression. The DosR regulon is thought to be involved in establishing latent tuberculosis infections in response to hypoxia and nitric oxide. Accordingly, DNA-binding by Cmr was severely impaired by nitrosation. A cmr mutant was better able to survive a nitrosative stress challenge but was attenuated in a mouse aerosol infection model. The complemented mutant exhibited a ∼2-fold increase in cmr expression, which led to increased sensitivity to nitrosative stress. This, and the inability to restore wild-type behaviour in the infection model, suggests that precise regulation of the cmr locus, which is associated with Region of Difference 150 in hypervirulent Beijing strains of Mtb, is important for TB pathogenesis. PMID:28482027

  10. Supporting Security against SYN Flooding Attack in Distributed DoS Via Measuring IPFIX-Based Traffic

    NASA Astrophysics Data System (ADS)

    Alipour, H.; Kia, M. Kashefi; Esmaeili, M.

    Distributed denial-of-service attacks on public servers after 2000 have become a serious problem. In the distributed denial-of-service (DDoS) attacks often seen recently, multiple distributed nodes concurrently attack a single server. To assure that network services will not be interrupted, faster and more effective defense mechanisms is needed to protect against malicious traffic, especially SYN floods. One problem in detecting SYN flood traffic is that server nodes or firewalls cannot distinguish the SYN packets of normal TCP connections from those of a SYN flood attack. Our method, FDFIX, relies on the use of monitoring and measurement techniques to evaluate the impact of DoS attacks. It uses flow based measurements. Capturing flow information is very important for detecting DoS and also other kinds of attacks. Flow monitoring allows detecting suspicious traffics and in the next step can analyze attacking flows and the results can be used for defense methods. Our method provides required information for many mechanisms that use traffic measurement as their input.

  11. Degradability of dimethyl terephthalate by Variovorax paradoxus T4 and Sphingomonas yanoikuyae DOS01 isolated from deep-ocean sediments.

    PubMed

    Wang, Yu Ping; Gu, Ji-Dong

    2006-08-01

    Two strains of bacteria were isolated from deep-ocean sediments of the South China Sea using enrichment culturing technique and they were identified as Sphingomonas yanoikuyae DOS01 (AY878409) and Variovorax paradoxus T4 (AY878410) based on 16S rRNA gene sequences. S. yanoikuyae DOS01 was only capable of transforming dimethyl terephthalate (DMTP) to monomethyl terephthalate (MMTP) without further degradation while V. paradoxus T4 exhibited ability in mineralizing DMTP as the sole source of carbon and energy. The biochemical pathway of DMTP degradation was through MMTP and terephthalic acid (TA) as major detectable degradation intermediates in the culture media by both microorganisms. V. paradoxus T4 utilized DMTP and MMTP via hydrolysis of diester and monoester in the initial steps in degradation as confirmed by total organic carbon analysis of the culture medium and esterase activity assay of the lysed cells and fraction. The specific hydrolysis activity of esterase induced by DMTP or MMTP showed that greater hydrolysis of p-nitrophenyl acetate by esterase induced by DMTP-grown cells than that induced by MMTP. Results of this research suggest that the cleavage of the two identical carboxylic ester groups of phthalate diester are carried out by highly specific esterases of the same bacteria in the environment.

  12. Evaluating microvascular obstruction after acute myocardial infarction using cardiac magnetic resonance imaging and 201-thallium and 99m-technetium pyrophosphate scintigraphy.

    PubMed

    Onishi, Takayuki; Kobayashi, Isshi; Onishi, Yuko; Kawashima, Tomoyuki; Muramoto, Hirotaka; Nakamura, Hiroaki; Nagata, Yasutoshi; Umezawa, Shigeo; Niwa, Akihiro

    2010-11-01

    Few studies have compared the ability of cardiac magnetic resonance (CMR) with that of scintigraphy using 201-thallium (201-Tl) and 99m-technetium pyrophosphate (99m-Tc PYP) to evaluate microvascular obstructions (MOs). In the present study the relationship between the scintigraphic and CMR characteristics of MOs after acute myocardial infarction (MI) was examined. The 14 patients (age 69±8 years, 11 males) underwent 201-Tl/99m-Tc PYP SPECT 7±3 days, initial CMR 16±12 days, and follow-up CMR 193±20 days after a reperfused first acute MI. Each image was analyzed using a 17-segment model. Segmental extent of delayed enhancement (DE), wall motion (WM) and degree of 201-Tl uptake were scored in 238 segments. Of 91 MI segments, MO was recognized in 22 (25%) segments on CMR. WM was significantly better in proportion to 201-Tl uptake (P=0.01) in MO segments. All 8 MO segments with WM improvement at follow-up had 99m-Tc PYP uptake, although only 3 (21%) of 14 MO segments that did not show WM improvement at follow-up had 99m-Tc PYP uptake (P=0.001). 99m-Tc PYP and 201-Tl scintigraphy have the potential to predict WM status and improvement of the MO region after reperfused acute MI.

  13. Effect of eating on thallium myocardial imaging

    SciTech Connect

    Wilson, R.A.; Sullivan, P.J.; Okada, R.D.; Boucher, C.A.; Morris, C.; Pohost, G.M.; Strauss, H.W.

    1986-02-01

    To determine if eating between initial and delayed thallium images alters the appearance of the delayed thallium scan, a prospective study was performed; 184 subjects sent for routine thallium imaging were randomized into two groups, those who ate a meal high in carbohydrates between initial and delayed thallium myocardial images (n = 106), and those who fasted (n = 78). The /sup 201/Tl images were interpreted in blinded fashion for global myocardial and pulmonary clearance of /sup 201/Tl myocardial defects. The eating group had a significantly lower incidence of transient myocardial defects compared to the noneating group (7 percent vs 18 percent, respectively; p less than 0.05). The time between initial and delayed images and the incidence of exercise-induced ischemic ST-segment depression or pathologic Q waves on the electrocardiogram were not significantly different between the two groups. These data suggest that eating a high-carbohydrate meal between initial and delayed /sup 201/Tl images causes increased /sup 201/Tl myocardial clearance rates and may alter /sup 201/Tl myocardial redistribution over time.

  14. Dual tracer autoradiographic study with thallium-201 and radioiodinated fatty acid in cardiomyopathic hamsters

    SciTech Connect

    Kurata, C.; Kobayashi, A.; Yamazaki, N.

    1989-01-01

    To investigate the usefulness of myocardial scintigraphy with radioiodinated 15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) in cardiomyopathy, quantitative dual tracer autoradiographic study with /sup 201/Tl and (/sup 125/I)BMIPP was performed in 27 cardiomyopathic Bio 14.6 Syrian hamsters and eight normal hamsters. Furthermore, 16 Bio 14.6 Syrian hamsters aged 21 days were divided into verapamil-treated (during 70 days) and control groups (respectively, n = 8), and autoradiography with /sup 201/Tl and (/sup 125/I)BMIPP was performed. Quantitative autoradiography demonstrated an uncoupling of /sup 201/Tl and (/sup 125/I)BMIPP distributions and a regional heterogeneity of (/sup 125/I)BMIPP distribution in cardiomyopathic hamsters aged more than 2 mo, while normal hamsters showed only mild heterogeneity of (/sup 125/I)BMIPP distribution without an uncoupling of tracers. Age-matched comparison between normal and cardiomyopathic hamsters (5-8 mo old) demonstrated that a difference between their (/sup 125/I)BMIPP distributions are more marked than that between their /sup 201/Tl distributions. Furthermore, (/sup 125/I)BMIPP visualized effects of verapamil on cardiomyopathy more distinctly than did /sup 201/Tl. In conclusion, myocardial imaging with (/sup 123/I)BMIPP could be useful for investigating cardiomyopathy and evaluating the efficacy of therapeutic intervention in patients with cardiomyopathy.

  15. Detection of cardiomyopathy in an animal model using quantitative autoradiography

    SciTech Connect

    Kubota, K.; Som, P.; Oster, Z.H.; Brill, A.B.; Goodman, M.M.; Knapp, F.F. Jr.; Atkins, H.L.; Sole, M.J.

    1988-10-01

    A fatty acid analog (15-p-iodophenyl)-3,3 dimethyl-pentadecanoic acid (DMIPP) was studied in cardiomyopathic (CM) and normal age-matched Syrian hamsters. Dual tracer quantitative wholebody autoradiography (QARG) with DMIPP and 2-(/sup 14/C(U))-2-deoxy-2-fluoro-D-glucose (FDG) or with FDG and /sup 201/Tl enabled comparison of the uptake of a fatty acid and a glucose analog with the blood flow. These comparisons were carried out at the onset and mid-stage of the disease before congestive failure developed. Groups of CM and normal animals were treated with verapamil from the age of 26 days, before the onset of the disease for 41 days. In CM hearts, areas of decreased DMIPP uptake were seen. These areas were much larger than the decrease in uptake of FDG or /sup 201/Tl. In early CM only minimal changes in FDG or /sup 201/Tl uptake were observed as compared to controls. Treatment of CM-prone animals with verapamil prevented any changes in DMIPP, FDG, or /sup 201/Tl uptake. DMIPP seems to be a more sensitive indicator of early cardiomyopathic changes as compared to /sup 201/Tl or FDG. The trial of DMIPP and SPECT in the diagnosis of human disease, as well as for monitoring the effects of drugs which may prevent it seems to be warranted.

  16. Contextual variation in young children's observed disruptive behavior on the DB-DOS: implications for early identification.

    PubMed

    Petitclerc, Amélie; Briggs-Gowan, Margaret J; Estabrook, Ryne; Burns, James L; Anderson, Erica L; McCarthy, Kimberly J; Wakschlag, Lauren S

    2015-09-01

    Contextual variation in child disruptive behavior is well documented but remains poorly understood. We first examine how variation in observed disruptive behavior across interactional contexts is associated with maternal reports of contextual variation in oppositional-defiant behavior and functional impairment. Second, we test whether child inhibitory control explains the magnitude of contextual variation in observed disruptive behavior. Participants are 497 young children (mean age = 4 years, 11 months) from a subsample of the MAPS, a sociodemographically diverse pediatric sample, enriched for risk of disruptive behavior. Observed anger modulation and behavioral regulation problems were coded on the Disruptive Behavior Diagnostic Observation Schedule (DB-DOS) during interactions with parent and examiner. Oppositional-defiant behavior, and impairment in relationships, with parents and nonparental adults, were measured with the Preschool Age Psychiatric Assessment (PAPA) interview with the mother. Functional impairment in the home and out-and-about was assessed with the Family Life Impairment Scale (FLIS), and expulsion from child care/school was measured with the baseline survey and FLIS. Observed disruptive behavior on the DB-DOS Parent Context was associated with oppositional-defiant behavior with parents, and with impairment at home and out-and-about. Observed disruptive behavior with the Examiner was associated with oppositional-defiant behavior with both parents and nonparental adults, impairment in relationships with nonparental adults, and child care/school expulsion. Differences in observed disruptive behavior in the Parent versus Examiner Contexts was related to the differences in maternal reports of oppositional-defiant behavior with parents versus nonparental adults. Children with larger decreases in disruptive behavior from Parent to Examiner Context had better inhibitory control and fewer attention-deficit/hyperactivity disorder symptoms. The DB-DOS

  17. Contextual variation in young children’s observed disruptive behavior on the DB-DOS: implications for early identification

    PubMed Central

    Petitclerc, Amélie; Briggs-Gowan, Margaret J.; Estabrook, Ryne; Burns, James L.; Anderson, Erica L.; McCarthy, Kimberly J.; Wakschlag, Lauren S.

    2015-01-01

    Background Contextual variation in child disruptive behavior is well documented but remains poorly understood. We first examine how variation in observed disruptive behavior across interactional contexts is associated with maternal reports of contextual variation in oppositional-defiant behavior and functional impairment. Second, we test whether child inhibitory control explains the magnitude of contextual variation in observed disruptive behavior. Methods Participants are 497 young children (mean age = 4 years, 11 months) from a subsample of the MAPS, a sociodemographically diverse pediatric sample, enriched for risk of disruptive behavior. Observed anger modulation and behavioral regulation problems were coded on the Disruptive Behavior Diagnostic Observation Schedule (DB-DOS) during interactions with parent and examiner. Oppositional-defiant behavior, and impairment in relationships, with parents and nonparental adults, were measured with the Preschool Age Psychiatric Assessment (PAPA) interview with the mother. Functional impairment in the home and out-and-about was assessed with the Family Life Impairment Scale (FLIS), and expulsion from child care/school was measured with the baseline survey and FLIS. Results Observed disruptive behavior on the DB-DOS Parent Context was associated with oppositional-defiant behavior with parents, and with impairment at home and out-and-about. Observed disruptive behavior with the Examiner was associated with oppositional-defiant behavior with both parents and nonparental adults, impairment in relationships with nonparental adults, and child care/school expulsion. Differences in observed disruptive behavior in the Parent versus Examiner Contexts was related to the differences in maternal reports of oppositional-defiant behavior with parents versus nonparental adults. Children with larger decreases in disruptive behavior from Parent to Examiner Context had better inhibitory control and fewer attention

  18. [The Arabic influence in the "Colóquios dos simples e drogas da India" of Garcia da Orta].

    PubMed

    Ricordel, Joëlle

    2015-09-01

    The "Colóquios dos simples e drogas he cousas medicinais de Índia" (Conversations on the simples, drugs and medicinal substances of India) (1563) of Garcia da Orta is a botanical and pharmacognosy book. The author is a Portuguese physician who studied in the Spanish universities and practiced medicine mainly in India. He studies in short chapters presented in the form of dialogues about sixty simples. Sources to which he refers are indicative of a "classical" training, but also the mark of a curious and open mind to different cultures. The Arabic sources are numerous and mainly concern the identification of substances by abundant synonyms of their names in foreign languages and different medicinal uses that may have been done by the ancient physicians. However, Da Orta is critical with respect to these sources, seeking contradictions and differences of opinion among authors. He confronts them with the oral information collected thanks to a wide network of contacts.

  19. NGC 2287: Un cúmulo abierto rico en binarias espectroscópicas de dos espectros

    NASA Astrophysics Data System (ADS)

    Levato, H.; Malaroda, S.; García, B.; Grosso, M.

    NGC 2287 contiene 100 estrellas con buena fotometría y 40 con tipos MK. En 1979 Levato et al., usando la técnica de la clasificación espectral, descubrieron que la mayoría de las estrellas en el rango B8-A0 eran binarias espectroscópicas con una inusual proporción de binarias con dos espectros. El presente proyecto tuvo el propósito de confirmar la naturaleza binaria de los miembros del cúmulo. Hemos obtenido espectros con resolución 14000 de 15 estrellas clasificadas como binarias. Los espectros, que abarcan la región λ 3500-λ 6000 Å, permitieron confirmar la naturaleza binaria de varias de las estrellas en la muestra. Hacemos notar el considerable interés astrofísico de este cúmulo abierto.

  20. Another new and threatened species of lancehead genus Bothrops (Serpentes, Viperidae) from Ilha dos Franceses, Southeastern Brazil.

    PubMed

    Barbo, Fausto E; Gasparini, João Luiz; Almeida, Antonio P; Zaher, Hussam; Grazziotin, Felipe G; Gusmão, Rodrigo B; Ferrarini, José Mário G; Sawaya, Ricardo J

    2016-04-04

    A new insular species of the genus Bothrops is described from Ilha dos Franceses, a small island off the coast of Espírito Santo State, in southeastern Brazil. The new species differs from mainland populations of B. jararaca mainly by its small size, relative longer tail, relative smaller head length, and relative larger eyes. The new species is distinguished from B. alcatraz, B. insularis and B. otavioi by the higher number of ventral and subcaudal scales, relative longer tail and smaller head. The new species is highly abundant on the island, being nocturnal, semiarboreal, and feeding on small lizards and centipeds. Due its unique and restricted area of occurrence, declining quality of habitat, and constant use of the island for tourism, the new species may be considered as critically endangered.

  1. Application of geostatistical methods to arsenic data from soil samples of the Cova dos Mouros mine (Vila Verde-Portugal).

    PubMed

    Reis, A P; Sousa, A J; Da Silva, E Ferreira; Fonseca, E Cardoso

    2005-09-01

    A total of 286 soil samples were collected in the Cova dos Mouros area. All samples were dry sieved into the <200 mesh size fraction and analysed for Fe, Cu, Zn, Pb, Co, Ni, Bi and Mn by atomic absorption spectrometry (AAS) and for As, Se, Sb and Te by atomic absorption spectrometry-hydrid generation (AAS-HG). Only the results of arsenic are discussed in this paper although the survey was extended to all analysed chemical elements. The purpose of this study was to make a risk probability mapping for arsenic that would allow better knowledge about the vulnerability of the soil to arsenic contamination. To achieve this purpose, the initial variable was transformed into an indicator variable using as thresholds the risk-based standards (intervention values) for soils, as proposed by [Swartjes 1999. Risk based assessment of soil and groundwater quality in the Netherlands: Standards and remediation. J. Geochem. Explor.73 1-10]. To account for spatial structure, sample variograms were computed for the main directions of the sampling grid and a spherical model was fitted to each sample variogram (arsenic variable and indicator variables). The parameters of the spherical model fitted to the arsenic variable were used to predict arsenic concentrations at unsampled locations. A risk probability mapping was also done to assess the vulnerability of the soil towards the mining works. The parameters of the spherical model fitted to each indicator variable were used to estimate probabilities of exceeding the corresponding threshold. The use of indicator kriging as an alternative to ordinary kriging for the soil data of Cova dos Mouros produced unbiased probability maps that allowed assessment of the quality of the soil.

  2. Observações no âmbito dos "additional programs" do satélite COROT

    NASA Astrophysics Data System (ADS)

    Janot Pacheco, E.

    2003-08-01

    O satélite Fraco-europeu COROT fará fotometria de altissima precisão (pretende-se atingir uma parte em um milhão), grande campo (3x3 graus) e por longos períodos, de duas regiões pré-determinadas do céu, com 10 graus de raio. Suas finalidades básicas serão estudos em sismologia estelar e a procura de exoplanetas. A comunidade astronômica brasileira participará dessa missão espacial, com direitos iguais aos dos parceiros europeus. Isso se deve a que o satélite utilizará a estação de recepção de dados de Natal (INPE), 5 a 6 brasileiros participarão das equipes de software e cientistas do país atuarão na fase de pré-lançamento. Apresentamos nesta comunicação sugestões para a preparação de propostas de observações com COROT, no âmbito dos Programas Adicionais, que contemplam outros projetos que não de sismologia ou exoplanetas. As últimas definições técnicas e decisões tomadas na 4th Corot Week de junho último serão igualmente apresentadas, em particular quanto às regiões de observação escolhidas e quanto aos procedimentos a seguir para se propor observações.

  3. Long term exposure to organochlorine pesticides and thyroid function in children from Cidade dos Meninos, Rio de Janeiro, Brazil.

    PubMed

    Freire, Carmen; Koifman, Rosalina Jorge; Sarcinelli, Paula; Rosa, Ana Cristina; Clapauch, Ruth; Koifman, Sergio

    2012-08-01

    A pesticide factory in Cidade dos Meninos village, Duque de Caxias County, Rio de Janeiro, Brazil, ended its activity in 1961, leading to widespread contamination of the environment by several organochlorine pesticides. The aim of this study was to investigate the effects of chronic exposure to organochlorine pesticides on thyroid hormone levels in children residing in Cidade dos Meninos. In a population-based survey carried out between 2003 and 2004, serum concentration of 19 pesticides and levels of free thyroxine (T4), total triiodothyronine (T3) and thyroid-stimulating hormone (TSH) were determined in 193 children younger than 15 years old. Multivariate linear regression was conducted to examine thyroid hormone levels according to quintiles of organochlorine exposure, controlling for age, gender and serum lipid content. Free T4 and TSH levels were within reference values (0.7-1.8 ng/dl and 0.35-5.5 mU/l), whereas total T3 was above the reference range (80-180 ng/dl) in 28% of children. More than 60% of the children had detectable levels of most organochlorine pesticides. With the exception of heptachlor and methoxychlor, total T3 levels showed a significant increasing linear trend regardless of pesticide type to which children were exposed. Free T4 levels were positively and significantly associated only with exposure to p,p'-DDD, endosulfan 1, and dieldrin. No significant trend was found for TSH. Data showed that exposure of children to organochlorine pesticides produced a significant increase in serum total T3 concentrations. The clinical implications of such a total T3 elevation and subsequent development are uncertain and warrant the need for health monitoring of these children.

  4. Thallium-201 SPECT imaging of brain tumors: Methods and results

    SciTech Connect

    Kim, K.T.; Black, K.L.; Marciano, D.; Mazziotta, J.C.; Guze, B.H.; Grafton, S.; Hawkins, R.A.; Becker, D.P. )

    1990-06-01

    Recent studies suggest that thallium-201 ({sup 201}Tl) planar scans of brain tumors more accurately reflect viable tumor burden than CT, MRI, or radionuclide studies with other single-photon emitting compounds. We have previously reported the utility of {sup 201}Tl SPECT index in distinguishing low- from high-grade gliomas elsewhere. Here we describe the technical considerations of deriving a simple {sup 201}Tl index, based on uptake in the tumor normalized to homologous contralateral tissue, from SPECT images of brain tumors. We evaluated the importance of consistently correcting for tissue attenuation, as it may achieve better lesion discrimination on qualitative inspection, and the methodologic limitations imposed by partial volume effects at the limits of resolution.

  5. Reproducibility of quantitative planar thallium-201 scintigraphy: quantitative criteria for reversibility of myocardial perfusion defects

    SciTech Connect

    Sigal, S.L.; Soufer, R.; Fetterman, R.C.; Mattera, J.A.; Wackers, F.J. )

    1991-05-01

    Fifty-two paired stress/delayed planar {sup 201}TI studies (27 exercise studies, 25 dipyridamole studies) were processed twice by seven technologists to assess inter- and intraobserver variability. The reproducibility was inversely related to the size of {sup 201}Tl perfusion abnormalities. Intraobserver variability was not different between exercise and dipyridamole studies for lesions of similar size. Based upon intraobserver variability, objective quantitative criteria for reversibility of perfusion abnormalities were defined. These objective criteria were tested prospectively in a separate group of 35 {sup 201}Tl studies and compared with the subjective interpretation of quantitative circumferential profiles. Overall, exact agreement existed in 78% of images (kappa statistic k = 0.66). We conclude that quantification of planar {sup 201}Tl scans is highly reproducible, with acceptable inter- and intraobserver variability. Objective criteria for lesion reversibility correlated well with analysis by experienced observers.

  6. A prospective comparison of rubidium-82 PET and thallium-201 SPECT myocardial perfusion imaging utilizing a single dipyridamole stress in the diagnosis of coronary artery disease

    SciTech Connect

    Go, R.T.; Marwick, T.H.; MacIntyre, W.J.; Saha, G.B.; Neumann, D.R.; Underwood, D.A.; Simpfendorfer, C.C. )

    1990-12-01

    The purpose of the present study is to prospectively compare myocardial perfusion imaging with rubidium-82 ({sup 82}Rb) by positron emission tomography (PET) with thallium-201 ({sup 201}Tl) imaging by single-photon emission tomography (SPECT) by recording both studies with a single dipyridamole handgrip stress, and reading both sets of images with the same display technique. In a series of 202 patients with previous coronary arteriography, the sensitivity, specificity, and accuracy of {sup 82}Rb PET were 93%, 78%, and 90% and for {sup 201}Tl SPECT 76%, 80%, and 77%, respectively. When 70 patients with previous therapeutic interventions were excluded, the remaining 132 patients showed a sensitivity, specificity, and accuracy of 95%, 82% and 92% for {sup 82}Rb PET and 79%, 76%, and 78% for {sup 201}Tl SPECT. The improved contrast resolution of PET resulted in markedly superior images and a more confident identification of defects.

  7. Dynamics of the T cell response to Mycobacterium tuberculosis DosR and Rpf antigens in a Colombian population of household contacts of recently diagnosed pulmonary tuberculosis patients.

    PubMed

    Arroyo, Leonar; Rojas, Mauricio; Ortíz, Blanca L; Franken, Kees L M C; García, Luis F; Ottenhoff, Tom H M; Barrera, Luis F

    2016-03-01

    Immune response to DosR and Rpf antigens from Mycobacterium tuberculosis (Mtb) seems to be important for latency maintenance. Little is known about the dynamics of the immune response to these antigens in an endemic community. Thus, the IFNγ response and cytokine production in response to PPD, Esat6-Cfp10 (E6-C10), DosR and Rpf antigens in healthy HHC of tuberculosis (TB) patients over a 12 (T12) months period (short-term, stLTBI) was investigated. This response was compared with a group of LTBI, who have remained healthy for 5-7 years (long-term, ltLTBI). According to the IFNγ response, two groups of HHCs were identified in stLTBI in response to E6-C10. At T12, E6-C10(+) HHCs displayed a decrease in the IFNγ levels and a generalized decrease in cytokines production. The E6-C10(-) HHC showed an increase in the IFNγ response and cytokine levels. In stLTBI, the responses to E6-C10, DosR, and Rpf may be interpreted as a protective immune response controlling Mtb infection and may be leading to a state of latent infection. Comparing the response of stLTBI and ltLTBI, we observed significant changes in the proportions of CD45RO(+)CD27(+) T cells to specific DosR and Rpf, which may indicate a persistent immune response to Mtb antigens in ltLTBI.

  8. Mycobacterium tuberculosis DosR is Required for Activity of the PmbtB and PmbtI Promoters under Hypoxia

    PubMed Central

    Schreuder, Lise J.; Parish, Tanya

    2014-01-01

    Mycobacterium tuberculosis has the ability to survive for extended periods of time under conditions of low oxygen, low pH, low iron and low nutrients. The mycobactins (M. tuberculosis siderophores) play a key role in scavenging iron from the environment and are induced in response to low iron in an IdeR-regulated manner. We demonstrate that the promoters of two mycobactin gene (mbt) operons are also expressed during adaptation to low oxygen, and that this expression is dependent on the DosR regulator. Up-regulation of mbt operons induced by low iron was not DosR-dependent. DosR is a member of a two component regulatory system which responds to oxygen availability. Deletion of the DosR regulator led to increased expression of bacterioferritin and increased capacity to grow under iron depletion. These data provide a link between the mycobacterial response to two conditions likely to be encountered in vivo, low iron and low oxygen. PMID:25211224

  9. 48 CFR 653.219-71 - DOS form DS-4053, Department of State Mentor-Protégé Program Application.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., Department of State Mentor-Protégé Program Application. 653.219-71 Section 653.219-71 Federal Acquisition Regulations System DEPARTMENT OF STATE CLAUSES AND FORMS FORMS Prescription of Forms 653.219-71 DOS form DS-4053, Department of State Mentor-Protégé Program Application. As prescribed in 619.102-70(i),...

  10. 48 CFR 653.219-71 - DOS form DS-4053, Department of State Mentor-Protégé Program Application.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., Department of State Mentor-Protégé Program Application. 653.219-71 Section 653.219-71 Federal Acquisition Regulations System DEPARTMENT OF STATE CLAUSES AND FORMS FORMS Prescription of Forms 653.219-71 DOS form DS-4053, Department of State Mentor-Protégé Program Application. As prescribed in 619.102-70(i),...

  11. 48 CFR 653.219-71 - DOS form DS-4053, Department of State Mentor-Protégé Program Application.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., Department of State Mentor-Protégé Program Application. 653.219-71 Section 653.219-71 Federal Acquisition Regulations System DEPARTMENT OF STATE CLAUSES AND FORMS FORMS Prescription of Forms 653.219-71 DOS form DS-4053, Department of State Mentor-Protégé Program Application. As prescribed in 619.102-70(i),...

  12. 48 CFR 653.219-71 - DOS form DS-4053, Department of State Mentor-Protégé Program Application.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., Department of State Mentor-Protégé Program Application. 653.219-71 Section 653.219-71 Federal Acquisition Regulations System DEPARTMENT OF STATE CLAUSES AND FORMS FORMS Prescription of Forms 653.219-71 DOS form DS-4053, Department of State Mentor-Protégé Program Application. As prescribed in 619.102-70(i),...

  13. 48 CFR 653.219-71 - DOS form DS-4053, Department of State Mentor-Protégé Program Application.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., Department of State Mentor-Protégé Program Application. 653.219-71 Section 653.219-71 Federal Acquisition Regulations System DEPARTMENT OF STATE CLAUSES AND FORMS FORMS Prescription of Forms 653.219-71 DOS form DS-4053, Department of State Mentor-Protégé Program Application. As prescribed in 619.102-70(i),...

  14. Immunogenicity of Novel DosR Regulon-Encoded Candidate Antigens of Mycobacterium tuberculosis in Three High-Burden Populations in Africa▿ †

    PubMed Central

    Black, Gillian F.; Thiel, Bonnie A.; Ota, Martin O.; Parida, Shreemanta K.; Adegbola, Richard; Boom, W. Henry; Dockrell, Hazel M.; Franken, Kees L. M. C.; Friggen, Annemiek H.; Hill, Philip C.; Klein, Michel R.; Lalor, Maeve K.; Mayanja, Harriet; Schoolnik, Gary; Stanley, Kim; Weldingh, Karin; Kaufmann, Stefan H. E.; Walzl, Gerhard; Ottenhoff, Tom H. M.

    2009-01-01

    Increasing knowledge about DosR regulon-encoded proteins has led us to produce novel Mycobacterium tuberculosis antigens for immunogenicity testing in human populations in three countries in Africa to which tuberculosis (TB) is endemic. A total of 131 tuberculin skin test-positive and/or ESAT-6/CFP10-positive, human immunodeficiency virus-negative adult household contacts of active pulmonary TB cases from South Africa (n = 56), The Gambia (n = 26), and Uganda (n = 49) were tested for gamma interferon responses to 7 classical and 51 DosR regulon-encoded M. tuberculosis recombinant protein antigens. ESAT-6/CFP10 fusion protein evoked responses in >75% of study participants in all three countries. Of the DosR regulon-encoded antigens tested, Rv1733c was the most commonly recognized by participants from both South Africa and Uganda and the third most commonly recognized antigen in The Gambia. The four most frequently recognized DosR regulon-encoded antigens in Uganda (Rv1733c, Rv0081, Rv1735c, and Rv1737c) included the three most immunogenic antigens in South Africa. In contrast, Rv3131 induced the highest percentage of responders in Gambian contacts (38%), compared to only 3.4% of Ugandan contacts and no South African contacts. Appreciable percentages of TB contacts with a high likelihood of latent M. tuberculosis infection responded to several novel DosR regulon-encoded M. tuberculosis proteins. In addition to significant similarities in antigen recognition profiles between the three African population groups, there were also disparities, which may stem from genetic differences between both pathogen and host populations. Our findings have implications for the selection of potential TB vaccine candidates and for determining biosignatures of latent M. tuberculosis infection, active TB disease, and protective immunity. PMID:19553548

  15. MprA and DosR coregulate a Mycobacterium tuberculosis virulence operon encoding Rv1813c and Rv1812c.

    PubMed

    Bretl, Daniel J; He, Hongjun; Demetriadou, Crystalla; White, Mark J; Penoske, Renee M; Salzman, Nita H; Zahrt, Thomas C

    2012-09-01

    Mycobacterium tuberculosis remains a significant global pathogen, causing extensive morbidity and mortality worldwide. This bacterium persists within granulomatous lesions in a poorly characterized, nonreplicating state. The two-component signal transduction systems MprAB and DosRS-DosT (DevRS-Rv2027c) are responsive to conditions likely to be present within granulomatous lesions and mediate aspects of M. tuberculosis persistence in vitro and in vivo. Here, we describe a previously uncharacterized locus, Rv1813c-Rv1812c, that is coregulated by both MprA and DosR. We demonstrate that MprA and DosR bind to adjacent and overlapping sequences within the promoter region of Rv1813c and direct transcription from an initiation site located several hundred base pairs upstream of the Rv1813 translation start site. We further show that Rv1813c and Rv1812c are cotranscribed, and that the genomic organization of this operon is specific to M. tuberculosis and Mycobacterium bovis. Although Rv1813c is not required for survival of M. tuberculosis in vitro, including under conditions in which MprAB and DosRST signaling are activated, an M. tuberculosis ΔRv1813c mutant is attenuated in the low-dose aerosol model of murine tuberculosis, where it exhibits a lower bacterial burden, delayed time to death, and decreased ability to stimulate proinflammatory cytokines interleukin-1β (IL-1β) and IL-12. Interestingly, overcomplementation of these phenotypes is observed in the M. tuberculosis ΔRv1813c mutant expressing both Rv1813c and Rv1812c, but not Rv1813c alone, in trans. Therefore, Rv1813c and Rv1812c may represent general stress-responsive elements that are necessary for aspects of M. tuberculosis virulence and the host immune response to infection.

  16. MprA and DosR Coregulate a Mycobacterium tuberculosis Virulence Operon Encoding Rv1813c and Rv1812c

    PubMed Central

    Bretl, Daniel J.; He, Hongjun; Demetriadou, Crystalla; White, Mark J.; Penoske, Renee M.; Salzman, Nita H.

    2012-01-01

    Mycobacterium tuberculosis remains a significant global pathogen, causing extensive morbidity and mortality worldwide. This bacterium persists within granulomatous lesions in a poorly characterized, nonreplicating state. The two-component signal transduction systems MprAB and DosRS-DosT (DevRS-Rv2027c) are responsive to conditions likely to be present within granulomatous lesions and mediate aspects of M. tuberculosis persistence in vitro and in vivo. Here, we describe a previously uncharacterized locus, Rv1813c-Rv1812c, that is coregulated by both MprA and DosR. We demonstrate that MprA and DosR bind to adjacent and overlapping sequences within the promoter region of Rv1813c and direct transcription from an initiation site located several hundred base pairs upstream of the Rv1813 translation start site. We further show that Rv1813c and Rv1812c are cotranscribed, and that the genomic organization of this operon is specific to M. tuberculosis and Mycobacterium bovis. Although Rv1813c is not required for survival of M. tuberculosis in vitro, including under conditions in which MprAB and DosRST signaling are activated, an M. tuberculosis ΔRv1813c mutant is attenuated in the low-dose aerosol model of murine tuberculosis, where it exhibits a lower bacterial burden, delayed time to death, and decreased ability to stimulate proinflammatory cytokines interleukin-1β (IL-1β) and IL-12. Interestingly, overcomplementation of these phenotypes is observed in the M. tuberculosis ΔRv1813c mutant expressing both Rv1813c and Rv1812c, but not Rv1813c alone, in trans. Therefore, Rv1813c and Rv1812c may represent general stress-responsive elements that are necessary for aspects of M. tuberculosis virulence and the host immune response to infection. PMID:22689819

  17. Activation of ATP binding for the autophosphorylation of DosS, a Mycobacterium tuberculosis histidine kinase lacking an ATP lid motif.

    PubMed

    Cho, Ha Yeon; Lee, Young-Hoon; Bae, Young-Seuk; Kim, Eungbin; Kang, Beom Sik

    2013-05-03

    The sensor histidine kinases of Mycobacterium tuberculosis, DosS and DosT, are responsible for sensing hypoxic conditions and consist of sensor and kinase cores responsible for accepting signals and phosphorylation activity, respectively. The kinase core contains a dimerization and histidine phosphate-accepting (DHp) domain and an ATP binding domain (ABD). The 13 histidine kinase genes of M. tuberculosis can be grouped based on the presence or absence of the ATP lid motif and F box (elements known to play roles in ATP binding) in their ABDs; DosS and DosT have ABDs lacking both these elements, and the crystal structures of their ABDs indicated that they were unsuitable for ATP binding, as a short loop covers the putative ATP binding site. Although the ABD alone cannot bind ATP, the kinase core is functional in autophosphorylation. Appropriate spatial arrangement of the ABD and DHp domain within the kinase core is required for both autophosphorylation and ATP binding. An ionic interaction between Arg(440) in the DHp domain and Glu(537) in the short loop of the ABD is available and may open the ATP binding site, by repositioning the short loop away from the site. Mutations at Arg(440) and Glu(537) reduce autophosphorylation activity. Unlike other histidine kinases containing an ATP lid, which protects bound ATP, DosS is unable to accept ATP until the ABD is properly positioned relative to the histidine; this may prevent unexpected ATP reactions. ATP binding can, therefore, function as a control mechanism for histidine kinase activity.

  18. Utility of thallium-201 scintigraphy in Tolosa-Hunt syndrome.

    PubMed

    Kakisaka, Yosuke; Kobayashi, Tomoko; Uematsu, Mitsugu; Numata, Yurika; Hirose, Mieko; Hino-Fukuyo, Naomi; Tsuchiya, Shigeru; Doi, Hiroshi; Fukuda, Hiroshi; Kure, Shigeo

    2013-01-01

    Tolosa-Hunt syndrome (THS) is a rare disorder, especially in the pediatric population, characterized by unilateral painful ophthalmoplegia with a relapsing-remitting course. Because the diagnosis of THS is based on the exclusion of other causes of painful ophthalmoplegia, attention should be paid to possible alternative diagnoses. Thallium-201 chloride ((201)Tl) scintigraphy has been used to evaluate tissue histology in clinical oncology with a marker, the retention index (RI). A higher value indicates histological malignancy. Although its utility in pediatric THS has not been discussed, we suggest that (201)Tl scintigraphy may be informative as a marker in the diagnosis. We present an 11-year-old boy with THS who was evaluated with (201)Tl scintigraphy before treatment with corticosteroids, when he had headache, photophobia, and diplopia. The RI of (201)Tl indicated that the lesion would be benign. Although his clinical symptoms did not fulfill the THS criteria completely, his eye symptoms disappeared 2 weeks after corticosteroid treatment, which was not within the 72 h as in the diagnostic criteria of THS. He has been symptom-free for more than 2 years with only an initial 4-week corticosteroid therapy. This report not only shows the potential of (201)Tl scintigraphy to contribute to the correct diagnosis of pediatric THS but also suggests the possibility that the diagnosis of THS could be supported uniquely even in a pediatric THS-suspicious patient who did not fulfill the current THS criteria completely. In conclusion, we suggest that (201)Tl scintigraphy may be useful for making the diagnosis of THS, especially in pediatric patients.

  19. [Manifestatations of violence in adolescents in public schools in the municipality of Jaboatão dos Guararapes].

    PubMed

    Melo, Monica Cristina Batista de; Barros, Erika Neves de; Almeida, Andréa Maria Lages Gomes de

    2011-10-01

    Adolescence is a period in human development characterized by profound biological, psychological and social modifications affecting both adolescents and their entire social and family environment. This stage, which has good character forming opportunities, is also permeated by various risks, including violence. Nowadays, violence is the main cause of death among adolescents and is considered a public health concern. This research sought to investigate manifestations of violence in adolescents from public schools of the municipality of Jaboatão dos Guararapes. This is a qualitative study, in which the data obtained from a questionnaire was analyzed using the content analysis technique. The results show that the main manifestations of violence involve harm to others. Drug usage was revealed as the main motive behind physical violence. The deployment of more policemen was the strategy most cited and strengthening the family unit was the most commented preventative measure. In conclusion, the importance of further discussion about disguised manifestations of violence is clear as this would contribute to reflections on new prevention proposals and greater visibility of the phenomenon.

  20. Impacts of the globalized economy on the environment: the tanning industry in the Vale do Rio dos Sinos.

    PubMed

    Figueiredo-Sganderla, J A; Prodanov, C C; Daroit, D

    2010-12-01

    This case study analysed the impact of the global economy on the environment of the Vale do Rio do Sinos region in southern Brazil. Interviews and questionnaires were used to collect data from social, cultural, economic and political agents in this region, and documents about the tanning industry were reviewed and analysed. Global perspectives and local conditions were brought together to understand the causes and consequences of social, political and economic structures and to evaluate the intrinsic association of the tanning industry with the social, historical and cultural development of the Vale do Rio dos Sinos. The behaviour of the local community, where individuals believe that progress is primordially based on industrial development and go to any lengths to achieve it, was also studied. The analysis of industries that have a high contamination potential revealed that dirty industries moved from central to peripheral countries up to the 1980s, but movement is currently internal and occurs between states in Brazil due to several types of incentives.

  1. Groundwater radon, radium and uranium concentrations in Região dos Lagos, Rio de Janeiro State, Brazil.

    PubMed

    Almeida, R M R; Lauria, D C; Ferreira, A C; Sracek, O

    2004-01-01

    Ground water from Região dos Lagos, a coastal area of Rio de Janeiro state, was analysed for (226)Ra, (228)Ra, (222)Rn, (238)U, major ion concentrations, and physico-chemical parameters were also measured. Concentrations values ranged from <0.002 to 0.492 Bq l(-1) for (226)Ra, from <0.01 to 1.50 Bq l(-1) for (228)Ra and from < 1.0 x 10(-4) to 8.0 x 10(-2) Bq l(-1) for (238)U. Detectable (222)Rn concentrations (>3 Bq l(-1)) were found only in two samples. The spatial distribution of Ra concentration delineated one distinct area and some hot spots with high Ra concentration. Low pH value is the most important water parameter linked to high radium concentration. This is probably related to limited adsorption of radium on soil ferric oxides and hydroxides at low pH range. There was a significant correlation between uranium concentrations and electrical conductivity values, and also between uranium concentrations and concentrations of Ca, Mg, Na, K, and Cl, indicating sea water impact. Uranium concentrations were lower than maximum contaminant level for drinking water, whereas 17 out of the 88 ground water samples had levels of radium that exceeded the maximum contaminant level for tap water. The total annual effective dose for adult due to the water consumption reaches values up to 0.8 mSv.

  2. ESR dating of Smilodon populator from Toca de Cima dos Pilão, Piauí, Brazil.

    PubMed

    Kinoshita, Angela; Mollemberg, Michelle; Santana, William; G Figueiredo, Ana Maria; Guidon, Niede; Fátima da Luz, Maria de; Guérin, Claude; Baffa, Oswaldo

    2017-02-01

    Smilodon is a genus of big cats that lived from the early to the late Pleistocene in regions extending from North to South America. The fossil records of the "saber-toothed cats" are uneven, with some taxa being quite abundant in certain regions. In Brazil, Smilodon populator is a well-known species whose remains, although scarce in comparison to other large mammals, are found all across the country. In particular, there are multiple records of this species in the region of the Serra da Capivara National Park. This area was home to a rich Pleistocene-Holocene fauna, including many mammals. Here, we report on the Electron Spin Resonance dating of a Smilodon populator tooth found in "Toca de Cima dos Pilão", located in the surroundings of the Serra da Capivara National Park. The equivalent dose found after exponential fitting of dose-response curve was (2.7±0.3)x10(2)Gy. Neutron Activation Analysis was used to determine the concentration of radioisotopes present in the sample and in the sediment to calculate the internal and external dose rates. The result of age found is 93±9ka, which confirmed the presence of this species in Serra da Capivara National Park in the late Pleistocene.

  3. Brief communication: "Zuzu" strikes again--morphological affinities of the early holocene human skeleton from Toca dos Coqueiros, Piaui, Brazil.

    PubMed

    Hubbe, Mark; Neves, Walter A; do Amaral, Heleno Licurgo; Guidon, Niéde

    2007-10-01

    The Serra da Capivara National Park in northeastern Brazil is one of the richest archaeological regions in South America. Nonetheless, so far only two paleoindian skeletons have been exhumed from the local rockshelters. The oldest one (9870 +/- 50 BP; CAL 11060 +/- 50), uncovered in Toca dos Coqueiros and known as "Zuzu," represents a rare opportunity to explore the biological relationships of paleoindian groups living in northeastern Brazil. As previously demonstrated, South and Central America Paleoindians present skull morphology distinct from the one found nowadays in Amerindians and similar to Australo-Melanesians. Here we test the hypothesis that Zuzu shows higher morphological affinity with Paleoindians. However, Zuzu is a controversial skeleton since previous osteological assessments have disagreed on several aspects, especially regarding its sex. Thus, we compared Zuzu to males and females independently. Morphological affinities were assessed through clustering of principal components considering 18 worldwide populations and through principal components analysis of the individual dispersion of five key regions for America's settlement. The results obtained do not allow us to refute the hypothesis, expanding the known geographical dispersion of the Paleoindian morphology into northeast Brazil. To contribute to the discussion regarding Zuzu's sex, a new estimation is presented based on visual inspection of cranial and post-cranial markers, complemented by a discriminant analysis of its morphology in relation to the paleoindian sample. The results favor a male classification and are consistent with the mortuary offerings found in the burial, yet do not agree with a molecular determination.

  4. Power-efficiency trade-off due to density of states (DOS) distortion in a molecular thermoelectric system

    NASA Astrophysics Data System (ADS)

    Desouza, Priyanka; Muralidharan, Bhaskaran

    2013-03-01

    The issue of how a distortion in the electronic DOS affects nanoscale thermoelectric performance is addressed within an ``electrical engineering'' perspective. This view point is based on the direct evaluation of the overall efficiency and power from device current-voltage characteristics and gives a more complete picture of the thermoelectric performance in comparison to the traditional ``figure of merit'' based material science approach. We use representative examples from molecular conduction to study the trade-off between maximum efficiency and the maximum power generated within the set up. The trade-off is maximum for the well known example of a sharply resonant molecular level which represents the ultimate distortion in the electronic density of states. As the distortion is reduced via contact induced broadening, we obtain a smaller trade-off between maximum power and efficiency. We then present the effects of self consistent charging, contact induced asymmetry and the HOMO-LUMO gap on the thermoelectric performance. In all cases we compare our non-equilibrium calculations with zT calculations, and our results depict that zT is not the sole metric for the assessment of nanoscale thermoelectric performance.

  5. Holocene history of a lake filling and vegetation dynamics of the Serra Sul dos Carajás, southeast Amazonia.

    PubMed

    Guimarães, José T F; Sahoo, Prafulla K; Souza-Filho, Pedro W M; Figueiredo, Mariana M J Costa DE; Reis, Luiza S; Silva, Marcio S DA; Rodrigues, Tarcísio M

    2017-07-24

    Down-core changes in sedimentary facies, elemental geochemistry, pollen, spore, δ13C, δ15N and radiocarbon records from a filled lake, named R4, of the Serra Sul dos Carajás were used to study the relationship between the paleomorphological and paleoecological processes and their significance for Holocene paleoclimatology of the southeast Amazonia. The sediment deposition of the R4 lake started around 9500 cal yr BP. Increase of detrital components from 9500 to 7000 cal yr BP suggests high weathering of surrounding catchment rocks and soils, and deposition into the lake basin under mudflows. At that time, montane savanna and forest formation were already established suggesting predominance of wet climate. However, from 7000 to 3000 cal yr BP, a decline of detrital input occurred. Also, forest formation and pteridophytes were declined, while palms and macrophytes were remained relatively stable, indicating that water levels of the lake is likely dropped allowing the development of plants adapted to subaerial condition under drier climate conditions. After 3000 cal yr BP, eutrophication and low accommodation space lead to high lake productivity and the final stage of the lake filling respectively, and forest formation may has acquired its current structure, which suggests return of wetter climate conditions.

  6. Usefulness of thallium-201 chloride single photon emission computed tomography for the preoperative diagnosis of fourth ventricle meningioma--case report.

    PubMed

    Ooigawa, Hidetoshi; Miyazawa, Takahito; Otani, Naoki; Fukui, Shinji; Nawashiro, Hiroshi; Shima, Katsuji

    2004-12-01

    A 51-year-old woman presented with a fourth ventricle meningioma manifesting as a 2-week history of dizziness and vomiting. Computed tomography (CT) and magnetic resonance (MR) imaging revealed a round mass lesion in the fourth ventricle. Thallium-201 chloride single photon emission computed tomography (201TlCl SPECT) showed high and rapid uptake on the early image and rapid washout on the delayed image. The preoperative diagnosis of meningioma could be established based on these findings. Total removal of the tumor was successfully performed. 201TlCl SPECT is useful for the preoperative diagnosis of fourth ventricle meningioma combined with CT, MR imaging, and angiography.

  7. Multifocal inflammatory leukoencephalopathy: use of thallium-201 SPECT and proton MRS.

    PubMed Central

    Hwang, Yang Ha; Suh, Chung Kyu; Park, Sung Pa

    2003-01-01

    In a patient receiving 5-fluorouracil and levamisole, neurologic deficits suggest the cerebral demyelinating syndrome as a differential diagnosis. The authors report a patient diagnosed as multifocal inflammatory leukoencephalopathy for which thallium-201 (201Tl) single photon emission computed tomography (SPECT) and proton magnetic resonance spectroscopy (MRS) were employed as noninvasive diagnostic tools. 201Tl SPECT study was negative and proton MRS showed an increase of choline and lactate and well preserved N-acetylaspartate. These findings support histopathologic findings of multifocal inflammatory leukoencephalopathy revealing demyelination with relative axonal sparing in the patient. PMID:12923348

  8. Dos Amigos... (Two Friends...).

    ERIC Educational Resources Information Center

    Aguilar, Rosalie M.

    Intended for supplementary reading material for Spanish speaking children in elementary grades, this illustrated Spanish text was developed by students in the Bilingual Teacher Aide Program at Mesa Community College. Both language and content have been controlled to provide linguistically and culturally sensitive material relevant to the…

  9. [Hypertension in women: study in mothers of students from Jaboatão dos Guararapes, Pernambuco, Brazil].

    PubMed

    Teodósio, Marta Regueira; Freitas, Clara Lúcia C de; Santos, Naíde Teodósio Valois; Oliveira, Eliane da Cunha Mendonça de

    2004-01-01

    The purpose of this research was to study the prevalence of hypertension in apparently healthy women community with a view preparing a program for primary prevention of hypertension. The population survey involved a representative sample of mothers of 126.800 students enrolled at schools of Jaboatão dos Guararapes, Pernambuco, Brasil. The population size (1.273 students) was selected from a 5% +/- 2% expected frequency of the hypertension in children with a confidence level of 99.9%. This study comprised 21 schools and a random sample of 986 mothers of 1.601 students). Two blood pressure measurements separated by 2 minutes were carried out in the schools on two subsequent visits. The corporal mass index was determined in 893 mothers. In a group of 671 mothers, a midstream urine specimen was collected and the dip - stick was used to assess the presence of urinary abnormalities. The prevalence of the hypertension was 27.7% and it was significantly higher (p<0.01) in overweight (28.5%) and obese women (57%) than normal weight women (14%) and underweight women (12%). There was significant difference regarding the presence of glucosuria between the hypertensives and the normotensives women (3% and 0%, respectively). In a group of 62 hypertensives women with followup at 3 to 12 month interval, the blood pressure has been controlled in 13 (21%) and remains below the initial hypertensive stage in 27 (43.5%). The prevalence of hypertension (27,7%) do agree with the data in the literature concerning hypertension in women (26%), showing a higher tendency in overweight and obese women. We are continuing the followup of the hypertensive women as well as developing a community program for primary prevention of hypertension in the target population.

  10. En la búsqueda de características en eyecciones coronales de masa que discriminen entre dos paradigmas físicos en modelos de ECMs

    NASA Astrophysics Data System (ADS)

    Paissan, G.; Stenborg, G.; Rovira, M.

    Se conocen tres diferentes fenómenos de gran escala que ocurren en la atmósfera solar, denominados eyecciones coronales de masa (ECMs), protuberancias eruptivas y grandes fulguraciones de dos bandas. Estos fenómenos están estrechamente relacionados y podrían ser distintas manifestaciones de un único proceso físico. Las ECMs son definidas como eyecciones de gran escala de masa y flujo magnético desde la baja corona al espacio interplanetario. Desde su descubrimiento en los '70, muchos modelos han sido propuestos para explicar su origen y evolución. La explicación física de las ECMs es un tema de debate intenso. No obstante, los modelos pueden sintetizarse en dos grandes grupos: 1) los modelos de inyección de flujo y 2) los modelos de almacenamiento y liberación. En este trabajo, se presentan los estudios realizados con una serie de eventos observados con el coronógrafo MICA (Mirror Coronograph for Argentina), el telescopio en H-alfa HASTA (H-alpha Solar Telescope for Argentina) y los coronógrafos C2 y C3 de la sonda SOHO (Solar and Heliospheric Observatory). Los eventos que pudieron ser identificados como ECMs son contrastados dentro del esquema de los dos paradigmas teóricos propuestos.

  11. The petrochemistry of the auriferous, volcanosedimentary Riacho dos Machados Group, Central-eastern Brazil: geotectonic implications for shear-hosted gold mineralization

    NASA Astrophysics Data System (ADS)

    da Fonseca, E.; Lobato, L. M.; Baars, F. J.

    1997-12-01

    The Ouro Fino Gold Deposit at the Riacho dos Machados Mine is located in the Araçuaí Fold Belt at the eastern margin of the São Francisco Craton. The gold is shear zone-hosted and associated principally with a sulphide-bearing, quartzmuscovite schist, derived from the hydrothermal alteration of pelitic and quartzofeldspathic schists of the Riacho dos Machados Group (RMG). Along the shear zones, mineral associations typical of the amphibolite facies are progressively altered to assemblages typical of the greenschist facies. It has become evident from the studies that the process of segregation and concentration of chemical elements and minerals is the very process of mineralization, involving the concentration of Au. The RMG comprises ultramafic, mafic and acid metavolcanic rocks intercalated in a sequence of metapelites. The metapelites have textures and geochemistry compatible with greywackes. The dacitic and mafic/ultramafic rocks are of calc-alkaline and tholeiitic subalkaline association, respectively. The RMG probably formed within a continental volcanic arc. The thrust faults that establish the regional architecture, and which host the Riacho dos Machados gold mineralization, are related to a continental collision of unknown age between the precursor to the São Francisco Craton and the Guanambi-Correntina Block.

  12. Queda dos homicídios em São Paulo, Brasil: uma análise descritiva

    PubMed Central

    Peres, Maria Fernanda Tourinho; Vicentin, Diego; Nery, Marcelo Batista; de Lima, Renato Sérgio; de Souza, Edinilsa Ramos; Cerda, Magdalena; Cardia, Nancy; Adorno, e Sérgio

    2012-01-01

    Objetivo Descrever a evolução da mortalidade por homicídios no Município de São Paulo segundo tipo de arma, sexo, raça ou cor, idade e áreas de exclusão/inclusão social entre 1996 e 2008. Métodos Estudo ecológico de série temporal. Os dados sobre óbitos ocorridos no Município foram coletados da base de dados do Programa de Aprimoramento das Informações sobre Mortalidade, seguindo a Classificação Internacional de Doenças, Décima Revisão (CID-10). Foram calculadas as taxas de mortalidade por homicídio (TMH) para a população total, por sexo, raça ou cor, faixa etária, tipo de arma e área de exclusão/inclusão social. As TMH foram padronizadas por idade pelo método direto. Foram calculados os percentuais de variação no período estudado. Para as áreas de exclusão/inclusão social foram calculados os riscos relativos de morte por homicídio. Resultados As TMH apresentaram queda de 73,7% entre 2001 e 2008. Foi observada redução da TMH em todos os grupos analisados, mais pronunciada em homens (−74,5%), jovens de 15 a 24 anos (−78,0%) e moradores de áreas de exclusão social extrema (−79,3%). A redução ocorreu, sobretudo, nos homicídios cometidos com armas de fogo (−74,1%). O risco relativo de morte por homicídio nas áreas de exclusão extrema (tendo como referência áreas com algum grau de exclusão social) foi de 2,77 em 1996, 3,9 em 2001 e 2,13 em 2008. Nas áreas de alta exclusão social, o risco relativo foi de 2,07 em 1996 e 1,96 em 2008. Conclusões Para compreender a redução dos homicídios no Município, é importante considerar macrodeterminantes que atingem todo o Município e todos os subgrupos populacionais e microdeterminantes que atuam localmente, influenciando de forma diferenciada os homicídios com armas de fogo e os homicídios na população jovem, no sexo masculino e em residentes em áreas de alta exclusão social. PMID:21390415

  13. 2.3 Å X-ray Structure of the Heme-Bound GAF Domain of Sensory Histidine Kinase DosT of Mycobacterium tuberculosis†

    PubMed Central

    Podust, Larissa M.; Ioanoviciu, Alexandra; Ortiz de Montellano, Paul R.

    2009-01-01

    Mycobacterium tuberculosis responds to the changes in environmental conditions through a two-component signaling system that detects reduced O2 tension and NO and CO exposures via the heme-binding GAF domains of two sensory histidine kinases, DosT and DevS, and the transcriptional regulator DosR. We report the first x-ray structure of the DosT heme-bound GAF domain (GAFDosT) in both oxy and deoxy forms determined to a resolution of 2.3 Å. In GAFDosT, heme binds in an orientation orthogonal to that in the PAS domains via a highly conserved motif including invariant H147 as a proximal heme axial ligand. On the distal side, invariant Y169 is in stacking interactions with the heme with its long axis parallel and the plane of the ring orthogonal to the heme plane. In one of the two protein monomers in an asymmetric unit, O2 binds as a second axial ligand to the heme iron, and is stabilized via an H-bond to the OH-group of Y169. The structure reveals two small tunnel-connected cavities and a pore on the protein surface that suggest a potential route for O2 access to the sensing pocket. The limited conformational differences observed between differently heme iron-ligated GAFDosT monomers in the asymmetric unit may result from crystal lattice limitations since atmospheric oxygen binding likely occurs in the crystal as a result of x-ray induced Fe3+ photoreduction during diffraction data collection. Determination of the GAFDosT structure sets up a framework in which to address ligand-recognition, discrimination, and signal propagation schemes in the heme-based GAF domains of biological sensors. PMID:18980385

  14. [Species from genus Eimeria observed in domestic rabbit (Oryctolagus cuniculus) feces raised at the Municipality of Campos dos Goytacazes in the State of Rio de Janeiro, Brazil].

    PubMed

    de Almeida, Adriana J; Mayen, Friederike L; de Oliveira, Francisco C R

    2006-01-01

    This study was designed to identify species of the genus Eimeria from eleven rabbit meat breeders from Campos dos Goytacazes. Fecal samples were collected from rabbits with different health conditions and consintence of feces. The following species of Eimeria were identified: E. perforans; E. magna; E. coecicola; E. irresidua; E. media; E. flavescens; E. nagpurensis; E. intestinalis, E. exigua and E. stiedae. Parasites from this genus were detected in 81.82% (9) of the rabbit meat production sites, regardless of the management and hygiene conditions. In all cases the infection was always caused from more than one species of Eimeria.

  15. Dipyridamole thallium-201 scintigraphy as a preoperative screening test. A reexamination of its predictive potential. Study of Perioperative Ischemia Research Group

    SciTech Connect

    Mangano, D.T.; London, M.J.; Tubau, J.F.; Browner, W.S.; Hollenberg, M.; Krupski, W.; Layug, E.L.; Massie, B. )

    1991-08-01

    The authors examined the value of dipyridamole thallium-201 (201Tl) scintigraphy as a preoperative screening test for perioperative myocardial ischemia and infarction. They prospectively studied 60 patients undergoing elective vascular surgery. They performed 201Tl scintigraphy preoperatively and blinded all treating physicians to the results. Historical, clinical, laboratory, and physiological data were gathered throughout hospitalization. Myocardial ischemia was assessed during the intraoperative period using continuous 12-lead electrocardiography (ECG) and transesophageal echocardiography (TEE) and during the postoperative period using continuous two-lead ambulatory ECG. Adverse cardiac outcomes (cardiac death, myocardial infarction, unstable angina, severe ischemia, or congestive heart failure) were assessed daily throughout hospitalization. Twenty-two patients (37%) had defects that improved or reversed on delayed scintigrams (redistribution defects), 18 (30%) had persistent defects, and 20 (33%) had no defects on 201Tl scintigraphy. There was no association between redistribution defects and adverse cardiac outcomes: 54% (seven of 13) of adverse outcomes occurred in patients without redistribution defects, and the risk of an adverse outcome was not significantly increased in patients with redistribution defects. Consistent with these findings, there was also no association between redistribution defects and perioperative ischemia: 54% (19 of all 35) of perioperative ECG and TEE ischemic episodes and 58% (14 of 24) of severe ischemic episodes occurred in patients without redistribution defects. The sensitivity of 201Tl scintigraphy for perioperative ischemia and adverse outcomes ranged from 40% to 54%, specificity from 65% to 71%, positive predictive value from 27% to 47% and negative predictive value from 61% to 82%.

  16. Use of thallium-201 redistribution scintigraphy in the preoperative differentiation of reversible and nonreversible myocardial asynergy.

    PubMed

    Rozanski, A; Berman, D S; Gray, R; Levy, R; Raymond, M; Maddahi, J; Pantaleo, N; Waxman, A D; Swan, H J; Matloff, J

    1981-11-01

    Thallium-201 (201Tl) redistribution scintigraphy might differentiate reversibly from nonreversibly asynergic myocardial segments and thus predict the response of these segments to coronary artery bypass grafting (CABG). To test this hypothesis, 25 consecutive patients undergoing CABG, preoperative stress-redistribution 201Tl scintigraphy, and both pre- and postoperative resting equilibrium radionuclide ventriculography were evaluated. For both types of scintigraphic study, each patient was imaged in the same three views. Because of the effects of CABG on septal motion, this region was considered separately. Postoperative improvement was noted in 54% of 72 preoperative asynergic segments. Improvement was common not only in hypokinetic but also in akinetic and dyskinetic segments, and occurred in a similar proportion of studies performed early (less than 2 weeks) or late (3-6 months) after CABG. Thallium-201 redistribution scintigraphy was highly predictive of the pattern of postoperative asynergy: The redistribution pattern was normal in 90% of segments with reversible asynergy and abnormal in 76% of segments with nonreversible asynergy. The presence or absence of pathologic Q waves was less sensitive in this differentiation. Septal segments, however, frequently demonstrated abnormal wall motion postoperatively, despite normal 201Tl redistribution scintigraphy. Resting left ventricular ejection fraction (LVEF) was generally unchanged postoperatively, but in some patients with multiple areas of reversible asynergy it did improve. Thus, 201Tl redistribution scintigraphy appears to reliably distinguish viable from nonviable asynergic myocardial zones, and predicts the response of these segments to CABG.

  17. Upward creep of the heart: A frequent source of false-positive reversible defects during thallium-201 stress-redistribution SPECT

    SciTech Connect

    Friedman, J.; Van Train, K.; Maddahi, J.; Rozanski, A.; Prigent, F.; Bietendorf, J.; Waxman, A.; Berman, D.S. )

    1989-10-01

    A new cause of artifactual {sup 201}Tl defects on single photon emission computed tomography (SPECT) termed upward creep of the heart is described. In 102 consecutive patients undergoing {sup 201}Tl SPECT, 30 (29%) demonstrated upward creep defined by an upward movement of the heart of greater than or equal to 2 pixels during acquisition. In 45 consecutive patients with a less than 5% likelihood of coronary artery disease, 17 (38%) had upward creep. Of these nine had reversible {sup 201}Tl defects localized to the inferior and basal inferoseptal walls, while none of the 28 without upward creep had defects. The 17 low likelihood patients with upward creep had longer exercise duration and higher peak heart rate than those without upward creep. In five additional low likelihood patients with upward creep in whom imaging was immediately repeated, the upward creep pattern disappeared on the repeated images. After we changed our test protocol to begin imaging 15 min postexercise, only five (14%) of 36 low likelihood patients tested demonstrated upward creep. Upward creep is probably related to a transient increase in mean total lung volume early following exhaustive exercise, resulting in a mean lower position of the diaphragm (and thus the heart) at the beginning of imaging. The frequency of this source of false-positive {sup 201}Tl studies can be reduced by delaying SPECT acquisition until 15 min postexercise.

  18. Thallium 201 Exercise Scintigraphy for Detection of Multivessel Coronary Artery Disease After Transmural Myocardial Infarction

    PubMed Central

    Ahmadpour, Hedayatolah; Siegel, Michael E.; Colletti, Patrick; Haywood, L. Julian

    1984-01-01

    Fifty patients with prior transmural myocardial infarction were studied with cardiac catheterization, coronary angiography, and thallium 201 exercise perfusion scintigraphy. Obstructive coronary disease involved two or three vessels in 37 patients. The sensitivity of a positive electrocardiographic test during exercise for detecting multivessel coronary disease was only 40 percent (15/37), and the sensitivity of a reversible defect on 201Tl perfusion scintigraphy was 48 percent (18/37). The combination of exercise testing and 201Tl scintigraphy detected multivessel coronary disease in 75 percent (28/37) (P < .05). New perfusion defects occurred in 61 percent (13/21) of patients with inferior myocardial infarction and multivessel coronary disease whereas it occurred in only 35 percent (5/14) of patients with prior anterior infarction and multivessel coronary disease (P < .05). 201Tl exercise perfusion scintigraphy appears to be more sensitive for detecting significant multivessel coronary disease in the presence of previous inferior infarction compared with previous anterior infarction. Combined graded exercise testing and 201Tl perfusion scintigraphy can reliably detect the presence of significant multivessel coronary disease after transmural myocardial infarction. ImagesFigure 3 PMID:6512876

  19. Comparison of thallium-201 SPET and CT/MRI in the detection of residual/recurrent squamous cell carcinoma of the oral cavity.

    PubMed

    Lee, Jong-Kang; Tyan, Yeu-Sheng; Huang, Wen-Sheng

    2004-04-01

    This study was designed to compare the effectiveness of thallium-201 single-photon emission tomography (SPET) and conventional imaging, comprising computed tomography (CT) and magnetic resonance imaging (MRI), in the detection of residual/recurrent squamous cell carcinoma (SCC) of the oral cavity. Thirty-two patients with clinically suspected recurrent SCC of the oral cavity were recruited. All patients underwent (201)Tl SPET and CT or MRI within 2 weeks. The final diagnoses were based on the histology of the biopsy specimen. (201)Tl SPET and CT/MRI both accurately detected 17 of 18 residual/recurrent tumours. CT/MRI yielded eight false-positive studies, whereas (201)Tl SPET successfully excluded all tumours. The sensitivity, specificity, positive and negative predictive values and accuracy of (201)Tl SPET for the detection of recurrent oral SCC were 94%, 100%, 100%, 93% and 97%, respectively. The sensitivity, specificity, positive and negative predictive values and accuracy of CT/MRI for the detection of recurrent oral SCC were 94%, 43%, 68%, 86% and 72%, respectively. Thallium-201 SPET is more accurate than conventional imaging (CT or MRI) in differentiating residual/recurrent oral SCC from post-therapy changes.

  20. Evaluation of penetration and scattering components in conventional pinhole SPECT: phantom studies using Monte Carlo simulation

    NASA Astrophysics Data System (ADS)

    Deloar, Hossain M.; Watabe, Hiroshi; Aoi, Toshiyuki; Iida, Hidehiro

    2003-04-01

    In quantitative pinhole SPECT, photon penetration through the collimator edges (penetration), and photon scattering by the object (object scatter) and collimator (collimator scatter) have not been investigated rigorously. Monte Carlo simulation was used to evaluate these three physical processes for different tungsten knife-edge pinhole collimators using uniform, hotspot and donut phantoms filled with 201Tl, 99mTc, 123I and 131I solutions. For the hotspot phantom, the penetration levels with respect to total counts for a 1 mm pinhole aperture were 78%, 28% and 23% for 131I, 123I and 99mTc, respectively. For a 2 mm aperture, these values were 65% for 131I, 16% for 123I and 12% for 99mTc. For all pinholes, 201Tl penetration was less than 4%. The evaluated scatter (from object and collimator) with a hotspot phantom for the 1 mm pinhole was 24%, 16%, 18% and 13% for 201Tl, 99mTc, 123I and 131I, respectively. Summation of the object and collimator scatter for the uniform phantom was approximately 20% higher than that for the hotspot phantom. Significant counts due to penetration and object and collimator scatter in the reconstructed image were observed inside the core of the donut phantom. The collimator scatter can be neglected for all isotopes used in this study except for 131I. Object scatter correction for all radionuclides used in this study is necessary and correction for the penetration contribution is necessary for all radionuclides but 201Tl.

  1. Diagnostic value of Thallium-201 scintigraphy in differentiating malignant bone tumors from benign bone lesions.

    PubMed

    Inai, Ryota; Shinya, Takayoshi; Tada, Akihiro; Sato, Shuhei; Fujiwara, Tomohiro; Takeda, Ken; Kunisada, Toshiyuki; Yanai, Hiroyuki; Ozaki, Toshifumi; Kanazawa, Susumu

    2015-10-01

    This retrospective study aims to evaluate the diagnostic capacity of thallium-201 (201Tl) scintigraphy for differentiating malignant bone tumors from benign bone lesions. Between January 2006 and December 2012, 279 patients with bone lesions (51 malignant and 228 benign) underwent 201Tl scintigraphy before treatment. To evaluate 201Tl uptake, we investigated tumor-to-background contrast (TBC) as well as TBC washout rate (WR). The differences of TBC on early and delayed images and WR were estimated by the Mann-Whitney U test. Receiver operating characteristic (ROC) analyses were used to determine the cut-off TBC values for differentiating malignant bone tumors from benign bone lesions. There were statistically significant differences in median TBC between malignant tumors and benign lesions. These differences occurred for early imaging (1.57 vs. 0.09, p < 0.001) as well as for delayed imaging (0.83 vs. 0.07, p < 0.001). However, there was no statistical difference in WR between malignant tumors and benign lesions (44 vs. 43 %, NS). The chosen TBC cut-off value was 0.68 for early imaging and 0.38 for delayed imaging. Using these cut-off values, the prediction of malignancy had a 77 % sensitivity, 74 % specificity, and 75 % accuracy for early imaging and an 80 % sensitivity, 76 % specificity, and 77 % accuracy for delayed imaging. 201Tl scintigraphy may have the ability to distinguish malignant bone tumors from benign bone lesions.

  2. 10 CFR 30.71 - Schedule B.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...) 100 Tellurium 131m (Te 131m) 10 Tellurium 132 (Te 132) 10 Terbium 160 (Tb 160) 10 Thallium 200 (Tl 200) 100 Thallium 201 (Tl 201) 100 Thallium 202 (Tl 202) 100 Thallium 204 (Tl 204) 10 Thulium 170 (Tm 170...

  3. 10 CFR 30.71 - Schedule B.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...) 100 Tellurium 131m (Te 131m) 10 Tellurium 132 (Te 132) 10 Terbium 160 (Tb 160) 10 Thallium 200 (Tl 200) 100 Thallium 201 (Tl 201) 100 Thallium 202 (Tl 202) 100 Thallium 204 (Tl 204) 10 Thulium 170 (Tm 170...

  4. 10 CFR 30.71 - Schedule B.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...) 100 Tellurium 131m (Te 131m) 10 Tellurium 132 (Te 132) 10 Terbium 160 (Tb 160) 10 Thallium 200 (Tl 200) 100 Thallium 201 (Tl 201) 100 Thallium 202 (Tl 202) 100 Thallium 204 (Tl 204) 10 Thulium 170 (Tm 170...

  5. 10 CFR 30.71 - Schedule B.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...) 100 Tellurium 131m (Te 131m) 10 Tellurium 132 (Te 132) 10 Terbium 160 (Tb 160) 10 Thallium 200 (Tl 200) 100 Thallium 201 (Tl 201) 100 Thallium 202 (Tl 202) 100 Thallium 204 (Tl 204) 10 Thulium 170 (Tm 170...

  6. Thallium 201 and Gallium 67 uptake in malignant fibrous histiocytoma of the heart

    SciTech Connect

    Minamiji, K.; Yamasaki, T.; Nakao, M.; Furumoto, M.; Yoshida, Y.

    1986-02-01

    A patient with malignant fibrous histiocytoma of the heart is described who was initially presented with a left atrial tumor. Subsequent /sup 201/Tl and /sup 67/Ga scintigraphy showed massive uptake of the tracers by the tumor and the pattern of uptake was thought to reflect underlying necrosis and hemorrhage within the tumor.

  7. Thallium-201 imaging in a patient with mid-ventricular hypertrophic obstructive cardiomyopathy

    SciTech Connect

    Wakasugi, S.; Shibata, N.; Kobayashi, T.; Fudemoto, Y.; Hasegawa, Y.; Nakano, S.

    1988-10-01

    Findings specific to mid-ventricular hypertrophic obstructive cardiomyopathy were obtained in a patient by means of /sup 201/Tl planar myocardial scintigraphy. Namely, a myocardial band-like image dividing the left ventricle into two chambers was clearly shown. This was identified as hypertrophic muscle with sphincter-like muscular stenosis at the mid portion of the left ventricle.

  8. ²⁰¹Tl⁺-labelled Prussian blue nanoparticles as contrast agents for SPECT scintigraphy.

    PubMed

    Perrier, M; Busson, M; Massasso, G; Long, J; Boudousq, V; Pouget, J-P; Peyrottes, S; Perigaud, Ch; Porredon-Guarch, C; de Lapuente, J; Borras, M; Larionova, J; Guari, Y

    2014-11-21

    Prussian blue (PB) and its analogues on the nanometric scale are exciting nano-objects that combine the advantages of molecular-based materials and nanochemistry. Herein, we demonstrate that ultra-small PB nanoparticles of 2-3 nm can be easily labelled with radioactive (201)Tl(+) to obtain new nanoprobes as radiotracers for 201-thallium-based imaging.

  9. False-negative dipyridamole-thallium-201 myocardial imaging after caffeine infusion

    SciTech Connect

    Smits, P.; Corstens, F.H.; Aengevaeren, W.R.; Wackers, F.J.; Thien, T. )

    1991-08-01

    The vasodilator effect of intravenously administered dipyridamole may be caused by an increase in endogenous plasma adenosine levels. The authors evaluated the effect of caffeine, an adenosine receptor antagonist, on the diagnostic results of dipyridamole-201Tl myocardial imaging in eight patients with coronary artery disease. Caffeine infusion significantly attenuated the dipyridamole-induced fall in blood pressure and the accompanied increase in heart rate. The infusion of dipyridamole alone resulted in chest pain and ST-segment depressions on the electrocardiogram in four patients, whereas none of these problems occurred when the tests were repeated after caffeine. In six of eight patients, caffeine was responsible for false-negative dipyridamole-201Tl tests. Semiquantitive scores of the dipyridamole-induced 201Tl perfusion defects were decreased by caffeine from 9.0 {plus minus} 0.9 to 2.0 {plus minus} 1.1 points (p less than 0.05). Computerized analysis revealed a caffeine-mediated reduction in the percent reversibility of the images from 46% {plus minus} 16% to 6% {plus minus} 10% (p less than 0.05). They conclude that the use of caffeinated products prior to dipyridamole-201Tl testing may be responsible for false-negative findings.

  10. Ribose facilitates thallium-201 redistribution in patients with coronary artery disease

    SciTech Connect

    Perlmutter, N.S.; Wilson, R.A.; Angello, D.A.; Palac, R.T.; Lin, J.; Brown, B.G. )

    1991-02-01

    To investigate whether i.v. infusion of ribose, an adenine nucleotide precursor, postischemia facilitates thallium-201 (201Tl) redistribution and improves identification of ischemic myocardium in patients with coronary artery disease (CAD), 17 patients underwent two exercise 201Tl stress tests, performed 1-2 wk apart. After immediate postexercise planar imaging, patients received either i.v. ribose (3.3 mg/kg/min x 30 min) or saline as a control. Additional imaging was performed 1 and 4 hr postexercise. Reversible defects were identified by count-profile analysis. Significantly more (nearly twice as many) reversible 201Tl defects were identified on the post-ribose images compared to the post-saline (control) images at both 1 and 4 hr postexercise (p less than 0.001). Quantitative analyses of the coronary arteriogram was available in 13 patients and confirmed that the additional reversible defects were in myocardial regions supplied by stenosed arteries. We conclude that ribose appears to facilitate 201Tl redistribution in patients with CAD and enhances identification of ischemic myocardium.

  11. Hepatitis A seroprevalence in public school children in Campos dos Goytacazes, Rio de Janeiro State, Brazil, prior to the introduction of the hepatitis A universal childhood vaccination.

    PubMed

    Kury, Charbell Miguel; Pinto, Marcelo Alves; Silva, Jaquelline Pereira da; Cruz, Oswaldo Gonçalves; Vitral, Claudia Lamarca

    2016-11-01

    This cross-sectional study was carried out between August 2011 and July 2012 in the city of Campos dos Goytacazes in Rio de Janeiro State, Brazil. Dried blood spot samples were collected on filter paper from 919 individuals between the ages of 1 and 19 and were tested for antibodies against the hepatitis A virus (anti-HAV). The total prevalence was 20.7%, while 94.7% of children under the age of 5 were found to be susceptible to HAV infection. The prevalence of anti-HAV increased with age, reaching 33.3% among individuals aged between 15 and 19, thereby indicating that this municipality has a low level of endemicity for hepatitis A. Age, non-white skin color, accustomed to swimming in the river and more than five people living at home were the factors that were associated with an increase in the chance of a positive anti-HAV result. Mother's education level (secondary or tertiary) was considered a protective factor for HAV infection. The data obtained showed that a large proportion of the children from Campos dos Goytacazes were at risk of HAV infection, which should be minimized with the introduction of the vaccination program against hepatitis A that was launched in the municipality in 2011.

  12. Católicos, fidelidade conjugal e AIDS: entre a cruz da doutrina moral e as espadas do cotidiano sexual dos adeptos1

    PubMed Central

    Rios, Luis Felipe; de Aquino, Francisca Luciana; Muñoz-Laboy, Miguel; Oliveira, Cinthia; Parker, Richard

    2009-01-01

    Neste artigo discutimos a visão da Igreja Católica sobre sexualidade na interface com a epidemia do HIV/AIDS. Nossa reflexão está embasada em pesquisa etnográfica que envolveu dois meses de observação participante do cotidiano de católicos de um bairro popular da Região Metropolitana do Recife, além de contar com entrevistas a onze dos leigos engajados nos serviços religiosos da igreja do bairro e a oito sacerdotes que realizam seus trabalhos religiosos em outras localidades. Nelas abordamos diferentes temáticas relacionadas ao enfrentamento da epidemia da AIDS. Nesse contexto, conjugalidade e fidelidade se afiguram como importantes analisadores de como aqueles lidam com a epidemia, em uma variedade de re-descrições práticas e de re-interpretações conceptuais das assertivas do discurso moral religioso – ainda que, muitos impasses permaneçam em aberto em termos das prerrogativas da Igreja e seus possíveis rebatimentos na saúde sexual dos adeptos. PMID:21765650

  13. Detection of IgG1 antibodies against Mycobacterium tuberculosis DosR and Rpf antigens in tuberculosis patients before and after chemotherapy.

    PubMed

    Mattos, Ana Márcia Menezes; Chaves, Alexandre Silva; Franken, Kees L M C; Figueiredo, Bárbara Bruna Muniz; Ferreira, Ana Paula; Ottenhoff, Tom H M; Teixeira, Henrique Couto

    2016-01-01

    Diagnosis of tuberculosis (TB) remains challenging. Serum IgG1 antibodies against Mycobacterium tuberculosis active growth phase antigens (ESAT-6/CFP-10, Rv0717 and Rv3353), DosR regulon-encoded proteins (Rv1733, Rv1737, Rv2628 and Rv2029), and resuscitation-promoting factors (Rv0867 and Rv2389) were evaluated in TB patients using ELISA. Active TB patients showed elevated levels of IgG1 antibodies against ESAT-6/CFP-10, Rv0717, Rv3353, Rv1733, Rv2628, Rv2029 and Rv0867 in comparison to healthy controls (p < 0.001). These levels remained high after the initiation of treatment, while responses to Rv0717 and Rv1733 peaked early during treatment. IgG1 responses to ESAT-6/CFP-10, Rv3353, Rv2628, Rv2029 and Rv0867 declined to control levels after the completion of 6 months chemotherapy. ROC analysis confirmed the good diagnostic performance of Rv0717, Rv1733, Rv3353, Rv2628, Rv2029 and Rv0867antigens. These data suggest that detecting IgG1 antibodies against M. tuberculosis antigens, including DosR and Rpf proteins, may represent an additional tool in the diagnosis of tuberculosis.

  14. A Influência da Escola e da Mídia na Obtenção dos Conhecimentos Astronômicos

    NASA Astrophysics Data System (ADS)

    da Cunha, W. S.; Voelzke, M. R.; Amaral, L. H.

    2006-08-01

    O universo em que vivemos possui segredos jamais imaginados pelo homem, fruto da pequena proporção que ocupamos diante de um cosmos infinito. A astronomia funciona como um instrumento que sacia a sede humana em desvendar esses segredos, estudando as galáxias, quasares, pulsares além da existência de todos os elementos que preenchem o espaço cósmico, o vácuo, não mais vazio como se pensou em outros tempos. A mídia explora esse campo de forma mística e também científica. A difusão adequada e dentro dos padrões educacionais vigentes, de conceitos astronômicos, se faz necessária, devido sua presença nos conteúdos escolares, centros de ciência e na mídia, de modo geral. A reforma do Currículo Básico da Escola Pública da maioria dos Estados brasileiros introduziu conceitos astronômicos desde a pré-escola até o Ensino Médio. Num estudo realizado com 1.032 alunos do Ensino Médio de seis escolas estaduais, revelou-se através da aplicação de um questionário que abordava conheciment os básicos em astronomia, como estes foram adquiridos e qual era a infra-estrutura oferecida pela escola: para 66,2% dos entrevistados o professor já fez alguma apresentação a respeito de astronomia. O presente estudo revelou também que 44,5% dos alunos entrevistados adquiriram seus conhecimentos astronômicos na escola, 28,1% através da televisão e 27,4% afirmaram que seus conhecimentos foram obtidos através de outros tipos de mídia (internet, filmes e revistas). Embora o estudo revele claramente que há certo equilíbrio na forma em que os alunos obtiveram seus conhecimentos astronômicos, a mídia ainda explora e muitas vezes desperta o interesse pela astronomia com assuntos que não fazem parte de nosso cotidiano como, por exemplo, o homem na Lua, os projetos espaciais e a primeira viagem de um astronauta brasileiro no espaço. Porém, em certos casos, a mídia pode promover conhecimentos incompletos ou mesmo equivocados sobre os conceitos que envolvam

  15. Qual o Papel da Escola e da Mídia na Obtenção dos Conhecimentos Astronômicos?

    NASA Astrophysics Data System (ADS)

    da Cunha, W. S.; Voelzke, M. R.; Amaral, L. H.

    2007-08-01

    É amplamente reconhecido que as pessoas em geral têm grande fascínio e interesse pela Astronomia. Por outro lado, o conteúdo dessa área incluído no ensino formal está longe de ser abrangente e suficiente para suprir a demanda. Esse interesse permite aperfeiçoar a divulgação e o ensino não formal de Astronomia através da mídia aliando a adequação do conteúdo à expectativa das pessoas. A reforma do Currículo Básico da Escola Pública da maioria dos Estados brasileiros tem introduzido Astronomia desde a pré-escola até o Ensino Médio. Num estudo realizado com 1180 alunos do Ensino Médio de seis escolas estaduais, revelou-se através da aplicação de um formulário contendo questões que abordavam conhecimentos básicos em Astronomia, como foram adquiridos tais conhecimentos e à infra-estrutura da escola. Para 66,1% dos entrevistados o professor já fez alguma apresentação a respeito de Astronomia. O presente estudo revelou também que 54,4% dos alunos entrevistados adquiriram seus conhecimentos astronômicos na escola, 18,4% através da televisão e 27,1% afirmaram que seus conhecimentos foram obtidos através de outros tipos de mídia (internet, livros didáticos, filmes e revistas). Embora o estudo revele claramente que há certo equilíbrio no meio em que os alunos obtiveram seus conhecimentos astronômicos, a mídia busca não somente sua difusão, mas a disponibilização desse conhecimento de maneira correta, que às vezes, não é atingido, apresentando conceitos sem fundamentação e incorretos. Por outro lado, no dia-a-dia escolar, é comum encontrar professores que vêm para as aulas com concepções prévias, que podem diferir substancialmente das idéias a serem ensinadas, dificultando o aprendizado de futuros conceitos científicos. Uma avaliação criteriosa, avaliando as dificuldades dos professores em determinar o sentido correto dos conceitos e observando a metodologia que utilizam no ensino, poderá proporcionar uma melhor

  16. Multifunctional T Cell Response to DosR and Rpf Antigens Is Associated with Protection in Long-Term Mycobacterium tuberculosis-Infected Individuals in Colombia

    PubMed Central

    Arroyo, Leonar; Rojas, Mauricio; Franken, Kees L. M. C.; Ottenhoff, Tom H. M.

    2016-01-01

    Multifunctional T cells have been shown to be protective in chronic viral infections. In mycobacterial infections, however, evidence for a protective role of multifunctional T cells remains inconclusive. Short-term cultures of peripheral blood mononuclear cells stimulated with the Mycobacterium tuberculosis RD1 antigens 6-kDa early secretory antigenic target (ESAT6) and 10-kDa culture filtrate antigen (CFP10), which are induced in the early infection phase, have been mainly used to assess T cell multifunctionality, although long-term culture assays have been proposed to be more sensitive than short-term assays for assessment of memory T cells, which are essential for long-term immunity. Here we used a long-term culture assay system to study the T cell immune responses to the M. tuberculosis latency-associated DosR antigens and reactivation-associated Rpf antigens, compared to ESAT6 and CFP10, in patients with pulmonary tuberculosis (PTB) and household contacts of PTB patients with long-term latent tuberculosis infection (ltLTBI), in a community in which M. tuberculosis is endemic. Our results showed that the DosR antigens Rv1737c (narK2) and Rv2029c (pfkB) and the Rv2389c (rpfD) antigen of M. tuberculosis induced higher frequencies of CD4+ or CD8+ mono- or bifunctional (but not multifunctional) T cells producing interferon gamma (IFN-γ) and/or tumor necrosis alpha (TNF-α) in ltLTBI, compared to PTB. Moreover, the frequencies of CD4+ and/or CD8+ T cells with a CD45RO+ CD27+ phenotype were higher in ltLTBI than in PTB. Thus, the immune responses to selected DosR and Rpf antigens may be associated with long-term latency, correlating with protection from M. tuberculosis reactivation in ltLTBI. Further study of the functional and memory phenotypes may contribute to further discrimination between the different states of M. tuberculosis infections. PMID:27489136

  17. Geochemical and isotopic evidence for the petrogenesis and emplacement tectonics of the Serra dos Órgãos batholith in the Ribeira belt, Rio de Janeiro, Brazil

    NASA Astrophysics Data System (ADS)

    Machado, Rômulo; Philipp, Ruy Paulo; McReath, Ian; Peucat, Jean Jacques

    2016-07-01

    The Serra dos Órgãos batholith in the State of Rio de Janeiro (Brazil) is a NE-SW-trending elongated body that occupies ca. 5000 km2 in plan view. It is a foliated intrusion, especially at its borders and is crosscut by syn-magmatic shear zones, with foliations that are moderately-to steeply-dipping to the northwest and moderately-to shallow-dipping in the center and to the southeast, in a configuration of a large laccolith. It was emplaced between 560 and 570 Ma, during an extensional episode that was part of a series of events that comprise the Brasiliano Orogeny in SE Brazil, and which includes deformation, metamorphism and granite intrusion during the interval between 630 and 480 Ma. The two main rock types in the batholith are biotite-hornblende monzogranite, and biotite leucogranite, with subordinate tonalite, granodiorite, diorite, quartz diorite (enclaves), aplite and pegmatite. Harker-type diagrams help show two rock groups with similar trends of evolution: a dioritic and a granitic. The first one is tholeiitic, whereas the second is calc-alkaline, with medium-to high-K calc-alkaline affinity and metaluminous to slightly peraluminous character. In both groups strong decrease in Al2O3, MgO, FeOT and CaO relative to silica contents are observed, which is compatible with trends of fractional crystallization involving clinopyroxene and/or hornblende, plagioclase, opaque minerals, apatite, microcline and biotite. The Sr and Nd isotopic data suggest recycling of a Paleoproterozoic crust as an important petrological process to generate the batholith rocks. Geothermometry (amphibole composition) and geobarometry (saturation in zircon and apatite) indicate that most of the batholith solidified at mid to lower crustal levels at about 750 °C and between 5 and 5.5 kbar. We consider that Serra dos Órgãos crustal protoliths underwent melting caused by the interaction with hotter mafic magma at the base of the crust. These two magmas, with distinct initial

  18. Multifunctional T Cell Response to DosR and Rpf Antigens Is Associated with Protection in Long-Term Mycobacterium tuberculosis-Infected Individuals in Colombia.

    PubMed

    Arroyo, Leonar; Rojas, Mauricio; Franken, Kees L M C; Ottenhoff, Tom H M; Barrera, Luis F

    2016-10-01

    Multifunctional T cells have been shown to be protective in chronic viral infections. In mycobacterial infections, however, evidence for a protective role of multifunctional T cells remains inconclusive. Short-term cultures of peripheral blood mononuclear cells stimulated with the Mycobacterium tuberculosis RD1 antigens 6-kDa early secretory antigenic target (ESAT6) and 10-kDa culture filtrate antigen (CFP10), which are induced in the early infection phase, have been mainly used to assess T cell multifunctionality, although long-term culture assays have been proposed to be more sensitive than short-term assays for assessment of memory T cells, which are essential for long-term immunity. Here we used a long-term culture assay system to study the T cell immune responses to the M. tuberculosis latency-associated DosR antigens and reactivation-associated Rpf antigens, compared to ESAT6 and CFP10, in patients with pulmonary tuberculosis (PTB) and household contacts of PTB patients with long-term latent tuberculosis infection (ltLTBI), in a community in which M. tuberculosis is endemic. Our results showed that the DosR antigens Rv1737c (narK2) and Rv2029c (pfkB) and the Rv2389c (rpfD) antigen of M. tuberculosis induced higher frequencies of CD4(+) or CD8(+) mono- or bifunctional (but not multifunctional) T cells producing interferon gamma (IFN-γ) and/or tumor necrosis alpha (TNF-α) in ltLTBI, compared to PTB. Moreover, the frequencies of CD4(+) and/or CD8(+) T cells with a CD45RO(+) CD27(+) phenotype were higher in ltLTBI than in PTB. Thus, the immune responses to selected DosR and Rpf antigens may be associated with long-term latency, correlating with protection from M. tuberculosis reactivation in ltLTBI. Further study of the functional and memory phenotypes may contribute to further discrimination between the different states of M. tuberculosis infections.

  19. Geology and geochemistry of Pelagatos, Cerro del Agua, and Dos Cerros monogenetic volcanoes in the Sierra Chichinautzin Volcanic Field, south of México City

    NASA Astrophysics Data System (ADS)

    Agustín-Flores, Javier; Siebe, Claus; Guilbaud, Marie-Noëlle

    2011-04-01

    This study focuses on the geology and geochemistry of three closely-spaced monogenetic volcanoes that are located in the NE sector of the Sierra Chichinautzin Volcanic Field near México City. Pelagatos (3020 m.a.s.l.) is a small scoria cone (0.0017 km 3) with lava flows (0.036 km 3) that covered an area of 4.9 km 2. Cerro del Agua scoria cone (3480 m.a.s.l., 0.028 km 3) produced several lava flows (0.24 km 3) covering an area of 17.6 km 2. Dos Cerros is a lava shield which covers an area of 80.3 km 2 and is crowned by two scoria cones: Tezpomayo (3080 m.a.s.l., 0.022 km 3) and La Ninfa (3000 m.a.s.l., 0.032 km 3). The eruptions of Cerro del Agua and Pelagatos occurred between 2500 and 14,000 yr BP. The Dos Cerros eruption took place close to 14,000 yr BP as constrained by radiocarbon dating. Rocks from these three volcanoes are olivine-hypersthene normative basaltic andesites and andesites with porphyritic, aphanitic, and glomeroporphyritic textures. Their mineral assemblages include olivine, clinopyroxene, and orthopyroxene phenocrysts (≤ 10 vol.%) embedded in a trachytic groundmass which consists mainly of plagioclase microlites and glass. Pelagatos rocks also present quartz xenocrysts. Due to their high Cr and Ni contents, and high Mg#s, Pelagatos rocks are considered to be derived from primitive magmas, hence the importance of this volcano for understanding petrogenetic processes in this region. Major and trace element abundances and petrography of products from these volcanoes indicate a certain degree of crystal fractionation during ascent to the surface. However, the magmas that formed the volcanoes evolved independently from each other and are not cogenetically related. REE, HFSE, LILE, and isotopic (Sr, Nd, and Pb) compositions point towards a heterogeneous mantle source that has been metasomatized by aqueous/melt phases from the subducted Cocos slab. There is no clear evidence of important crustal contributions in the compositions of Pelagatos and

  20. [Fatty acid metabolism in patients with idiopathic dilated cardiomyopathy: characteristics and prognostic implications].

    PubMed

    Narita, M; Kurihara, T

    1995-05-01

    The characteristics of myocardial fatty acid metabolism in patients with idiopathic dilated cardiomyopathy (DCM) were investigated by myocardial imaging with beta-methyl-p-[123I]iodophenyl-pentadecanoic acid (BMIPP) in 16 patients with DCM, 8 patients with hypertensive heart failure (HHF), and 11 normal subjects. Rest myocardial imaging with BMIPP and 201Tl was performed on another day. The index of myocardial BMIPP uptake, or uptake ratio, was calculated from the percentage uptakes of BMIPP and 201Tl. The index of inhomogeneity of intramyocardial isotope distribution was calculated as the coefficient of variation of BMIPP and 201Tl. The uptake ratio was significantly lower in DCM and HHF patients than in normal subjects (p < 0.01). Uptake ratio correlated well with fractional shortening (r = 0.76, p < 0.01), and left ventricular ejection fraction (r = 0.58, p < 0.01). Although uptake ratio was not different between DCM and HHF patients, defects in BMIPP imaging appeared more frequently in DCM (69%) than in HHF (38%) patients. Furthermore, the extent of the defect in BMIPP imaging in DCM patients was larger than that in 201Tl imaging (p < 0.05), but in HHF patients the extent of the defects in both methods was similar. The coefficient of variation of BMIPP in DCM patients was greater than those in HHF patients and in normal subjects, but those of 201Tl were not different between the three groups. The coefficient of variation of BMIPP in DCM patients correlated well with serum norepinephrine level (r = 0.57, p < 0.01) and atrial natriuretic peptide (r = 0.77, p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Optimization of Acquisition Parameters for Simultaneous ,^^201rm Tl; and ,^^99rm mrm Tc Dual-Isotope Myocardial Imaging

    NASA Astrophysics Data System (ADS)

    Wang, Wen-Tung; Tsui, B. M. W.; Lalush, D. S.; Tocharoenchai, C.; Frey, E. C.

    2005-10-01

    In /sup 201/Tl//sup 99m/Tc dual-isotope simultaneous-acquisition (DISA) myocardial imaging, crosstalk due to Tc photons results in significant contamination of the Tl data. The objective of this work is to seek the acquisition parameters (i.e., energy window width and center) that have the optimal tradeoff between minimizing the crosstalk and maximizing the detection efficiency. The optimization criterion was based on maximizing an ideal observer signal-to-noise ratio (SNR) for the myocardial defect detection task using single-isotope and DISA projection images acquired from a torso phantom. For single-isotope images, the optimal energy windows (width/center: 26 keV/75 keV and 28 keV/165 keV for /sup 201/Tl, 30 keV/142 keV for /sup 99m/Tc) are wider than typical windows. For DISA imaging, the optimal windows varied with the /sup 99m/Tc to /sup 201/Tl activity ratio and are thus likely to depend on the uptake ratio in each patient. Using the optimal ratio 2.25-2.75 (148 MBq /sup 201/Tl and 333-407 MBq /sup 99m/Tc) with the corresponding optimal windows (22 keV/72 keV, 24 keV/167 keV, and 24 keV/140 keV) gives /sup 201/Tl images with substantially increased SNRs as well as /sup 99m/Tc images with SNRs same as those of 370 MBq /sup 99m/Tc-only images. However, without the addition of crosstalk compensation, the use of the optimal activity and energy windows alone is likely not sufficient to restore the DISA Tl SNR to that of Tl-only image.

  2. Correlation of left ventricular dyssynchrony with myocardial stunning using dual single photon emission computed tomography of (123)iodine-beta-methyl iodophenyl pentadecanoic acid and (201)thallium scintigraphy after reperfusion therapy.

    PubMed

    Maruyama, Yoshiaki; Masaki, Nobuyuki; Shimizu, Yuji; Honda, Norinari; Yoshimoto, Nobuo

    2009-11-01

    Left ventricular (LV) dyssynchrony after reperfusion therapy has been closely examined as a cause of chronic remodeling, but the details have not been clarified. The present study measured LV dyssynchrony appearing immediately after reperfusion therapy using real-time three-dimensional echocardiography (RT-3DE), and assessed the significance of this phenomenon in relation to dual single photon emission computed tomography (SPECT) of (123)iodine beta methyliodophenyl pentadecanoic acid ((123)I-BMIPP) and (201)thallium ((201)Tl). Subjects comprised 58 patients with first-time acute myocardial infarction who received reperfusion therapy and underwent RT-3DE and dual SPECT of (123)I-BMIPP and (201)Tl within two weeks of onset. Two dyssynchrony parameters were measured using RT-3DE in the acute phase and six months later. After evaluating the correlation of these dyssynchrony parameters to resting (201)Tl uptake, (201)Tl washout, (123)I-BMIPP uptake, and (201)Tl-(123)I-BMIPP discrepancy (Tl-BMIPP discrepancy), we compared scintigraphic parameters in the chronic phase between groups with improved dyssynchrony and those without. Acute dyssynchrony exhibited a significant positive correlation to Tl-BMIPP discrepancy and it was significantly increased in the group with improved dyssynchrony in the chronic phase, revealing close relationship between dyssynchrony and Tl-BMIPP discrepancy. Then the subjects were divided into positive Tl-BMIPP discrepancy and negative discrepancy groups, and the parameters of cardiac function were compared between them. In the chronic phase, improved cardiac function was observed in the group with positive Tl-BMIPP discrepancy compared to negative discrepancy. LV dyssynchrony after reperfusion therapy correlates positively with Tl-BMIPP discrepancy, reflecting acute myocardial stunning, in which ventricular contraction improves during the chronic phase.

  3. Multimodality imaging approach for serial assessment of regional changes in lower extremity arteriogenesis and tissue perfusion in a porcine model of peripheral arterial disease.

    PubMed

    Stacy, Mitchel R; Yu, Da Yu; Maxfield, Mark W; Jaba, Irina M; Jozwik, Bartosz P; Zhuang, Zhen W; Lin, Ben A; Hawley, Christi L; Caracciolo, Christopher M; Pal, Prasanta; Tirziu, Daniela; Sampath, Smita; Sinusas, Albert J

    2014-01-01

    A standard quantitative imaging approach to evaluate peripheral arterial disease does not exist. Quantitative tools for evaluating arteriogenesis in vivo are not readily available, and the feasibility of monitoring serial regional changes in lower extremity perfusion has not been examined. Serial changes in lower extremity arteriogenesis and muscle perfusion were evaluated after femoral artery occlusion in a porcine model using single photon emission tomography (SPECT)/CT imaging with postmortem validation of in vivo findings using gamma counting, postmortem imaging, and histological analysis. Hybrid 201Tl SPECT/CT imaging was performed in pigs (n=8) at baseline, immediately postocclusion, and at 1 and 4 weeks postocclusion. CT imaging was used to identify muscle regions of interest in the ischemic and nonischemic hindlimbs for quantification of regional changes in CT-defined arteriogenesis and quantification of 201Tl perfusion. Four weeks postocclusion, postmortem tissue 201Tl activity was measured by gamma counting, and immunohistochemistry was performed to assess capillary density. Relative 201Tl retention (ischemic/nonischemic) was reduced immediately postocclusion in distal and proximal muscles and remained lower in calf and gluteus muscles 4 weeks later. Analysis of CT angiography revealed collateralization at 4 weeks within proximal muscles (P<0.05). SPECT perfusion correlated with tissue gamma counting at 4 weeks (P=0.01). Increased capillary density was seen within the ischemic calf at 4 weeks (P=0.004). 201Tl SPECT/CT imaging permits serial, regional quantification of arteriogenesis and resting tissue perfusion after limb ischemia. This approach may be effective for detection of disease and monitoring therapy in peripheral arterial disease.

  4. Clinical assessment of myocardial viability using MRI during a constant infusion of Gd-DTPA.

    PubMed

    Pereira, R S; Wisenberg, G; Prato, F S; Yvorchuk, K

    2000-12-01

    This study assessed the accuracy and feasibility of magnetic resonance imaging (MRI) during a constant infusion of gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) for the determination of myocardial viability in patients with recent acute myocardial infarction (AMI). Nine patients were studied within 10 days of AMI. Rest-redistribution 201Thallium (201Tl) single photon emission computed tomography (SPECT) was used as a gold standard for viability. Using MRI, regional perfusion was assessed using dynamic imaging during a bolus injection of Gd-DTPA and viability was assessed during a continuous infusion. Finally, cine MR images were acquired at baseline, during low-dose dobutamine infusion and after recovery. To assess viability, the left ventricle was divided into 16 segments and signal intensity in corresponding MRI and redistribution SPECT segments were compared. Wall thickening index (WTI) was determined at each step during the dobutamine study. The results revealed that in five patients, reduced perfusion in infarcted regions was observed qualitatively during dynamic first pass imaging. There was a significant inverse correlation between 201Tl uptake and MRI signal intensity, i.e. infarcted tissue (low 201Tl uptake) had increased MR signal intensity. Segments were separated into normal (201Tl uptake > 90%) and infarcted (< 601%). lnfarcted MRI segments had greater signal intensity than normal segments (179 +/- 50 vs. 102 +/- 14%; P < 0.0001). WTI in normal segments increased by 18 +/- 8.5% (P < 0.0001) from baseline to 10 microg/kg per min of dobutamine while infarcted tissue WTI decreased 2.8 +/- 7.2% (P = 0.17). Thus regions of myocardium that were infarcted as defined by reduced 201Tl uptake and absent contractile reserve showed greatly increased MRI signal intensity during a constant infusion of Gd-DTPA. The use of MRI during a constant infusion of Gd-DTPA is accurate and feasible for the determination of myocardial necrosis in a clinical setting.

  5. Osteobiographic analysis of skeleton I, Sítio Toca dos Coqueiros, Serra da Capivara National Park, Brazil, 11,060 BP: first results.

    PubMed

    Lessa, Andrea; Guidon, Niéde

    2002-06-01

    This paper presents an osteobiographic analysis of a single skeleton found in a small rock shelter known as Toca dos Coqueiros, Piauí, Brazil. This find is of interest because of an exceptionally old radiocarbon date associated with it. The date (11,060 BP) was obtained from charcoal associated directly with the skeleton. This is an interesting find because of the rarity of osteobiographic studies of skeletons of such antiquity. Despite the existence of two projectile points in association with the burial, the morphological and molecular analyses of the skeleton demonstrated that this was a female. She was about 35-45 years of age at death. The skeleton exhibited acute and chronic bone lesions. Oral pathology was also observed, including an interproximal dental groove, probably caused by the therapeutic use of a cactus thorn. This could be one of the oldest cases of an analgesic plant used in the prehistoric Americas.

  6. Occurrence of Aglae caerulea Lepeletier & Serville (Hymenoptera: Apidae: Euglossini) in the Parque Nacional da Chapada dos Guimarães, Mato Grosso State, Brazil.

    PubMed

    dos Anjos-Silva, Evandson J; Camillo, Evandro; Garófalo, Carlos A

    2006-01-01

    In a study conducted in the gallery forest of the Vale doVeu de Noiva in the Parque Nacional da Chapada dos Guimarães, Mato Grosso state, chemical baits were used to attract and sample male orchid bees. From September 2003 to July 2005, male euglossine bees were captured monthly, from 8:00 a.m. to 4:00 p.m. as they arrived at the baits. Of the 264 males captured, eight males belonged to Aglae caerulea Lepeletier & Serville, a cleptoparasitic euglossine species that presumably occurred only in the Amazon basin. Therefore, the occurrence of A. caerulea in this study area extends its geographical distribution range by approximately 2,400 km southwards in South America, as it is now recorded in both the Amazon and Platina basins.

  7. Feeding ecology of the lizard Tropidurus oreadicus Rodrigues 1987 (Tropiduridae) at Serra dos Carajás, Pará state, northern Brazil.

    PubMed

    Rocha, C F D; Siqueira, C C

    2008-02-01

    Tropidurus species commonly prey on arthropods, but they may also feed on vertebrates and plant material. The lizard Tropidurus oreadicus (Tropiduridae) is common in open vegetation habitats and generally has sexual dimorphism. In this study we analyzed the diet of T. oreadicus at Serra dos Carajás, Pará, in the north of Brazil. Snout-vent length (SVL) and jaw width (JW) were taken for 34 lizards. There was a significant difference in SVL and in JW, with males being larger than females. All lizards analyzed contained food in their stomachs. The diet of T. oreadicus at Serra dos Carajás was characterized by the consumption of a relative wide spectrum of food item categories (21 types of items), consisting of arthropods, part of one vertebrate and plant material, which characterizes the diet of a generalist predator. Volumetrically, the most important items in the diet of both sexes of T. oreadicus were flowers (M = 61.7%; F = 33%) and orthopterans (M = 1.7%; F = 3.5%). Ants were the most frequently consumed (100% for both sexes) and the most numerous (M = 94.5%; F = 89.4%) food item. Flowers also were frequently consumed (M = 91.7%; F = 54.5%), with their relative consumption differing significantly between sexes. There was not a significant sexual difference in prey volume, neither in number of preys per stomach, nor in type of prey ingested. There was no relationship between lizard jaw width and the mean volume of prey. The data showed that T. oreadicus is a relatively generalist lizard in terms of diet and that consumes large volumes of plant material, especially flowers of one species of genus Cassia.

  8. Geochemistry of upland lacustrine sediments from Serra dos Carajás, Southeastern Amazon, Brazil: Implications for catchment weathering, provenance, and sedimentary processes

    NASA Astrophysics Data System (ADS)

    Sahoo, Prafulla Kumar; Felix Guimarães, José Tasso; Martins Souza-Filho, Pedro Walfir; Sousa da Silva, Marcio; Maurity, Clovis Wagner; Powell, Mike A.; Rodrigues, Tarcísio Magevski; Fonseca da Silva, Delmo; Mardegan, Sílvia Fernanda; Furtini Neto, Antonio Eduardo; Dall'Agnol, Roberto

    2016-12-01

    A multi-proxy geochemical study of surficial sediments of an upland lake (Amendoim Lake), located in the Serra dos Carajás region, Brazil, was carried out to understand catchment weathering and provenance of sediments in the basin, as well as sedimentary processes. The carbon and nitrogen isotopic compositions of organic matter in the sediment were quite homogeneous, and suggest that the organic sources for this lake are mainly composed of palms and submerged macrophytes. The R-mode factor analysis indicates that most of the trace elements, including rare earth elements (REEs), are clustered with Al (Group 1), Si is grouped with Zr and Hf (Group 4), total organic carbon (TOC) with TS and Hg (Group 2), and Fe with Mn and As (Group 3). The elements of the Group 1 show strong positive correlations with Al, suggesting that these elements are hosted in detrital minerals during laterization in the catchment basin and not significantly affected by diagenesis. The high CIA values (96-99) of sediments together with their position in A-CN-K and log (Fe2O3/K2O) vs log (SiO2/Al2O3) plots indicate intense chemical weathering in source area. However, similar geochemical signatures between lake sediments and catchment lateritic crust indicates that mechanical erosion was the dominant sediment formation process. REE patterns normalized to chondrite along with geochemical indices (Al/K, Al/Ti, La/Th, La/Al, Ti/Zr, Zr/Hf, Th/Sc, Co/Th, Ba/Sr, and Eu/Eu*) also indicate that the sediments are mainly derived from laterite crust. This study provides reliable background information to reconstruct weathering processes and lake evolution in the Serra dos Carajás area.

  9. Diet of Ameerega braccata (Steindachner, 1864) (Anura: Dendrobatidae) from Chapada dos Guimarães and Cuiabá, Mato Grosso State, Brazil.

    PubMed

    Forti, L R; Tissiani, A S O; Mott, T; Strüssmann, C

    2011-02-01

    The understanding of feeding habits is important for anurans in general, both from an ecological and a phylogenetic perspective. For diurnal poison frogs belonging to the Dendrobatidae family, diet aspects play a crucial role in their defense and survival. Herein, we investigated feeding habits, foraging behaviour, and overall effects of habitat, sex, and body size on the diet of individuals of Ameerega braccata, a poorly known dendrobatid species. Specimens were observed and collected in the type-locality, Chapada dos Guimarães, and in the neighbouring municipality of Cuiabá, both in the State of Mato Grosso, Midwestern Brazil. The most important prey categories for A. braccata were Formicidae, Isoptera, and Acari, whose representatives were caught during active foraging. Individuals from Chapada dos Guimarães population consumed more Acari but fewer Isoptera than individuals from Cuiabá. Despite this, niche breadth values were narrow and similar for the two populations. Individuals from two distinct habitats (campo sujo and cerrado stricto sensu) showed differences in their diet, probably as an effect of differential prey availability. Females consumed more Isoptera than males. The number of prey categories used as food was not influenced by the variation of body size of the target species. However, the abundance and the volume of consumed Acari were statistically correlated with body size. The main results suggest that Ameerega braccata has a narrow niche breadth, as well as a specialised diet in ants, termites, and mites, which reinforces the hypotheses of close association between Acari consumption and the presence of skin toxic alkaloids, already found in other species of Dendrobatidae. Although differences in prey consumption between sexes are uncommon among poisonous frogs, differences in the diet composition between age classes, which probably reduce intraspecific competition, are frequently reported.

  10. Novel vaccine potential of Rv3131, a DosR regulon-encoded putative nitroreductase, against hyper-virulent Mycobacterium tuberculosis strain K.

    PubMed

    Kwon, Kee Woong; Kim, Woo Sik; Kim, Hongmin; Han, Seung Jung; Hahn, Mi-Young; Lee, Jong Seok; Nam, Ki Taek; Cho, Sang-Nae; Shin, Sung Jae

    2017-03-08

    Accumulating evidence indicates that latency-associated Mycobacterium tuberculosis (Mtb)-specific antigens from the dormancy survival regulator regulon (DosR) may be promising novel vaccine target antigens for the development of an improved tuberculosis vaccine. After transcriptional profiling of DosR-related genes in the hyper-virulent Beijing Mtb strain K and the reference Mtb strain H37Rv, we selected Rv3131, a hypothetical nitroreductase, as a vaccine antigen and evaluated its vaccine efficacy against Mtb K. Mtb K exhibited stable and constitutive up-regulation of rv3131 relative to Mtb H37Rv under three different growth conditions (at least 2-fold induction) including exponential growth in normal culture conditions, hypoxia, and inside macrophages. Mice immunised with Rv3131 formulated in GLA-SE, a well-defined TLR4 adjuvant, displayed enhanced Rv3131-specific IFN-γ and serum IgG2c responses along with effector/memory T cell expansion and remarkable generation of Rv3131-specific multifunctional CD4(+) T cells co-producing TNF-α, IFN-γ and IL-2 in both spleen and lung. Following challenge with Mtb K, the Rv3131/GLA-SE-immunised group exhibited a significant reduction in bacterial number and less extensive lung inflammation accompanied by the obvious persistence of Rv3131-specific multifunctional CD4(+) T cells. These results suggest that Rv3131 could be an excellent candidate for potential use in a multi-antigenic Mtb subunit vaccine, especially against Mtb Beijing strains.

  11. Novel vaccine potential of Rv3131, a DosR regulon-encoded putative nitroreductase, against hyper-virulent Mycobacterium tuberculosis strain K

    PubMed Central

    Kwon, Kee Woong; Kim, Woo Sik; Kim, Hongmin; Han, Seung Jung; Hahn, Mi-Young; Lee, Jong Seok; Nam, Ki Taek; Cho, Sang-Nae; Shin, Sung Jae

    2017-01-01

    Accumulating evidence indicates that latency-associated Mycobacterium tuberculosis (Mtb)-specific antigens from the dormancy survival regulator regulon (DosR) may be promising novel vaccine target antigens for the development of an improved tuberculosis vaccine. After transcriptional profiling of DosR-related genes in the hyper-virulent Beijing Mtb strain K and the reference Mtb strain H37Rv, we selected Rv3131, a hypothetical nitroreductase, as a vaccine antigen and evaluated its vaccine efficacy against Mtb K. Mtb K exhibited stable and constitutive up-regulation of rv3131 relative to Mtb H37Rv under three different growth conditions (at least 2-fold induction) including exponential growth in normal culture conditions, hypoxia, and inside macrophages. Mice immunised with Rv3131 formulated in GLA-SE, a well-defined TLR4 adjuvant, displayed enhanced Rv3131-specific IFN-γ and serum IgG2c responses along with effector/memory T cell expansion and remarkable generation of Rv3131-specific multifunctional CD4+ T cells co-producing TNF-α, IFN-γ and IL-2 in both spleen and lung. Following challenge with Mtb K, the Rv3131/GLA-SE-immunised group exhibited a significant reduction in bacterial number and less extensive lung inflammation accompanied by the obvious persistence of Rv3131-specific multifunctional CD4+ T cells. These results suggest that Rv3131 could be an excellent candidate for potential use in a multi-antigenic Mtb subunit vaccine, especially against Mtb Beijing strains. PMID:28272457

  12. Conversion of a heme-based oxygen sensor to a heme oxygenase by hydrogen sulfide: effects of mutations in the heme distal side of a heme-based oxygen sensor phosphodiesterase (Ec DOS).

    PubMed

    Du, Yongming; Liu, Gefei; Yan, Yinxia; Huang, Dongyang; Luo, Wenhong; Martinkova, Marketa; Man, Petr; Shimizu, Toru

    2013-10-01

    The heme-based oxygen-sensor phosphodiesterase from Escherichia coli (Ec DOS), is composed of an N-terminal heme-bound oxygen sensing domain and a C-terminal catalytic domain. Oxygen (O2) binding to the heme Fe(II) complex in Ec DOS substantially enhances catalysis. Addition of hydrogen sulfide (H2S) to the heme Fe(III) complex in Ec DOS also remarkably stimulates catalysis in part due to the heme Fe(III)-SH and heme Fe(II)-O2 complexes formed by H2S. In this study, we examined the roles of the heme distal amino acids, M95 (the axial ligand of the heme Fe(II) complex) and R97 (the O2 binding site in the heme Fe(II)-O2 complex) of the isolated heme-binding domain of Ec DOS (Ec DOS-PAS) in the binding of H2S under aerobic conditions. Interestingly, R97A and R97I mutant proteins formed an oxygen-incorporated modified heme, verdoheme, following addition of H2S combined with H2O2 generated by the reactions. Time-dependent mass spectroscopic data corroborated the findings. In contrast, H2S did not interact with the heme Fe(III) complex of M95H and R97E mutants. Thus, M95 and/or R97 on the heme distal side in Ec DOS-PAS significantly contribute to the interaction of H2S with the Fe(III) heme complex and also to the modification of the heme Fe(III) complex with reactive oxygen species. Importantly, mutations of the O2 binding site of the heme protein converted its function from oxygen sensor to that of a heme oxygenase. This study establishes the novel role of H2S in modifying the heme iron complex to form verdoheme with the aid of reactive oxygen species.

  13. Humoral Responses to Rv1733c, Rv0081, Rv1735c, and Rv1737c DosR Regulon-Encoded Proteins of Mycobacterium tuberculosis in Individuals with Latent Tuberculosis Infection

    PubMed Central

    Nalwoga, Angela; Levin, Jonathan; Ottenhoff, Tom H. M.; Elliott, Alison M.; Cose, Stephen; Andia-Biraro, Irene

    2017-01-01

    Latent tuberculosis infection (LTBI) is evidence of immunological control of tuberculosis. Dormancy survival regulator (DosR) regulon-encoded proteins may have a role in the maintenance of LTBI. T cell responses to Rv1733c, Rv0081, Rv1735c, and Rv1737c DosR regulon-encoded proteins were found to be most frequent among household contacts of TB cases from Uganda compared to other DosR proteins, but antibody responses were not described. We characterized antibody responses to these proteins in individuals from Uganda. Antibodies to Rv1733c, Rv0081, Rv1735c, and Rv1737c DosR regulon-encoded proteins were measured in 68 uninfected individuals, 62 with LTBI, and 107 with active pulmonary tuberculosis (APTB) cases. There were no differences in the concentrations of antibodies to Rv0081, Rv1735c, and Rv1737c DosR regulon-encoded proteins between individuals with LTBI and APTB and those who were uninfected. LTBI was associated with higher concentrations of antibodies to Rv1733c in female participants [adjusted geometric mean ratio: 1.812, 95% confidence interval (CI): 1.105 2.973, and p = 0.019] but not in males (p value for interaction = 0.060). Antibodies to the four DosR regulon-encoded proteins investigated may not serve as good biomarkers of LTBI in the general population. More of the M.tb proteome needs to be screened to identify proteins that induce strong antibody responses in LTBI. PMID:28255560

  14. A estabilidade dos PAHS em função da energia da radiação interestelar nas faixas UV e raios-X

    NASA Astrophysics Data System (ADS)

    Pinotti, R.; Costa, R. K.; Boechat-Roberty, H. M.; Lago, A.; Souza, G. B.

    2003-08-01

    A nebulosa CRL 618, uma proto-nebulosa planetária cuja nuvem molecular espessa envolve uma estrela B0, contém uma grande quantidade de C2H2 e CH4. Estas moléculas são consideradas os tijolos da criação de grandes moléculas carbonadas como os Hidrocarbonetos Policíclicos Aromáticos (PAHs). Esta nebulosa, por estar exposta a intensos campos de UV e Raios-X, é uma região de fotodissociação molecular que propicia a formação de novas moléculas, confirmada pela presença de C4H2 e C6H6 (Benzeno), que é a unidade básica dos PAHs. Atribui-se a esta família de moléculas orgânicas duas propriedades fundamentais, a resistência para sobreviver ao campo de radiação UV interestelar e a geração das bandas de emissão não identificadas (UIR) observadas no infravermelho. No entanto, alguns autores questionam a resistência dos PAHs ao campo de radiação UV interestelar. Empregando a técnica de Espectrometria de Massas por Tempo de Vôo, no modo de coincidência fotoelétron-fotoíon, estudamos a ionização e fragmentação das seguintes moléculas: Benzeno, Benzeno deuterado, Naftaleno, Antraceno e Fenantreno. Utilizamos uma fonte de Hélio monocromática em 21,21 eV (584,5 Å) e a radiação Síncroton do Laboratório Nacional de Luz Síncroton (LNLS) em diferentes energias nas proximidades da borda do C 1s ( 290 eV). Comprovamos a estabilidade dos PAHs sob ação de UV (21,21 eV), onde eles apresentam um baixo nível de fotodissociação, produzindo fragmentos ionizados com rendimento total na ordem de 5 por cento em relação ao íon molecular pai. Entretanto, em altas energias, na faixa de Raios-X, a quebra destas moléculas torna-se mais intensa, com a produção de muitos fragmentos. Como uma das rotas de fragmentação do Naftaleno é [(C10H8) = > (C6H6+) + (C4H2) + (e-)], e como temos as evidências observacionais da existência do C4H2 e C6H6 na nebulosa CRL 618, sugerimos que este ambiente também possui o Naftaleno.

  15. Mycobacterium tuberculosis DevR/DosR Dormancy Regulator Activation Mechanism: Dispensability of Phosphorylation, Cooperativity and Essentiality of α10 Helix

    PubMed Central

    Sharma, Saurabh; Tyagi, Jaya Sivaswami

    2016-01-01

    DevR/DosR is a well-characterized regulator in Mycobacterium tuberculosis which is implicated in various processes ranging from dormancy/persistence to drug tolerance. DevR induces the expression of an ~48-gene dormancy regulon in response to gaseous stresses, including hypoxia. Strains of the Beijing lineage constitutively express this regulon, which may confer upon them a significant advantage, since they would be ‘pre-adapted’ to the environmental stresses that predominate during infection. Aerobic DevR regulon expression in laboratory-manipulated overexpression strains is also reported. In both instances, the need for an inducing signal is bypassed. While a phosphorylation-mediated conformational change in DevR was proposed as the activation mechanism under hypoxia, the mechanism underlying constitutive expression is not understood. Because DevR is implicated in bacterial dormancy/persistence and is a promising drug target, it is relevant to resolve the mechanistic puzzle of hypoxic activation on one hand and constitutive expression under ‘non-inducing’ conditions on the other. Here, an overexpression strategy was employed to elucidate the DevR activation mechanism. Using a panel of kinase and transcription factor mutants, we establish that DevR, upon overexpression, circumvents DevS/DosT sensor kinase-mediated or small molecule phosphodonor-dependent activation, and also cooperativity-mediated effects, which are key aspects of hypoxic activation mechanism. However, overexpression failed to rescue the defect of C-terminal-truncated DevR lacking the α10 helix, establishing the α10 helix as an indispensable component of DevR activation mechanism. We propose that aerobic overexpression of DevR likely increases the concentration of α10 helix-mediated active dimer species to above the threshold level, as during hypoxia, and enables regulon expression. This advance in the understanding of DevR activation mechanism clarifies a long standing question as to

  16. Mycobacterium tuberculosis DevR/DosR Dormancy Regulator Activation Mechanism: Dispensability of Phosphorylation, Cooperativity and Essentiality of α10 Helix.

    PubMed

    Sharma, Saurabh; Tyagi, Jaya Sivaswami

    2016-01-01

    DevR/DosR is a well-characterized regulator in Mycobacterium tuberculosis which is implicated in various processes ranging from dormancy/persistence to drug tolerance. DevR induces the expression of an ~48-gene dormancy regulon in response to gaseous stresses, including hypoxia. Strains of the Beijing lineage constitutively express this regulon, which may confer upon them a significant advantage, since they would be 'pre-adapted' to the environmental stresses that predominate during infection. Aerobic DevR regulon expression in laboratory-manipulated overexpression strains is also reported. In both instances, the need for an inducing signal is bypassed. While a phosphorylation-mediated conformational change in DevR was proposed as the activation mechanism under hypoxia, the mechanism underlying constitutive expression is not understood. Because DevR is implicated in bacterial dormancy/persistence and is a promising drug target, it is relevant to resolve the mechanistic puzzle of hypoxic activation on one hand and constitutive expression under 'non-inducing' conditions on the other. Here, an overexpression strategy was employed to elucidate the DevR activation mechanism. Using a panel of kinase and transcription factor mutants, we establish that DevR, upon overexpression, circumvents DevS/DosT sensor kinase-mediated or small molecule phosphodonor-dependent activation, and also cooperativity-mediated effects, which are key aspects of hypoxic activation mechanism. However, overexpression failed to rescue the defect of C-terminal-truncated DevR lacking the α10 helix, establishing the α10 helix as an indispensable component of DevR activation mechanism. We propose that aerobic overexpression of DevR likely increases the concentration of α10 helix-mediated active dimer species to above the threshold level, as during hypoxia, and enables regulon expression. This advance in the understanding of DevR activation mechanism clarifies a long standing question as to the

  17. Novas determinações dos parâmetros atmosféricos das estrelas anãs brancas DA

    NASA Astrophysics Data System (ADS)

    Giovannini, O.; Costa, A. F. M.; Kepler, S. O.

    2003-08-01

    Nós temos selecionado uma amostra de estrelas anãs brancas DA (atmosfera de hidrogênio) a partir dos índices de Strömgren cujos valores estão próximos a região de instabilidade das estrelas anãs brancas DA variáveis, as chamadas estrelas DAV ou ZZ Ceti. O objetivo é determinar os parâmetros fundamentais (temperatura efetiva, Teff, aceleração da gravidade, log g, e massa) destas estrelas para verificar quais os parâmetros estelares estão envolvidos com o mecanismo de pulsação das estrelas DAV. Nós obtemos, até agora, mais de 120 espectros óticos de estrelas DA. Entre as estrelas selecionadas há 20 estrelas variáveis (DAV). Assim, podemos verificar se existem ou não estrelas não variáveis dentro da faixa de instabilidade das estrelas ZZ Ceti. Neste trabalho nós apresentamos a determinação dos parâmetros atmosféricos (temperatura efetiva, Teff, e aceleração da gravidade, log g) das estrelas anãs brancas DA usando os novos modelos de atmosfera ML2/a = 0.6. Estes modelos têm sido utilizados recentemente por fornecerem uma excelente consistência interna na determinação das temperaturas nas regiões do ultra-violeta e ótico. Os parâmetros atmosféricos são determinados espectroscopicamente através da comparação do fluxo de energia das linhas de Balmer (Hb à H9) entre os espectros observados e sintéticos (gerados pelos modelos de atmosfera). As temperaturas obtidas com os novos modelos são, em geral, menores (~ 1000 K menos) que as temperaturas determinadas anteriormente, com modelos ML1. Os valores de log g não mudaram significativamente (menos de 10%). A faixa de instabilidade das DAVs está entre 11000 e 13000 K, consistente com dados de outros autores.

  18. [Unified National Health System costs in São José dos Campos, São Paulo State, Brazil, for hospital admissions due to external causes].

    PubMed

    Melione, Luís Paulo Rodrigues; Mello-Jorge, Maria Helena Prado de

    2008-08-01

    The objective of this study was to identify direct expenditures for hospitalizations due to external causes in the Unified National Health System (SUS) in the city of São José dos Campos, São Paulo State, Brazil. Admissions to the Dr. José de Carvalho Florence Municipal Hospital resulting from external causes or injuries - ICD-10, chapters XIX and XX respectively - were analyzed for the first semester of 2003. 976 patient admission forms were analyzed, after data evaluation. Admissions with the highest total cost were those resulting from motor vehicle accidents and falls. The highest mean cost for hospitalization for injury was due to motor vehicle accidents (BRL 614.63), followed by assault (BRL 594.90). The highest mean cost for hospitalization due to injury was for cervical fractures (BRL 1,191.42) and head injuries (BRL 1,000.44). Hospitalizations with the highest daily cost were skull and facial fractures (BRL 166.72) and abdominal trauma (BRL 148.26). The study confirmed that motor vehicle accidents, falls, and assault are an important source of costs due to hospitalization for injuries.

  19. Analysis of the Astronomical Concepts Presented by Teachers of Science, Physics, and Mathematics of São José dos Campos / SP Municipality

    NASA Astrophysics Data System (ADS)

    Pereira Gonzaga, Edson; Voelzke, Marcos Rincon

    2013-11-01

    The aim of this work is to conduct a survey of alternative conceptions about the basic concepts of Astronomy from schoolteachers in the City of São José dos Campos. This study covers the the state-run education system and complies with legal documents related to the curriculum of educational systems, such as the Curriculum of São Paulo State and the Parameters of the National Curriculum (PCN). Alternative conceptions, mentioned in Langhi (2009) as very important, were used, because it is believed that if a student can learn these concepts before the methodological intervention, it is possible to prepare contextualized presentations for teachers, and consequently students, to compare what they already know with the new information they obtain in the sessions at the digital mobile planetarium (DMP) of the Universidade Cruzeiro do Sul. Afterwards, they may discuss in a forum, in the form of debate, seeking to draw conclusions relevant to the topic, and transmitting the same to students in Basic Education (EB). This is a case study with a quantitative survey and a qualitative analysis of data on astronomical concepts collected through two questionnaires, one before and one after the intervention, respecting the implementation period of the study,- here called methodological intervention of content presentations at the mobile planetarium - and on respective discussions.

  20. Implementing a Knowledge Translation Intervention in Long-Term Care: Feasibility Results From the Vitamin D and Osteoporosis Study (ViDOS)

    PubMed Central

    Kennedy, Courtney C.; Thabane, Lehana; Ioannidis, George; Adachi, Jonathan D.; Papaioannou, Alexandra

    2016-01-01

    Objectives To evaluate the feasibility of implementing an interdisciplinary, multifaceted knowledge translation intervention within long-term care (LTC) and to identify any challenges that should be considered in designing future studies. Design Cluster randomized controlled trial. Setting Forty LTC homes across the province of Ontario, Canada. Participants LTC teams composed of physicians, nurses, pharmacists, and other staff. Measurements Cluster-level feasibility measures, including recruitment, retention, data completion, and participation in the intervention. A process evaluation was completed by directors of care indicating which process/policy changes had been implemented. Results Recruitment and retention rates were 22% and 63%, respectively. Good fidelity with the intervention was achieved, including attendance at educational meetings. After ViDOS, 7 process indicators were being newly implemented by more than 50% of active intervention homes. Conclusion Despite recruitment and retention challenges, the multifaceted intervention produced a number of policy/process changes and had good intervention fidelity. This study is registered at ClinicalTrials.gov NCT01398527. PMID:24953541

  1. ASPECTS OF THE ECOLOGY OF PHLEBOTOMINES (Diptera: Psychodidae: Phlebotominae) IN AN AREA OF CUTANEOUS LEISHMANIASIS OCCURRENCE, MUNICIPALITY OF ANGRA DOS REIS, COAST OF RIO DE JANEIRO STATE, BRAZIL

    PubMed Central

    de Aguiar, Gustavo Marins; de Azevedo, Alfredo Carlos Rodrigues; de Medeiros, Wagner Muniz; Alves, João Ricardo Carreira; Rendeiro, Vanessa

    2014-01-01

    Over a complete two-year period, phlebotomine specimens were caught in an area of cutaneous leishmaniasis occurrence in the municipality of Angra dos Reis. A manual suction tube was used to catch phlebotomines on house walls, and also light traps in domestic and peridomestic settings and in the forest. This yielded 14,170 specimens of 13 species: two in the genus Brumptomyia and eleven in the genus Lutzomyia. L. intermedia predominantly in domestic and peridomestic settings, with little presence in the forest, with the same trend being found in relation to L. migonei, thus proving that these species have adapted to the human environment. L. fischeri appeared to be eclectic regarding location, but was seen to be proportionally more endophilic. L. intermedia and L. migonei were more numerous in peridomestic settings, throughout the year, while L. fischeri was more numerous in domestic settings except in March, April, May and September. From the prevalence of L. intermedia, its proven anthropophily and findings of this species naturally infected with Leishmania (Viannia) braziliensis, it can be incriminated as the main vector for this agent of cutaneous leishmaniasis in the study area, especially in the peridomestic environment. L. fischeri may be a coadjuvant in carrying the parasite. PMID:24626417

  2. Combined use of aerogammaspectrometry and geochemistry to access sediment sources in a shallow coral site at Armação dos Búzios, Brazil

    NASA Astrophysics Data System (ADS)

    Godiva, Danielly; Evangelista, Heitor; Kampel, Milton; Licinio, Marcus Vinicius; Munita, Casimiro

    2010-05-01

    Coral and reef environments in shallow waters are negatively affected by human activities in several coastal areas worldwide. It has been demonstrated that sediment influx and macronutrient discharges induce decline of coral population structure and diversity. Therefore, efforts to quantify sediment flux, sources and the biological response to sedimentation were conducted by several marine researchers. Herein, we investigated the case study of Armação dos Búzios/Brazil/Western South Atlantic, where coral colonies (mostly Siderastrea stellata) are under stress due to sediment apportionment as a consequence of regional human occupation. Classification of potential sediment source regions was based on a high-resolution aerogammaspectrometry survey for 232Th, 238U and 40K in main land near shore, used as primarily tool, in combination with sediment geochemistry. This approach allowed distinguishing three hydrographic basins (Macaé river basin, São João river basin and Una river basin) as potential sources. Hierarchical cluster analysis applied to the set of parameters identified the Macaé River as the most probable sediment contributor to the coralline site.

  3. Seroprevalence of Rickettsia bellii and Rickettsia felis in dogs, São José dos Pinhais, State of Paraná, Brazil.

    PubMed

    Fortes, Fernanda Silva; Silveira, Iara; Moraes-Filho, Jonas; Leite, Ronaldo Viana; Bonacim, José Edivaldo; Biondo, Alexander Welker; Labruna, Marcelo Bahia; Molento, Marcelo Beltrão

    2010-01-01

    Brazilian spotted fever (BSF) is a vector-borne zoonosis caused by Rickettsia rickettsii bacteria. Dogs can be host sentinels for this bacterium. The aim of the study was to determine the presence of antibodies against Rickettsia spp. in dogs from the city of São José dos Pinhais, State of Paraná, Southern Brazil, where a human case of BSF was first reported in the state. Between February 2006 and July 2007, serum samples from 364 dogs were collected and tested at 1:64 dilutions by indirect immunofluorescence assay (IFA) against R. rickettsii and R. parkeri. All sera that reacted at least to one of Rickettsia species were tested against the six main Rickettsia species identified in Brazil: R. rickettsii, R. parkeri, R. bellii, R. rhipicephali, R. amblyommii and R. felis. Sixteen samples (4.4%) reacted to at least one Rickettsia species. Among positive animals, two dogs (15.5%) showed suggestive titers for R. bellii exposure. One sample had a homologous reaction to R. felis, a confirmed human pathogen. Although Rickettsia spp. circulation in dogs in the area studied may be considered at low prevalence, suggesting low risk of human infection, the present data demonstrate for the first time the exposure of dogs to R. bellii and R. felis in Southern Brazil.

  4. [Ecological aspects of phlebotomus of the Parque Nacional da Serra dos Orgãos, Rio de Janeiro. I. Monthly frequency in human baits (Diptera, Psychodidae, Phlebotominae)].

    PubMed

    de Aguiar, G M; Soucasaux, T

    1984-01-01

    During two full years--from October 1980 to September 1982--we captured sandflies in the National Park of Serra dos Orgãos, State of Rio de Janeiro, Brazil. The captures, with human bait, were carried out weekly, each with a duration of two hours, and at three different times (6 to 8 a.m., 5 to 7 a.m. and 7:30 to 9:30 p.m.). In every capture, we recorded the phase of the moon and, at each hour, the temperature, relative humidity, wind and rain. In 586 hours 4,834 sandflies of ten species were captured, all belonging to genus Lutzomyia França, 1924. L. ayrozai and L. hirsuta represented 92% of the total species captured. However, they were dominant at different times, the former being more frequent in the warm and wet months, and considerably declining in the cold and dry months, in which the latter gradually prevailed. L. fischeri and L. shannoni were shown to be the most resistant to unfavourable weather conditions. Whenever there was any rain or wind, they were, in general, the only species captured. With regard to lunar cycle, we observed that new moon was the most favourable phase for the capture of sandflies and full moon the one with the smallest yield, except for L. shannoni which occurred more frequently during this period.

  5. Earth and Heavens: Two Separate Universes? (Spanish Title: Tierra y Cielos: ¿Dos Universos Separados?) Terra e Céus: Dois Universos Separados?

    NASA Astrophysics Data System (ADS)

    Carrascosa, Jaime; Gil-Pérez, Daniel; Solbes, Jordi; Vilches, Amparo

    2005-12-01

    complexidade, considerando, entre outros aspectos: as situações problemáticas relevantes que levaram à construção dos conhecimentos, as dificuldades de todo tipo que se teve que enfrentar nessa construção e, muito em particular,a necessidade de se superar as "evidências do senso comum" que estabeleciam uma suposta barreira intransponível entre a Terra e os Céus e que foram um obstáculo durante séculos para o desenvolvimento científico. Neste trabalho apresentamos um programa de atividades para o estudo da gravitação nos últimos anos do ensino médio, orientado a favorecer a participação dos estudantes, em alguma medida, na reconstrução deste processo que constituiu a denominada primeira grande revolução científica e a nos aproximarmos do estudo de uma das ciências mais antigas, a Astronomia, que hoje continua despertando grande interesse.

  6. Techniques of remote sensing applied to the environmental analysis of part of an aquifer located in the São José dos Campos Region sp, Brazil.

    PubMed

    Bressan, Mariana Affonseca; Dos Anjos, Célio Eustáquio

    2003-05-01

    The anthropogenic activity on the surface can modify and introduce new mechanisms of recharging the groundwater system, modifying the tax, the frequency and the quality of recharge of underground waters. The understanding of these mechanisms and the correct evaluation of such modifications are fundamental in determining the vulnerability of groundwater contamination. The groundwater flow of the South Paraíba Compartment, in the region of São José dos Campos, São Paulo, is directly related to structural features of the Taubaté Basin and, therefore, the analysis of its behaviour enhances the understanding of tectonic structure. The methodology adopted for this work consists in pre-processing and processing of the satellite images, visual interpretation of HSI products, field work and data integration. The derivation of the main structural features was based on visual analysis of the texture elements of drainage, and the relief in sedimentary and crystalline rocks. Statistical analysis of the feature densities and the metric-geometric relations between the analysed elements have been conducted. The crystalline rocks, on which the sediments were laying, conditions and controls the structural arrangement of sedimentary formations. The formation of the South Paraíba Grabén is associated with Cenozoic distensive movement which reactivated old features of crust weakness and generated previous cycles with normal characteristics. The environmental analysis is based on the integration of the existing methodology to characterise vulnerability of an universal pollutant and density fracture zone. The digital integration was processed using GIS (Geographic Information System) to delineate five defined vulnerability classes. The hydrogeological settings were analysed in each thematic map and, using fuzzy logic, an index for each different vulnerability class was compiled. Evidence maps could be combined in a series of steps using map algebra.

  7. [Governance, sustainability, and equity in the health program for the municipality of São José dos Pinhais, Brazil].

    PubMed

    Bueno, Roberto Eduardo; Moysés, Simone Tetu; Bueno, Paula Alexandra Reis; Moysés, Samuel Jorge

    2013-12-01

    To analyze the Final Report of the VIII Health Conference and the São José dos Pinhais City Health Program for 2010-2013 and investigate whether these documents addressed the themes of sustainability, governance, and equity and the interfaces between these themes--government policies, power balance, and inclusive processes/impacting results--that make up the Concept Model for Human Development and Health Promotion developed by the authors. This case study analyzed 331 proposals approved for incorporation in the City Health Program. The six thematical categories of the Concept Model were analyzed using ATLAS Ti 5.0 software. The proposals were classified according to the number of themes and interfaces of the Concept Model: full health proposals contained all six categories; partial proposals contained three categories; and incipient proposals contained one category. Of 331 proposals approved, 162 (49%) contemplated the six thematical categories and were classified as full health promotion proposals. Ninety-five (29%) contemplated three categories (partial health promotion). Of these, 38 (12%) addressed Governance, Sustainability, and Government Policies, 33 (10%) addressed Governance, Power Balance, and Equity and 24 (7%) addressed Equity, Inclusive Processes/Impact Results, and Sustainability. Finally, 74 (22%) proposals contemplated only one category and were classified as incipient: 36 (11%) addressed Governance, 27 (8%) addressed sustainability, and 11 (3%) addressed equity. Based on the fact that 49% of the proposals approved were classified as full health promotion, it is considered that the effectiveness of social control and popular participation in the construction of health policies at the local level contritute to the promotion of health in the city.

  8. Prevalence of intestinal parasites versus knowledge, attitudes, and practices of inhabitants of low-income communities of Campos dos Goytacazes, Rio de Janeiro State, Brazil.

    PubMed

    de Moraes Neto, Antonio Henrique A; Pereira, Adriana P M F; Alencar, Maria de Fátima L; Souza, Paulo R B; Dias, Rodrigo C; Fonseca, Juliana G; Santos, Clóvis P; Almeida, João C A

    2010-07-01

    Intestinal parasites are the causative agents of common infections responsible for significant public health problems in developing countries and generally linked to lack of sanitation, safe water, and improper hygiene. More than two billion people throughout the world live with unrelenting illness due to intestinal parasitic infections (IPIs). The purposes of this study are to assess knowledge, attitudes, and practices on IPIs and investigate the relationship with prevalence of intestinal parasites among a low-income group of inhabitants from two communities of the Travessão District area, Campos dos Goytacazes, north of Rio de Janeiro State, Brazil. The two communities are known as "Parque Santuário," which is an urban slum with miserable living conditions, and "Arraial," where the socioeconomic and educational levels are better, neither having a sanitary infrastructure with an excreta collection system. Questionnaires revealed that both communities had local and specific codification to denominate the intestinal parasites and present correct knowledge on the theme but ignored some aspects of IPI transmission, with the Arraial population being better informed (p < 0.05). The overall prevalence of IPIs in Parque Santuário (49.7%) was greater than in Arraial (27.2%) (p < 0.001; prevalence ratio/95% confidence interval 1.83/1.50-2.23). This study reports the real IPI situation in the Travessão District and also reinforces the need to continue the investigation on the impact of combined prophylactic methods, educational measures, and socioeconomic and sanitary improvements by governmental authorities and the local popular organization.

  9. Diverging DOS strategy using an allene-containing tryptophan scaffold and a library design that maximizes biologically relevant chemical space while minimizing the number of compounds.

    PubMed

    Painter, Thomas O; Wang, Lirong; Majumder, Supriyo; Xie, Xiang-Qun; Brummond, Kay M

    2011-03-14

    A diverging diversity-oriented synthesis (DOS) strategy using an allene-containing tryptophan as a key starting material was investigated. An allene-yne substituted derivative of tryptophan 12 gave indolylmethylazabicyclooctadiene 17 when subjected to a microwave-assisted allenic [2 + 2] cycloaddition reaction. This same tryptophan-derived precursor afforded an indolylmethyldihydrocyclopentapyridinone 14 when subjected to a rhodium(I)-catalyzed cyclocarbonylation reaction and an indolylmethylpyrrolidinocyclopentenones 16 when reacted with molybdenum hexacarbonyl. Construction of allenic tetrahydro-β-carboline scaffolds via a Pictet-Spengler reaction and subsequent silver(I)-catalyzed cycloisomerization afforded tetrahydroindolizinoindoles (21). Attachment of allene and alkyne groups to the tetrahydro-β-carboline, followed by a microwave-assisted allenic [2 + 2] cycloaddition reaction, provided tetrahydrocyclobutaindoloquinolizinones 24 and the tetrahydrocyclopentenone indolizinoindolone 26 when reacted with molybdenum hexacarbonyl. These six scaffolds were used as templates for the construction of a virtual library of 11 748 compounds employing 44 indoles, 12 aldehydes, and 51 alkynes. Diversity analyses using a combination of cell-based chemistry space computations using BCUT (Burden (B) CAS (C) Pearlman at the University of Texas (UT)) metrics and Tanimoto coefficient (Tc) similarity calculations using two-dimensional (2D) fingerprints showed that the compounds in the virtual library occupied new chemical space when compared to the 327,000 compounds in the molecular libraries small molecule repository (MLSMR). A subset of fifty-three compounds was identified from the virtual library using the DVS package of Sybyl 8.0; this subset represents the most diverse compounds within the chemical space defined by these compounds and will be synthesized and screened for biological activity.

  10. Estudio fotométrico y espectroscópico de dos cúmulos abiertos jóvenes del disco con apariencia globular

    NASA Astrophysics Data System (ADS)

    Piatti, A. E.; Clariá, J. J.; Bica, E.

    Se presentan y discuten resultados obtenidos en el CASLEO y en el Observatorio de Las Campanas de dos cúmulos abiertos compactos con apariencia globular: Westerlund1 (BH197), ubicado en dirección hacia el centro galáctico, y Westerlund2. A partir de espectroscopía CCD integrada de ambos e imágenes CCD en las bandas VI obtenidas para el primero de ellos, se derivan sus parámetros fundamentales y se examinan sus apariencias estructurales. Se encuentra que Westerlund1 es un cúmulo joven (7 ± 3 millones de años), ubicado sobre el plano galáctico a 1.0 ± 0.4 kpc del sol, en una región caracterizada por una absorción excepcionalmente elevada (Av~=13.0 mag), en tanto que Westerlund2 es también un cúmulo joven (4-6 millones de años) ubicado sobre el plano, en una región afectada por una absorción menor (Av~=5.7 mag). Desde el punto de vista estructural, Westerlund 1 se presenta como uno de los pocos cúmulos abiertos jóvenes de la Galaxia con apariencia tipicamente globular, en contraste con los cúmulos azules de las Nubes de Magallanes en los cuales la apariencia globular constituye un fenómeno común. Westerlund2, aunque menos rico en estrellas, puede también ser incluído dentro de esta interesante clase de objetos.

  11. Rb-Sr and Sm-Nd whole rock analyses of basalts of the Grao Para Group, Serra dos Carajas, Brazil

    SciTech Connect

    Olszewski, W.J. Jr.; Gibbs, A.K.; Wirth, K.R.

    1985-01-01

    The Grao Para Group at Serra dos Carajas in the Guapore Shield of Brazil is a 6 km thick sequence of bimodal metavolcanic rock with interbedded iron formations. Rhyolites are a minor part of the low grade meta-volcanic section, with the bulk consisting of subalkaline basalt, basaltic andesite, and shoshonite. Rb-Sr whole rock analyses of 7 basalts yield an age of 2687 +/- 54 Ma. This agrees well with an age of 2758 +/- 39 Ma from zircon U-Pb analyses of the interbedded rhyolites. Except for the allocthonous Imataca Complex of Venezuela, these dates for the Grao Para Group are the first well-constrained Archean ages from the Amazonian Craton. An even older age for the basement to the Grao Para Group is also implied. Sm-Nd whole-rock analyses of four of these basalts did not yield an isochron because of the limited range of /sup 147/Sm//sup 144/Nd values, but element of/sub Nd/ values relative to CHUR were calculated using the Rb-Sr age. The typical LREE-enrichment, lack of Ce depletion or spilitic alteration of alkalies, and the high Sr initial ratios, may indicate that these isotopic patterns were derived by incorporation of some older continental crust in the mafic melts. These data together with an element of/sub Sr/ of +63.6 might indicate significant seawater exchange with volcanic rocks derived from mantle with chondritic REE patterns. This demonstrates the presence of significant continental crust in the Archean and seawater-volcanic rock interaction in a rifting environment similar to modern analogs.

  12. Usefulness of triple-phase thallium-201 SPECT in non-small-cell lung cancer (NSCLC): association with proliferative activity.

    PubMed

    Fujita, Seigo; Nagamachi, Shigeki; Wakamatsu, Hideyuki; Nishii, Ryuichi; Futami, Shigemi; Tamura, Shozo; Matsuzaki, Yasunori; Onizuka, Toshio; Hatakeyama, Kinta; Asada, Yujiro

    2008-12-01

    The conventional delayed scan in dual phase of thallium-201 ((201)Tl) single-photon emission computed tomography (SPECT) is useful for estimating the viability of non-small-cell lung cancer (NSCLC). However, the influence of tumor blood flow cannot be ignored by the scan at 4 h after the tracer injection. For the purpose of improving the diagnostic capability and for clarifying the association between (201)Tl uptake and proliferative activity, we investigated the usefulness of super-delayed scan obtained at 24 h in triple-phase (201)Tl SPECT. A total of 122 patients with lung nodule, 106 of NSCLC and 16 of benign nodule, were given (201)Tl SPECT before the tumor resection. Early image (15 min), delayed image (4 h), and super-delayed image (24 h) were obtained after intravenous injection of (201)Tl chloride (111 MBq). On the each SPECT image, regions of interest (ROIs) were placed over the tumor contour (T) and contra-lateral normal lung tissue (N) area on one transverse view clearly defined lesions, and T/N ratio on the early image (ER), the delayed image (DR), and the super-delayed image (sDR), and retention indexes (RI and sRI) were calculated. All patients underwent subsequent surgical excision, and the specimens were immunostained for Ki-67 and CD34. The proliferative capability was measured as a percentage of positive nuclear area for Ki-67 (MIB-1 index). The angiogenesis was measured density of positive micro-vessels for CD34 (micro-vessel density, MVD). Correlation analysis was performed to evaluate the relationship between the MIB-1 index, MVD, and SPECT parameters. The diagnostic accuracy of sDR in the differential of NSCLC was higher than that of DR (83.6% vs. 91.8%). Both DR and sDR were positively correlated with MIB-1 index. The correlation coefficient was higher in sDR (0.53 vs. 0.69). The MIB-1 index of the increasing pattern (RI < sRI) group was significantly higher (P < 0.001) than that of the decreasing pattern (RI > sRI) group. The super

  13. Thallium-201 scintigraphy in bone and soft-tissue tumors: a comparison of dynamic, early and delayed scans.

    PubMed

    Sugawara, Yoshifumi; Kikuchi, Takanori; Kajihara, Makoto; Semba, Takatoshi; Ochi, Takashi; Fujii, Takashi; Mochizuki, Teruhito; Sakayama, Kenshi; Nakata, Shigeru

    2005-09-01

    It has been reported that delayed scan of thallium-201 (201Tl) scintigraphy is useful for differentiating malignant tumors from benign lesions and for evaluating treatment response. However, physiological muscle uptake which usually increases in delayed scans, often makes it difficult to evaluate 201Tl uptake and its washout in bone and soft-tissue tumors. The purpose of this study was to evaluate whether the delayed scan is necessary and whether a dynamic scan is useful in the evaluation of bone and soft-tissue tumors. We studied 175 cases of bone and soft-tissue tumors (malignant 45, benign 130). Dynamic scans were acquired every 5 seconds for 10 minutes after 201Tl injection, and time activity curves (TACs) were generated by adaptive smoothing methods. Early and delayed scans were acquired at 10-15 minutes and 2 hours after injection. 201Tl images were visually interpreted and the radioactivity count ratio (T/N) of tumors to normal tissues and washout rate [WR = (early T/N - delayed T/N)/early T/N] were defined. When there were no 201Tl uptake in dynamic (n = 67) and early scans (n = 68), no tumor uptake was also appreciated in delayed scans, and all but two cases of negative scans were benign. In 107 lesions, although there were significant differences in T/Ns between malignant and benign lesions both on early scans (2.84 +/- 1.45 vs. 2.05 +/- 1.13, p < 0.05) and delayed scans (2.17 +/- 1.03 vs. 1.58 +/- 0.64, p < 0.05), there was a substantial overlap. The T/Ns decreased in delayed scans (i.e., WR > 0) in 100 of 107 cases due to increase of surrounding muscle uptake, and there was no difference in WR between malignant tumors and benign lesions (0.21 +/- 0.14 vs. 0.19 +/- 0.14). For evaluating bone and soft-tissue tumors, delayed scan had little clinical usefulness and it may be time consuming. Dynamic scan would be useful for demonstrating the differences between tumor blood flow and 201Tl uptake in tumors.

  14. SU-E-T-115: Analysis of Patient Specific QA for VMAT by Disease Site and Planning-Delivery System Using the ScandiDos Delta4 Phantom

    SciTech Connect

    Giaddui, T; Hardin, M; Keller, J; Kremmel, E; Peng, C; Doyle, L; Yu, Y; Xiao, Y; Harrison, A; Fu, M

    2015-06-15

    Purpose: To evaluate patient specific quality assurance (PSQA) for the delivery of volumetric modulated arc therapy (VMAT) by disease site. To compare planning-delivery system (PDS) PSQA pass rates in a dual vendor institution. Methods: PSQA is performed for VMAT plans using a ScandiDos Delta4 phantom. Verification plans are calculated using Varian Eclipse and Elekta Monaco treatment planning systems (TPS) for patients treated using Varian Truebeam and Elekta linear accelerators respectively. Individual arcs are delivered to the Delta4 phantoms and assessed using the gamma index pass criterion(3% Dose Deviation(DD%), 3mm Distance to Agreement(DTA),10% dose threshold and 90% gamma index). Results: A total of 287 VMAT plans and 680 arcs were analyzed. The passing rates for VMAT QA plans were 95% and 98% for head/neck and pelvis/prostate plans respectively, and 100% for chest/abdomen, spine, lung Stereotactic Body Radiotherapy (SBRT) and Stereotactic Radiosurgery(SRS) plans. Average gamma indices were: (99 ± 2) % for pelvis/prostate, chest/abdomen and lung SBRT plans, (97 ± 4) % for head and neck plans and (98 ± 3) % for spine plans. The average DD% and DTA pass rates ranged from 82% to 90% and 98% to 99% respectively for plans in different disease sites. Paired t-test analysis (two tails) indicated no significant differences in the gamma indices between plans delivered using different PDS; the P values were: 0.08, 0.45, and 0.94 for lung SBRT, head/neck and pelvis/prostate plans respectively. The statistical power for comparing PDS in different disease sites with an alpha of 0.05 is 1. Conclusion: The Gamma indices based on 3% DD%, 3 mm DTA and 10% dose threshold for the VMAT QA plans in all disease sites were well above 90%, suggesting the possibility of using a more stringent PSQA criterion. No significant differences were observed in the QA of VMAT plans delivered using different PDS.

  15. Stratigraphy of fluvial sediment sequences and their palaeoenvironmental information in the foreland of the Serra dos Órgãos, southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Kirchner, André; Nehren, Udo; Heinrich, Jürgen

    2013-04-01

    In the hinterland of Rio de Janeiro city the rivers Guapiaçu, Macacu and Iconha originate in the Serra dos Órgãos mountain range and drain into the Atlantic Ocean. Since their channelization in the 1950s, higher flow velocities caused an incision of the rivers into the valley fills. These circumstances provide the possibility to study the alluvial deposits along the streams during low water level and allow conclusions on palaeoenvironmental change and landscape history. Sedimentological investigations of 13 exposures as well as AMS 14C measurements were carried out to investigate sediment properties and reconstruct the sedimentation history within the floodplains. These results enable to distinguish three different facies units. A late Pleistocene Unit I can be detected at the base of the observed exposures and consists of clast-supported fine to coarse gravels. It can be assumed that the gravel bodies were formed by a climatically induced erosional-depositional cycle within a braided river system. The gravels are overlaid by Unit II, a grayish to bluish loam mainly of mid-Holocene age. During generally drier climates these loams have been deposited during high water stages or flooding events as a splay facies proximal to the rivers. A reduced flow competence and relatively stable morphodynamic conditions are assumed for that period. Unit III accumulated in the late Holocene typically consists of several meters of planar or cross bedded sands to fine gravels, interfingered by loamy inclusions, buried peat bogs and organic debris. Fining-upward sequences can be frequently studied within Unit III which were completed by loamy sediments in the uppermost parts of the exposures. The increased flow competence from Unit II to Unit III seems to be a fluvial response to the increased humidity of the late Holocene as well as the enhancement of El Niño-Southern Oscillation (ENSO). Heavy rainfall likely caused higher sediment supply from the steep slopes as well as a

  16. The Serra Pelada Au-PGE deposit, Serra dos Carajás (Pará State, Brazil): geological and geochemical indications for a composite mineralising process

    NASA Astrophysics Data System (ADS)

    Moroni, Marilena; Girardi, Vicente A.; Ferrario, Alfredo

    2001-12-01

    The Serra Pelada Au-PGE-rich deposit is located in the Serra dos Carajás, a leading mining area in Brazil. This region is characterised by a complex geological and structural framework and is affected by deep lateritisation which has lasted for more than 70 Ma. The Serra Pelada deposit is emplaced in a late-Archean low-grade metasedimentary sequence (Rio Fresco/Águas Claras Formation) which is host to other gold deposits in the region (Igarapé Bahia, Águas Claras). The Rio Fresco/Águas Claras sequence was deposited in tectonic basins developed on Archean basement and Au-bearing greenstone terranes which were intruded by PGE-rich layered mafic complexes (e.g. Luanga). The Serra Pelada mineralisation is located along a regional, complex system of strike-slip faults (Cinzento-Carajás systems) which were active during the late Archean to early Proterozoic. The mineralisation appears to be concentrated along a faulted hinge zone of a fold. Ore zone rock facies are dominated by low-grade ferruginous to carbonaceous metasiltstones and minor sandstones, locally brecciated and cemented by quartz (±sulphide) stockwork. Supergene alteration led to partial to total transformation into friable aggregates of kaolinite, Fe oxide-hydroxides, silica and secondary phosphate-sulphates even at depths exceeding 200 m. Precious metals are exceptionally enriched, with up to more than 1,000 ppm Au+PGE in some peculiar ferruginous-graphitic zones locally called "hidrotermalito". Geochemistry shows complex patterns of major and trace elements, particularly rare-earth elements (REE), in mineralised vs. nonmineralised samples. These patterns are interpreted in terms of variable degree of superposition of hydrothermal and supergene alteration. Precious metals show progressive increase from samples with hydrothermal imprint to samples with supergene imprint. The geological evolution of the Carajás region and the characteristics of mineralisation at Serra Pelada may suggest a composite

  17. An interdisciplinary knowledge translation intervention in long-term care: study protocol for the vitamin D and osteoporosis study (ViDOS) pilot cluster randomized controlled trial.

    PubMed

    Kennedy, Courtney C; Ioannidis, George; Giangregorio, Lora M; Adachi, Jonathan D; Thabane, Lehana; Morin, Suzanne N; Crilly, Richard G; Marr, Sharon; Josse, Robert G; Lohfeld, Lynne; Pickard, Laura E; King, Susanne; van der Horst, Mary-Lou; Campbell, Glenda; Stroud, Jackie; Dolovich, Lisa; Sawka, Anna M; Jain, Ravi; Nash, Lynn; Papaioannou, Alexandra

    2012-05-24

    Knowledge translation (KT) research in long-term care (LTC) is still in its early stages. This protocol describes the evaluation of a multifaceted, interdisciplinary KT intervention aimed at integrating evidence-based osteoporosis and fracture prevention strategies into LTC care processes. The Vitamin D and Osteoporosis Study (ViDOS) is underway in 40 LTC homes (n = 19 intervention, n = 21 control) across Ontario, Canada. The primary objectives of this study are to assess the feasibility of delivering the KT intervention, and clinically, to increase the percent of LTC residents prescribed ≥800 IU of vitamin D daily. Eligibility criteria are LTC homes that are serviced by our partner pharmacy provider and have more than one prescribing physician. The target audience within each LTC home is the Professional Advisory Committee (PAC), an interdisciplinary team who meets quarterly. The key elements of the intervention are three interactive educational sessions led by an expert opinion leader, action planning using a quality improvement cycle, audit and feedback reports, nominated internal champions, and reminders/point-of-care tools. Control homes do not receive any intervention, however both intervention and control homes received educational materials as part of the Ontario Osteoporosis Strategy. Primary outcomes are feasibility measures (recruitment, retention, attendance at educational sessions, action plan items identified and initiated, internal champions identified, performance reports provided and reviewed), and vitamin D (≥800 IU/daily) prescribing at 6 and 12 months. Secondary outcomes include the proportion of residents prescribed calcium supplements and osteoporosis medications, and falls and fractures. Qualitative methods will examine the experience of the LTC team with the KT intervention. Homes are centrally randomized to intervention and control groups in blocks of variable size using a computer generated allocation sequence. Randomization is

  18. Geochemistry and petrogenesis of the Mesoarchean granites from the Canaã dos Carajás area, Carajás Province, Brazil: Implications for the origin of Archean granites

    NASA Astrophysics Data System (ADS)

    Feio, G. R. L.; Dall'Agnol, R.

    2012-12-01

    Four Mesoarchean (2.93 to 2.83 Ga) granite units, which encompass the Canaã dos Carajás, Bom Jesus, Cruzadão and Serra Dourada granites, were recognized in the Canaã dos Carajás area of the Archean Carajás Province. The Mesoarchean units are composed dominantly of biotite leucomonzogranites. They are compared with the Neoarchean Planalto suite (2.73 Ga) which encompasses biotite-hornblende monzogranites to syenogranites. The Canaã dos Carajás, Bom Jesus and the variety of the Cruzadão granite with higher (La/Yb)N are geochemically more akin to the calc-alkaline granites, whereas the other varieties of the Cruzadão granite are transitional between calc-alkaline and alkaline granites. The Serra Dourada granite has an ambiguous geochemical character with some features similar to those of calc-alkaline granites and other peraluminous granites. The Planalto granites have ferroan character, are similar geochemically to reduced A-type granites and show a strong geochemical contrast with the Mesoarchean studied granites. The Mesoarchean granites described in the Canaã dos Carajás area are geochemically distinct to those of the Rio Maria domain of the Carajás Province. The Canaã dos Carajás and Bom Jesus granites are similar to the high-Ca granites, whereas the Cruzadão and Serra Dourada are more akin to the low-CaO granites of the Yilgarn craton. The geochemical characteristics of the Mesoarchean studied granites approach those of the biotite granite group of Dharwar but the latter are enriched in HFSE and HREE compared to the Canaã dos Carajás granites. The Neoarchean Planalto suite granite has no counterpart in the Mesoarchean Rio Maria domain of the Carajás Province, neither in the Yilgarn and Dharwar cratons. Geochemical modeling suggests that partial melting of a source similar in composition to an Archean basaltic andesite of the Carajás Province could give origin to the Bom Jesus and Cruzadão granites. In the case of the Bom Jesus granite the

  19. Scintigraphic assessment of cardiac adrenergic innervation in patients with essential hypertension

    SciTech Connect

    Fujiwara, Y.; Hamada, M.; Shigematsu, Y.; Sumimoto, T.; Hamamoto, K.; Hiwada, K. )

    1991-01-01

    To assess the regional cardiac adrenergic innervation in patients with essential hypertension (EHT), simultaneous iodine-123 metaiodobenzylguanidine ((123I)MIBG) and thallium-201 (201Tl) myocardial imagings were performed in five patients with EHT, seven patients with hypertrophic cardiomyopathy (HCM), and seven normal subjects. Short axial images at rest were divided into five segments: anterior, septal, posterior, lateral, and apical segments. Percent regional uptake (%RU) of 201Tl except the septal segment in patients with EHT showed no significant difference. However, the %RU of (123I)MIBG at posterior, lateral, and apical segments was significantly lower than that at anterior and septal segments in EHT. This intraimage heterogeneity of (123I)MIBG was also observed in HCM. These results suggest that there is a difference in regional adrenergic innervation of the left ventricle with myocardial hypertrophy.

  20. Target preparation and recovery of enriched isotopes for medical radionuclide production

    NASA Astrophysics Data System (ADS)

    Lambrecht, Richard M.; Sajjad, Munawwar; Syed, Rashid H.; Meyer, William

    1989-10-01

    A remotely-driven internal target system with an improved stationary target head and manually controlled target transfer assembly was constructed. Methodology and techniques for the preparation of targets utilized for the routine production of 67Ga, 111In, 123I, 124I, and 201Tl with a CS-30 cyclotron are described. Experiences in recovery of isotopically enriched target materials are detailed for plating, radiochemical separation, and target recovery for 21 cycles with 68Zn; 18 cycles with 112Cd; 40 cycles with 124Te; and 24 cycles with 203Tl. This represented 84, 72, 145, and 196 targets for 67Ga, 111In, 123I + 124I, and 201Tl, respectively. Data on target stability under routine production conditions at high currents are summarized.

  1. Repeated 131I treatment of a residual ovarian teratoma containing malignant thyroid tissue.

    PubMed

    Suga, K; Hirabayashi, A; Motoyama, K; Kume, N; Matsunaga, N; Tamura, H; Kato, H

    1999-11-01

    A 49-year-old woman with ovarian teratoma received 131I treatment three times for an unresectable mass containing malignant thyroid tissue after surgery. Repeated 131I treatment effectively reduced serum thyroglobulin (Tg) level and tumour uptake of 131I, despite absence of any change in size of the treated tumour. Treatment did not inhibit the increase of serum CA-125 and tumour 201Tl uptake, associated with progression of a radioresistant intratumoral hyper-perfused tissue component, detected by colour Doppler ultrasound. Serum CA-125 level and tumour 201Tl uptake were not significantly changed despite temporary increases in serum Tg level after each 131I treatment. These observations indicate the importance of diagnostic measures using combined functional imaging and tumour markers in managing this rare tumour.

  2. Effects of adenosine and a selective A2A adenosine receptor agonist on hemodynamic and thallium-201 and technetium-99m-sestaMIBI biodistribution and kinetics.

    PubMed

    Mekkaoui, Choukri; Jadbabaie, Farid; Dione, Donald P; Meoli, David F; Purushothaman, Kailasnath; Belardinelli, Luiz; Sinusas, Albert J

    2009-10-01

    The purpose of this study was to compare a selective A(2A) adenosine receptor agonist (regadenoson) with adenosine in clinically relevant canine models with regard to effects on hemodynamics and thallium-201 ((201)Tl) and technetium-99m ((99m)Tc)-sestaMIBI biodistribution and kinetics. The clinical application of vasodilator stress for perfusion imaging requires consideration of the effects of these vasodilating agents on systemic hemodynamics, coronary flow, and radiotracer uptake and clearance kinetics. Sequential imaging and arterial blood sampling was performed on control, anesthetized closed-chest canines (n = 7) to evaluate radiotracer biodistribution and kinetics after either a bolus administration of regadenoson (2.5 microg/kg) or 4.5-min infusion of adenosine (280 microg/kg). The effects of regadenoson on coronary flow and myocardial radiotracer uptake were then evaluated in an open-chest canine model of a critical stenosis (n = 7). Results from ex vivo single-photon emission computed tomography were compared with tissue well-counting. The use of regadenoson compared favorably with adenosine in regard to the duration and magnitude of the hemodynamic effects and the effect on (201)Tl and (99m)Tc-sestaMIBI biodistribution and kinetics. The arterial blood clearance half-time was significantly faster for (99m)Tc-sestaMIBI (regadenoson: 1.4 +/- 0.03 min; adenosine: 1.5 +/- 0.08 min) than for (201)Tl (regadenoson: 2.5 +/- 0.16 min, p < 0.01; adenosine: 2.7 +/- 0.04 min, p < 0.01) for both vasodilator stressors. The relative microsphere flow deficit (0.34 +/- 0.02%) during regadenoson stress was significantly greater than the relative perfusion defect with (99m)Tc-sestaMIBI (0.69 +/- 0.03%, p < 0.001) or (201)Tl (0.53 +/- 0.02%, p < 0.001), although (201)Tl tracked the flow deficit within the ischemic region better than (99m)Tc-sestaMIBI. The perfusion defect score was larger with (201)Tl (22 +/- 2.8% left ventricular) than with (99m)Tc-sestaMIBI (17 +/- 1

  3. Noninvasive ergonovine maleate provocative testing for coronary artery spasm: the need for routine thallium-201 imaging

    SciTech Connect

    Shanes, J.G.; Krone, R.J.; Fisher, K.; Shah, B.; Eisenkramer, G.; Humphrey, J.R.

    1983-01-01

    We administered ergonovine and used both electrocardiographic monitoring and thallium-/sup 201/ (/sup 201/Tl) imaging to detect reversible ischemia in 100 patients. Patients already established as having coronary artery spasm and those with nonbypassed, proximal, high-grade coronary artery stenosis were excluded. No complication occurred in any patient. The use of thallium imaging in addition to electrocardiographic monitoring resulted in a higher degree of sensitivity than did ECG monitoring alone. Fourteen patients demonstrated evidence of coronary artery spasm as documented by /sup 201/Tl imaging but of the 14, significant ECG changes occurred in only 50%, and classic ST segment elevation in 21%. Thus, in carefully selected patients the noninvasive provocation of coronary spasm can be accomplished safely, but ECG monitoring must be combined with thallium-/sup 201/ imaging to achieve an acceptable degree of sensitivity.

  4. Development of a GSO detector assembly for a continuous blood sampling system

    NASA Astrophysics Data System (ADS)

    Kudomi, N.; Choi, Eunjoo; Yamamoto, S.; Watabe, H.; Kim, Kyeong Min; Shidahara, M.; Ogawa, M.; Teramoto, N.; Sakamoto, E.; Iida, H.

    2003-02-01

    A new input function monitoring system has been developed and evaluated using a GSO detector assembly for both PET and SPECT quantitative studies. Energy resolutions were 11% for 511 keV photons, 20% for 140 keV(/sup 99m/Tc) photons and 28% for 70 keV(/sup 201/Tl) photons, enabling the use of this system in SPECT studies. The paired assembly of crystals provided an absolute sensitivity of approximately 7% for PET tracers and 70% for /sup 99m/Tc and /sup 201/Tl (SPECT tracers). Multiple arrangement of paired detectors would make it possible to correct for the transit time of radioactivity through the catheter tube. This study demonstrates that the present system can be of use in both clinical and small animal studies using SPECT and PET tracers.

  5. Effect of collectivity on the nuclear level density

    NASA Astrophysics Data System (ADS)

    Roy, Pratap; Banerjee, K.; Gohil, M.; Bhattacharya, C.; Kundu, S.; Rana, T. K.; Ghosh, T. K.; Mukherjee, G.; Pandey, R.; Pai, H.; Srivastava, V.; Meena, J. K.; Banerjee, S. R.; Mukhopadhyay, S.; Pandit, D.; Pal, S.; Bhattacharya, S.

    2013-09-01

    Neutron evaporation spectra at backward angles from 201Tl*, 185Re*, and 169Tm* compound nuclei, having different ground-state deformations, have been measured at two excitation energies (E* ˜ 37 and 26 MeV). The values of the inverse level density parameter (k), extracted at these excitations using statistical model calculations, are observed to decrease substantially at the lower excitation energy (˜26 MeV) for nuclei having large ground-state deformation (residues of 185Re* and 169Tm*), whereas for near-spherical nuclei (residues of 201Tl*), the k value remains unchanged at the two energies. The decrease in k at the lower excitation energy for the deformed systems amounts to a relative increase in nuclear level density, indicating a collective enhancement. The present observation clearly establishes the existence of a strong correlation between collectivity and ground-state deformation.

  6. Reversible ischaemia of right ventricle detected by exercise thallium-201 scintigraphy.

    PubMed Central

    Lahiri, A; Carboni, G P; Crawley, J W; Raftery, E B

    1982-01-01

    Exercise and redistribution thallium-201 imaging is commonly used for the detection and evaluation of left ventricular ischaemia and infarction. The right ventricle is frequently visualised after stress and sometimes on redistribution images. The visualisation of the right ventricle at rest is thought to be abnormal and is suggestive of pressure or volume overload of the right ventricle, either a result of pulmonary hypertension or secondary to left ventricular dysfunction. Using stress and delayed 201Tl imaging we have shown reversible left and right ventricular ischaemia and fixed left ventricular perfusion defects in two patients with multivessel coronary artery disease and left ventricular dyskinesia caused by prior myocardial infarction. Judging by the rarity of this finding as well as taking into consideration 201Tl kinetics, it is suggested that reversible right ventricular ischaemia after exercise may only be detected in patients with coronary artery disease who have severely compromised ventricular function. This finding may have therapeutic and prognostic significance. Images PMID:7104119

  7. Abnormal thallium 201 scintigraphy during low-dose vasopressin infusions

    SciTech Connect

    Davison, R.; Kaplan, K.; Bines, A.; Spies, S.; Reed, M.T.; Lesch, M.

    1986-12-01

    Thallium 201 (/sup 201/Tl) myocardial scans were obtained in 16 patients just prior to the discontinuation of a vasopressin infusion (.1 to .2 units/min) administered for the treatment of upper gastrointestinal bleeding. Repeat scintigraphy was performed two to three hours after the vasopressin was stopped. Eleven of the 16 patients (69 percent) demonstrated areas of decreased myocardial /sup 201/Tl uptake that resolved after the infusion was stopped. Heart rate-blood pressure product was significantly lower at the time of the second scan. Autopsies were secured in three of 11 scan-positive patients: one had severe coronary artery obstruction, one nonsignificant disease, and another had normal coronary arteries. Vasopressin, even at low doses, can induce abnormalities in myocardial perfusion that are probably mediated by a direct effect on the coronary circulation. They are usually not detectable by routine monitoring techniques and conceivably form the basis for the cardiovascular morbidity associated with the use of this agent.

  8. Evaluation of the post-coronary artery bypass patient by myocardial perfusion scintigraphy and computed tomography

    SciTech Connect

    Engelstad, B.L.; Wagner, S.; Herfkens, R.; Botvinick, E.; Brundage, B.; Lipton, M.

    1983-09-01

    The clinical utility of /sup 201/Tl scintigraphy and of computed tomography for the noninvasive assessment of graft patency and regional myocardial perfusion was evaluated in 24 patients who had undergone aortocoronary bypass surgery. Perfusion defects on /sup 201/Tl scintigraphy (reversible or new, fixed) correlated (100% sensitivity, 78% specificity) with occlusion or stenosis of a graft or significant new native vessel disease. Graft occlusion was accurately demonstrated by dynamic computed tomography (100% sensitivity, 96% specificity) but did not uniformly correlate with regional perfusion. Perfusion defects in the distribution of patent grafts resulted from progressive native vessel disease or graft stenosis without complete occlusion. The absence of exercise-induced perfusion defects in regions of occluded grafts was attributed to suboptimal exercise, collateralization, or noncritical native vessel stenosis. The two studies provide complementary anatomic and physiologic information in the evaluation of the postbypass patient.

  9. Imaging considerations for a technetium-99m myocardial perfusion agent

    SciTech Connect

    English, R.J.; Jones, A.G.; Davison, A.; Lister-James, J.; Campbell, S.; Holman, B.L.

    1986-03-01

    Myocardial perfusion imaging with /sup 201/Tl chloride suffers from a number of physical, geometric, and dosimetric constraints that could be diminished if an agent labeled with /sup 99m/Tc were available. The cationic complex /sup 99m/Tc hexakis-(t-butylisonitrile)technetium(I) ((/sup 99m/Tc)TBI) has been shown to concentrate in the myocardial tissue of both animals and humans, with preliminary clinical studies demonstrating a number of technical attributes not possible with /sup 201/Tl. Technetium-99m-TBI is a promising myocardial imaging agent that may permit high quality planar, gated, and tomographic imaging of both myocardial ischemia and infarction with reduced imaging times and improved resolution.

  10. Caffeine reduces dipyridamole-induced myocardial ischemia

    SciTech Connect

    Smits, P.; Aengevaeren, W.R.; Corstens, F.H.; Thien, T. )

    1989-10-01

    The mechanism of action of coronary vasodilation after dipyridamole may be based on inhibition of cellular uptake of circulating endogenous adenosine. Since caffeine has been reported to be a competitive antagonist of adenosine we studied the effect of caffeine on the outcome of dipiridamole-{sup 201}Tl cardiac imaging in one patient. During caffeine abstinence dipyridamole induced myocardial ischemia with down-slope ST depressions on the ECG, and reversible perfusion defects on the scintigrams. When the test was repeated 1 wk later on similar conditions, but now shortly after infusion of caffeine (4 mg/kg), the ECG showed nodepressions, and the scintigrams only slight signs of ischemia. We conclude that when caffeine abstinence is not sufficient, the widespread use of coffee and related products may be responsible for false-negative findings in dipyridamole-201Tl cardiac imaging.

  11. Tomographic myocardial perfusion scintigraphy in children with Kawasaki disease

    SciTech Connect

    Spielmann, R.P.; Nienaber, C.A.; Hausdorf, G.; Montz, R.

    1987-12-01

    Myocardial infarction and stenotic coronary lesions are serious late complications in children with Kawasaki disease. For the noninvasive assessment of myocardial perfusion, dipyridamole-redistribution /sup 201/Tl emission computed tomography (ECT) was performed in seven children (age 2 8/12-8 7/12 yr) 3-20 mo after the acute stage of the disease. In all patients, coronary aneurysms had been demonstrated by cross-sectional echocardiography. The scintigrams of six children showed no significant regional reduction of myocardial thallium uptake. These children had remained asymptomatic since the acute stage of Kawasaki disease. Persistent and transient thallium defects were present in one child with documented myocardial infarction. For this patient, obstruction of corresponding coronary vessels was confirmed by contrast angiography. It is suggested, that /sup 201/Tl ECT after dipyridamole-induced vasodilation may be used as a safe alternative to invasive coronary angiography for follow-up investigations in patients with Kawasaki disease.

  12. Investigação dos perfís temporais de alta resolução de explosões solares tipo-III decimétricas

    NASA Astrophysics Data System (ADS)

    Cecatto, J. R.; Fernandes, F. C. R.; Sawant, H. S.; Madsen, F. R. H.

    2003-08-01

    Explosões solares tipo-III indicam a presença de feixes de elétrons acelerados durante "flares" solares. Sua investigação fornece informações tanto sobre os processos de aceleração de partículas quanto das características do agente causador e do local de aceleração. Explosões tipo-III decimétricas são geradas por feixes de elétrons viajando através de arcos magnéticos densos da baixa coroa solar. Os perfís temporais destes fenômenos, quando tomados com alta resolução, informam sobre os mecanismos de aceleração de partículas do feixe e o meio de transporte da energia liberada a partir da região de aceleração. Usando o Brazilian Solar Spectroscope (BSS), em operação no INPE, foram registradas dezenas de explosões tipo-III decimétricas, dentro da faixa de 2050-2250 MHz com alta resolução temporal (20 ms), em 13 de setembro de 2001, entre 13:00 e 16:10 UT. Foram selecionadas 10 explosões isoladas para uma investigação estatística detalhada de seus perfís temporais, em todos os cerca de 50 canais de freqüência. Os resultados indicam que cerca de 70% dos perfís temporais são complexos tanto durante a subida quanto descida. Os 30% restantes indicam que os perfís da subida podem ser bem representados, na maioria dos casos, por um processo não-linear e uma parcela significativa por processos lineares. Os perfís temporais da descida são dominados por um decaimento não-linear. Neste trabalho, será efetuada uma análise dos perfís temporais, tanto durante a subida quanto descida do fluxo, para as explosões selecionadas, em termos dos prováveis mecanismos de aceleração e relaxamento. 2

  13. Prevalence and prognostic significance of exercise-induced silent myocardial ischemia detected by thallium scintigraphy and electrocardiography in asymptomatic volunteers

    SciTech Connect

    Fleg, J.L.; Gerstenblith, G.; Zonderman, A.B.; Becker, L.C.; Weisfeldt, M.L.; Costa, P.T. Jr.; Lakatta, E.G. )

    1990-02-01

    Although a silent ischemic electrocardiographic response to treadmill exercise in clinically healthy populations is associated with an increased likelihood of future coronary events (i.e., angina pectoris, myocardial infarction, or cardiac death), such a response has a low predictive value for future events because of the low prevalence of disease in asymptomatic populations. To examine whether detection of reduced regional perfusion by thallium scintigraphy improved the predictive value of exercise-induced ST segment depression, we performed maximal treadmill exercise electrocardiography (ECG) and thallium scintigraphy (201Tl) in 407 asymptomatic volunteers 40-96 years of age (mean = 60) from the Baltimore Longitudinal Study on Aging. The prevalence of exercise-induced silent ischemia, defined by concordant ST segment depression and a thallium perfusion defect, increased more than sevenfold from 2% in the fifth and sixth decades to 15% in the ninth decade. Over a mean follow-up period of 4.6 years, cardiac events developed in 9.8% of subjects and consisted of 20 cases of new angina pectoris, 13 myocardial infarctions, and seven deaths. Events occurred in 7% of individuals with both negative 201Tl and ECG, 8% of those with either test positive, and 48% of those in whom both tests were positive (p less than 0.001). By proportional hazards analysis, age, hypertension, exercise duration, and a concordant positive ECG and 201Tl result were independent predictors of coronary events. Furthermore, those with positive ECG and 201Tl had a 3.6-fold relative risk for subsequent coronary events, independent of conventional risk factors.

  14. Effects of CT-based attenuation correction of rat microSPECT images on relative myocardial perfusion and quantitative tracer uptake

    SciTech Connect

    Strydhorst, Jared H. Ruddy, Terrence D.; Wells, R. Glenn

    2015-04-15

    Purpose: Our goal in this work was to investigate the impact of CT-based attenuation correction on measurements of rat myocardial perfusion with {sup 99m}Tc and {sup 201}Tl single photon emission computed tomography (SPECT). Methods: Eight male Sprague-Dawley rats were injected with {sup 99m}Tc-tetrofosmin and scanned in a small animal pinhole SPECT/CT scanner. Scans were repeated weekly over a period of 5 weeks. Eight additional rats were injected with {sup 201}Tl and also scanned following a similar protocol. The images were reconstructed with and without attenuation correction, and the relative perfusion was analyzed with the commercial cardiac analysis software. The absolute uptake of {sup 99m}Tc in the heart was also quantified with and without attenuation correction. Results: For {sup 99m}Tc imaging, relative segmental perfusion changed by up to +2.1%/−1.8% as a result of attenuation correction. Relative changes of +3.6%/−1.0% were observed for the {sup 201}Tl images. Interscan and inter-rat reproducibilities of relative segmental perfusion were 2.7% and 3.9%, respectively, for the uncorrected {sup 99m}Tc scans, and 3.6% and 4.3%, respectively, for the {sup 201}Tl scans, and were not significantly affected by attenuation correction for either tracer. Attenuation correction also significantly increased the measured absolute uptake of tetrofosmin and significantly altered the relationship between the rat weight and tracer uptake. Conclusions: Our results show that attenuation correction has a small but statistically significant impact on the relative perfusion measurements in some segments of the heart and does not adversely affect reproducibility. Attenuation correction had a small but statistically significant impact on measured absolute tracer uptake.

  15. Nuclear data calculation methods for medical applications

    SciTech Connect

    Shubin, Yu.N.; Lunev, V.P.; Masterov, V.S.; Kurenkov, N.V.; Kulikov, E.V.

    1994-12-31

    Neutron deficient radionuclides play an important role in medicine, where they are used for diagnostic with Positron Emission Tomography (PET) and Single Photon Emission Tomography (SPET). Using some reactions connected with the producing most widely used radioisotopes {sup 123}I, {sup 201}Tl, {sup 99}Tc as example we calculated reaction cross sections and discuss the possibilities of the models and codes and recent progress in the methods to predict nuclear data for medical and other applications in medium energy region.

  16. Intercomparisons for quality assurance of activity measurements with radionuclide calibrators

    NASA Astrophysics Data System (ADS)

    Debertin, K.; Schrader, H.

    1992-02-01

    Several intercomparisons with up to 82 participants have been organized in order to obtain information on the quality of activity measurements of radiopharmaceuticals with radionuclide calibrators ("activimeters") in nuclear medicine. The following radionuclides were chosen: 99mTc, 99mTc(99.9%) + 99Mo(0.1%), 123I, 131I and 201Tl. The error limits given in the European Pharmacopoeia were exceeded in about one third of the reported activity values.

  17. Vasospastic exercise-associated unilateral leg ischemia: evaluation with thallium-201

    SciTech Connect

    Hartshorne, M.F.; Peters, V.; Williams, R.D.; Bauman, J.M.; Cawthon, M.A.; Timmons, J.

    1987-01-01

    Thallium 201 (Tl-201) as a marker of regional tissue perfusion is described as a diagnostic aid in a case of exercise-induced vasospastic disease affecting the lower leg of a physically active young adult male who had no evidence of atherosclerotic disease. The success and failure of various therapeutic attempts made in behalf of this patient have been monitored by repeated Tl-201 administrations. Exercise-associated ischemia in tissues other than the myocardium can be investigated with Tl-201.

  18. Effects of heart rate on myocardial thallium-201 uptake and clearance

    SciTech Connect

    Nordrehaug, J.E.; Danielsen, R.; Vik-Mo, H. )

    1989-12-01

    The effects of heart rate on the myocardial uptake and clearance of {sup 201}Tl were studied prospectively in seven healthy men, mean age 43 +/- 7 (s.d.) yr. Initial and delayed (3 hr) thallium images were obtained in three views after three bicycle exercise tests: to maximal, 80% and 60% of predicted maximal heart rate. The mean of three views initial myocardial {sup 201}Tl uptake was higher at maximal than at both 80% and 60% of predicted maximal heart rate, being 81% (p less than 0.01) and 60% (p less than 0.01) of maximal activity, respectively. The myocardial activity in the delayed images was identical. There was a linear relationship between heart rate and the initial myocardial activity, r = 0.86 (p less than 0.001). The mean (range) {sup 201}Tl clearance was 58% (51-65), 47% (34-56), and 34% (22-49) (all differences p less than 0.01), respectively. Concordance among the three individual views in estimating clearance was best for the highest exercise level. There was a linear relationship between heart rate and clearance, r = 0.80 (p less than 0.001). Clearance was altered by only 1.67 x 10%/heart bpm (0.024 hr/heart beat). Clearance in the liver, spleen and lungs increased at submaximal exercise levels. Thus, a linear relationship between heart rate and clearance is the result of changes in the initial exercise myocardial {sup 201}Tl activity. Submaximal exercise may reduce reproducibility of clearance estimation, and the change of myocardial clearance with heart rate seems less than previously suggested.

  19. Semiquantitative analysis using thallium-201 SPECT for differential diagnosis between tumor recurrence and radiation necrosis after gamma knife surgery for malignant brain tumors.

    PubMed

    Matsunaga, Shigeo; Shuto, Takashi; Takase, Hajime; Ohtake, Makoto; Tomura, Nagatsuki; Tanaka, Takahiro; Sonoda, Masaki

    2013-01-01

    Semiquantitative analysis of thallium-201 chloride single photon emission computed tomography (201Tl SPECT) was evaluated for the discrimination between recurrent brain tumor and delayed radiation necrosis after gamma knife surgery (GKS) for metastatic brain tumors and high-grade gliomas. The medical records were reviewed of 75 patients, including 48 patients with metastatic brain tumor and 27 patients with high-grade glioma who underwent GKS in our institution, and had suspected tumor recurrence or radiation necrosis on follow-up neuroimaging and deteriorating clinical status after GKS. Analysis of 201Tl SPECT data used the early ratio (ER) and the delayed ratio (DR) calculated as tumor/normal average counts on the early and delayed images, and the retention index (RI) as the ratio of DR to ER. A total of 107 tumors were analyzed with 201Tl SPECT. Nineteen lesions were removed surgically and histological diagnoses established, and the other lesions were evaluated with follow-up clinical and neuroimaging examinations after GKS. The final diagnosis was considered to be recurrent tumor in 65 lesions and radiation necrosis in 42 lesions. Semiquantitative analysis demonstrated significant differences in DR (P=.002) and RI (P<.0001), but not in ER (P=.372), between the tumor recurrence and radiation necrosis groups, and no significant differences between metastatic brain tumors and high-grade gliomas in all indices (P=.926 for ER, P=.263 for DR, and P=.826 for RI). Receiver operating characteristics analysis indicated that RI was the most informative index with the optimum threshold of 0.775, which provided 82.8% sensitivity, 83.7% specificity, and 82.8% accuracy. Semiquantitative analysis of 201Tl SPECT provides useful information for the differentiation between tumor recurrence and radiation necrosis in metastatic brain tumors and high-grade gliomas after GKS, and the RI may be the most valuable index for this purpose. Copyright © 2013 Elsevier Inc. All rights

  20. MRI and thallium-201 SPECT in the prediction of survival in glioma.

    PubMed

    Vos, Maaike J; Berkhof, Johannes; Hoekstra, Otto S; Bosma, Ingeborg; Sizoo, Eefje M; Heimans, Jan J; Reijneveld, Jaap C; Sanchez, Esther; Lagerwaard, Frank J; Buter, Jan; Noske, David P; Postma, Tjeerd J

    2012-06-01

    This paper aims to study the value of MRI and Thallium 201 ((201)Tl) single-photon emission computed tomography (SPECT) in the prediction of overall survival (OS) in glioma patients treated with temozolomide (TMZ) and to evaluate timing of radiological follow-up. We included patients treated with TMZ chemoradiotherapy for newly diagnosed glioblastoma multiforme (GBM) and with TMZ for recurrent glioma. MRIs and (201)Tl SPECTs were obtained at regular intervals. The value of both imaging modalities in predicting OS was examined using Cox regression analyses. Altogether, 138 MRIs and 113 (201)Tl SPECTs in 46 patients were performed. Both imaging modalities were strongly related to OS (P ≤ 0.02). In newly diagnosed GBM patients, the last follow-up MRI (i.e., after six adjuvant TMZ courses) and SPECT (i.e., after three adjuvant TMZ courses) were the strongest predictors of OS (P = 0.01). In recurrent glioma patients, baseline measurements appeared to be the most predictive of OS (P < 0.01). The addition of one imaging modality to the other did not contribute to the prediction of OS. Both MRI and (201)Tl SPECT are valuable in the prediction of OS. It is adequate to restrict to one of both modalities in the radiological follow-up during treatment. In the primary GBM setting, MRI after six adjuvant TMZ courses contributes significantly to the prediction of survival. In the recurrent glioma setting, baseline MRI appears to be a powerful predictor of survival, whereas follow-up MRIs during TMZ seem to be of little additional value.

  1. Semiquantitative Analysis Using Thallium-201 SPECT for Differential Diagnosis Between Tumor Recurrence and Radiation Necrosis After Gamma Knife Surgery for Malignant Brain Tumors

    SciTech Connect

    Matsunaga, Shigeo; Shuto, Takashi; Takase, Hajime; Ohtake, Makoto; Tomura, Nagatsuki; Tanaka, Takahiro; Sonoda, Masaki

    2013-01-01

    Purpose: Semiquantitative analysis of thallium-201 chloride single photon emission computed tomography ({sup 201}Tl SPECT) was evaluated for the discrimination between recurrent brain tumor and delayed radiation necrosis after gamma knife surgery (GKS) for metastatic brain tumors and high-grade gliomas. Methods and Materials: The medical records were reviewed of 75 patients, including 48 patients with metastatic brain tumor and 27 patients with high-grade glioma who underwent GKS in our institution, and had suspected tumor recurrence or radiation necrosis on follow-up neuroimaging and deteriorating clinical status after GKS. Analysis of {sup 201}Tl SPECT data used the early ratio (ER) and the delayed ratio (DR) calculated as tumor/normal average counts on the early and delayed images, and the retention index (RI) as the ratio of DR to ER. Results: A total of 107 tumors were analyzed with {sup 201}Tl SPECT. Nineteen lesions were removed surgically and histological diagnoses established, and the other lesions were evaluated with follow-up clinical and neuroimaging examinations after GKS. The final diagnosis was considered to be recurrent tumor in 65 lesions and radiation necrosis in 42 lesions. Semiquantitative analysis demonstrated significant differences in DR (P=.002) and RI (P<.0001), but not in ER (P=.372), between the tumor recurrence and radiation necrosis groups, and no significant differences between metastatic brain tumors and high-grade gliomas in all indices (P=.926 for ER, P=.263 for DR, and P=.826 for RI). Receiver operating characteristics analysis indicated that RI was the most informative index with the optimum threshold of 0.775, which provided 82.8% sensitivity, 83.7% specificity, and 82.8% accuracy. Conclusions: Semiquantitative analysis of {sup 201}Tl SPECT provides useful information for the differentiation between tumor recurrence and radiation necrosis in metastatic brain tumors and high-grade gliomas after GKS, and the RI may be the most

  2. Radionuclide imaging in myocardial sarcoidosis. Demonstration of myocardial uptake of /sup 99m/Tc pyrophosphate and gallium

    SciTech Connect

    Forman, M.B.; Sandler, M.P.; Sacks, G.A.; Kronenberg, M.W.; Powers, T.A.

    1983-03-01

    A patient had severe congestive cardiomyopathy secondary to myocardial sarcoidosis. The clinical diagnosis was confirmed by radionuclide ventriculography, /sup 201/Tl, /sup 67/Ga, and /sup 99m/Tc pyrophosphate (TcPYP) scintigraphy. Myocardial TcPYP uptake has not been reported previously in sarcoidosis. In this patient, TcPYP was as useful as gallium scanning and thallium imaging in documenting the myocardial process.

  3. Quantitative analysis of sup 123 I-meta-iodobenzylguanidine (MIBG) uptake in hypertrophic cardiomyopathy

    SciTech Connect

    Nakajima, K.; Bunko, H.; Taki, J.; Shimizu, M.; Muramori, A.; Hisada, K. )

    1990-06-01

    Myocardial scintigraphy with 123I-meta-iodobenzylguanidine (MIBG) and thallium-201 (201Tl) was performed in 29 patients with hypertrophic cardiomyopathy (HCM) using whole-body scintigraphy and single-photon emission computed tomography (SPECT). Nonhypertensive patients were classified into three groups according to the septal thickness determined by ultrasonography; group 1 (wall thickness less than 16 mm, n = 5), group 2 (from 16 to 20 mm, n = 12) and group 3 (greater than 20 mm, n = 4). The regional myocardial uptakes of both 201Tl and 123I-MIBG (percent of injected dose/cm3 myocardium) were higher in the more hypertrophic septa. However, when regional MIBG uptake at 3 hours was divided by the 201Tl uptake to calculate the MIBG uptake per unit of blood flow, the hypertrophic septa showed lower mean values--0.39 +/- 0.23 and 0.50 +/- 0.10 in groups 3 and 2, respectively (p less than 0.1 compared with 0.69 +/- 0.20 in group 1). The regional MIBG clearance rate in the septum was significantly higher in group 3 compared with group 1 (13.4 +/- 8.0%/hr versus 1.5 +/- 6.2%/hr, p less than 0.05). The uptake and 123I-MIBG clearance rate in the lateral wall showed a similar tendency. Myocardial uptake determined by whole-body scintigraphy was slightly increased in group 2 (3.5 +/- 0.6%, p less than 0.05) compared with group 1 (2.7 +/- 0.8%); however, it was lower in group 3 (2.7 +/- 0.4%). Myocardial 123I-MIBG distribution demonstrated various patterns in comparison with 201Tl distribution, suggesting that flow-independent changes in sympathetic innervation or activity may exist in patients with HCM.

  4. Diagnostic accuracy of supine and prone thallium-201 stress myocardial perfusion single-photon emission computed tomography to detect coronary artery disease in inferior wall of left ventricle.

    PubMed

    Katayama, Takuji; Ogata, Nobuhiko; Tsuruya, Yoshio

    2008-05-01

    Prone thallium-201 ((201)Tl) myocardial perfusion single-photon emission computed tomography (SPECT) reduces false-positive rates when evaluating inferior wall abnormalities by minimizing diaphragmatic attenuation. The present study investigates the diagnostic validity of prone (201)Tl stress myocardial perfusion SPECT for detecting coronary artery disease in the inferior wall of the left ventricle in Japanese patients. Of the 104 consecutive patients who underwent (201)Tl stress myocardial perfusion SPECT to diagnose coronary artery disease, we evaluated 46 who underwent image acquisition in both the supine and prone positions, and coronary angiography within 3 months thereafter. Images were acquired in the routine supine position immediately following (201)Tl (111 MBq) injection and 4 h following early acquisition. Images were acquired in the prone position only during the early phase following supine acquisition. We evaluated the SPECT images of the inferior half segments of the left ventricle using a five-point defect scoring system. According to the coronary angiographic findings, we investigated the diagnostic accuracy of stress-rest supine, stress supine, stress prone, and combined supine-prone images. Reduced uptake in the stress supine image of the combined images was considered as attenuation when uptake was normal in the prone image. The sensitivity of the stress-rest supine, stress supine, stress prone, and stress-combined supine-prone images was 77%, 86%, 55%, and 55%, and the specificity was 71%, 54%, 79%, and 83%, respectively. Diagnostic accuracy was the highest in stress-rest supine images. Prone images tended to improve the specificity of detecting coronary artery disease in the inferior wall, but not diagnostic accuracy compared with stress-rest supine images because of decreased sensitivity.

  5. Defect images in stress thallium-201 myocardial scintigraphy in patients with complete left bundle branch block: comparison of exercise stress and pharmacological stress.

    PubMed

    Sasaki, Hideki; Shimizu, Mitsuyuki; Ogawa, Kazuhiko; Okazaki, Fumiko; Mizokami, Tsuneo; Kusaka, Masafumi; Uehara, Yoshiki; Taniguchi, Ikuo; Mochizuki, Seibu

    2007-04-01

    Stress thallium-201 (201Tl) myocardial scintigraphy can demonstrate perfusion abnormalities, especially in the septum in patients with complete left bundle branch block (CLBBB) even with angiographically normal coronary arteries. Differences in the images between exercise and pharmacological stress 201Tl myocardial scintigraphy were evaluated in patients with CLBBB and normal coronary arteries. Forty-five patients with CLBBB underwent exercise stress using treadmill or pharmacological (adenosine triphosphate) stress 201Tl myocardial scintigraphy from October 1997 to February 2003. Patients with myocardial diseases were excluded, such as cardiomyopathy and coronary artery diseases detected by echocardiography and/or cardiac catheterization. The myocardial segment was classified according to the American Heart Association style for coronary artery disease. Peak blood pressure levels and heart rates were significantly higher in the exercise stress group than in the pharmacological stress group (p < 0.001). The rate of defects in stress images was significantly higher in the exercise stress group (72.4%; 21/29 cases) than in the pharmacological stress group (18.8%; 3/16 cases) (p < 0.01). The rate of redistribution of observed defects in delayed images was 76.2% (16/21 cases) in the exercise stress group, and 0% (0/3 cases)in the pharmacological stress group (p < 0.01). The myocardial segments showing defects were different between the exercise stress group and the pharmacological stress group. Patients with CLBBB showed different frequencies of defects by stress 201Tl myocardial scintigraphy according to the stress method. Moreover, defects also occured in areas other than the septum. Blood pressure and heart rate were involved in the mechanisms of defects in left bundle branch block.

  6. Detection of right ventricular pressure overloading by thallium-201 myocardial scintigraphy. Results in 57 patients with chronic respiratory diseases

    SciTech Connect

    Weitzenblum, E.; Moyses, B.; Dickele, M.C.; Methlin, G.

    1984-02-01

    The diagnostic value of thallium 201 (/sup 201/Tl) myocardial imaging was studied in 57 patients with chronic respiratory diseases, most with COPD (n . 46), by comparing the results to hemodynamic findings. In healthy subjects, the right ventricle (RV) is not visualized; therefore, any recorded activity of the RV was considered as indicating RV hypertrophy due to RV pressure overloading (RVPO). RV activity was graded from 0 (no activity) to 3 (activity greater than or equal to that of the left ventricle). Patients were divided into three groups according to the level of the pulmonary artery mean pressure (PPA): PPA less than or equal to 20 mm Hg (no pulmonary arterial hypertension (PAH) ) . group 1, n . 20; PPA ranging from 21 to 30 mm Hg (mild to moderate PAH) . group 2, n . 20; PPA greater than 30 mm Hg (marked PAH) . group 3, n . 17. RV was visualized in 14 patients in group 3 (82 percent) and in 13 patients in group 2 (65 percent). For all patients with PAH (2 + 3) the sensitivity of /sup 201/Tl imaging for the diagnosis of RVPO was of 73 percent, higher than that of ECG and echocardiography (both 51 percent). The sensitivity of /sup 201/Tl, even if moderate (65 percent) was better than that of ECG (30 percent) or echo (40 percent) in patients with mild-to-moderate PAH (group 2). A high RV activity (grade 3) was observed in only three patients. The specificity of this method (obtained from results in group 1) was of 80 percent vs 89 percent for echo and 100 percent for ECG. These results suggest that 201Tl myocardial imaging is a rather sensitive method and could be of interest for the noninvasive diagnosis of RVPO in COPD patients.

  7. The comparison of 2-18F-2-deoxyglucose and 15-(ortho-123I-phenyl)-pentadecanoic acid uptake in persisting defects on thallium-201 tomography in myocardial infarction

    SciTech Connect

    Henrich, M.M.; Vester, E.; von der Lohe, E.; Herzog, H.; Simon, H.; Kuikka, J.T.; Feinendegen, L.E. )

    1991-07-01

    The myocardial uptake of glucose and fatty acids into 201Tl redistribution defects were studied in 32 patients with myocardial infarction by tomography using 2-18F-2-deoxyglucose (FDG) and 15-(ortho-123I-phenyl)-pentadecanoic acid (oPPA). A total of 1153 segments were analyzed, 408 (35%) of which showed a persistent thallium-defect in stress-redistribution images. Of the segments with a decreased 201Tl uptake in these redistribution tomograms, 50.5% had a decreased uptake of both FDG and oPPA; in 21.8% FDG as well as oPPA uptake was within normal range. Normal FDG uptake but decreased oPPA uptake was detected in 17.4%, whereas 10.3% of the segments had normal oPPA uptake but decreased FDG uptake (chi-square test, p less than 0.001). A significant correlation of FDG and oPPA uptake (r = 0.51) was found in the segments with persistent 201Tl defect. Thus, a substantial fraction of persistent thallium-defects after healed myocardial infarction exhibit FDG as well as oPPA uptake, probably due to residual fatty acid metabolism in partially ischemic regions.

  8. Tomographic thallium-201 myocardial perfusion scintigrams after maximal coronary artery vasodilation with intravenous dipyridamole: comparison of qualitative and quantitative approaches

    SciTech Connect

    Francisco, D.A.; Collins, S.M.; Go, R.T.; Ehrhardt, J.C.; Van Kirk, O.C.; Marcus, M.L.

    1982-08-01

    Eighty-six patients had thallium-201 (/sup 201/Tl) myocardial perfusion scintigrams after intense coronary artery dilation with i.v. dipyridamole. Tomographic and planar /sup 201/Tl scintigrams were obtained in each patient. Tomographic scintigrams were interpreted using quantitative or visual criteria; planar scintigrams were assessed using visual criteria only. When visual criteria were used, interobserver variability was 40% for tomographic scintigrams and 44% for planar scintigrams. In the 24 patients with normal or nonsignificant CAD, quantitative analysis of the tomograms (range approach) indicated that one of 24 (4%) had a positive image (specificity 96%%); in contrast, when visual criteria were used to interpret the tomographic or planar /sup 201/Tl scintigrams, eight of 24 (33%) had positive scintigrams (specificity 67%). In the 51 abnormal patients, the sensitivity of detecting CAD was 46 of 51 (90%) for tomographic scintigrams interpreted quantitatively, 39 of 51 (76%) for tomographic scintigrams interpreted visually and 41 of 51 (80%) for planar scintigrams assessed visually. The tomographic imaging procedure (quantitative interpretation) also demonstrated a high sensitivity (89%) and specificity (100%) in 28 patients (10 normal and 18 CAD), with a clinical diagnosis of unstable angina pectoris. Overall, the predictive accuracy of an abnormal scintigram with quantitative tomographic imaging (98%) was significantly better (p<0.05) than either qualitative planar or pinhole imaging. (JMT)

  9. Pulmonary uptake of sestamibi on early post-stress images: angiographic relationships, incidence and kinetics.

    PubMed

    Hurwitz, G A; Fox, S P; Driedger, A A; Willems, C; Powe, J E

    1993-01-01

    Early post-stress imaging with 99Tcm-sestamibi has the potential to reveal ancillary markers of severe coronary artery disease. Lung/myocardial ratios of sestamibi were assessed after pharmacologic, exercise or combined stress, and these were compared with historical controls who were stressed similarly, but imaged with 201Tl. Forty initial patients had planar imaging and correlating angiograms; pulmonary uptake for sestamibi related to severe coronary artery stenoses when measured on immediate images, started at 4 min post-stress (P = 0.04), but had a poor relationship to angiographic findings when measured on delayed clinical images. Of 180 subsequent studies, increased pulmonary uptake of sestamibi was seen more frequently (incidence = 34%) in those with abnormal tomograms compared to those with normal tomograms (incidence = 13%, P < 0.01), but appeared less frequently than on abnormal 201Tl studies (incidence = 60%). With sequential imaging for 5 min after injection, pulmonary uptake showed a greater fall with time on sestamibi studies than on matched 201Tl studies. No consistent differences were seen among the stress modalities. As an ancillary sign of haemodynamically severe disease, increased pulmonary uptake can be seen after various stress modalities, but may be more difficult to apply with sestamibi than with thallium imaging.

  10. Output of radiopharmaceutical nuclides of known injected doses from a municipal sewage treatment system.

    PubMed

    Nakamura, Ayako; Hayabuchi, Naofumi; Osaki, Tomoe; Osaki, Susumu

    2005-02-01

    The concentrations of (99m)Tc, (123)I, (67)Ga, and (201)Tl of the discharge water and the sewage sludge from Kurume Central Sewage Treatment Plant were determined once a week for 2 mo. The radiopharmaceutical doses injected into the patients for all of four hospitals that use nuclear medicines in the service area of the plant were also surveyed. Approximately 1.5% of the (99m)Tc, 1.5% of the (123)I, 4.3% of the (67)Ga, and 0.41% of the (201)Tl of the injected doses were detected in the discharged water from the plant. The behavior of these radionuclides in the sewage treatment system was analyzed using a compartment model. The analyses suggest that the average residence times in storage tanks and drainage pipes before entering the plant were 9.5 h for (99m)Tc, 81 h for (123)I, 120 h for (67)Ga, and 480 h for (201)Tl.

  11. Improvement of cardiac function and neurological remodeling in a patient with tachycardia-induced cardiomyopathy after catheter ablation.

    PubMed

    Omichi, Chikaya; Tanaka, Takeshi; Kakizawa, Yoshiko; Yamada, Ayako; Ishii, Yasuhiro; Nagashima, Hirotaka; Kanmatsuse, Katsuo; Endo, Masahiro

    2009-08-01

    Incessant ventricular tachycardia and long-standing ectopic beats lead to tachycardia-induced cardiomyopathy. Catheter ablation eliminates ventricular tachycardia and reverses left ventricular (LV) dysfunction. 201-Thallium ((201)Tl) scintigraphy demonstrates perfusion defects with ischemic cardiomyopathy. Reversible perfusion defects are observed even in non-ischemic cardiomyopathy, related to regional flow or metabolism derangements. 123-I-metaiodobezylguanidine ((123)I-MIBG) scintigraphy delineates regional cardiac sympathetic denervation and heterogeneity. We demonstrated the progression of tachycardia-induced cardiomyopathy in a patient with idiopathic LV outflow tract tachycardia using (201)Tl and (123)I-MIBG scintigraphic findings. Regional defects were reversed predominantly in the basal interventricular septal wall in (201)Tl scintigraphy and (123)I-MIBG scintigraphic findings. This report suggests that incessant ventricular tachycardia or long-standing ventricular ectopic beats may develop adverse myocardial remodeling and sympathetic neurological remodeling. Treatment with catheter ablation for tachycardia-induced cardiomyopathy can reverse sympathetic neurological remodeling as well as myocardial structural remodeling.

  12. Thallium-201 SPECT increases detectability of thyroid cancer metastases

    SciTech Connect

    Charkes, N.D.; Vitti, R.A.; Brooks, K. )

    1990-02-01

    Thallium-201- ({sup 201}Tl) chloride is known to accumulate in metastatic foci of differentiated thyroid carcinoma, but small and deep-seated lesions are generally not detectable by planar imaging. We have evaluated the use of 201Tl-chloride single-photon emission computed tomography (SPECT) in 41 post-thyroidectomy patients with differentiated thyroid carcinoma and one with medullary carcinoma; planar imaging alone was done in eight additional patients (total 50). Of 20 patients with known metastatic disease, planar {sup 201}Tl images were positive in 12 (60%) but SPECT revealed an additional 5 (25%) who had metastases (total 85%). SPECT revealed foci as small as 1.0 cm in the neck and 1.5 cm in the lungs, and was particularly useful in detection of disseminated micronodular pulmonary metastases, especially in patients whose scans were negative with diagnostic doses of {sup 131}I. Some pitfalls in interpretation of the tomographic reconstructions were found. Thallium-201 SPECT is a marked improvement over planar imaging in the detection of metastases of differentiated thyroid cancer.

  13. Segmental quantitative analysis of digital thallium-201 myocardial scintigrams in diagnosis of coronary artery disease. Comparison with rest and exercise electrocardiography and coronary arteriography.

    PubMed Central

    Wainwrwight, R J; Maisey, M N; Sowton, E

    1981-01-01

    One hundred and forty-nine patients with suspected ischaemic heart disease were evaluated by exercise thallium-201 myocardial scintigraphy (201Tl SMS), single lead exercise electrocardiography, and coronary arteriography. Myocardial distribution of tracer was assessed semi-quantitatively from digital 201Tl scintigrams and compared with tracer distribution in subjects with normal hearts. Fifty-two of 54 (96%) patients with normal coronary arteries had normal myocardial scintigrams whereas three patients had a positive ischaemic exercise electrocardiogram and were scan normal. Conversely, 36 of 95 (38%) patients with coronary artery disease had a positive ischaemic electrocardiogram compared with 94 of 95 (99%) patients who had a positive myocardial scintigram. Disease in specific coronary arteries could be deduced from the topography of myocardial tracer deficit. Disease was predicted correctly in 76 out of 80 (95%) of left anterior descending coronary stenoses, in 48 out of 64 (75%) of right coronary artery stenoses, and in 55 out of 64 (85%) of left circumflex coronary artery stenosis, despite the presence of infarcted myocardium in other territories. Similarly, single vessel disease was predicted correctly in 14 out of 17 (82%) patients and multiple vessel disease in 64 out of 77 (83%) patients. 201Tl SMS with segmental quantitative analysis is a highly sensitive and specific technique in the diagnosis of coronary artery disease and may be useful screening procedure to select patients for further investigation, particularly those with evidence of life-threatening severe left coronary artery disease. PMID:7317214

  14. Exercise thallium-201 myocardial scintigraphy in the follow-up of aortocoronary bypass graft surgery.

    PubMed Central

    Wainwright, R J; Brennand-Roper, D A; Maisey, M N; Sowton, E

    1980-01-01

    The predictive accuracy of exercise thallium-201 (201Tl) myocardial scintigraphy in the evaluation of aortocoronary bypass graft surgery was assessed in 48 patients undergoing angiographic investigation 15 months (mean time) after myocardial revascularisation. 201Tl scintigrams detected 61 out of 77 (79%) patent grafts but only 21 out of 42 (50%) occluded grafts, though, for grafts supplying non-infarcted myocardium, the predictive accuracy of graft patency and graft occlusion was 85 per cent and 81 per cent, respectively. Stress electrocardiography failed to detect 15 out of 21 patients with scintigraphic evidence of regional myocardial ischaemia. Residual ischaemia in the proximal left anterior descending coronary distribution was commonly detected in 201Tl scintigrams despite a patent, well-functioning left anterior descending graft to the distal coronary segment. Additional residual ischaemia attributable to ungrafted coronary disease was detected by scintigraphy in 32 (67%) patients and most commonly occurred in the distribution of the diagonal branch of the left anterior descending especially in the presence of a patent distal left anterior descending graft. Thus, independent grafts to the diagonal branch of the left anterior descending are recommended at the time of aortocoronary bypass graft surgery. Images PMID:6965585

  15. Evaluation of thallium-201 production in INER's compact cyclotron based on excitation functions

    NASA Astrophysics Data System (ADS)

    Sheu, R. J.; Jiang, S. H.; Duh, T. S.

    2003-12-01

    The production of Thallium-201 via the 203Tl(p,3n) 201Pb→ 201Tl process in the compact cyclotron TR30/15 of the Institute of Nuclear Energy Research (INER) was evaluated based on excitation functions. This study involves a selection of a series of parameters including proton energy, target thickness, and irradiation time that will maximize the yield of the product and minimize the radioactive impurities. The excitation functions of the 203Tl(p, xn)Pb reactions have been calculated by using the ALICE-91 and FLUKA codes, respectively. Their results were compared with that recommended in the IAEA-TECDOC-1211 report. The discrepancies among them were identified and the resulting effects on the integral yields were discussed. Based on the recommended nuclear data, a user-friendly program has been developed to estimate the activities of the product and impurities during the production process of 201Tl in INER's compact cyclotron (INERCC). This helps in understanding the effects of various parameters selected in the production process. The results reveal that the current status of the production process of 201Tl in INERCC appears to be quite optimal and the production yield is close to its theoretical prediction.

  16. Assessment of myocardial viability in patients with myocardial infarction using twenty-four hour thallium-201 late redistribution imaging.

    PubMed

    Yang, Xiang-Jun; He, Yong-Ming; Zhang, Bin; Wu, Yi-Wei; Hui, Jie; Jiang, Ting-Bo; Song, Jian-Ping; Liu, Zhi-Hua; Jiang, Wen-Ping

    2006-01-01

    Rest thallium-201 (201Tl) myocardial perfusion imaging has been widely used for evaluation of myocardial ischemia/viability after myocardial infarction, but the ideal timing for imaging after injection to maximally estimate viability is not well established. Thirty-six patients with myocardial infarction underwent the initial, 3 h, and 24 h redistribution imaging after intravenous injection of 148-185 MBq 201Tl. The initial and 3 h images, the initial and 24 h images, and the 3 and 24 h images were compared double-blinded. Out of the 184 abnormal segments based on the initial imaging, 56 (30%) segments improved by at least 1 grade on the 3 h imaging while 78 (42%) segments improved by at least 1 grade on the 24 h imaging. The 24 h late imaging detected more viable myocardium than the 3 h imaging did, with a significant difference (chi2= 5.680, p = 0.017). There were 158 abnormal segments on the 3 h imaging, with average 28% (44) segments improved by at least 1 grade on the 24 h imaging. There were 128 initial abnormal segments with no improvement on the 3 h imaging. Out of these segments, the 24 h late redistribution imaging detected additional redistribution in 26 segments, taking up 20%. Twenty-four hour late 201Tl imaging will demonstrated additional redistribution in patients who have incompletely reversible defects on early redistribution imaging at 3h.

  17. Comparison of myocardial imaging with iodine-123-iodophenyl-9-methyl pentadecanoic acid and thallium-201-chloride for assessment of patients with exercise-induced myocardial ischemia

    SciTech Connect

    Chouraqui, P.; Maddahi, J.; Henkin, R.; Karesh, S.M.; Galie, E.; Berman, D.S. )

    1991-03-01

    Iodine-123-iodophenyl-9-methyl-pentadecanoic acid (({sup 123}I)MPDA) and thallium-201 ({sup 201}Tl) were sequentially injected in 11 patients during exercise-induced myocardial ischemia. Simultaneous dual-energy planar images were obtained at 5 min, 3 and 5 hr. All studies were concordantly either positive (8/11) or negative (3/11) by both radionuclides. Exact agreement for segmental uptake was 93%, 94% and 94% for 5-min, 3- and 5-hr images, respectively. Exact agreement for defect reversibility by 3 and 5 hr were 95% and 92%. The initial defect contrasts and myocardial-to-lung ratios were similar by both agents but myocardial-to-liver ratio was lower by ({sup 123}I)MPDA at 5 min, which became similar to {sup 201}Tl at 5 hr. Normal percent myocardial clearances of both agents were comparable and significantly higher than those in defect zones. Thus ({sup 123}I)MPDA is suitable for myocardial imaging and correlates closely with {sup 201}Tl for initial postexercise myocardial uptake and defect reversibility. Defect reversibility appears to result from differential myocardial clearance from normal and ischemic regions.

  18. Thallium-201 scintigraphy is an effective diagnostic modality to distinguish malignant from benign soft-tissue tumors.

    PubMed

    Kawakami, Naoaki; Kunisada, Toshiyuki; Sato, Shuhei; Morimoto, Yuki; Tanaka, Masato; Sasaki, Tsuyoshi; Sugihara, Shinsuke; Yanai, Hiroyuki; Kanazawa, Susumu; Ozaki, Toshifumi

    2011-11-01

    The aim of this study is to evaluate whether thallium-201 (201-Tl) scintigraphy can differentiate malignant from benign soft-tissue tumors. Between April 1995 and December 2005, 192 patients with soft-tissue tumors (85 malignant and 107 benign) underwent 201-Tl scintigraphy before treatment. Isotope uptake was used as a proxy for tumor-to-background ratio (TBR). The accuracy of TBR on early and delayed imaging was evaluated using the Mann-Whitney U and χ(2) tests. There was a statistically significant difference in mean TBR on early and delayed imaging of malignant and benign soft-tissue tumors (124% ± 109% vs. 22% ± 42%, and 82% ± 83% vs. 12% ± 25%, P < 0.0001). A TBR cutoff of 20% indicated the probability of malignancy on early and delayed imaging (82% sensitivity and 77% specificity; 82% sensitivity and 84% specificity, P < 0.0001). Well-differentiated liposarcomas showed low isotope accumulation, while pigmented villonodular synovitis and giant cell tumors of the tendon sheath showed high isotope accumulation. Thallium-201 scintigraphy can distinguish malignant from benign tumors with relatively high accuracy. With the exception of low grade liposarcomas and locally aggressive benign tumors, 201-Tl scintigraphy may be an effective diagnostic modality to differentiate malignant from benign soft-tissue tumors.

  19. Estimation of infarct size by myocardial emission computed tomography with thallium-201 and its relation to creatine kinase-MB release after myocardial infarction in man

    SciTech Connect

    Tamaki, S.; Nakajima, H.; Murakami, T.

    1982-11-01

    Emission computed tomography (ECT) for thallium-201 (/sup 201/Tl) myocardial imaging was evaluated in estimating infarct size (IS). In 18 patients in whom IS was estimated enzymatically at the time of the acute episode, planar /sup 201/Tl perfusion scintigraphy and ECT with a rotating gamma camera were performed 4 weeks after the first myocardial infarction. From the size of /sup 201/Tl perfusion defects, the infarct area in planar images and the infarct volume in reconsturcted ECT images were measured by computerized planimetry. When scintigraphic IS was compared with the accumulated creatine kinase-MB isoenzyme release (CK-MBr), infarct volume determined from ECT correlated closely with CK-MBr (r=0.89), whereas infarct area measured from planar images correlated less satisfactorily with the enzymatic IS (for an average infarct area from three views, r=0.69; for the largest infarct area, r=0.73). Although conventional scintigraphic evaluation is useful for detecting and localizing infarction, quantification of ischemic injury with this two-dimensional technique has a significant inherent limitation. The ECT approach can provide a more accurate three-dimensional quantitative estimate of infarction, and can corroborate the enzymatic estimate of IS.

  20. Clinical evaluation of 360 degrees and 180 degrees data sampling techniques for transaxial SPECT thallium-201 myocardial perfusion imaging.

    PubMed

    Go, R T; MacIntyre, W J; Houser, T S; Pantoja, M; O'Donnell, J K; Feiglin, D H; Sufka, B J; Underwood, D A; Meaney, T F

    1985-07-01

    The most serious controversy regarding the application of transaxial SPECT technology to 201Tl myocardial perfusion imaging is the choice between 360 degrees compared with 180 degrees data sampling techniques. The present study utilized the original 360 degrees sampled raw data of 25 patients who had both SPECT 201Tl myocardial perfusion imaging and coronary angio/ventriculography for back projection reprocessing to accomplish the 360 degrees/180 degrees comparison. The results show a high incidence, 36% (9/25), of false-positive segmental perfusion abnormality and a high incidence, 24% (6/25), of moderate to severe degree of image distortion with the 180 degrees data sampled reconstructed images. These were not observed in the 360 degrees data sampled reconstructed images. The above findings confirmed our previous preliminary conclusion that even though the 180 degrees data sampling technique has the advantage of providing improved image contrast and reduction in acquisition time it is not a reliable technique and should be abandoned. The 360 degrees data sampling is the technique of choice for transaxial SPECT 201Tl myocardial perfusion imaging.

  1. Imaging of cocaine-induced global and regional myocardial ischemia

    SciTech Connect

    Oster, Z.H.; Som, P.; Wang, G.J.; Weber, D.A. )

    1991-08-01

    Severe and often fatal cardiac complications have been reported in cocaine users with narrowed coronary arteries caused by atherosclerosis as well as in young adults with normal coronaries. The authors have found that in normal dogs cocaine induces severe temporary hypoperfusion of the left ventricle as indicated by a significantly lower 201Tl concentration compared to the baseline state. The most significant decrease in uptake occurred 5 min after injection and was more pronounced in the septal and apical segments. Following intravenous administration of cocaine, instead of gradual disappearance of 201Tl from the left ventricle, there was continuous increase in 201Tl concentration in the left ventricle. These imaging experiments indicate that the deleterious effects of cocaine on the heart are probably due to spasm of the coronaries and decreased myocardial perfusion. Since spasm of the large subpericardial vessels does not seem to explain the magnitude of the increased coronary resistance and decreased coronary flow after cocaine as described in the literature, it is suggested that microvascular spasm of smaller vessels plays a major role in the temporary decrease in perfusion. The data may also suggest that severe temporary myocardial ischemia is probably the initiating factor for the cardiac complications induced by cocaine.

  2. Determinação de elementos próprios dos asteróides troianos: comparação entre as teorias semi-analítica e sintética

    NASA Astrophysics Data System (ADS)

    Roig, F.; Beaugé, C.

    2003-08-01

    Além do cálculo semi-analítico de elementos próprios dos asteróides Troianos (Beaugé & Roig 2001, Icarus 153, 391), recentemente foi apresentado um novo conjunto destes elementos próprios determinado através de uma teoria sintética (Knenezevic & Milani 2003, comunicação pessoal). As bases de dados contendo estas determinações estão disponiveis na pagina web do Asteroid Dynamical Site (http://hamilton.dm.unipi.it/cgi-bin/astdys/astibo). Nesta comunicação apresentamos os primeiros resultados de um estudo comparativo entre ambos conjuntos de elementos próprios, analisando suas vantagens e desvantagens, assim como os limites de precisão de cada conjunto. Mostramos que os elementos próprios sintéticos são mais precisos que os smi-analíticos para grandes amplitudes de libração do ângulo s = l-lJup, embora acontece o contrario para os corpos cuja amplitude de libração é muito pequena. Finalmente discutimos a influencia destes erros na determinação de familias de asteroides e da estrutura resonante em torno dos pontos Lagrangeanos L4 e L5.

  3. Thallium-201 SPECT in prognostic assessment of malignant gliomas treated with postoperative radiotherapy.

    PubMed

    Semba, Takatoshi; Sugawara, Yoshifumi; Ochi, Takashi; Fujii, Takashi; Mochizuki, Teruhito; Ohnishi, Takanori

    2006-05-01

    This study was designed to investigate the value of preoperative thallium-201 (201Tl) SPECT as a predictor of outcome in malignant glioma. From January 1990 to September 2003, 109 patients with glioma were treated with postoperative radiotherapy. Of these, 36 patients with malignant gliomas who underwent preoperative 201Tl-SPECT were included in this study (grade 3: n=14, grade 4: n=22). On early (10 minutes) and delayed (2 hours) images after 111 MBq 201TlCl injection, we calculated radioactivity ratios of tumors to contralateral normal brain (T/N ratios) and retention indices (RIs). For early and delayed images, we compared outcome between a high T/N ratio group (T/N ratio equal or greater than the average) and a low T/N ratio group (T/N ratio less than the average). We also divided the patients into two groups on the basis of RI; a high RI group (RI equal or greater than the average) and a low RI group (RI less than the average), and similarly compared outcome between the two groups. Median survival time was 12 months for both grade 3 and grade 4 tumors; however, two-year survival was 53% for grade 3 and 15% for grade 4. In both early and delayed images, outcome was significantly better for patients with low T/N ratios (early < 4.71, delayed < 3.96) than those with high T/N ratios (early: p = 0.030, delayed: p = 0.049). However, no significant survival difference was apparent between the low- (< -12.25) and high RI groups. In grade 3 glioma, patients with high T/N ratios demonstrated a tendency toward poorer outcome, although this trend was not significant (early: p = 0.079, delayed: p = 0.099). Overall outcome was poor for grade 4 glioma, and the difference in survival between low and high T/N ratio groups was not significant (early: p = 0.51, delayed: p = 0.53). However, long survival was seen only in patients with lower T/N ratios. Differences of 201Tl uptake in malignant gliomas could predict outcome. 201Tl-SPECT is potentially useful in the management of

  4. Factores socio-económicos asociados a la percepción de situación socioeconómica entre adultos mayores de dos países latinoamericanos

    PubMed Central

    Brenes-Camacho, Gilbert

    2014-01-01

    El objetivo principal del artículo es estudiar la asociación entre la percepción subjetiva sobre la situación económica propia y una serie de medidas objetivas de bienestar socioeconómico –fuentes de ingresos, tenencia de vivienda, nivel educativo y transferencias familiares informales de dinero- entre adultos mayores de dos países Latinoamericanos: México y Costa Rica. Los datos se obtienen de las primeras rondas de dos encuestas sobre envejecimiento: CRELES para Costa Rica y ENASEM para México. La variable dependiente más importante se obtiene de las respuestas a las pregunta “¿Cómo califica su situación económica actual?” en Costa Rica y “¿Diría usted que su situación económica es…?” en México. Para ambas encuestas, las respuestas se codificaron en forma binaria; el código 0 representa las categorías Excelente, Muy buena y Buena, y el código 1 representa a las categorías Regular y Mala. Se encontró que el ingreso por jubilación es un importante determinante de la percepción de bienestar en ambos países. En Costa Rica, el ingreso del cónyuge y la tenencia de vivienda son importantes predictores de la percepción de bienestar, mientras que en México, los ingresos por transferencias están fuertemente asociados con dicha percepción. PMID:25360057

  5. Identificabilidade e estabilidade dos parâmetros no método Grade of Membership (GoM): considerações metodológicas e práticas

    PubMed Central

    Guedes, Gilvan Ramalho; Caetano, André Junqueira; Machado, Carla Jorge; Brondízio, Eduardo Sonewend

    2011-01-01

    O método Grade of Membership (GoM) tem sido cada vez mais utilizado por demógrafos brasileiros e tem a vantagem de possuir um parâmetro que mensura a heterogeneidade individual, com base nas correlações não-observáveis entre as categorias de resposta das variáveis de interesse, gerando um medida do grau de pertencimento de cada indivíduo a perfis extremos. Alguns autores, contudo, chamam atenção para questões importantes na calibragem dos modelos finais que utilizam o programa GoM versão 3.4, como o problema de identificabilidade – soluções múltiplas para parâmetros estimados. Neste artigo, é sugerido um procedimento capaz de identificar um modelo final com solução única que descreva os tipos puros mais fidedignos à base de dados, em uma tentativa de otimização. Para ilustrar esse processo, utilizou-se uma base de dados correspondente a um levantamento econômico e sociodemográfico de uma população de pequenos agricultores residentes ao longo da Rodovia Transamazônica, no Estado do Pará. Também identificou-se a existência de instabilidade nos parâmetros estimados pelo programa GoM 3.4, sendo proposto um método de estabilização de seus valores. Com esses procedimentos combinados, os usuários do programa GoM 3.4 poderão descrever sua base de dados de forma mais adequada e responder às críticas sobre questões de identificabilidade e estabilidade dos modelos resultantes. Essas soluções empíricas são relevantes por afetarem cálculos de prevalência e de incidência de eventos de interesse, além de trazerem consequências importantes sobre o ponto e o momento corretos para intervenções de políticas públicas ou de planejamento prospectivo em análises de projeção. PMID:21709732

  6. Tritium ((3)H) as a tracer for monitoring the dispersion of conservative radionuclides discharged by the Angra dos Reis nuclear power plants in the Piraquara de Fora Bay, Brazil.

    PubMed

    de Carvalho Gomes, Franciane; Godoy, José Marcus; de Carvalho, Zenildo Lara; de Souza, Elder Magalhães; Rodrigues Silva, José Ivan; Tadeu Lopes, Ricardo

    2014-10-01

    Presently, two nuclear power plants operate in Brazil. Both are located at Itaorna beach, Angra dos Reis, approximately 133 km from Rio de Janeiro city. The reactor cooling circuits require the input of seawater, which is later discharged through a pipeline into the adjacent Piraquara de Fora Cove. The radioactive effluents undergo ion-exchange treatment prior to their release in batches, causing the enrichment of (3)H relative to other radionuclides in the discharged waters. Under steady state conditions, the (3)H gradient in the Piraquara de Fora waters can be used to determine the dependence of the dilution factor on the distance from the discharge point. The present work describes experiments carried out at the reactor site during batch release episodes, including time series sampling at the discharge point and surface seawater sampling every 250 m to a distance of 1250 m, after a double distillation, the (3)H concentration was measured by liquid scintillation counting applying a Quantulus liquid scintillation spectrometer. The obtained results showed a linear relationship between the (3)H concentration and distance from the discharge point. At 1250 m from the discharge point a dilution index of 1:15 was measured which fits the expected value based on modeling.

  7. Automatic scaling of critical frequency foF2 from ionograms recorded at São José dos Campos, Brazil: a comparison between Autoscala and UDIDA tools

    NASA Astrophysics Data System (ADS)

    Pezzopane, Michael; Pillat, Valdir Gil; Fagundes, Paulo Roberto

    2017-02-01

    This paper considers a dataset of ionograms recorded by the CADI ionosonde installed at São José dos Campos (SJC; 23.2°S, 45.9°W, magnetic latitude 14.1°S), Brazil, to compare two autoscaling systems: Autoscala, developed by the Istituto Nazionale di Geofisica e Vulcanologia, and the UDIDA-scaling, developed by the Universidade do Vale do Paraíba. The analysis, focused on the critical frequency of the F2 layer, foF2, shows that the two systems work differently. The UDIDA-scaling gives always a value of foF2 as output, regardless of the presence of the ionogram trace and its definition, while Autoscala tends to reject ionograms for which the digital information is considered insufficient. As a consequence, the UDIDA-scaling can autoscale more foF2 values than Autoscala, but Autoscala can discard a larger number of ionograms for which the trace is unidentifiable. Discussions are made on the accuracy of the foF2 values given as output, as well as on the main shortcomings characterizing the two systems.

  8. Pepita Talks Twice = Pepita habla dos veces.

    ERIC Educational Resources Information Center

    Lachtman, Ofelia Dumas

    This illustrated bilingual children's book (English and Spanish), relates the story of Pepita, a young Hispanic girl who is fluent in both Spanish and English. Pepita always helps when asked to talk for others in Spanish and English. But one day Pepita decides she doesn't want to help anymore. She wants to hurry and get home from school before her…

  9. 27 CFR 9.175 - Dos Rios.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... contour line and Poonkinny Road, proceed southerly and then easterly along the meandering 2,000-foot contour line to its intersection with the eastern boundary of section 2, T21N, R13W, immediately south of... then westerly along the meandering 2,000-foot contour line, crossing Big Water Canyon, Doghouse...

  10. 27 CFR 9.175 - Dos Rios.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... contour line and Poonkinny Road, proceed southerly and then easterly along the meandering 2,000-foot contour line to its intersection with the eastern boundary of section 2, T21N, R13W, immediately south of... then westerly along the meandering 2,000-foot contour line, crossing Big Water Canyon, Doghouse...

  11. 27 CFR 9.175 - Dos Rios.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... contour line and Poonkinny Road, proceed southerly and then easterly along the meandering 2,000-foot contour line to its intersection with the eastern boundary of section 2, T21N, R13W, immediately south of... then westerly along the meandering 2,000-foot contour line, crossing Big Water Canyon, Doghouse...

  12. 27 CFR 9.175 - Dos Rios.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... contour line and Poonkinny Road, proceed southerly and then easterly along the meandering 2,000-foot contour line to its intersection with the eastern boundary of section 2, T21N, R13W, immediately south of... then westerly along the meandering 2,000-foot contour line, crossing Big Water Canyon, Doghouse...

  13. DOS/Russian - US program overview

    SciTech Connect

    Pifer, M.L.

    1996-04-01

    This paper describes the organization and describes the objectives for the science and technology agreements between the U.S.A. and Russia. The Gore-Chernomyrdin Commission objectives and the Civilian Research and the Development Foundation for the Independent States of the former Soviet Union (CRDF) are discussed.

  14. DOS Design/Application Tools. Volume 1

    DTIC Science & Technology

    1990-09-01

    a distributed program must be partitioned into a number of program units (objects and clients ) and subsequently allocated to the various processors...initiates the appropriate processes (objects and clients ) on the designated nodes. Payoff for Developers Performance: The allocation tool directly addresses...the relationship between a particular Unit of Distribution and the Processor to which it has been assigned for execution. Finally, note that Client (a

  15. Pepita Talks Twice = Pepita habla dos veces.

    ERIC Educational Resources Information Center

    Lachtman, Ofelia Dumas

    This illustrated bilingual children's book (English and Spanish), relates the story of Pepita, a young Hispanic girl who is fluent in both Spanish and English. Pepita always helps when asked to talk for others in Spanish and English. But one day Pepita decides she doesn't want to help anymore. She wants to hurry and get home from school before her…

  16. DIGLIB. PC-DOS Graphics Subroutine Library

    SciTech Connect

    Brand, H.R.

    1989-02-01

    DIGLIB is a collection of general graphics subroutines. It was designed to be small, reasonably fast, and device-independent. The software is readily usable by casual programmers for two-dimensional plotting.

  17. Molecular Characterization of Human Pathogenic Bunyaviruses of the Nyando and Bwamba/Pongola Virus Groups Leads to the Genetic Identification of Mojuí dos Campos and Kaeng Khoi Virus

    PubMed Central

    Groseth, Allison; Mampilli, Veena; Weisend, Carla; Dahlstrom, Eric; Porcella, Stephen F.; Russell, Brandy J.; Tesh, Robert B.; Ebihara, Hideki

    2014-01-01

    Background Human infection with Bwamba virus (BWAV) and the closely related Pongola virus (PGAV), as well as Nyando virus (NDV), are important causes of febrile illness in Africa. However, despite seroprevalence studies that indicate high rates of infection in many countries, these viruses remain relatively unknown and unstudied. In addition, a number of unclassified bunyaviruses have been isolated over the years often with uncertain relationships to human disease. Methodology/Principal Findings In order to better understand the genetic and evolutionary relationships among orthobunyaviruses associated with human disease, we have sequenced the complete genomes for all 3 segments of multiple strains of BWAV (n = 2), PGAV (n = 2) and NDV (n = 4), as well as the previously unclassified Mojuí dos Campos (MDCV) and Kaeng Khoi viruses (KKV). Based on phylogenetic analysis, we show that these viruses populate 2 distinct branches, one made up of BWAV and PGAV and the other composed of NDV, MDCV and KKV. Interestingly, the NDV strains analyzed form two distinct clades which differed by >10% on the amino acid level across all protein products. In addition, the assignment of two bat-associated bunyaviruses into the NDV group, which is clearly associated with mosquito-borne infection, led us to analyze the ability of these different viruses to grow in bat (RE05 and Tb 1 Lu) and mosquito (C6/36) cell lines, and indeed all the viruses tested were capable of efficient growth in these cell types. Conclusions/Significance On the basis of our analyses, it is proposed to reclassify the NDV strains ERET147 and YM176-66 as a new virus species. Further, our analysis definitively identifies the previously unclassified bunyaviruses MDCV and KKV as distinct species within the NDV group and suggests that these viruses may have a broader host range than is currently appreciated. PMID:25188437

  18. Impact of natural climate change and historical land use on vegetation cover and geomorphological process dynamics in the Serra dos Órgãos mountain range in Rio de Janeiro State, Brazil

    NASA Astrophysics Data System (ADS)

    Nehren, U.; Sattler, D.; Heinrich, J.

    2010-03-01

    The Serra dos Órgãos mountain range in the hinterland of Rio de Janeiro contains extensive remnants of the Atlantic Forest (Mata Atlântica) biome, which once covered about 1.5 million km² from Northeast to South Brazil and further inland to Paraguay and Argentina. As a result of historical deforestation and recent land use intensification processes today only 5 to 8% of the original Atlantic Forest remains. Despite the dramatic habitat loss and a high degree of forest fragmentation, the remnants are among the Earth’s most diverse habitats in terms of species richness. Furthermore, they are characterized by a high level of endemism. Therefore, the biome is considered a "hotspot of biodiversity". In the last years many efforts have been taken to investigate the Mata Atlântica biome in different spatial and time scales and from different scientific perspectives. We are working in the Atlantic Forest of Rio de Janeiro since 2004 and focus in our research particularly on Quaternary landscape evolution and landscape history. By means of landscape and soil archives we reconstruct changes in the landscape system, which are mainly the result of Quaternary climate variability, young tectonic uplift and human impact. The findings throw light on paleoecological conditions in the Late Quaternary and the impact of pre-colonial and colonial land use practices on these landscapes. In this context, a main focus is set on climate and human-driven changes of the vegetation cover and its consequences for the geomorphological process dynamics, in particular erosion and sedimentation processes. Research methods include geomorphological field studies, interpretation of satellite images, physical and chemical sediment and soil analyses as well as relative and absolute dating (Feo/Fed ratio and 14C dating). For the Late Quaternary landscape evolution, the findings are compared with results from paleoclimatic and paloecological investigations in Southeast and South Brazil using other

  19. ANÁLISE DA INSERÇÃO DOS TEMAS DE HUMANIDADES E ÉTICA, COM METODOLOGIA DE APRENDIZAGEM BASEADA EM PROBLEMAS, EM CURRICULO MÉDICO INTEGRADO EM ESCOLA PÚBLICA NO DISTRITO FEDERAL, BRASIL

    PubMed Central

    Novaes, Maria Rita Carvalho Garbi; Novaes, Luiz Carlos Garcez; Guilhem, Dirce; Lolas, Fernando; Silveira, Carla; Guiotti, Murilo

    2009-01-01

    Objetivo Realizar uma análise da inserção da ética e humanidades no currículo do Curso de Medicina da Escola Superior em Ciências da Saúde - ESCS, escola pública do Distrito Federal, Brasil, de forma a contribuir com o processo de gestão curricular. Metodologia O Estudo é de coorte e documental. Foram pesquisados 37 termos relacionados à ética e 36 referentes à humanização nos objetivos educacionais e conteúdo dos módulos temáticos, habilidades e atitudes e interação ensino-serviço-comunidade, de 1a a 4a série e no programa do internato no currículo (ano 2006) e no projeto pedagógico do Curso de Medicina (2001). Resultados Maior inserção da humanização, ética e bioética na 1a e 2a série, quando comparado à inserção na 3a e 4a série e no internato, (IC95%-α=0,034, pvalue=0,007). Unidade de habilidades e atitudes: freqüência das 3 temáticas no currículo da 1a a 4a séries (IC95%-α=0,026, pvalue=0,013). Quando comparada a inserção entre o internato e as quatro primeiras séries, observa-se que nestas a inserção da temática humanização é superior (IC95%-α=0,042, pvalue=0,029). Conclusão O currículo desenvolvido no ano de 2006 na ESCS apresentou correlação com o projeto pedagógico do curso e contemplou a temática de forma abrangente, em todas as séries e internato. PMID:20396594

  20. Prediction of coronary artery lesions in unstable angina by iodine 123 beta-methyl iodophenyl pentadecanoic acid (BMIPP), a fatty acid analogue, single photon emission computed tomography at rest.

    PubMed

    Morimoto, K; Tomoda, H; Yoshitake, M; Aoki, N; Handa, S; Suzuki, Y

    1999-08-01

    Iodine 123 beta-methyl iodophenyl pentadecanoic acid (123I-BMIPP), a beta-methyl-branched fatty acid analogue, has been proven by experimental studies to reveal abnormalities in fatty-acid-related metabolism. This study was undertaken to validate the accuracy and limitations of 123I-BMIPP imaging at rest in detecting myocardial metabolic abnormalities and predicting coronary lesions in unstable angina (UA). One hundred UA patients without prior myocardial infarction were studied. 123I-BMIPP and thallium 201 chloride (201TlCl) imaging with single photon emission computed tomography (SPECT) and coronary and left ventricular cineangiography (LVC) were performed 1 week after the last episode of angina. There was reduced uptake of 123I-BMIPP imaging in 70 patients, reduced uptake of 201TlCl in 41, and abnormal LVC contraction in 49 patients. There were significant increases in severity scores of 123I-BMIPP imaging along with increases in the number of stenosed coronary arteries and the severity of stenosis in individual coronary arteries. There was a significant reduction in 123I-BMIPP severity scores 1 month after percutaneous transluminal coronary angioplasty (p < 0.01) and a significant correlation between the severity scores of 123I-BMIPP and LVC (r=0. 579, p<0.001). Overall rates of sensitivity and specificity in detecting significant coronary stenosis by 123I-BMIPP imaging were 74% and 86%, respectively, whereas rates of sensitivity and specificity in detecting significant coronary stenosis by 201TlCl were 31% and 91%, respectively. 123I-BMIPP sensitivity increases to 86% if only advanced coronary stenosis of >90% is included. In conclusion, 123I-BMIPP myocardial imaging is an effective method of predicting coronary artery lesions of UA patients without provocative test.

  1. Sequential change of BMIPP uptake with age in spontaneously hypertensive rat model.

    PubMed

    Mochizuki, T; Tsukamoto, E; Ono, T; Itoh, K; Kanegae, K; Katoh, C; Shiga, T; Nakada, K; Kohya, T; Tamaki, N

    1997-11-01

    Changes in myocardial perfusion and metabolism are often associated with myocardial hypertrophy, but there are few reports describing the serial assessment of fatty acid metabolism in hypertrophic myocardium. The aim of this study is to assess fatty acid metabolism serially in hypertrophic myocardium in spontaneously hypertensive rats (SHR) with 125I-BMIPP, a branched fatty acid analog. SHR and Wistar-Kyoto rats (WKY) as the control were divided into 4 groups (12, 15, 18 and 51 weeks after birth). The heart was extracted 10 minutes after intravenous injection of 125I-BMIPP and 201Tl at the same time. The accumulation of each radiotracer in the myocardium was counted with a well gamma counter. In addition, 125I-BMIPP uptake was corrected by 201Tl uptake (B/T). The heart weight/body weight ratio was significantly higher in SHR than that in WKY (p < 0.001). In SHR, this ratio increased up to 18 weeks (12 weeks; 0.266 +/- 0.005, 18 weeks; 0.281 +/- 0.006: mean +/- SE, p < 0.05). The 125I-BMIPP uptake tended to be significantly reduced in SHR (12 weeks; 2.373 +/- 0.212, 18 weeks; 1.380 +/- 0.047; mean +/- SE, p < 0.05). Such a difference in BMIPP uptake was more evident when BMIPP uptake was corrected by Tl uptake (B/T), but no regional difference or heterogeneity of BMIPP distribution was observed in the hypertrophic myocardium in SHR. A change in fatty acid metabolism with age was observed in association with myocardial hypetrophy in this hypertensive rat model, which was well demonstrated with 125I-BMIPP and 201Tl.

  2. Effects of Different Containers on Radioactivity Measurements using a Dose Calibrator with Special Reference to (111)In and (123)I.

    PubMed

    Inoue, Yusuke; Abe, Yutaka; Kikuchi, Kei; Miyatake, Hiroki; Watanabe, Atsushi

    2017-01-01

    Low-energy characteristic x-rays emitted by (111)In and (123)I sources are easily absorbed by the containers of the sources, affecting radioactivity measurements using a dose calibrator. We examined the effects of different containers on the estimated activities. The radioactivities of (111)In, (123)I, (201)Tl, and (99m)Tc were measured in containers frequently employed in clinical practice in Japan. The (111)In measurements were performed in the vials A and B of the (111)In-pentetreotide preparation kit and in the plastic syringe. The activities of (123)I-metaiodobenzylguanidine and (201)Tl chloride were measured in the prefilled glass syringes and plastic syringes. The milking vial, vial A, vial B, and plastic syringe were used to assay (99m)Tc. For (111)In and (123)I, measurements were performed with and without a copper filter. The filter was inserted into the well of the dose calibrator to absorb low-energy x-rays. The relative estimate was defined as the ratio of the activity estimated with the dose calibrator to the standard activity. The estimated activities varied greatly depending on the container when (111)In and (123)I sources were assayed without the copper filter. The relative estimates of (111)In were 0.908, 1.072, and 1.373 in the vial A, vial B, and plastic syringe, respectively. The relative estimates of (123)I were 1.052 and 1.352 in the glass syringe and plastic syringe, respectively. Use of the copper filter eliminated the container-dependence in (111)In and (123)I measurements. Container-dependence was demonstrated in neither (201)Tl nor (99m)Tc measurements. The activities of (111)In and (123)I estimated with a dose calibrator differ greatly among the containers. Accurate estimation may be attained using the container-specific correction factor or using the copper filter.

  3. Physiological assessment of sensitivity of noninvasive testing for coronary artery disease

    SciTech Connect

    Simonetti, I.; Rezai, K.; Rossen, J.D.; Winniford, M.D.; Talman, C.L.; Hollenberg, M.; Kirchner, P.T.; Marcus, M.L. )

    1991-05-01

    The sensitivity of three noninvasive tests for coronary artery disease was assessed by means of quantitative indexes of disease severity in three different groups of patients. The overall population consisted of 110 subjects with limited coronary artery disease and no myocardial infarction. Planar dipyridamole-{sup 201}Tl scintigraphy was evaluated in 31 patients, computer-assisted exercise treadmill in 28, and high-dose dipyridamole echocardiography testing in 51. Sensitivity was assessed by rigorous gold standards to define disease severity, such as measurement of minimum cross-sectional area and percent area of stenosis, by quantitative computerized coronary angiography (Brown/Dodge method). On the basis of the results of previous studies, the presence of physiologically significant coronary artery disease was indicated by a stenotic minimum cross-sectional area (MCSA) of less than 2.0 mm{sup 2} or a greater than 75% area of stenosis. With MCSA as the gold standard, dipyridamole-{sup 201}Tl scintigraphy, computerized exercise treadmill, and dipyridamole echocardiography testing showed sensitivities of 52%, 54%, and 61%, respectively, in the three different patient cohorts enrolled. With percent area of stenosis as the gold standard, the sensitivity figures obtained for dipyridamole-{sup 201}Tl, computerized exercise treadmill, and dipyridamole echocardiography testing were 64%, 54%, and 69%, respectively. For each of the three tests, sensitivity increased with increasing lesion severity. Sensitivity was also better in patients with left anterior descending coronary (LAD) disease when compared with patients with left circumflex or right coronary artery disease. Results of these studies demonstrate that in patients with limited coronary artery disease none of the tests evaluated is definitely superior in sensitivity.

  4. Scintigraphic anatomy of coronary artery disease in digital thallium-201 myocardial images.

    PubMed Central

    Wainwright, R J

    1981-01-01

    One hundred and eight patients with single and multiple vessel coronary artery disease confirmed by arteriography were evaluated by exercise thallium-201 (201Tl) myocardial scintigraphy to determine the scintigraphic appearances of specific coronary stenoses. In general proximal stenoses caused more widespread, but not necessarily more severe, myocardial tracer deficit than distal stenoses. In particular, proximal dominant right coronary artery disease was specifically associated with extensive inferior wall tracer deficit in the anterior scintigram, whereas proximal left circumflex disease caused similar tracer depletion best visualised in the left lateral scintigram. A triad of uptake defects was caused by left anterior descending coronary artery disease: viz. apical tracer deficit (anterior view) in 71% lesions, septal tracer deficit (left anterior oblique view) in 83% of lesions, and anterolateral wall tracer deficit (left lateral projection) in 72% of lesions. The last defect has been termed a 'diagonal window' because it was associated with independent disease of the main diagonal branch of the left anterior descending coronary artery or with disease in the main left anterior descending artery situated proximal to this branch. Diagonal window tracer deficit was the most useful scintigraphic sign distinguishing proximal from distal disease in the left anterior descending coronary artery. False negative scintigraphic defects occurred more commonly in patients with triple vessel disease and in association with well-developed coronary collateral vessels. Certain scintigraphic patterns of 201Tl myocardial accumulation appear invaluable in the noninvasive localisation of stenoses within specific coronary arteries and thus may be useful in predicting life-threatening coronary artery disease which should be confirmed by definite coronary arteriography. The digital 201Tl myocardial scintigram also provides an independent functional guide to the interpretation of

  5. Quantitative (201)thallium scintigraphy for prediction of histological response to neoadjuvant chemotherapy in osteosarcoma; systematic review and meta-analysis.

    PubMed

    Kubo, Tadahiko; Shimose, Shoji; Fujimori, Jun; Furuta, Taisuke; Ochi, Mitsuo

    2015-09-01

    The histological assessment of tumor necrosis of the excised lesion after neoadjuvant chemotherapy is the most important prognostic factor for patients with osteosarcoma, but more early prognostic factors are needed for the adjustment of adjuvant treatment regimen. The objective of this systematic review is to provide an up-to-date and unprecedented summary of the value of (201)thallium ((201)Tl) scintigraphy for the preoperative evaluation of the chemotherapy response of osteosarcoma. Studies evaluating (201)Tl scintigraphy for the preoperative evaluation of the chemotherapy response of osteosarcoma were systematically searched for in MEDLINE, EMBASE, and Web of Science. Pooled sensitivity and specificity for each study were calculated into 2 × 2 contingency tables. The DerSimonian-Laird random-effects method was used for determining the pooled diagnostic odds ratio and the area under curve (AUC) of the summary receiver operating characteristic (SROC) curve. A total of six studies with 139 patients who fulfilled all of the inclusion criteria were considered for the meta-analysis. The pooled sensitivity and specificity were 0.93 (95% CI, 0.83-0.98) and 0.63 (95% CI, 0.52-0.74), respectively. A significant difference was found between the good and poor responders in the diagnostic odds ratio. The SROC curve showed that the AUC was 0.840, indicating excellent diagnostic accuracy. There was no statistically significant heterogeneity among the six studies. The alteration ratio derived from (201)Tl scintigraphy was useful for evaluating the histological response of patients to neoadjuvant chemotherapy in osteosarcoma. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Impaired Coronary Flow Reserve Is the Most Important Marker of Viable Myocardium in the Myocardial Segment-Based Analysis of Dual-Isotope Gated Myocardial Perfusion Single-Photon Emission Computed Tomography

    PubMed Central

    Lee, Won Woo; So, Young; Kim, Ki-Bong

    2014-01-01

    Objective The aim of this study was to investigate the most robust predictor of myocardial viability among stress/rest reversibility (coronary flow reserve [CFR] impairment), 201Tl perfusion status at rest, 201Tl 24 hours redistribution and systolic wall thickening of 99mTc-methoxyisobutylisonitrile using a dual isotope gated myocardial perfusion single-photon emission computed tomography (SPECT) in patients with coronary artery disease (CAD) who were re-vascularized with a coronary artery bypass graft (CABG) surgery. Materials and Methods A total of 39 patients with CAD was enrolled (34 men and 5 women), aged between 36 and 72 years (mean 58 ± 8 standard in years) who underwent both pre- and 3 months post-CABG myocardial SPECT. We analyzed 17 myocardial segments per patient. Perfusion status and wall motion were semi-quantitatively evaluated using a 4-point grading system. Viable myocardium was defined as dysfunctional myocardium which showed wall motion improvement after CABG. Results The left ventricular ejection fraction (LVEF) significantly increased from 37.8 ± 9.0% to 45.5 ± 12.3% (p < 0.001) in 22 patients who had a pre-CABG LVEF lower than 50%. Among 590 myocardial segments in the re-vascularized area, 115 showed abnormal wall motion before CABG and 73.9% (85 of 115) had wall motion improvement after CABG. In the univariate analysis (n = 115 segments), stress/rest reversibility (p < 0.001) and 201Tl rest perfusion status (p = 0.024) were significant predictors of wall motion improvement. However, in multiple logistic regression analysis, stress/rest reversibility alone was a significant predictor for post-CABG wall motion improvement (p < 0.001). Conclusion Stress/rest reversibility (impaired CFR) during dual-isotope gated myocardial perfusion SPECT was the single most important predictor of wall motion improvement after CABG. PMID:24642696

  7. ¹⁸F-Fluorocholine PET/CT as a complementary tool in the follow-up of low-grade glioma: diagnostic accuracy and clinical utility.

    PubMed

    Gómez-Río, Manuel; Testart Dardel, Nathalie; Santiago Chinchilla, Alicia; Rodríguez-Fernández, Antonio; Olivares Granados, Gonzalo; Luque Caro, Raquel; Zurita Herrera, Mercedes; Chamorro Santos, Clara E; Lardelli-Claret, Pablo; Llamas-Elvira, José M

    2015-05-01

    The follow-up of treated low-grade glioma (LGG) requires the evaluation of subtle clinical changes and MRI results. When the result is inconclusive, additional procedures are required to assist decision-making, such as the use of advanced MRI (aMRI) sequences and nuclear medicine scans (SPECT and PET). The aim of this study was to determine whether incorporating (18)F-fluorocholine PET/CT in the follow-up protocol for treated LGG improves diagnostic accuracy and clinical utility. This was a prospective case-series study in patients with treated LGG during standard follow-up with indeterminate clinical and/or radiological findings of tumour activity. All patients underwent clinical evaluation, aMRI, (201)Tl-SPECT and (18)F-fluorocholine PET/CT. Images were interpreted by visual evaluation complemented with semiquantitative analysis. Between January 2012 and December 2013, 18 patients were included in this study. The final diagnosis was established by histology (five surgical specimens, one biopsy specimen) or by consensus of the Neuro-Oncology Group (11 patients) after a follow-up of >6 months (mean 14.9 ± 2.72 months). The global diagnostic accuracies were 90.9% for aMRI (38.8% inconclusive), 69.2 % for (201)Tl-SPECT (11.1% inconclusive), and 100% for (18)F-fluorocholine PET/CT. (201)Tl-SPECT led correctly to a change in the initial approach in 38.9% of patients but might have led to error in 27.8%. The use of (18)F-fluorocholine PET/CT alone rather than (201)Tl-SPECT led correctly to a change in the approach suggested by routine follow-up in 72.2% of patients and endorsed the approach in the remaining 27.8%. Our results support the need to complement structural MRI with aMRI and nuclear medicine procedures in selected patients. (18)F-Fluorocholine PET/CT can be useful in the individualized management of patients with treated LGG with uncertain clinical and/or radiological evidence of tumour activity.

  8. Early and delayed thallium 201 imaging. Diagnosis of patients with cold thyroid nodules

    SciTech Connect

    Bleichrodt, R.P.; Vermey, A.; Piers, D.A.; de Langen, Z.J.

    1987-12-01

    To investigate the utility of thallium 201 (Tl-201) thyroid scintigraphy for the detection of thyroid malignancies, early and delayed Tl-201 scintigraphy was done in 70 consecutive patients with a clinically solitary cold (Iodine 123 (I-123)) nodule. Early Tl-201 scintigraphy had a sensitivity of 100% and a specificity of 7% in predicting malignancy. With a combination of early and delayed Tl-201 scintigraphy, sensitivity ranged from 17 to 25% and specificity from 95 to 100%. Early and and delayed Tl-201 scintigraphy are only of limited value for the detection of thyroid cancer.

  9. Serial dual single-photon emission computed tomography of thallium-201 and iodine-123 beta-methyliodophenyl pentadecanoic acid scintigraphy can predict functional recovery of patients with coronary artery disease after coronary artery bypass graft surgery.

    PubMed

    Fujita, Kishu; Kasama, Shu; Kurabayashi, Masahiko

    2015-02-01

    A mismatch between thallium-201 ((201)Tl) and iodine-123 ((123)I)-beta-methyl iodophenyl pentadecanoic acid (BMIPP) dual single-photon emission computed tomography (SPECT) reflects a dysfunctional but viable myocardium, such as stunned or hibernating myocardium, in patients with coronary artery disease (CAD). However, the cardiac function does not always improve after revascularization. The present study aimed to determine whether serial (201)Tl and (123)I-BMIPP dual SPECT can predict improvements in cardiac function after coronary artery bypass graft surgery (CABG) in patients with CAD. The study included 98 patients with CAD requiring CABG and having a left ventricular ejection fraction (LVEF) less than 50%. The total defect score (TDS) was calculated from (201)Tl and (123)I-BMIPP dual-SPECT images acquired before and 3 weeks after CABG. The LVEF, left ventricular end-diastolic volume index, and end-systolic volume index were determined by means of contrast left ventriculography before and 6 months after CABG. After 6 months, LVEF improved by 5% or more in 62 patients (group A) but did not improve in the remaining 36 patients (group B). Baseline Tl-TDS was significantly lower (9.1±4.6 vs. 14.6±6.5, P<0.001), and the mismatch score (BMIPP-TDS-Tl-TDS) was significantly higher (6.9±4.2 vs. 4.2±3.9, P=0.002) in group A than in group B. The extent of change in BMIPP-TDS 3 weeks after CABG compared with that before (delta-BMIPP-TDS) was significantly greater in group A than in group B (-5.9±3.0 vs. 2.8±4.3, P<0.001). Stepwise multivariate analysis selected delta-BMIPP-TDS as a significant independent predictor of improvement in LVEF at 6 months after CABG (multivariate β-coefficient=-0.718, P<0.001). The degree of change in LVEF 6 months after CABG compared with that before significantly and negatively correlated with delta-BMIPP-TDS (r=-0.631, P<0.001). The delta-BMIPP-TDS evaluated by serial (201)Tl and (123)I-BMIPP dual SPECT can predict improvements in

  10. Radiochemical separation methods for preparation of biomedical cyclotron radionuclides

    NASA Astrophysics Data System (ADS)

    Zaitseva, N. G.; Dmitriev, S. N.

    1999-01-01

    A short review of the radiochemical methods for preparation of widely used or promising cyclotronproduced radionuclides for nuclear medicine and biomedical or environmental studies is given. The presented data include the current status of the production of some gamma-emitters (97Ru, 111In, 123I, 201Tl), generator-pairs (68Ge/68Ga, 82Sr/82Rb, 128Ba/128Cs, 178W/178Ta), radioisotopes for metabolism studies (26Al, 67Cu, 237Pu) and actinides tracers for environmental researches (235Np, 236Np, 236Pu). The conditions for preparation of high-purity isotopes have been investigated and procedures including target chemistry design were developed.

  11. Radioimmunoscintigraphy using iodine-131-anti-CEA monoclonal antibodies and thallium-201 scintigraphy in medullary thyroid carcinoma: A case report

    SciTech Connect

    Zanin, D.E.; van Dongen, A.; Hoefnagel, C.A.; Bruning, P.F. , Amsterdam )

    1990-11-01

    This case report demonstrates the use of thallium-201 ({sup 201}Tl) scans versus iodine-131- ({sup 131}l) anti-CEA F(ab')2 scans in a patient with high serum CEA levels due to metastases of medullary thyroid carcinoma in the suprarenal region and sacroiliacal region. Scintigraphy using monoclonal antibodies directed against CEA showed a higher tumor uptake (0.26% dose and 0.64% dose, respectively) than a thallium scan and is believed to be promising for future radiotherapeutic applications.

  12. Thallium-201 chloride scintigraphy in soft tissue tumors.

    PubMed

    Otsuka, Hideki; Terazawa, Kaori; Morita, Naomi; Otomi, Yoichi; Takao, Shoichiro; Iwamoto, Seiji; Osaki, Kyosuke; Harada, Masafumi; Nishitani, Hiromu

    2009-08-01

    We report the findings of Thallium-201 chloride ((201)TlCl) scintigraphy and consider how to use this technique to evaluate the character of soft tissue lesions. We enrolled 91 consecutive patients (45 males and 46 females, age range 8-91-years-old). Nineteen patients were malignant and 72 were benign. Patients were scanned 15 minutes (early phase) and 3 hours (delayed phase) after (201)TlCl injection. More intense uptake in the lesion compared to the normal side was considered as 'high', the same degree of uptake was considered 'iso', and decreased uptake was 'low'. The retention index (RI) was calculated in 9 patients in the malignant group and in 16 patients in the benign group. In malignant tumors, 15 of 19 patients showed high uptake in both the early and delayed phases. One malignant fibrous histiocytoma patient was high only in the delayed phase and 1 liposarcoma patient was high only in the early phase. Two liposarcoma patients showed an iso uptake in both phases. One of these patients was pathologically diagnosed as a myxoid type. In benign lesions, no lipoma showed increased uptake. All neurogenic tumors except for 2 demonstrated high uptake. All 3 ganglions of the lower extremities showed iso uptake. Most inflammatory diseases showed increased uptake. Clinically-considered benign patients consisted of tumorous lesions or inflammatory disease. Only 2 patients were considered 'low', and these were diagnosed as intramuscular hematoma and cyst. RI was variable in both malignant and benign lesions and no statistically significant difference was seen between malignant and benign lesions by t-test (p=0.72). A high (201)TlCl uptake lesion is more frequently seen in malignant tumors, but regardless of whether the tumor is benign or malignant, according to the histopathological variety, the (201)TlCl uptake pattern can not be the only indicator to differentiate malignant from benign tumors. We ultimately need to evaluate the nature of tumors by a combination of

  13. Discordance of exercise thallium testing with coronary arteriography in patients with atypical presentations

    SciTech Connect

    Bungo, M.W.; Leland, O.S. Jr.

    1983-01-01

    Eighty-one patients with diagnostically difficult clinical presentations suggesting coronary disease underwent symptom-limited maximal-exercise treadmill testing (ETT) and exercise radionuclide scanning with /sup 201/Tl. Results of these tests were in agreement in only 47 percent of the cases. Either exercise thallium or ETT was positive in 94 percent of patients with disease. Among a population with a disease prevalence of 67 percent, agreement between exercise thallium an ETT predicted disease in 92 percent of instances or excluded disease in 82 percent of instances. Frequent discordance between these two tests in 53 percent of the cases unfortunately limits this usefulness.

  14. Comparison of the activity measurements in nuclear medicine services in the Brazilian northeast region.

    PubMed

    de Farias Fragoso, Maria da Conceição; de Albuquerque, Antônio Morais; de Oliveira, Mércia L; de Lima, Fabiana Farias; Barreto, Flávio Chiappetta Paes; de Andrade Lima, Ricardo

    2013-12-01

    The Northeastern Regional Centre for Nuclear Sciences (CRCN-NE), National Nuclear Energy Commission, has organized for the first time in nuclear medicine services (NMSs) in the Brazilian northeast region a comparison of activity measurements for (99m)Tc, (131)I, (67)Ga, (201)Tl and (57)Co. This tool is widely utilized to evaluate not only the accuracy of radionuclide calibrators, but also the competence of NMSs to measure the activity of the radiopharmaceuticals and the performance of the personnel involved in these measurements. The comparison results showed that 90% of the results received from participants are within the ±10% limit established by the Brazilian Norm.

  15. Influence of acquisition orbit on phase analysis of gated single photon emission computed tomography myocardial perfusion imaging for assessment of left ventricular mechanical dyssynchrony.

    PubMed

    Misaka, Tomofumi; Hosono, Makoto; Kudo, Takashi; Ito, Takamichi; Syomura, Tsutomu; Uemura, Masanobu; Okajima, Kaoru

    2017-04-01

    The association between left ventricular (LV) dyssynchrony parameters, given by phase analysis of gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI), and acquisition orbits is unclear. The aim of this study was to assess the dependence of LV dyssynchrony parameters on acquisition orbits. Ninety-nine patients who underwent (201)Tl-gated SPECT MPI were categorized into minor hypoperfusion or major hypoperfusion groups. Forty-four patients who underwent (99m)Tc-tetrofosmin-gated SPECT MPI were categorized into minor hypoperfusion or major hypoperfusion groups. The major hypoperfusion group with (201)Tl was divided into inferior or non-inferior wall hypoperfusion subgroups, and anteroseptal or non-anteroseptal wall hypoperfusion subgroups. Gated SPECT MPI data over a 360° acquisition orbit (360° images) and a 180° acquisition orbit (180° images) were reconstructed, and histogram bandwidth (HBW) and phase standard deviation (PSD) were compared. Between 360° and 180° images with (201)Tl, there were significant differences in HBW and PSD both globally (HBW 34.8 ± 16.6 vs. 29.1 ± 10.2; PSD 8.8 ± 4.9 vs. 7.0 ± 2.3, p < 0.05 for both) and in the inferior wall (HBW 29.5 ± 15.5 vs. 23.3 ± 9.0; PSD 7.6 ± 4.6 vs. 5.6 ± 2.4, p < 0.001 for both) in the major hypoperfusion group, and also in the inferior wall in all subgroups of the major hypoperfusion group. In contrast, no segment had any significant differences in HBW or PSD between 360° and 180° images with (99m)Tc. Differences in acquisition orbit had a significant influence on HBW and PSD with (201)Tl-gated SPECT MPI in the inferior wall in patients with major hypoperfusion myocardium.

  16. Screening for pulmonary tuberculosis in Teresópolis, RJ, Brazil: the search for respiratory symptomatic patients in emergency service of "Hospital das Clínicas de Teresópolis Costantino Ottaviano, Fundação Educacional Serra dos Orgãos".

    PubMed

    Siqueira-Batista, Rodrigo; Gomes, Andréia Patrícia; Bisaglia, Joana B; Borlot, Paulo Estevão W; D'avila Junior, Heraldo X; Faria, Carolina Gonçalves P P de; Braga, Bernardo D; Bezerra, Tiago S; Cedrola, Juan Pedro V; Almeida, Guilherme C; Couto, Lílian S; Nacif, Marcelo; Crivano, Elvira

    2005-01-01

    The aim of the present study was to investigate the detection percentage of tuberculosis among patients that are respiratory symptomatic (TB suspects). In this work, we present the preliminary results of research carried out at "Hospital das Clínicas de Teresópolis Costantino Ottaviano da Fundacao Educacional Serra dos Orgãos (FESO)" from November 2003 to April 2004. Among the 40 respiratory symptomatic individuals identified and referred to the Tuberculosis Control Program in Teresópolis , two (5.0%) were characterized as smear-positive. These results confirm reports in the literature and underscore the need for and importance of this strategy.

  17. p-Tertbutylcalix[4]arene nanoemulsion: preparation, characterization and comparative evaluation of its decontamination efficacy against Technetium-99m, Iodine-131 and Thallium-201.

    PubMed

    Rana, Sudha; Sharma, Navneet; Ojha, Himanshu; Shivkumar, Hosakote Gurumalappa; Sultana, Sarwat; Sharma, Rakesh Kumar

    2014-05-01

    This study aimed to develop p-tertbutylcalix[4]arene o/w nanoemulsion for decontamination of radioisotopes from skin. Formulation was characterized using dynamic light scattering (DLS), transmission electron microscopy (TEM), multi-photon confocal microscopy techniques and in vitro dissolution studies. In vivo evaluation of nano-emulsion was done using nuclear medicine technique. Stability studies and dermal toxicity studies were also carried out. Comparative decontamination efficacy (DE) studies were performed on synthetic human tissue equivalent material and Sprague Dawley rat against three commonly used medical radioisotopes, i.e., Technetium-99m ((99m)Tc), Iodine-131 ((131)I) and Thallium-201 ((201)Tl). Decontamination was performed using cotton swabs soaked in nanoemulsion at different time intervals of contaminants exposure. Whole body imaging and static counts were recorded using gamma camera before and after each decontamination attempt data was analyzed using one way analysis of variance (ANOVA) and found to be statistically significant (p<0.05). DE of the nanoemulsion loaded with p-tertbutylcalix[4]arene was observed to be 88±5%, 90±3% and 89±3% for (99m)Tc, (131)I and (201)Tl respectively. Dermal toxicity studies revealed no significant differences between treated and control animals. Skin histopathology slides with and without API (Active pharmaceutical ingredients) also found to be comparable. p-Tertbutylcalix[4]arene loaded nanoemulsion shows great promise for skin decontamination against broad ranges of radiological contaminants besides being stable and safe.

  18. Effects of propranolol and nifedipine on exercise-induced attack in patients variant angina: assessment by exercise thallium-201 myocardial scintigraphy with quantitative rotational tomography

    SciTech Connect

    Kugiyama, K.; Yasue, H.; Horio, Y.; Morikami, Y.; Fujii, H.; Koga, Y.; Kojima, A.; Takahashi, M.

    1986-08-01

    To examine the effects of propranolol and nifedipine on exercise-induced attack in patients with variant angina, exercise /sup 201/Tl myocardial scintigraphy with quantitative analysis by emission-computed tomography was performed in 20 patients with variant angina after oral propranolol (80 mg), nifedipine (20 mg), and placebo. Exercise-induced attack occurred in 11 patients on placebo, in 14 on propranolol, and in none on nifedipine. The exercise duration was significantly shorter in those on propranolol (p less than .05), but significantly longer in patients on nifedipine (p less than .05) than in those on placebo. The peak rate-pressure product was significantly lower in patients on propranolol (p less than .01), but did not change in those on nifedipine, as compared with that in patients on placebo. The size of the perfusion defect as measured by /sup 201/Tl tomography was significantly greater in patients on propranolol (p less than .05), but significantly less in those on nifedipine (p less than .01) than in those on placebo. In conclusion, propranolol does not suppress but rather may aggravate exercise-induced attack in patients with variant angina, while nifedipine suppresses it. This unfavorable effect of propranolol on exercise-induced attack in patients with variant angina is likely to be due to a reduction of regional myocardial blood flow.

  19. Biokinetics of radiolabeled Iodophenylpentadecanoic acid (I-123-IPPA) and thallium-201 in a rabbit model of chronic myocardial infarction measured using a series of thermoluminescent dosimeters

    NASA Astrophysics Data System (ADS)

    Medich, David Christopher

    1997-09-01

    The biokinetics of Iodophenylpentadecanoic acid (123I-IPPA) during a chronic period of myocardial infarction were determined and compared to 201Tl. IPPA was assessed as a perfusion and metabolic tracer in the scintigraphic diagnosis of coronary artery disease. The myocardial clearance kinetics were measured by placing a series of thermoluminescent dosimeters (TLDs) on normal and infarcted tissue to measure the local myocardial activity content over time. The arterial blood pool activity was fit to a bi-exponential function for 201Tl and a tri-exponential function for 123I-IPPA to estimate the left ventricle contribution to TLD response. At equilibrium, the blood pool contribution was estimated experimentally to be less than 5% of the total TLD response. The method was unable to resolve the initial uptake of the imaging agent due in part to the 2 minute TLD response integration time and in part to the 30 second lag time for the first TLD placement. A noticeable disparity was observed between the tracer concentrations of IPPA in normal and ischemic tissue of approximately 2:1. The fitting parameters (representing the biokinetic eigenvalue rate constants) were related to the fundamental rate constants of a recycling biokinetic model. The myocardial IPPA content within normal tissue was elevated after approximately 130 minutes post injection. This phenomenon was observed in all but one (950215) of the IPPA TLD kinetics curves.

  20. Significance of repeated exercise testing with thallium-201 scanning in asymptomatic diabetic males

    SciTech Connect

    Rubler, S.; Fisher, V.J.

    1985-12-01

    This study was conducted with asymptomatic middle-aged male subjects with diabetes mellitus to detect latent cardiac disease using noninvasive techniques. One group of 38 diabetic males (mean age 50.5 +/- 10.2 years) and a group of 15 normal males (mean age 46.9 +/- 10.0 years) participated in the initial trial; 13 diabetic patients and 7 control subjects were restudied 1-2 years later. Maximal treadmill exercise with a Bruce protocol and myocardial scintigraphy with thallium-201(201Tl) were used. Diabetic subjects on initial examination and retesting achieved a lower maximal heart rate and duration of exercise than control subjects. Abnormal electrocardiographic changes, thallium defects, or both were observed in 23/38 diabetic males (60.5%) on the first study and only one 65-year-old control subject had such findings. On retesting, the control subjects had no abnormalities while 76.9% of diabetic subjects had either 201Tl defects or ECG changes. We conclude that despite the fact that none of diabetic males had any clinical evidence or symptoms of heart disease, this high-risk group demonstrated abnormalities on exercise testing that merit careful subsequent evaluation and followup and could be an effective method of detecting early cardiac disease.

  1. Investigation of optimal acquisition time of myocardial perfusion scintigraphy using cardiac focusing-collimator

    NASA Astrophysics Data System (ADS)

    Niwa, Arisa; Abe, Shinji; Fujita, Naotoshi; Kono, Hidetaka; Odagawa, Tetsuro; Fujita, Yusuke; Tsuchiya, Saki; Kato, Katsuhiko

    2015-03-01

    Recently myocardial perfusion SPECT imaging acquired using the cardiac focusing-collimator (CF) has been developed in the field of nuclear cardiology. Previously we have investigated the basic characteristics of CF using physical phantoms. This study was aimed at determining the acquisition time for CF that enables to acquire the SPECT images equivalent to those acquired by the conventional method in 201TlCl myocardial perfusion SPECT. In this study, Siemens Symbia T6 was used by setting the torso phantom equipped with the cardiac, pulmonary, and hepatic components. 201TlCl solution were filled in the left ventricular (LV) myocardium and liver. Each of CF, the low energy high resolution collimator (LEHR), and the low medium energy general purpose collimator (LMEGP) was set on the SPECT equipment. Data acquisitions were made by regarding the center of the phantom as the center of the heart in CF at various acquisition times. Acquired data were reconstructed, and the polar maps were created from the reconstructed images. Coefficient of variation (CV) was calculated as the mean counts determined on the polar maps with their standard deviations. When CF was used, CV was lower at longer acquisition times. CV calculated from the polar maps acquired using CF at 2.83 min of acquisition time was equivalent to CV calculated from those acquired using LEHR in a 180°acquisition range at 20 min of acquisition time.

  2. Half-life measurements of isomeric states populated in projectile fragmentation

    SciTech Connect

    Bowry, M.; Podolay, Zs.

    2012-10-20

    The half-lives of excited isomeric states observed in {sup 195}Au, {sup 201}Tl and {sup 215}Rn are reported for the first time. Delayed {gamma}-rays were correlated with nuclei produced in the projectile fragmentation of relativistic {sup 238}U ions, unambiguously identified in terms of their atomic number (Z) and mass-to-charge ratio (A/Q) after traversing an in-flight separator. The observation of a long-lived isomeric state in {sup 195}Au with t{sub 1/2} = 16{sub -4}{sup +8}{mu}s is presented. Two shorter-lived isomeric states were detected in {sup 201}Tl and {sup 215}Rn with t{sub 1/2} = 95{sub -21}{sup +39} and 57{sub -12}{sup +21} ns respectively. In total 24 isomeric states were identified in different nuclei from Pt to Rn (A {approx} 200) during the current study, the majority of which were previously reported. The wealth of spectroscopic data provides the opportunity to determine the isomeric ratios over a wide range of Z, A and angular momentum (I h) of the reaction products. In particular, high-spin states with I Greater-Than-Or-Equivalent-To 18 h provide a robust test of theoretical models of fragmentation.

  3. Thallium 201 uptake in kidneys and heart as an indicator of prognosis in septic shock in the rat

    SciTech Connect

    Senda, M.; Ahmad, M.; Rubin, R.; Strauss, H.W.

    1989-03-01

    The change in distribution of cardiac output in septic shock was examined by radionuclide imaging with thallium 201 thallous chloride (/sup 201/Tl) which allows noninvasive evaluation of relative blood flow to various organs except for the brain. Pseudomonas aeruginosa (1 X 10(9)-2 X 10(10) organisms) were inoculated into the thigh of rats 18-24 hr before the study. The mean arterial pressure was measured with an intracarotid catheter. Fractional blood flow to the heart, kidneys, and liver was evaluated as organ uptake of /sup 201/Tl. Those with zero or less than 5% kidney uptake (n = 8) had a high heart uptake and all died within 3 hr even if their pressure was maintained. In contrast, 20 out of 24 rats with kidney uptake greater than 5% survived for more than 6 hr. Those results suggest that the kidney uptake, representing fractional renal blood flow, is an excellent indicator of short-term prognosis in septic shock.

  4. Half-life measurements of isomeric states populated in projectile fragmentation

    NASA Astrophysics Data System (ADS)

    Bowry, M.; Podolyák, Zs.; Kurcewicz, J.; Pietri, S.; Bunce, M.; Regan, P. H.; Farinon, F.; Geissel, H.; Nociforo, C.; Prochazka, A.; Weick, H.; Allegro, P.; Benlliure, J.; Benzoni, G.; Boutachkov, P.; Gerl, J.; Gorska, M.; Gottardo, A.; Gregor, N.; Janik, R.; Knöbel, R.; Kojouharov, I.; Kubo, T.; Litvinov, Y. A.; Merchan, E.; Mukha, I.; Naqvi, F.; Pfeiffer, B.; Pfützner, M.; Plaß, W.; Pomorski, M.; Riese, B.; Ricciardi, M. V.; Schmidt, K.-H.; Schaffner, H.; Kurz, N.; Denis Bacelar, A. M.; Bruce, A. M.; Farrelly, G. F.; Alkhomashi, N.; Al-Dahan, N.; Scheidenberger, C.; Sitar, B.; Spiller, P.; Stadlmann, J.; Strmen, P.; Sun, B.; Takeda, H.; Tanihata, I.; Terashima, S.; Valiente Dobon, J. J.; Winfield, J. S.; Wollersheim, H.-J.; Woods, P. J.

    2012-10-01

    The half-lives of excited isomeric states observed in 195Au, 201Tl and 215Rn are reported for the first time. Delayed γ-rays were correlated with nuclei produced in the projectile fragmentation of relativistic 238U ions, unambiguously identified in terms of their atomic number (Z) and mass-to-charge ratio (A/Q) after traversing an in-flight separator. The observation of a long-lived isomeric state in 195Au with t1/2 = 16-4+8 μs is presented. Two shorter-lived isomeric states were detected in 201Tl and 215Rn with t1/2 = 95-21+39 and 57-12+21 ns respectively. In total 24 isomeric states were identified in different nuclei from Pt to Rn (A ˜ 200) during the current study, the majority of which were previously reported. The wealth of spectroscopic data provides the opportunity to determine the isomeric ratios over a wide range of Z, A and angular momentum (I ħ) of the reaction products. In particular, high-spin states with I ≳ 18 ħ provide a robust test of theoretical models of fragmentation.

  5. Measurement of cross sections for {alpha}-induced reactions on {sup 197}Au and thick-target yields for the ({alpha},{gamma}) process on {sup 64}Zn and {sup 63}Cu

    SciTech Connect

    Basunia, M. S.; Smith, A. R.; Shugart, H. A.; Norman, E. B.

    2007-01-15

    We have measured the cross sections for the {sup 197}Au({alpha},{gamma}){sup 201}Tl and {sup 197}Au({alpha},2n){sup 199}Tl reactions in the 17.9- to 23.9-MeV energy range, and {sup 197}Au({alpha},n){sup 200}Tl reaction in the 13.4- to 23.9-MeV energy range using an activation technique. Thick-target yields for the {sup 64}Zn({alpha},{gamma}){sup 68}Ge (7- to 14-MeV) and {sup 63}Cu({alpha},{gamma}){sup 67}Ga (7-MeV) reactions were measured. For all measurements, natural elements were bombarded with He{sup +} beams from the 88 In. Cyclotron at the Lawrence Berkeley National Laboratory (LBNL). Irradiated samples were counted using a {gamma}-spectrometry system at LBNL's Low Background Facility. Measured {sup 197}Au({alpha},{gamma}){sup 201}Tl cross sections were compared with the NON-SMOKER theoretical values. The thick-target yields for the {sup 64}Zn({alpha},{gamma}){sup 68}Ge and {sup 63}Cu({alpha},{gamma}){sup 67}Ga reactions are also compared with the theoretical yield, calculated numerically using the energy dependent NON-SMOKER cross section data. In both cases, measured values are found to follow a trend of overlapping the predicted value near the alpha nucleus barrier height and fall below with a slowly widening difference between them in the sub-barrier energy points.

  6. Peritoneal fluid causing inferior attenuation on SPECT thallium-201 myocardial imaging in women

    SciTech Connect

    Rab, S.T.; Alazraki, N.P.; Guertler-Krawczynska, E.

    1988-11-01

    On SPECT thallium images, myocardial left ventricular (LV) anterior wall attenuation due to breast tissue is common in women. In contrast, in men, inferior wall counts are normally decreased compared to anterior counts. The purpose of this report is to describe cases of inferior wall attenuation of counts in women caused by peritoneal fluid, not myocardial disease. Twelve consecutive SPECT thallium myocardial studies performed in women on peritoneal dialysis, being evaluated for kidney transplant, were included in this study. For all studies, 3.5 mCi 201Tl were injected intravenously. Thirty-two images were acquired over 180 degrees (45 degrees RAO progressing to 45 degrees LPO) at 40 sec per stop. SPECT images were reviewed in short axis, horizontal long and vertical long axes. Data were also displayed in bullseye format with quantitative comparison to gender-matched normal files. Ten of 12 female patients studied had inferior wall defects on images, confirmed by bullseye display. All patients had approximately 2 liters of peritoneal fluid. Review of planar rotational views showed diaphragm elevation and fluid margin attenuations affecting left ventricular inferior wall. Thus, peritoneal fluid is a cause of inferior attenuation on 201Tl cardiac imaging.

  7. Computer-assisted superimposition of magnetic resonance and high-resolution technetium-99m-HMPAO and thallium-201 SPECT images of the brain

    SciTech Connect

    Holman, B.L.; Zimmerman, R.E.; Johnson, K.A.; Carvalho, P.A.; Schwartz, R.B.; Loeffler, J.S.; Alexander, E.; Pelizzari, C.A.; Chen, G.T. )

    1991-08-01

    A method for registering three-dimensional CT, MR, and PET data sets that require no special patient immobilization or other precise positioning measures was adapted to high-resolution SPECT and MRI and was applied in 14 subjects (five normal volunteers, four patients with dementia (Alzheimer's disease), two patients with recurrent glioblastoma, and three patients with focal lesions (stroke, arachnoid cyst and head trauma)). T2-weighted axial magnetic resonance images and transaxial 99mTc-HMPAO and 201Tl images acquired with an annular gamma camera were merged using an objective registration (translation, rotation and rescaling) program. In the normal subjects and patients with dementia and focal lesions, focal areas of high uptake corresponded to gray matter structures. Focal lesions observed on MRI corresponded to perfusion defects on SPECT. In the patients who had undergone surgical resection of glioblastoma followed by interstitial brachytherapy, increased 201Tl corresponding to recurrent tumor could be localized from the superimposed images. The method was evaluated by measuring the residuals in all subjects and translational errors due to superimposition of deep structures in the 12 subjects with normal thalamic anatomy and 99mTc-HMPAO uptake. This method for superimposing magnetic resonance and high-resolution SPECT images of the brain is a useful technique for correlating regional function with brain anatomy.

  8. Exercise beyond menopause: Dos and Don’ts

    PubMed Central

    Mishra, Nalini; Mishra, V. N.; Devanshi

    2011-01-01

    With a significant number of women belonging to the status of menopause and beyond, it is imperative to plan a comprehensive health program for them, including lifestyle modifications. Exercise is an integral part of the strategy. The benefits are many, most important being maintenance of muscle mass and thereby the bone mass and strength. The exercise program for postmenopausal women should include the endurance exercise (aerobic), strength exercise and balance exercise; it should aim for two hours and 30 minutes of moderate aerobic activity each week. Every woman should be aware of her target heart rate range and should track the intensity of exercise employing the talk test. Other deep breathing, yoga and stretching exercises can help to manage the stress of life and menopause-related symptoms. Exercises for women with osteoporosis should not include high impact aerobics or activities in which a fall is likely. The women and the treating medical practitioner should also be aware of the warning symptoms and contraindications regarding exercise prescription in women beyond menopause. The role of exercise in hot flashes, however, remains inconclusive. Overall, exercising beyond menopause is the only noncontroversial and beneficial aspect of lifestyle modification and must be opted by all. PMID:22408332

  9. Face mask ventilation--the dos and don'ts.

    PubMed

    Wood, Fiona E; Morley, Colin J

    2013-12-01

    Face mask ventilation provides respiratory support to newly born or sick infants. It is a challenging technique and difficult to ensure that an appropriate tidal volume is delivered because large and variable leaks occur between the mask and face; airway obstruction may also occur. Technique is more important than the mask shape although the size must appropriately fit the face. The essence of the technique is to roll the mask on to the face from the chin while avoiding the eyes, with a finger and thumb apply a strong even downward pressure to the top of the mask, away from the stem and sloped sides or skirt of the mask, place the other fingers under the jaw and apply a similar upward pressure. Preterm infants require continuous end-expiratory pressure to facilitate lung aeration and maintain lung volume. This is best done with a T-piece device, not a self-inflating or flow-inflating bag. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. ORAMUS(DOS). Ozone Risk AssessMent Utilities

    SciTech Connect

    Whitfield, R.G.; Jusko, M.J.; Biller, W.F.

    1998-12-01

    ORAMUS is a user-friendly, menu-driven software system that calculates and displays user-selected risk estimates for health effects attributable to short-term exposure to tropospheric ozone. Inputs to the risk assessment are estimates of exposure to ozone and exposure-response relationships to produce overall risk estimates in the form of probability distributions. Three fundamental models are included: headcount risk, benchmark risk, and hospital admissions. Exposure-response relationships are based on results of controlled human exposure studies. Exposure estimates are based on the EPA`s probabilistic national ambient air quality standards (NAAQS) exposure model, pNEM/Osub3, which simulates air quality associated with attainment of alternative NAAQS. Using ORAMUS, risk results for 27 air quality scenarios, air quality in 9 urban areas, 33 acute health endpoints, and 4 chronic health endpoints can be calculated.

  11. Los Dos Mundos: Rural Mexican Americans, Another America.

    ERIC Educational Resources Information Center

    Baker, Richard

    This book explores race relations between Mexican Americans and Anglo Americans in "Middlewest," a fictitious name for an actual rural Idaho community with the highest proportion of Mexican Americans in the state. Many Mexican Americans in this predominantly agricultural area are current or former migrant workers. The first chapter…

  12. Dos and Don'ts for a Fabulous Pedicure

    MedlinePlus

    ... stick under your nails. This helps keep your nails clean and removes the dirt, glitter, and other types of build-up you may not be able to see. Do bring your own pedicure utensils to the salon. Why? Because bacteria and fungus can move easily from one person to the ...

  13. Dos and don’ts in response priming research

    PubMed Central

    Schmidt, Filipp; Haberkamp, Anke; Schmidt, Thomas

    2011-01-01

    Response priming is a well-understood but sparsely employed paradigm in cognitive science. The method is powerful and well-suited for exploring early visuomotor processing in a wide range of tasks and research fields. Moreover, response priming can be dissociated from visual awareness, possibly because it is based on the first sweep of feedforward processing of primes and targets. This makes it a theoretically interesting device for separating conscious and unconscious vision. We discuss the major opportunities of the paradigm and give specific recommendations (e.g., tracing the time-course of priming in parametric experiments). Also, we point out typical confounds, design flaws, and data processing artifacts. PMID:22253674

  14. 48 CFR 632.702-70 - DOS policy.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... incremental funding of cost-reimbursement contracts. Fixed-price, labor-hour, and time-and-materials contracts... requirements office, justifying the need for incremental funding due to the unavailability of funds. ...

  15. Dos and Don'ts for Beginning Teachers.

    ERIC Educational Resources Information Center

    Armstrong, Coleen

    1993-01-01

    Beginning teachers are advised to pace themselves; provide disciplinary options; learn to justify their teaching; be tolerant about student gripes; use the Socratic method to elicit thoughtful responses; refrain from killing discussion, solving students' personal problems, and insulting students' intelligence; listen to veteran teachers; begin…

  16. CRONUS, A Distributed Operating System: CRONUS DOS Implementation.

    DTIC Science & Technology

    This is the final report for the second contract phase for development of the CRONUS Project. CRONUS is the name given to the distributed operating...Force Rome Air Development Center (RADC). The project was begun in 1981. The CRONUS distributed operating system is intended to promote resources...remote data, to collections of complex subsystems tailored to take advantage of a distributed architecture. One of the main contributions of CRONUS is

  17. Treating rheumatic diseases in pregnancy: dos and don'ts

    PubMed Central

    Lockshin, M D

    2006-01-01

    This paper presents a critical appraisal of the current evidence and recommendations regarding the use of pharmaceuticals and biologicals in pregnancy. Clinical experience is often at variance with published recommendations as studies have not taken into account the differences in physiology in the various stages of gestation and between animal and human pregnancies. Physicians should bear in mind that pregnancy causes disruption in several organ systems; the effects of an intervention may depend on the stage of gestation; and some effects of interventions in pregnancy may not manifest until adulthood. PMID:17038475

  18. Los Dos Mundos: Rural Mexican Americans, Another America.

    ERIC Educational Resources Information Center

    Baker, Richard

    This book explores race relations between Mexican Americans and Anglo Americans in "Middlewest," a fictitious name for an actual rural Idaho community with the highest proportion of Mexican Americans in the state. Many Mexican Americans in this predominantly agricultural area are current or former migrant workers. The first chapter…

  19. Dos and Don'ts for Beginning Teachers.

    ERIC Educational Resources Information Center

    Armstrong, Coleen

    1993-01-01

    Beginning teachers are advised to pace themselves; provide disciplinary options; learn to justify their teaching; be tolerant about student gripes; use the Socratic method to elicit thoughtful responses; refrain from killing discussion, solving students' personal problems, and insulting students' intelligence; listen to veteran teachers; begin…

  20. Dos Hermanas Chicanas: Overcoming Barriers to Professional Advancement

    ERIC Educational Resources Information Center

    Prospero, Moises

    2007-01-01

    Women and ethnic minorities face steep barriers to professional advancement, and those who rise to the executive level typically use a variety of strategies to overcome obstacles in their way. This study first reviewed the literature on barriers to professional advancement for women and ethnic minorities and the strategies that they report using…

  1. Dos and Don'ts of Writing Presidential Contracts

    ERIC Educational Resources Information Center

    Fain, Paul

    2006-01-01

    In the not-so-distant past, an employment agreement between a university president and a governing board was often nothing more than a handshake. Today, formal contracts are requirements for presidents, with boards and presidents typically relying on lawyers to extensively document terms of employment, salary and benefits, and, perhaps most…

  2. Estudo da Polarizacao dos Hiperons $\\Xi^-$ E $\\Omega^-$

    SciTech Connect

    Carvalho De Gouvea, Andre Luiz

    1995-01-01

    ln this thesis the polarization of the $\\Xi^-$ hyperon and the $\\Xi^+$ antihyperon produced in the Fermilab Experiment E791 was determined by the analysis of the weak decay $\\Xi^- \\to \\Lambda^0 + \\pi^-$. For $\\Xi^-$ produced in the interaction between a 500 GeV/c $\\pi^-$ beam and a unpolarized carbon (platinum) target in the region $p_t$ > 0.8 GeV/c and $X_F$ > 0, -10.9% ± 1.5% (-14.7% ± 3.1%) polarization was obtained perpendicular to the production plane and -5.92% ± 1.69% (-2.41%±3.53% $\\approx O$) polarization was measured for $\\Xi^+$. Evidence was also found for a polarized $\\Omega^-$ hyperon produced in the same experiment in the region $X_F$ >0, after analysis of the weak decay $\\Omega^- \\to \\Lambda^0 + K^-$.

  3. Evolution of the Astronomy Concepts Along Basic Education Cycle. (Breton Title: Evolução dos Conceitos de Astronomia no Decorrer da Educação Básica.) La Evolución de los Conceptos de Astronomía Durante la Educación Básica

    NASA Astrophysics Data System (ADS)

    Darroz, Luiz Marcelo; da Rosa, Cleci Werner; Becker da Rosa, Álvaro; Samudio Pèrez, Carlos Ariel

    2014-07-01

    learning of astronomy in basic education. Embora a astronomia seja considerada uma das ciências mais antigas da humanidade e ainda que a compreensão de seus conceitos tenha trazido enormes avanços para a Ciência e, consequentemente, para a sociedade, observa-se que uma parcela significativa de pessoas encontra-se à margem desses conhecimentos. De acordo com os Parâmetros Curriculares Nacionais para a Educação Básica, cabe à escola a difusão dos conceitos cientificamente corretos, entre eles os relacionados à área de astronomia. Pertinente a essa questão, apresenta-se uma pesquisa realizada com 140 estudantes do nono ano do ensino fundamental e com 120 estudantes da terceira série do ensino médio de quatro escolas da região de Passo Fundo/RS. Buscou-se averiguar, por meio de um questionário composto de questões abertas e de múltipla escolha, o conhecimento desse grupo de estudantes acerca de termos e fenômenos astronômicos básicos e, também, verificar se o índice de acertos cresce à medida que eles avançam nas diferentes e gradativas séries dos ensinos fundamental e médio. De modo geral, os resultados apresentados demonstram que o ensino de astronomia na educação básica enfrenta deficiências. Das 20 questões investigadas, em 17 os índices de acertos são semelhantes nas respostas dadas por estudantes de nível fundamental e médio, revelando que muitas concepções equivocadas permanecem ao longo da educação básica. Isso evidencia que tais temas não são - ou são pouco - abordados durante esses dois níveis de escolarização. Assim, conclui-se que a discussão dos conceitos relacionados com a astronomia deve receber maior ênfase na abordagem dos diferentes conteúdos, sendo necessária uma ação nacional em prol do seu ensino. Acredita-se que essa ação nacional deve estar apoiada em um pilar triplo de atores coletivos: comunidade científica, comunidade astronômica semiprofissional e comunidade escolar. Por fim, esse pilar seria

  4. Difficulties of First Years Elementary School Teachers with the Teaching of Astronomy. (Breton Title: Dificuldades de Professores dos Anos Iniciais do Ensino Fundamental em Relação ao Ensino da Astronomia. ) Dificultades de LOS Profesores de los Primeros Años de la Escuela Primaria en Relación a la Enseñanza de la Astronomía

    NASA Astrophysics Data System (ADS)

    Langhi, Rodolfo; Nardi, Roberto

    2005-12-01

    This paper reports Primary School teachers' discourses analysis about their difficulties related to the teaching of Astronomy. It reports partial data of a master's level research carried out in the last two years, named "An exploratory study for inserting Astronomy in primary school teachers' education" (LANGHI, 2004). The study took into consideration students' and teachers' common sense conceptions about astronomical phenomena, conceptual mistakes in textbooks, and Astronomy's suggestions given by the PCN (Parâmetros Curriculares Nacionais - The Brazilian National Curriculum Standards). The paper aims to characterize teachers' difficulties, in order to provide subsides to the implementation of an initial or continuing education program. This study is justified by the fact that courses plans like these only will be adapted to the teacher's (and students') reality, if there is a primary investigation about what the teachers really need to know about Astronomy. This fact was possible here by the enunciations interpretation of a teachers' sample using semi-structured interviews, according to discourse analysis procedures. The research outcomes show difficulties related to factors like: those of personal order, methodological, on teacher's formation, educational infrastructure and other related to information sources for educators. Este artigo, que relata as dificuldades de professores em relação ao ensino da Astronomia, faz parte de um estudo exploratório para a inserção da Astronomia na formação de professores dos anos iniciais do Ensino Fundamental. Esse estudo leva em consideração as concepções alternativas de alunos e professores sobre fenômenos astronômicos, os erros conceituais em livros didáticos e as sugestões de conteúdos de Astronomia constantes nos PCN (Parâmetros Curriculares Nacionais). Caracterizar as dificuldades dos professores é a questão central deste texto, apontando para o objetivo de contribuir com subsídios para um futuro

  5. Thallium-201 Uptake of Giant Cell Tumor: One Step Toward the Differential Diagnosis to Atypically Presenting Osteosarcoma.

    PubMed

    Keller, Sarah; Inai, Ryota; Sato, Shuhei; Tada, Akihiro; Adam, Gerhard; Yamamura, Jin; Kanazawa, Susumu

    2017-01-01

    The radiologic differential diagnosis of giant cell tumors (GCTs) is challenging because there is a risk of misdiagnosis of GCTs as malignant lesions such as atypically presenting osteosarcomas (OSs). This study aims to assess the feasibility of (201)Tl scintigraphy for the differential diagnosis of GCT and atypical OS. Thallium-201 scintigraphy scans obtained between January 2006 and October 2015 of patients with histologically proven GCT (23 patients [male-to-female ratio, 15:8]; median age, 33.0 years; age range, 20-61 years) and patients with atypically presenting OS (20 patients [male-to-female ratio, 11:9]; median age, 30.0 years; age range, 12-69 years) were retrospectively reviewed. Morphologic classification of osseous lesions was performed on radiographs and CT scans. The (201)Tl scintigraphy-based tumor-to-background contrast (TBC) and washout rate (WR) were calculated on early phase and delayed phase scans. The laboratory parameters lactate dehydrogenase (LDH), C-reactive protein (CRP), and alkaline phosphatase were obtained. Statistical significance was estimated using the Mann-Whitney U test. Cutoff values were calculated for early phase TBC and delayed phase TBC. Twenty-two of 23 GCTs were detected on the initial radiographs, whereas only six of 20 atypical OSs were detected on the initial radiographs. The early phase TBC was increased in GCT (median, 2.59; range, 0.51-12.26) compared with atypical OS (median, 1.68; range, 0.90-6.45) (p = 0.07). The delayed phase TBC was increased in GCT (median, 1.65; range, 0.22-5.26) compared with atypical OS (median, 0.96; range, 0.39-3.76) (p = 0.02). The median WR was not significantly decreased in GCT. The cutoff value for the early phase TBC was 3.90, and the cutoff value for the delayed phase TBC was 1.64; these cutoff values for early and delayed phase TBC yielded a sensitivity of 80.0% and a specificity of 47.8% and 52.2% respectively. Serum LDH (mean: atypical OS vs GCT, 215.5 vs 170.5 U/L, respectively

  6. IQ-SPECT for thallium-201 myocardial perfusion imaging: effect of normal databases on quantification.

    PubMed

    Konishi, Takahiro; Nakajima, Kenichi; Okuda, Koichi; Yoneyama, Hiroto; Matsuo, Shinro; Shibutani, Takayuki; Onoguchi, Masahisa; Kinuya, Seigo

    2017-07-01

    Although IQ-single-photon emission computed tomography (SPECT) provides rapid acquisition and attenuation-corrected images, the unique technology may create characteristic distribution different from the conventional imaging. This study aimed to compare the diagnostic performance of IQ-SPECT using Japanese normal databases (NDBs) with that of the conventional SPECT for thallium-201 ((201)Tl) myocardial perfusion imaging (MPI). A total of 36 patients underwent 1-day (201)Tl adenosine stress-rest MPI. Images were acquired with IQ-SPECT at approximately one-quarter of the standard time of conventional SPECT. Projection data acquired with the IQ-SPECT system were reconstructed via an ordered subset conjugate gradient minimizer method with or without scatter and attenuation correction (SCAC). Projection data obtained using the conventional SPECT were reconstructed via a filtered back projection method without SCAC. The summed stress score (SSS) was calculated using NDBs created by the Japanese Society of Nuclear Medicine working group, and scores were compared between IQ-SPECT and conventional SPECT using the acquisition condition-matched NDBs. The diagnostic performance of the methods for the detection of coronary artery disease was also compared. SSSs were 6.6 ± 8.2 for the conventional SPECT, 6.6 ± 9.4 for IQ-SPECT without SCAC, and 6.5 ± 9.7 for IQ-SPECT with SCAC (p = n.s. for each comparison). The SSS showed a strong positive correlation between conventional SPECT and IQ-SPECT (r = 0.921 and p < 0.0001), and the correlation between IQ-SPECT with and without SCAC was also good (r = 0.907 and p < 0.0001). Regarding diagnostic performance, the sensitivity, specificity, and accuracy were 80.8, 78.9, and 79.4%, respectively, for the conventional SPECT; 80.8, 80.3, and 82.0%, respectively, for IQ-SPECT without SCAC; and 88.5, 86.8, and 87.3%, respectively, for IQ-SPECT with SCAC, respectively. The area under the curve obtained via receiver operating

  7. Optimal energy window selection of a CZT-based small-animal SPECT for quantitative accuracy

    NASA Astrophysics Data System (ADS)

    Park, Su-Jin; Yu, A. Ram; Choi, Yun Young; Kim, Kyeong Min; Kim, Hee-Joung

    2015-05-01

    Cadmium zinc telluride (CZT)-based small-animal single-photon emission computed tomography (SPECT) has desirable characteristics such as superior energy resolution, but data acquisition for SPECT imaging has been widely performed with a conventional energy window. The aim of this study was to determine the optimal energy window settings for technetium-99 m (99mTc) and thallium-201 (201Tl), the most commonly used isotopes in SPECT imaging, using CZT-based small-animal SPECT for quantitative accuracy. We experimentally investigated quantitative measurements with respect to primary count rate, contrast-to-noise ratio (CNR), and scatter fraction (SF) within various energy window settings using Triumph X-SPECT. The two ways of energy window settings were considered: an on-peak window and an off-peak window. In the on-peak window setting, energy centers were set on the photopeaks. In the off-peak window setting, the ratios of energy differences between the photopeak from the lower- and higher-threshold varied from 4:6 to 3:7. In addition, the energy-window width for 99mTc varied from 5% to 20%, and that for 201Tl varied from 10% to 30%. The results of this study enabled us to determine the optimal energy windows for each isotope in terms of primary count rate, CNR, and SF. We selected the optimal energy window that increases the primary count rate and CNR while decreasing SF. For 99mTc SPECT imaging, the energy window of 138-145 keV with a 5% width and off-peak ratio of 3:7 was determined to be the optimal energy window. For 201Tl SPECT imaging, the energy window of 64-85 keV with a 30% width and off-peak ratio of 3:7 was selected as the optimal energy window. Our results demonstrated that the proper energy window should be carefully chosen based on quantitative measurements in order to take advantage of desirable characteristics of CZT-based small-animal SPECT. These results provided valuable reference information for the establishment of new protocol for CZT

  8. Precordial ST-segment depression during acute inferior myocardial infarction: clinical, scintigraphic and angiographic correlations

    SciTech Connect

    Gibson, R.S.; Crampton, R.S.; Watson, D.D.; Taylor, G.J.; Carabello, B.A.; Holt, N.D.; Beller, G.A.

    1982-10-01

    The cause and associated pathophysiology of precordial ST-segment depression during acute inferior myocardial infarction (IMI) are controversial. To investigate this problem, electrocardiographic findings in 48 consecutive patients with acute IMI were prospectively compared with results of coronary angiography, submaximal exercise thallium-201 (/sup 201/Tl) scintigraphy and multigated blood pool imaging, all obtained 2 weeks after IMI, and with clinical follow-up at 3 months. Patients were classified according to the admission ECG obtained 3.3 +/- 3.1 hours after the onset of chest pain. Twenty-one patients (group A) had no or <1.0 mm ST-segment depression, and 27 (group B) had greater than or equal to1.0 mm ST-segment depression in two or more precordial (V/sub 1-6/) leads. Patients in group B had more prolonged chest pain after admission to the coronary care unit than those in group A (2.8 +/- 3.0 vs 1.2 +/- 1.1 hours, p<0.03), greater summed ST-segment elevation in leads II, III, aV/sub F/ (6.7 +/- 4.7 vs 3.3 +/- 4.5 mm, p<0.02), higher plasma peak creatine kinase levels (1133 +/- 781 vs 653 +/- 482 IU/l, p<0.01), a higher prevalence of ''true posterior'' infarction by ECG criteria (26% vs 5%, p<0.05), a lower radionuclide ejection fraction (46 +/- 9% vs 54 +/- 6%, p<0.001), more extensive infarct-related asynergy (p<0.001) and /sup 201/Tl perfusion abnormalities (p<0.01), more complications during hospitalization (p<0.03), and more cardiac events at 3 months (p<0.02). There were no significant differences between group A and group B in the extent of underlying coronary disease, prevalence of left anterior descending coronary artery disease, exercise-induced ST-segment depression or angina, /sup 201/Tl defects or wall motion abnormalities in anterior or septal segments.

  9. Evaluation of quantitative accuracy in CZT-based pre-clinical SPECT for various isotopes

    NASA Astrophysics Data System (ADS)

    Park, S.-J.; Yu, A. R.; Kim, Y.-s.; Kang, W.-S.; Jin, S. S.; Kim, J.-S.; Son, T. J.; Kim, H.-J.

    2015-05-01

    In vivo pre-clinical single-photon emission computed tomography (SPECT) is a valuable tool for functional small animal imaging, but several physical factors, such as scatter radiation, limit the quantitative accuracy of conventional scintillation crystal-based SPECT. Semiconductor detectors such as CZT overcome these deficiencies through superior energy resolution. To our knowledge, little scientific information exists regarding the accuracy of quantitative analysis in CZT-based pre-clinical SPECT systems for different isotopes. The aim of this study was to assess the quantitative accuracy of CZT-based pre-clinical SPECT for four isotopes: 201Tl, 99mTc, 123I, and 111In. The quantitative accuracy of the CZT-based Triumph X-SPECT (Gamma-Medica Ideas, Northridge, CA, U.S.A.) was compared with that of a conventional SPECT using GATE simulation. Quantitative errors due to the attenuation and scatter effects were evaluated for all four isotopes with energy windows of 5%, 10%, and 20%. A spherical source containing the isotope was placed at the center of the air-or-water-filled mouse-sized cylinder phantom. The CZT-based pre-clinical SPECT was more accurate than the conventional SPECT. For example, in the conventional SPECT with an energy window of 10%, scatter effects degraded quantitative accuracy by up to 11.52%, 5.10%, 2.88%, and 1.84% for 201Tl, 99mTc, 123I, and 111In, respectively. However, with the CZT-based pre-clinical SPECT, the degradations were only 9.67%, 5.45%, 2.36%, and 1.24% for 201Tl, 99mTc, 123I, and 111In, respectively. As the energy window was increased, the quantitative errors increased in both SPECT systems. Additionally, the isotopes with lower energy of photon emissions had greater quantitative error. Our results demonstrated that the CZT-based pre-clinical SPECT had lower overall quantitative errors due to reduced scatter and high detection efficiency. Furthermore, the results of this systematic assessment quantifying the accuracy of these SPECT

  10. Semi-automated measurements of heart-to-mediastinum ratio on 123I-MIBG myocardial scintigrams by using image fusion method with chest X-ray images

    NASA Astrophysics Data System (ADS)

    Kawai, Ryosuke; Hara, Takeshi; Katafuchi, Tetsuro; Ishihara, Tadahiko; Zhou, Xiangrong; Muramatsu, Chisako; Abe, Yoshiteru; Fujita, Hiroshi

    2015-03-01

    MIBG (iodine-123-meta-iodobenzylguanidine) is a radioactive medicine that is used to help diagnose not only myocardial diseases but also Parkinson's diseases (PD) and dementia with Lewy Bodies (DLB). The difficulty of the segmentation around the myocardium often reduces the consistency of measurement results. One of the most common measurement methods is the ratio of the uptake values of the heart to mediastinum (H/M). This ratio will be a stable independent of the operators when the uptake value in the myocardium region is clearly higher than that in background, however, it will be unreliable indices when the myocardium region is unclear because of the low uptake values. This study aims to develop a new measurement method by using the image fusion of three modalities of MIBG scintigrams, 201-Tl scintigrams, and chest radiograms, to increase the reliability of the H/M measurement results. Our automated method consists of the following steps: (1) construct left ventricular (LV) map from 201-Tl myocardium image database, (2) determine heart region in chest radiograms, (3) determine mediastinum region in chest radiograms, (4) perform image fusion of chest radiograms and MIBG scintigrams, and 5) perform H/M measurements on MIBG scintigrams by using the locations of heart and mediastinum determined on the chest radiograms. We collected 165 cases with 201-Tl scintigrams and chest radiograms to construct the LV map. Another 65 cases with MIBG scintigrams and chest radiograms were also collected for the measurements. Four radiological technologists (RTs) manually measured the H/M in the MIBG images. We compared the four RTs' results with our computer outputs by using Pearson's correlation, the Bland-Altman method, and the equivalency test method. As a result, the correlations of the H/M between four the RTs and the computer were 0.85 to 0.88. We confirmed systematic errors between the four RTs and the computer as well as among the four RTs. The variation range of the H

  11. How reliable is myocardial imaging in the diagnosis of acute myocardial infarction

    SciTech Connect

    Willerson, J.T.

    1983-01-01

    Myocardial scintigraphic techniques available presently allow a sensitive and relatively specific diagnosis of acute myocardial infarction when they are used correctly, although every technique has definite limitations. Small myocardial infarcts (less than 3 gm.) may be missed, and there are temporal limitations in the usefulness of the scintigraphic techniques. The development of tomographic methodology that may be used with single-photon radionuclide emitters (including technetium and /sup 201/Tl will allow the detection of relatively small abnormalities in myocardial perfusion and regions of myocardial infarction and will help to provide a more objective interpretation of the myocardial scintigrams. The use of overlay techniques allowing simultaneous assessment of myocardial perfusion, infarct-avid imaging, and radionuclide ventriculograms will provide insight into the relevant aspects of the extent of myocardial damage, the relationship of damage to myocardial perfusion, and the functional impact of myocardial infarction on ventricular performance.

  12. Risk stratification after myocardial infarction. Clinical overview

    SciTech Connect

    O'Rourke, R.A. )

    1991-09-01

    Many patients with an acute myocardial infarction can be stratified into subgroups that are at high risk for morbidity and mortality on the basis of clinical characteristics that indicate recurrent myocardial ischemia, persistent left ventricular dysfunction, and/or recurrent cardiac arrhythmias. In patients with uncomplicated myocardial infarction the assessment of symptoms, physical findings, and ECG changes during predischarge exercise testing often identifies patients at increased risk for further cardiac events. Because of the suboptimum sensitivity and specificity of the exercise ECG for detecting myocardial ischemia, myocardial perfusion imaging with 201Tl and/or assessment of global and segmental ventricular function by two-dimensional echocardiography or radionuclide cineangiography during or immediately after exercise are often added to the predischarge risk stratification.

  13. Half-life of the first excited state of {sup 201}Hg

    SciTech Connect

    Meot, V.; Morel, P.; Gosselin, G.

    2007-06-15

    The lifetime of the first excited state of {sup 201}Hg, populated by the {sup 201}Tl electron capture decay and subsequent {gamma}-ray transitions, has been measured for the first time. This measurement has been carried out using a coincidence between an internal conversion electron and a {gamma}-ray. The half-life of 81{+-}5 ns has been obtained and B(E2) and B(M1) values were deduced and compared to previous estimates. With these reduced matrix elements, the excitation rate of the first excited state of {sup 201}Hg in plasma have been calculated in the frame of a Nuclear excitation by electronic transition (NEET) process.

  14. Possibility of determination of the asymptotic level-density parameter

    SciTech Connect

    Kudyaev, G.A.; Ostapenko, Y.B.; Svirin, M.I.; Smirenkin, G.N.

    1988-02-01

    We investigate the sensitivity of the fissility of nuclei to the parameters of the density of excited levels and conclude that the nuclei in the region of Pb are most favorable for an experimental estimate of the asymptotic parameter a-italic-tilde = ..cap alpha..A. The mean value ..cap alpha.. = 0.086 +- 0.009 MeV/sup -1/ is found from analysis of the fission of seven nuclei from /sup 201/Tl to /sup 213/At. This value is in agreement with the phenomenological description of the energy dependence a(U) (..cap alpha.. = 0.093 MeV/sup -1/) and with the theoretical prediction ..cap alpha.. = 0.09 MeV/sup -1/ obtained for a Woods-Saxon potential.

  15. High-precision γ -ray spectroscopy of the cardiac PET imaging isotope Rb82 and its impact on dosimetry

    DOE PAGES

    Nino, M. N.; McCutchan, E. A.; Smith, S. V.; ...

    2016-02-01

    82Rb is a positron-emitting isotope used in cardiac positron emission tomography (PET) imaging which has been reported to deliver a significantly lower effective radiation dose than analogous imaging isotopes like 201Tl and 99mTc sestamibi. High-quality β-decay data are essential to accurately appraise the total dose received by the patients. A source of 82Sr was produced at the Brookhaven Linac Isotope Producer (BLIP), transported to Argonne National Laboratory, and studied with the Gammasphere facility. Significant revisions have been made to the level scheme of 82Kr including 12 new levels, 50 new γ-ray transitions, and the determination of many new spin assignmentsmore » through angular correlations. Lastly, these new high-quality data allow a precise reappraisal of the β-decay strength function and thus the consequent dose received by patients.« less

  16. The independent value of exercise thallium scintigraphy to physicians

    SciTech Connect

    Hlatky, M.; Botvinick, E.; Brundage, B.

    1982-11-01

    To determine the effect of exercise myocardial scintigraphy with /sup 201/Tl on diagnostic accuracy and the need for coronary angiography, consecutive patients with a variety of clinical presentations were identified. Clinical summaries, including a detailed history, physical examination, and complete data from a standard treadmill exercise test, were presented to 91 cardiologists. The cardiologists assessed the probability of coronary disease and the need for coronary angiography. They were then presented the results of thallium scintigraphy and revised their assessments if warranted. Scintigraphy significantly increased the cardiologists' diagnostic accuracy beyond that attained with other clinical information (p less than 0.0001). The change in accuracy varied from + 4% to + 20% in different patient groups, and was greatest in patients with atypical angina and a positive exercise ECG. Ratings of the need for coronary angiography changed from -13% to +21% in different patient groups. We conclude that exercise thallium scintigraphy can provide independent diagnostic information and influence the need for coronary angiography.

  17. Exercise supplementation of dipyridamole for myocardial perfusion imaging

    SciTech Connect

    DePuey, E.G.

    1991-08-01

    The substitution of intravenous dipyridamole for symptom-limited treadmill exercise has provided a non-invasive means to diagnose coronary artery disease with 201Tl scintigraphy in patients unable to adequately exercise. Limitations of dipyridamole/thallium imaging are primarily due to suboptimal image quality secondary to hepatic tracer concentration and decreased test sensitivity in patients who are dipyridamole non-responders. Low-level treadmill exercise supplementation improves image quality, whereas handgrip has little, if any, benefit. The effect of low-level exercise in augmenting coronary blood flow is unknown and reports regarding the effect of handgrip are conflicting. The diagnostic benefit of these maneuvers in improving test sensitivity and decreasing the number of non-responders has not been documented. The combination of maximal, symptom-limited treadmill exercise and intravenous dipyridamole is a theoretically attractive option to improve overall test sensitivity, but the physiologic consequences and potential side effects should be more thoroughly investigated.

  18. Age-specific inhalation radiation dose commitment factors for selected radionuclides

    SciTech Connect

    Strenge, D.L.; Peloquin, R.A.; Baker, D.A.

    1982-08-01

    Inhalation dose commitment factors are presented for selected radionuclides for exposure of individuals in four age groups: infant, child, teen and adult. Radionuclides considered are /sup 35/S, /sup 36/Cl, /sup 45/Ca, /sup 67/Ga, /sup 75/Se, /sup 85/Sr, /sup 109/Cd, /sup 113/Sn, /sup 125/I, /sup 133/Ba, /sup 170/Tm, /sup 169/Yb, /sup 182/Ta, /sup 192/Ir, /sup 198/Au, /sup 201/Tl, /sup 204/Tl, and /sup 236/Pu. The calculational method is based on the human metabolic model of ICRP as defined in Publication 2 (ICRP 1959) and as used in previous age-specific dose factor calculations by Hoenes and Soldat (1977). Dose commitment factors are presented for the following organs of reference: total body, bone, liver, kidney, thyroid, lung and lower large intestine.

  19. Cerebral necrosis after 25Gy radiotherapy in childhood followed 28 years later by 54Gy radiotherapy.

    PubMed

    Koot, Radboud W; Stalpers, Lukas J A; Aronica, Eleonora; Andries Bosch, D

    2007-09-01

    The development of brain necrosis is life-long risk of repeat radiation therapy, even after a long time interval and a moderate radiation dose. We report on a 34-year-old patient who had prophylactic cranial irradiation with 25Gy and adjuvant chemotherapy in childhood for leukaemia and in adulthood, 28 years later, therapeutic radiotherapy with 54Gy for an atypical (WHO grade II) meningioma. About 2 years later he developed a contrast-enhancing lesion on MRI-scan that was indicative of a tumor according to a thallium-201 ((201)Tl) SPECT scan. Histopathology of the operated contrast-enhancing lesion showed extensive radionecrosis. Radiation necrosis is a small but serious risk after repeat radiation therapy, even after a very long-term interval, the delivery of small fractions and an average cumulative total dose. Patients undergoing repeat radiotherapy therefore need to be followed life-long for potential late radiation toxicity.

  20. Preconcentration and Assay of Radionuclides with Self Assembled Monolayers on Mesoporous Supports

    SciTech Connect

    Addleman, Raymond S.; Egorov, Oleg B.; O'Hara, Matthew J.; Busche, Brad J.; Zemanian, Thomas S.; Fryxell, Glen E.

    2005-01-01

    An analytical system is suggested to separate a number of elements of the Periodic Table in a hydrogen or oxygen stream at temperatures up to 1400 C. High temperature chemical filters are used to separate volatile products. The approach has demonstrated its efficiency in a number of examples of carrier-free isotope production from targets irradiated at an accelerator: 109Cd from In; 22Na from Al; 72Se from GaAs; 188Pt, 183Re, 185Os and 201Tl from Pb or Bi; separation of Po from Pb and Bi, etc. Another application of high temperature chemical sublimation of elements and oxides was realized in activation analysis of noble metals in various ores and samples.

  1. Excitation functions for complete-fusion and transfer reactions in {sup 4}He interaction with {sup 197}Au nuclei

    SciTech Connect

    Kulko, A. A.; Demekhina, N. A.; Kalpakchieva, R.; Muzychka, Yu. A.; Penionzhkevich, Yu. E.; Rassadov, D. N.; Skobelev, N. K.; Testov, D. A.

    2007-04-15

    Excitation functions are measured for the fusion reactions {sup 197}Au({sup 4}He, xn){sup 201-xn}Tl that are induced by alpha-particle interaction with gold nuclei in the energy range 14-36 MeV and in which x neutrons (0 {<=} x {<=} 3) are evaporated. The stack-activation technique was used to record and separate reaction products. Experimental data on the fusion reactions followed by evaporation of one to three neutrons agree with results of previous studies. For the radiative-capture reaction {sup 197}Au({sup 4}He,{gamma}){sup 201}Tl, the upper limit on the cross section proved to be much lower. The excitation functions for the reactions subjected to measurements are compared with the results of calculations based on the statistical model and with the results of an experiment performed previously in a {sup 6}He beam.

  2. Thallium-201 myocardial SPECT in a patient with mirror-image dextrocardia and left bundle branch block.

    PubMed

    Turgut, Bülent; Kitapci, Mehmet T; Temiz, N Hakan; Unlü, Mustafa; Erselcan, Taner

    2003-09-01

    A 53-year-old male patient with a previous diagnosis of situs inversus with mirror-image dextrocardia underwent thallium-201 (Tl-201) stress-redistribution myocardial perfusion single photon emission computed tomography (SPECT). Electrocardiogram (ECG) obtained on right hemithorax revealed constant complete left bundle branch block. Tl-201 stress-redistribution SPECT images revealed abnormal perfusion with reversible ischemia in the anteroseptal, septal and inferoseptal walls. Coronary angiography performed 1 month after SPECT study was normal. This case illustrates that false positive reversible perfusion defects can be seen in patients with mirror-image dextrocardia associated with constant complete left bundle branch block. To our knowledge, this is the first reported case of mirror-image dextrocardia and constant complete left bundle branch block with false positive Tl-201 SPECT findings.

  3. Development of a multispectral autoradiography using a coded aperture

    NASA Astrophysics Data System (ADS)

    Noto, Daisuke; Takeda, Tohoru; Wu, Jin; Lwin, Thet T.; Yu, Quanwen; Zeniya, Tsutomu; Yuasa, Tetsuya; Hiranaka, Yukio; Itai, Yuji; Akatsuka, Takao

    2000-11-01

    Autoradiography is a useful imaging technique to understand biological functions using tracers including radio isotopes (RI's). However, it is not easy to describe the distribution of different kinds of tracers simultaneously by conventional autoradiography using X-ray film or Imaging plate. Each tracer describes each corresponding biological function. Therefore, if we can simultaneously estimate distribution of different kinds of tracer materials, the multispectral autoradiography must be a quite powerful tool to better understand physiological mechanisms of organs. So we are developing a system using a solid state detector (SSD) with high energy- resolution. Here, we introduce an imaging technique with a coded aperture to get spatial and spectral information more efficiently. In this paper, the imaging principle is described, and its validity and fundamental property are discussed by both simulation and phantom experiments with RI's such as 201Tl, 99mTc, 67Ga, and 123I.

  4. Heavy-ion versus 3He/4He fusion-fission reactions: Angular momentum dependence of dissipation in nuclear fission

    NASA Astrophysics Data System (ADS)

    Ye, W.

    2011-09-01

    The stochastic Langevin model is employed to study dissipation properties in fission in the 16O + 181Ta →197Tl system by analyzing prescission neutron yields measured in this reaction. It has been found that the 197Tl nuclei undergo fission that is not in accordance with the standard Bohr-Wheeler statistical theory. A detailed comparison with previously published work in which fission excitation functions measured in 3,4He + 197Au →200,201Tl are shown to be in excellent agreement with the fission width formula predicted by the traditional models of nuclear fission suggests that nuclear dissipation strength may have an angular momentum dependence in addition to the known deformation and temperature dependence. Implications for the basic understanding of the observed abnormal rise in prescission particles at high energy and the need for further experimental confirmations are discussed.

  5. Excitation Functions for Complete Fusion and Transfer Reactions in the Interaction of 4He Nuclei with 197Au

    NASA Astrophysics Data System (ADS)

    Kulko, A. A.; Demekhina, N. A.; Kalpakchieva, R.; Muzychka, Yu. A.; Penionzhkevich, Yu. E.; Rassadov, D. N.; Skobelev, N. K.; Testov, D. A.

    2007-05-01

    Excitation functions have been measured for the fusion reaction 197Au(αxn)201-xnTl with the evaporation of x neutrons (0⩽x⩽3) in the energy range 14-36 MeV. The induced-activation method was used for registration and identification of the reaction products. The experimental cross sections for the (1-3)-neutron evaporation residues are in good agreement with the results known from literature. For the radiation capture reaction 197Au(α,γ)201Tl, the upper limit was obtained essentially lower. The excitation functions for the measured reactions are compared with calculations in the frame of the statistical model, as well as with formerly measured similar data with a 6He beam.

  6. Excitation Functions for Complete Fusion and Transfer Reactions in the Interaction of 4He Nuclei with 197Au

    SciTech Connect

    Kulko, A. A.; Demekhina, N. A.; Kalpakchieva, R.; Muzychka, Yu. A.; Penionzhkevich, Yu. E.; Rassadov, D. N.; Skobelev, N. K.; Testov, D. A.

    2007-05-22

    Excitation functions have been measured for the fusion reaction 197Au({alpha}xn)201-xnTl with the evaporation of x neutrons (0{<=}x{<=}3) in the energy range 14-36 MeV. The induced-activation method was used for registration and identification of the reaction products. The experimental cross sections for the (1-3)-neutron evaporation residues are in good agreement with the results known from literature. For the radiation capture reaction 197Au({alpha},{gamma})201Tl, the upper limit was obtained essentially lower. The excitation functions for the measured reactions are compared with calculations in the frame of the statistical model, as well as with formerly measured similar data with a 6He beam.

  7. Excitation functions for complete-fusion and transfer reactions in 4He interaction with 197Au nuclei

    NASA Astrophysics Data System (ADS)

    Kulko, A. A.; Demekhina, N. A.; Kalpakchieva, R.; Muzychka, Yu. A.; Penionzhkevich, Yu. E.; Rassadov, D. N.; Skobelev, N. K.; Testov, D. A.

    2007-04-01

    Excitation functions are measured for the fusion reactions 197Au(4He, xn)201-xn Tl that are induced by alpha-particle interaction with gold nuclei in the energy range 14 36 MeV and in which x neutrons (0 ≤ x ≤ 3) are evaporated. The stack-activation technique was used to record and separate reaction products. Experimental data on the fusion reactions followed by evaporation of one to three neutrons agree with results of previous studies. For the radiative-capture reaction 197Au(4He,γ)201Tl, the upper limit on the cross section proved to be much lower. The excitation functions for the reactions subjected to measurements are compared with the results of calculations based on the statistical model and with the results of an experiment performed previously in a 6He beam.

  8. High-precision γ -ray spectroscopy of the cardiac PET imaging isotope 82Rb and its impact on dosimetry

    NASA Astrophysics Data System (ADS)

    Nino, M. N.; McCutchan, E. A.; Smith, S. V.; Lister, C. J.; Greene, J. P.; Carpenter, M. P.; Muench, L.; Sonzogni, A. A.; Zhu, S.

    2016-02-01

    82Rb is a positron-emitting isotope used in cardiac positron emission tomography (PET) imaging which has been reported to deliver a significantly lower effective radiation dose than analogous imaging isotopes like 201Tl and 99 mTc sestamibi. High-quality β -decay data are essential to accurately appraise the total dose received by the patients. A source of 82Sr was produced at the Brookhaven Linac Isotope Producer (BLIP), transported to Argonne National Laboratory, and studied with the Gammasphere facility. Significant revisions have been made to the level scheme of 82Kr including 12 new levels, 50 new γ -ray transitions, and the determination of many new spin assignments through angular correlations. These new high-quality data allow a precise reappraisal of the β -decay strength function and thus the consequent dose received by patients.

  9. Critical behavior in the variation of GDR width at low temperature

    NASA Astrophysics Data System (ADS)

    Pandit, Deepak; Mukhopadhyay, S.; Pal, Surajit; De, A.; Banerjee, S. R.

    2012-07-01

    We present the first experimental giant dipole resonance (GDR) width systematics, in the temperature region 0.8-1.2 MeV for 201Tl, a near Pb nucleus, to investigate the evolution of the GDR width in shell effect and pairing dominated region. The extracted GDR widths are well below the predictions of shell effect corrected thermal shape fluctuation model (TSFM) and thermal pairing included phonon damping model. A similar behavior of the GDR width is also observed for 63Cu measured in the present work and 119Sb, measured earlier. This discrepancy is attributed to the GDR induced quadrupole moment leading to a critical point in the increase of the GDR width with temperature. We incorporate this novel idea in the phenomenological description based on the TSFM for a better understanding of the GDR width systematics for the entire range of mass, spin and temperature.

  10. The South African National Accelerator Centre: particle therapy and isotope production programmes

    NASA Astrophysics Data System (ADS)

    Jones, D. T. L.; Mills, S. J.

    1998-06-01

    The National Accelerator Centre (NAC) provides facilities for basic and applied research, radioisotope production and particle therapy. To date, 851 patients have been treated on the 66 MeV p+Be isocentric neutron therapy unit while 191 patients have been treated (mainly for intracranial conditions) on the 200 MeV horizontal proton beam facility. A variety of radioisotopes such as 67Ga, 81Rb/ 81Kr, 111In, 123I, and 201Tl are produced on a regular weekly basis, and more than 1000 consignments of radiopharmaceuticals prepared from these radioisotopes are supplied to more than 30 hospitals and private practices throughout South Africa each year. Some non-medical radioisotopes are also produced.

  11. Heavy-ion versus {sup 3}He/{sup 4}He fusion-fission reactions: Angular momentum dependence of dissipation in nuclear fission

    SciTech Connect

    Ye, W.

    2011-09-15

    The stochastic Langevin model is employed to study dissipation properties in fission in the {sup 16}O + {sup 181}Ta {yields}{sup 197}Tl system by analyzing prescission neutron yields measured in this reaction. It has been found that the {sup 197}Tl nuclei undergo fission that is not in accordance with the standard Bohr-Wheeler statistical theory. A detailed comparison with previously published work in which fission excitation functions measured in {sup 3,4}He + {sup 197}Au {yields}{sup 200,201}Tl are shown to be in excellent agreement with the fission width formula predicted by the traditional models of nuclear fission suggests that nuclear dissipation strength may have an angular momentum dependence in addition to the known deformation and temperature dependence. Implications for the basic understanding of the observed abnormal rise in prescission particles at high energy and the need for further experimental confirmations are discussed.

  12. Angular momentum dependence of the nuclear level density in the A ≈170 -200 region

    NASA Astrophysics Data System (ADS)

    Gohil, M.; Roy, Pratap; Banerjee, K.; Bhattacharya, C.; Kundu, S.; Rana, T. K.; Ghosh, T. K.; Mukherjee, G.; Pandey, R.; Pai, H.; Srivastava, V.; Meena, J. K.; Banerjee, S. R.; Mukhopadhyay, S.; Pandit, D.; Pal, S.; Bhattacharya, S.

    2015-01-01

    Neutron evaporation spectra along with γ multiplicity has been measured from 201Tl*,185Re*, and 169Tm* compound nuclei at the excitation energies of ˜27 and 37 MeV. Statistical model analysis of the experimental data has been carried out to extract the value of the inverse level density parameter k at different angular-momentum (J ) regions corresponding to different γ multiplicities. It is observed that, for the present systems the value of k remains almost constant for different J . The present results for the angular-momentum dependence of the nuclear level density (NLD) parameter a ˜(=A /k ) , for nuclei with A ˜180 are quite different from those obtained in earlier measurements in the case of light- and medium-mass systems. The present study provides useful information to understand the angular-momentum dependence of the NLD at different nuclear mass regions.

  13. Measurement of relative K X-ray intensity ratio following radioactive decay and photoionization

    NASA Astrophysics Data System (ADS)

    Yalçın, P.

    2007-01-01

    The measurements of the K X-ray intensity ratio I(Kα2/Kα1), I(Kβ1/Kα1) and I(Kβ/Kα) for elements V, Mn, Zn, Tc, Ru, Cd, Xe, Ba, Cs, Hg and Rn were experimentally determined both by photon excitation, in which 59.5 keV γ-rays from a 241Am and 123.6 keV γ-rays from a 60Co were used, and following the radioactive decay of 51Cr, 55Fe, 67Ga, 99Tc, 111In, 131I, 133Ba, 133Xe, 137Cs, 201Tl and 226Ra. K X-rays emitted by samples were counted by a Si(Li) detector with resolution 160 eV at 5.9 keV. Obtained values were compared with the theoretical values. It was observed that present values agree with the previous theoretical and other experimental results.

  14. Recent development and progress of IBA cyclotrons

    NASA Astrophysics Data System (ADS)

    Kleeven, W.; Abs, M.; Delvaux, J. L.; Forton, E.; Jongen, Y.; Medeiros Romao, L.; Nactergal, B.; Nuttens, V.; Servais, T.; Vanderlinden, T.; Zaremba, S.

    2011-12-01

    Several cyclotron development projects were recently realized by Ion Beam Applications S.A. (IBA). This contribution presents three of them: (i) the intensity enhancement of the Cyclone 30 cyclotron, a machine mainly used for the production of SPECT isotopes. This project is related with the increased demand for 201Tl because of the shortage of Mo/Tc generators from nuclear reactors, (ii) development of a new versatile multiple-particle K = 30 isotope-production cyclotron (the Cyclone 30XP) being able to accelerate H -, D - and also α-particles. The α-beam of this cyclotron will allow the production of new therapeutic isotopes (e.g. 211At) and (iii) commissioning of the Cyclone 70 cyclotron installed for Arronax in France. This machine is similar to the C30XP but provides higher energy ( K = 70) and allows research on new types of medical isotopes.

  15. Heterogeneity of SPECT bull`s-eyes in normal dogs: Comparison of attenuation compensation algorithms

    SciTech Connect

    DiBella, E.V.R.; Eisner, R.L.; Schmarkey, L.S.; Barclay, A.B.; Patterson, R.E.; Nowak, D.J.; Lalush, D.S.; Tsui, B.M.W. ||

    1995-08-01

    In normal dogs, SPECT {sup 99m}Tc Sestamibi (MIBI) and {sup 201}Tl myocardial perfusion images reconstructed with filtered backprojection (FBP) show a large decrease of counts in the septal wall (S) compared to the lateral wall (L). The authors evaluated the iterative method of Chang at 0 and 1 iterations (Chang0 and Chang1), and the Maximum Likelihood-Expectation Maximization with attenuation compensation (ML-EM-ATN) algorithm on data acquired from 5 normal dogs and from simulated projection data using a homogeneous count-density model of a normal canine myocardium in the attenuation field measured in one dog. Mean counts in the S and L regions were calculated from maximum-count circumferential profile arrays. Their results demonstrate that ML-EM-ATN and Chang1 result in improved uniformity, as measured by the S/L ratio.

  16. [Estimation of I-123 metaiodobenzylguanidine (MIBG) myocardial washout].

    PubMed

    Saito, T; Watanabe, N; Saitoh, T; Asakura, T; Kanke, M; Owada, K; Hoshi, K; Kimura, K; Maruyama, Y

    1990-11-01

    A crosstalk from I-123 to Tl-201 (Tl) window was 35 +/- 30% (mean +/- SD) and 30 +/- 10% in a myocardial phantom and the images of 6 patients respectively. However, the crosstalk from Tl to I-123 was approximately 1% in each. I-123 MIBG (MIBG) and Tl myocardial SPECT images were recorded in 3 normal volunteers (N), 10 patients with myocardial infarction (MI), and 4 with dilated cardiomyopathy (DCM). The MIBG and Tl imagings were performed on the other day to avoid the crosstalk. Myocardial washout rates (WR) of Tl and MIBG were derived from 15 min and 4 hour images. WR of Tl was approximately 36% in each group. On the other hand, WR of MIBG in DCM (52 +/- 7%) and MI (41 +/- 14%) groups were statistically higher than in N (24 +/- 7%) group. Thus WR of MIBG would be useful to detect abnormalities in adrenergic nervous system.

  17. Image diagnosis of parathyroid glands in chronic renal failure

    SciTech Connect

    Takagi, H.; Tominaga, Y.; Uchida, K.; Yamada, N.; Morimoto, T.; Yasue, M.

    1983-07-01

    Twenty-two out of 31 patients with chronic renal failure and secondary hyperparathyroidism who underwent parathyroidectomy before operation underwent non-invasive image diagnosis of parathyroid glands by computed tomography (CT), scintigraphy with /sup 201/TlCl and /sup 99m/TcO/sup 4 +/, and/or ultrasonography. CT visualized 39 of 45 parathyroid glands (86.7%), weighing more than 500 mg. Scintigraphy with a subtraction method using a computer performed the diagnosis in 19 of 27 glands (70.4%). Ultrasonography detected 21 of 27 glands (77.8%). Image diagnosis was also useful in the postoperative follow-up study. The non-invasive image diagnosis of parathyroid glands in patients with chronic renal failure is thus valuable for 1) definite diagnosis of secondary hyperparathyroidism, 2) localization, and 3) diagnosis for effectiveness of conservative treatment.

  18. Atrophic nerve fibers in regions of reduced MIBG uptake in doxorubicin cardiomyopathy

    SciTech Connect

    Takano, Hajime; Ozawa Hideyuki; Kobayashi, Isao

    1995-11-01

    A myocardial MIBG-SPECT examination was conducted 2 wk after doxorubicin chemotherapy on a 52-yr-old woman without cardiac symptoms. Despite normal {sup 201}Tl scintigraphy, reduced MIBG uptake was detected in the apical anterior, inferior and lateral segments of the left ventricle. The patient died of congestive heart failure due to doxorubicin-induced cardiomyopathy 10 mo later. At necropsy, the left ventricle was markedly dilated and the apical anterior, inferior and lateral walls were thin, stiff and whitish. Nerve fibers in the apical inferior wall were atrophic and markedly fibrotic where MIBG uptake was most reduced. Nerve fibers in the septum were normal where MIBG uptake had remained normal. The histologic findings correspond with the findings on the MIBG image. MIBG imaging may detect cardiac sympathetic denervation in doxorubicin-induced cardiomyopathy before cardiac symptoms are manifest and cardiac function deteriorates. 5 refs., 2 figs.

  19. The NIST radioactivity measurement assurance program for the radiopharmaceutical industry.

    PubMed

    Cessna, Jeffrey T; Golas, Daniel B

    2012-09-01

    The National Institute of Standards and Technology (NIST) maintains a program for the establishment and dissemination of activity measurement standards in nuclear medicine. These standards are disseminated through Standard Reference Materials (SRMs), Calibration Services, radionuclide calibrator settings, and the NIST Radioactivity Measurement Assurance Program (NRMAP, formerly the NEI/NIST MAP). The MAP for the radiopharmaceutical industry is described here. Consolidated results show that, for over 3600 comparisons, 96% of the participants' results differed from that of NIST by less than 10%, with 98% being less than 20%. Individual radionuclide results are presented from 214 to 439 comparisons, per radionuclide, for (67)Ga, (90)Y, (99m)Tc, (99)Mo, (111)In, (125)I, (131)I, and (201)Tl. The percentage of participants results within 10% of NIST ranges from 88% to 98%. Published by Elsevier Ltd.

  20. The usefulness of stress tests performed in the nuclear medicine department: mathematical methods to assess efficacy at various angiographic endpoints.

    PubMed

    Hurwitz, G A; Weingert, M E; Silver, D L; MacDonald, A C; Finnie, K J; Powe, J E; Dawdy, J A

    1996-06-01

    Stress myocardial perfusion scintigraphy (SMPS) may be used to amplify or supplant information available from stress electrocardiography (ECG) in directing the clinical management of patients, including the need for coronary angiography. The apparent usefulness of SMPS may depend on referral bias, the stress mode employed and the criterion for disease. We compared markers of ischaemia on quantitative planar SMPS with 201 Tl in 503 referred patients; stress was tailored to the individual patient to include exercise (n = 154), dipyridamole (n = 118) or a combination of the two (n = 231). Four angiographic criteria of increasing severity (A-D) were targeted. The fraction of the population receiving diagnostic benefit was calculated for reversible defects (RD) or lung uptake (LU) in comparison to concurrent ST depression; abnormal baseline tracings and fixed 201Tl defects were regarded as indeterminate. Decision tree induction, a computer-learning algorithm and logistic regression were also used to assess the contribution of 13 scintigraphic and other input variables. In comparison to ST depression, RD showed incremental value in 167 (33%) patients with criterion A, decreasing to 5% with criterion D; LU showed its greatest benefit (21%) with criterion D. Both scintigraphic markers were more useful with dipyrida-mole-based tests than with exercise alone. Decision trees induced at each criterion for disease showed the predominant contribution of scintigraphic results in comparison to clinical and ECG data. In conclusion, in a referred population with a frequent requirement for pharmacological stress, the clinical utility of scintigraphy can be determined by comparison of markers of ischaemia; the results will depend, however on the angiographic criterion for disease.

  1. Sequential thallium-201 myocardial perfusion studies after successful percutaneous transluminal coronary artery angioplasty: delayed resolution of exercise-induced scintigraphic abnormalities

    SciTech Connect

    Manyari, D.E.; Knudtson, M.; Kloiber, R.; Roth, D.

    1988-01-01

    To characterize the sequential changes of myocardial perfusion scintigraphy in patients with coronary artery disease (CAD) after complete revascularization, 43 patients underwent exercise thallium-201 (/sup 201/Tl) myocardial perfusion scintigraphy before and at 9 +/- 5 days, 3.3 +/- 0.6, and 6.8 +/- 1.2 months after percutaneous transluminal coronary angioplasty (PTCA). Only patients with single-vessel CAD, without previous myocardial infarction, and without evidence of restenosis at 6 to 9 months after PTCA were included. Perfusion scans were analyzed blindly with the use of a new quantitative method to define regional myocardial perfusion in the topographic distribution of each coronary artery, which was shown to be reproducible (r = .94 or higher and SEE of 7% or less, between repeated measures by one and two operators). At 4 to 18 days after PTCA, the mean treadmill walking time increased by 123 +/- 42 sec, mean exercise-induced ST segment depression decreased by 0.6 +/- 0.3 mm, group maximal heart rate increased by 20 +/- 9 beats/min, and group systolic blood pressure at peak exercise increased by 24 +/- 10 mm Hg, compared with pre-PTCA values (p less than .001). However, no group differences were noted in these variables between the three post-PTCA stages. Myocardial perfusion in the distribution of the affected (dilated) coronary artery, on the other hand, improved progressively. In the 45 degree left anterior oblique view for instance, myocardial perfusion increased at 9 days after PTCA (from 68 +/- 24% before PTCA to 91 +/- 9%, p less than .001) and at 3.3 months after PTCA (101 +/- 8%, p less than .05 vs 9 days after PTCA), but no further significant changes were seen at 6.8 months after PTCA (102 +/- 8%). Similar changes were noted in the other two views. No relationship between minor complications during PTCA and delayed improvement on the /sup 201/Tl was observed.

  2. Verapamil prevents silent myocardial perfusion abnormalities during exercise in asymptomatic patients with hypertrophic cardiomyopathy

    SciTech Connect

    Udelson, J.E.; Bonow, R.O.; O'Gara, P.T.; Maron, B.J.; Van Lingen, A.; Bacharach, S.L.; Epstein, S.E.

    1989-05-01

    Recent studies indicate that reversible 201Tl perfusion defects, compatible with silent myocardial ischemia, commonly develop during exercise in asymptomatic or mildly symptomatic patients with hypertrophic cardiomyopathy (HCM). To determine whether this represents a dynamic process that may be modified favorably by medical therapy, we studied 29 asymptomatic or minimally symptomatic patients with HCM, aged 12-55 years (mean, 28), with exercise 201Tl emission computed tomography under control conditions and again after 1 week of oral verapamil (mean dosage, 453 mg/day). Treadmill time increased slightly during verapamil (21.0 +/- 3.6 to 21.9 +/- 2.7 minutes, p less than 0.005), but peak heart rate-blood pressure product was unchanged (26.3 +/- 6.0 X 10(3)) compared with 25.0 +/- 6.4 X 10(3). Two midventricular short-axis images per study were divided into five regions each, and each of these 10 regions was then analyzed on a 0-2 scale by three observers blinded with regard to the patients' therapy. Average regional scores of 1.5 or less were considered to represent perfusion defects, and a change in regional score of 0.5 or more was considered to constitute a significant change. During control studies, 15 patients (52%) developed perfusion defects with exercise (average, 3.7 regions per patient). In 14 of these patients, all perfusion defects completely reversed after 3 hours of rest; one patient had fixed defects. After administration of verapamil, exercise perfusion scores improved in 10 of the 14 patients (71%) with reversible defects; there was overall improvement in 34 of 50 (68%) regions with initially reversible perfusion defects.

  3. Characteristics of single- and dual-photopeak energy window acquisitions with thallium-201 IQ-SPECT/CT system.

    PubMed

    Shibutani, Takayuki; Onoguchi, Masahisa; Yoneyama, Hiroto; Konishi, Takahiro; Matsuo, Shinro; Nakajima, Kenichi; Kinuya, Seigo

    2017-08-01

    Although dual-energy (DE) acquisition with conventional (201)Tl myocardial perfusion SPECT has several advantages such as improved attenuation of the inferior wall and increased acquisition counts, the characteristics of IQ-SPECT have not been fully evaluated. We evaluate the difference of characteristics between single-energy (SE) and dual-energy (DE) imaging using (201)Tl myocardial IQ-SPECT. Two myocardial phantoms were created simulating normal myocardium and infarction of the inferior wall. Energy windows were set at 70 keV ± 10% for SE, and an additional 167 keV ± 7.5% for DE. SPECT images were reconstructed using the ordered subset conjugates gradient minimizer (OSCGM) method. We visually and quantitatively compared short-axis images of correction for no (NC), for attenuation (AC) or for both AC and scatter (ACSC) images. The average counts of SE and DE projection data were 17.5 and 20.3 counts/pixel, respectively. The DE data increased acquisition counts by approximately 16% compared with the SE data. The average visual score of normal myocardium did not differ significantly between the SE and DE images. However, the DE image of defective myocardium showed a significantly lower score in AC than SE images. The % uptake values of DE image with both NC and AC were significantly higher than those of SE images. The DE images of the inferior defective areas (segments 4 and 10) showed approximately 5-10% higher uptake compared with the SE images. The DE image with NC improved attenuation of the inferior wall. However, DE image with AC showed low defect detectability. Thus, AC should be used with SE rather than DE. Furthermore, while the SE image with ACSC can be used to detect perfusion defects, it must be interpreted carefully including the possibility of artificial inhomogeneity even in the normal myocardium.

  4. Effect of hypoxia on thallium kinetics in cultured chick myocardial cells

    SciTech Connect

    Friedman, B.J.; Beihn, R.; Friedman, J.P.

    1987-09-01

    To assess the effect of hypoxia on cellular thallium-201 (/sup 201/Tl) uptake and washout independent of coronary flow, we studied thallium kinetics during normoxia and hypoxia in cultured chick ventricular cells. Monolayers of contracting ventricular cells grown on coverslips were placed in a chamber and perfused to asymptote with media containing /sup 201/Tl. Perfusates were equilibrated with 5% CO/sub 2/-95% air or 5% CO/sub 2/-95% nitrogen for normoxia and hypoxia, respectively. Washout thallium kinetics were then observed during perfusion with unlabeled media. Twenty paired experiments were performed, randomly alternating the sequence of normoxia and hypoxia. Pharmacokinetics for thallium were determined by computer using standard formulae. Thallium uptake and washout were best described by assuming that intracellular thallium was contained within a single compartment. Cellular thallium uptake, as well as transfer rate constants for thallium uptake and for thallium washout during normoxia and hypoxia, were compared using paired t-tests. During normoxia and hypoxia, respectively, thallium uptake was 22 +/- 7% and 19 +/- 7% of asymptote (p less than 0.01); the compartmental rate constant for uptake by the cell was 0.16 +/- 0.07 min-1 and 0.15 +/- 0.06 min-1 (N.S.); and the transfer rate constant for washout from the cell was 0.26 +/- 0.06 min-1 and 0.23 +/- 0.05 min-1 (p less than 0.01). We conclude that there was a small (14%) decrease in thallium uptake during hypoxia. The rate of thallium uptake and washout was slightly less during hypoxia, although only the rate of washout was significantly less. These data show that cellular accumulation of thallium and the rate of washout of thallium were minimally decreased by hypoxia independent of blood flow.

  5. Noninvasive targeted imaging of matrix metalloproteinase activation in a murine model of postinfarction remodeling.

    PubMed

    Su, Haili; Spinale, Francis G; Dobrucki, Lawrence W; Song, James; Hua, Jing; Sweterlitsch, Sarah; Dione, Donald P; Cavaliere, Patti; Chow, Conroy; Bourke, Brian N; Hu, Xiao-Yu; Azure, Michael; Yalamanchili, Padmaja; Liu, Richard; Cheesman, Edward H; Robinson, Simon; Edwards, D Scott; Sinusas, Albert J

    2005-11-15

    Time-dependent activation of matrix metalloproteinases (MMPs) after myocardial infarction (MI) contributes to adverse left ventricular (LV) remodeling; however, noninvasive methods to monitor this process serially are needed. MMP-targeted radiotracers were developed that displayed selective binding kinetics to the active MMP catalytic domain. Initial nonimaging studies were performed with a (111)In-labeled MMP-targeted radiotracer ((111)In-RP782) and negative control compound ((111)In-RP788) in control mice (Ctrl) and in mice 1 week after surgically induced MI. Localization of (111)In-RP782 was demonstrated within the MI by microautoradiography. A 334+/-44% increase (P<0.001 versus Ctrl) in relative retention of (111)In-RP782 was confirmed by gamma well counting of myocardium. Subsequent high-resolution dual-isotope planar and hybrid micro-single-photon emission computed tomography/CT imaging studies with an analogous 99mTc-labeled MMP-targeted radiotracer (99mTc-RP805) and 201Tl demonstrated favorable biodistribution and clearance kinetics of 99mTc-RP805 for in vivo cardiac imaging, with robust retention 1 to 3 weeks after MI in regions of decreased 201Tl perfusion. Gamma well counting yielded a similar approximately 300% increase in relative myocardial retention of 99mTc-RP805 in MI regions (Ctrl, 102+/-9%; 1 week, 351+/-77%; 2 weeks, 291+/-45%; 3 weeks, 292+/-41%; P<0.05 versus Ctrl). Myocardial uptake in the MI region was also significantly increased approximately 5-fold when expressed as percentage injected dose per gram tissue. There was also a significant 2-fold increase in myocardial activity in remote regions relative to control mice, suggesting activation of MMPs in regions remote from the MI. This novel noninvasive targeted MMP radiotracer imaging approach holds significant diagnostic potential for in vivo localization of MMP activation and tracking of MMP-mediated post-MI remodeling.

  6. Effects of coronary angioplasty and reperfusion on distribution of myocardial flow

    SciTech Connect

    Wahr, D.W.; Ports, T.A.; Botvinick, E.H.; Dae, M.; Schechtmann, N.; Huberty, J.; Hattner, R.S.; O'Connell, J.W.; Turley, K.

    1985-08-01

    To assess the effects of angioplasty (PTCA) and intracoronary streptokinase (ICSK) on relative myocardial perfusion, the authors administered /sup 99m/Tc-macroaggregated albumin (MAA) to the uninvolved coronary artery before successful PTCA in 33 patients and before successful infusion of ICSK in eight patients and of /sup 111/In-MAA into the same vessel after the intervention. In 10 patients who underwent PTCA, MAA was injected into the involved, instrumented coronary artery. Computer-processed images were acquired in registry and compared. Similar scintigraphic studies were performed in six control patients and in 11 in whom planned interventions were not performed or were unsuccessful. Distribution of MAA was also compared with angiographic results and with the distribution of /sup 201/Tl on images obtained in patients at rest or on redistribution images obtained before and soon after intervention in 22 patients. In control patients and those studied after aborted or unsuccessful intervention, scintigraphic results showed excellent correlation with the angiographic anatomy and were without serial change. When MAA was injected into the uninvolved vessel, the scintigram revealed evidence of collateral perfusion with retraction of the perfusion zone from that of the involved coronary in 19 of 33 patients undergoing PTCA and in three of eight of those receiving ICSK. When MAA was injected into the involved artery, a relative increase in perfusion was seen in eight of 10 patients after PTCA. Although 30 patients demonstrated scintigraphic evidence of collateral vessels, only 10 patients had angiographic evidence of collateral circulation before intervention. The distribution of /sup 201/Tl demonstrated little change in its global pattern and regions previously supplied by collaterals were generally well perfused after intervention.

  7. Pure right ventricular infarction.

    PubMed

    Inoue, Katsuji; Matsuoka, Hiroshi; Kawakami, Hideo; Koyama, Yasushi; Nishimura, Kazuhisa; Ito, Taketoshi

    2002-02-01

    A 76-year-old man with chest pain was admitted to hospital where electrocardiography (ECG) showed ST-segment elevation in leads V1-4, indicative of acute anterior myocardial infarction. ST-segment elevation was also present in the right precordial leads V4R-6R. Emergency coronary angiography revealed that the left coronary artery was dominant and did not have significant stenosis. Aortography showed ostial occlusion of the right coronary artery (RCA). Left ventriculography showed normal function and right ventriculography showed a dilated right ventricle and severe hypokinesis of the right ventricular free wall. Conservative treatment was selected because the patient's symptoms soon ameliorated and his hemodynamics was stable. 99mTc-pyrophosphate and 201Tl dual single-photon emission computed tomography showed uptake of 99mTc-pyrophosphate in only the right ventricular free wall, but no uptake of 99mTc-pyrophosphate and no perfusion defect of 201Tl in the left ventricle. The peak creatine kinase (CK) and CK-MB were 1,381 IU/L and 127 IU/L, respectively. His natural course was favorable and the chest pain disappeared under medication. Two months after the onset, the ECG showed poor R progression in leads V1-4 indicating an old anterior infarction. Coronary angiography confirmed the ostial stenosis of the hypoplastic RCA. This was a case of pure right ventricular free wall infarction because of the occlusion of the ostium of the hypoplastic RCA, but not of the right ventricular branch. Because the electrocardiographic findings resemble those of an acute anterior infarction, it is important to consider pure right ventricular infarction in the differential diagnosis.

  8. Detection of residual jeopardized myocardium 3 weeks after myocardial infarction by exercise testing with thallium-201 mycardial scintigraphy

    SciTech Connect

    Turner, J.D.; Schwartz, K.M.; Logic, J.R.; Sheffield, L.T.; Kansal, S.; Roitman, D.I.; Mantle, J.A.; Russell, R.O.; Rackley, C.E.; Rogers, W.J.

    1980-04-01

    The usefulness of thallium-201 (Tl-201) exercise myocardial scintigraphy in identifying patients with multivessel coronary artery disease (MVCAD) and residual jeopardized myocardium after myocardial infarction (MI) was evaluated in 32 patients 3 weeks after MI. All patients underwent (1) limited multilead submaximal treadmill testing, (2) thallium-201 (Tl) myocardial scintigraphy at end-exercise and at rest, and (3) coronary and left ventricular angiography. Tl-201 perfusion defects were categorized as either reversible (ischemia) or irreversible (scar). The conventional exercise test was designated positive if there was ST depression > = 1mm and/or angina. Jeopardized myocardium (JEP) was defined angiographically as a segment of myocardium with normal or hypokinetic wall motion supplied by a significantly stenotic major coronary artery. MVCAD was defined as two or more significantly stenotic coronary arteries. Significant coronary stenosis was categorized as either 50 to 69% diameter narrowing or > = 70% diameter narrowing, thereby yielding, respectively, two subgroups each of jeopardized myocardium (JEP-50 and JEP-70) and MVCAD (MV-50 and MV-70). Clinical findings of angina, heart failure or ventricular arrhythmias during the late convalescent period after MI occurred in four of 10 patients (40%) with MV-50, five of 16 (31%) with MV-70, four of 10 (40%) with JEP-50 and five of 18 (28%) with JEP-70, and thus were insensitive for detecting MVCAD and JEP. Reversible ischemia and/or a positive conventional exercise test occurred in five of 10 patients (50%) with MV-50, 13 of 16 (81%) with MV-70, four of 10 (40%) with JEP-50 and 15 of 18 (83%) with JEP-70. All eight patients with both Tl-201 reversible ischemia and a positive conventional exercise test had JEP-70. In 30 of 31 patients (97%) with angiographic asynergy, Tl-201 scar was detected. No complications were associated with exercise testing.

  9. A study on quantitative analysis of exposure dose caused by patient depending on time and distance in nuclear medicine examination

    NASA Astrophysics Data System (ADS)

    Kim, H. S.; Cho, J. H.; Shin, S. G.; Dong, K. R.; Chung, W. K.; Chung, J. E.

    2013-01-01

    This study evaluated possible actions that can help protect against and reduce radiation exposure by measuring the exposure dose for each type of isotope that is used frequently in nuclear medicine before performing numerical analysis of the effective half-life based on the measurement results. From July to August in 2010, the study targeted 10, 6 and 5 people who underwent an 18F-FDG (fludeoxyglucose) positron emission tomography (PET) scan, 99mTc-HDP bone scan, and 201Tl myocardial single-photon emission computed tomography (SPECT) scan, respectively, in the nuclear medicine department. After injecting the required medicine into the subjects, a survey meter was used to measure the dose depending on the distance from the heart and time elapsed. For the 18F-FDG PET scan, the dose decreased by approximately 66% at 90 min compared to that immediately after the injection and by 78% at a distance of 1 m compared to that at 0.3 m. In the 99mTc-HDP bone scan, the dose decreased by approximately 71% in 200 min compared to that immediately after the injection and by approximately 78% at a distance of 1 m compared to that at 0.3 m. In the 201Tl myocardial SPECT scan, the dose decreased by approximately 30% in 250 min compared to that immediately after the injection and by approximately 55% at a distance of 1 m compared to that at 0.3 m. In conclusion, the dose decreases by a large margin depending on the distance and time. In conclusion, this study measured the exposure doses by isotopes, distance from the heart and exposure time, and found that the doses were reduced significantly according the distance and the time.

  10. Intramyocardial sustained delivery of basic fibroblast growth factor improves angiogenesis and ventricular function in a rat infarct model.

    PubMed

    Iwakura, Atsushi; Fujita, Masatoshi; Kataoka, Kazuaki; Tambara, Keiichi; Sakakibara, Yutaka; Komeda, Masashi; Tabata, Yasuhiko

    2003-05-01

    Recently we have demonstrated that the release of basic fibroblast growth factor (bFGF) from a biodegradable gelatin hydrogel carrier depends on the degradation of hydrogel in vivo. The purpose of our study was to assess whether bFGF-incorporating gelatin hydrogels induce myocardial angiogenesis and improve left ventricular function in the infarcted myocardium of rats. Studies were conducted in 22 Lewis rats after a 4-week ligation of the proximal left anterior descending coronary artery. The rats were randomized into the following two groups: the control group (n = 11) had an intramyocardial injection of saline alone, and the FGF group (n = 11) had gelatin hydrogel microspheres containing 100 microg of bFGF injected into the border zone of the infarct area after the repeat left thoracotomy. For visualization of the regional myocardial blood flow in the rat heart, (201)Tl images were taken just before and 4 weeks after the treatment using a 4-head single photon emission computed tomography scanner with pinhole collimators. Left ventricular function was also assessed with echocardiography and a micromanometer-tipped catheter. Finally, the extent of myocardial angiogenesis was evaluated quantitatively in the postmortem analysis. The (201)Tl defect score in the control group remained unchanged before and after the treatment, whereas it decreased significantly in the FGF group. Both regional and global left ventricular function was significantly better in the FGF group compared with the control group. The vascular density in the border zone of the infarct in the FGF group was significantly higher than that in the control group. In conclusion, intramyocardial injection of bFGF-impregnated gelatin hydrogels induces functionally significant angiogenesis and improves left ventricular systolic and diastolic function in the infarcted myocardium of rats.

  11. [Dobutamine stress body surface mapping in Kawasaki disease].

    PubMed

    Seki, T; Zhang, J; Ogawa, S; Hirayama, T

    1994-11-01

    The dobutamine (DOB) stress body surface mapping tests were carried out to detect myocardial ischemia in 23 patients who had Kawasaki disease previously. Eight of 23 patients (group A) had coronary stenosis of 75% or more diameter reduction in major coronary arteries without sufficient collateral flow, as shown by the coronary angiography, but without myocardial infarction. Nine patients (group B) showed no ischemic change exercised 201Tl myocardial scintigram. Six patients (group C) had myocardial infarction due to Kawasaki disease. ST segment potential mapping (0.04 sec after the J point in QRS) and ST-T Isointegral mapping were performed using CVM-3000 system (87 leads), and the following calculations were made: number of leads with horizontal or down-sloping ST depression of 0.10 mV or more, lasting 0.08 sec (nST); row number of the minimum lead in the Isointegral map (Imin); number of positive leads on the seventh row in Isointegral mapping (I-7); number of positive leads on the first row in Isointegral mapping (I-1) and I-7/I-1 ratio. Based on these calculations the criteria for detecting myocardial ischemia (nST < or = 2, Imin < or = 2, I-7/I-1 > or = 1) were created and their usefulness was tested using findings of coronary angiography and exercised 201Tl myocardial scintigram as the golden standard. For the diagnosis of ischemic lesion, the DOB stress body surface mapping test in group A had higher specificity (nST: 100%, Imin: 89%, I-7/I-1: 100% vs. 78%) and higher sensitivity (75%, 50%, 63% vs. 38%), than those by the Treadmill test, while ischemic changes were not detected in group C by this test. From these results it is concluded that it is useful in evaluating ischemic heart disease in children who can not perform Treadmill exercised test adequately.

  12. Establishing the Empirical Relationship Between Non-Science Majoring Undergraduate Learners' Spatial Thinking Skills and Their Conceptual Astronomy Knowledge. (Spanish Title: Estableciendo Una Relación Empírica Entre el Razonamiento Espacial de los Estudiantes de Graduación de Carreras no Científicas y su Conocimento Conceptual de la Astronomía.) Estabelecendo Uma Relação Empírica Entre o RacioCínio Espacial dos Estudantes de Graduação EM Carreiras Não Científicas e Seu Conhecimento Conceitual da Astronomia

    NASA Astrophysics Data System (ADS)

    Heyer, Inge; Slater, Stephanie J.; Slater, Timothy F.

    2013-12-01

    The astronomy education community has tacitly assumed that learning astronomy is a conceptual domain resting upon spatial thinking skills. As a first step to formally identify an empirical relationship, undergraduate students in a non-major introductory astronomy survey class at a mediumsized, Ph.D. granting, mid-western US university were given pre- and post-astronomy conceptual diagnostics and spatial reasoning diagnostics, Instruments used were the "Test Of Astronomy Standards" and "What Do You Know?" Using only fully matched data for analysis, our sample consisted of 86 undergraduate non-science majors. Students' normalized gains for astronomy surveys were low at .26 and .13 respectively. Students' spatial thinking was measured using an instrument designed specifically for this study. Correlations between the astronomy instruments' pre- to post-course gain scores and the spatial assessment instrument show moderate to strong relationships suggesting the relationship between spatial reasoning and astronomy ability can explain about 25% of the variation in student achievement. La comunidad de educación en astronomía ha supuesto de forma tácita que el aprendizaje de la astronomía consiste en un dominio conceptual fundamentado en el razonamiento espacial. Como un primer paso para identificar formalmente una relación empírica entre estas dos cosas, utilizamos como muestra los estudantes de graduación de carreras no científicas de un curso experimental en una universidad norteamericana del medioeste de porte mediano con programa de Doctorado em curso, en el cual estos estudiantes se sometieron a un diagnóstico de razonamiento espacial y conceptos astronómicos antes e después del mismo. Las herramientas utilizadas fueron el Test Of Astronomy Standards (TOAST) y el cuestionario What do you know? Utilizando solo los datos completamente consistentes para este análisis, nuestra muestra consistió en 86 estudantes de graduación. Las mejoras, depués de

  13. Apparent Motion of the Sun, Shadows of Objects and Measurement of Time in the View of Seventh Grade Students of Middle School. (Breton Title: Movimento Aparente do Sol, Sombras dos Objetos e Medição do Tempo na Visão de Alunos do Sétimo Ano do Ensino Fundamental.) Movimiento Aparente del Sol, Sombras de los Objetos y Medición del Tiempo en la Visión de Estudiantes del Séptimo Grado del Ciclo Pirmario

    NASA Astrophysics Data System (ADS)

    Iria Machado, Daniel

    2013-07-01

    The apparent motion of the Sun on the celestial sphere and the behavior of the shadows of objects over time are observable phenomena in everyday life. However, students often do not have a proper understanding of such occurrences, and can even display misconceptions about them. Therefore, we performed a research in order to know students' notions about these subjects and to evaluate the contribution to their understanding brought about by an activity performed with an interactive sundial in an informal learning environment. We investigated the ideas of 43 students from the seventh grade of middle school by applying a test with open questions before and after an activity with an analemmatic sundial, conducted by a monitor. A significant proportion of students were initially unaware of most of the phenomena treated. The intervention performed helped the students to assimilate new concepts, providing the contact with new phenomena and to a lesser degree, the development of explanations about them, indicating an educational potential of this action. However, the contribution to the understanding of some of the ideas explored was small, pointing to the need to make additional observations, studies and discussions. O movimento aparente do Sol na esfera celeste e o comportamento das sombras dos objetos com o passar do tempo são fenômenos observáveis no dia a dia. No entanto, muitas vezes os estudantes não possuem uma compreensão adequada de tais ocorrências, podendo inclusive exibir concepções alternativas a seu respeito. Por isso, efetuou-se uma pesquisa com o intuito de conhecer as noções dos alunos sobre esses temas e avaliar a contribuição para seu entendimento propiciada por uma atividade feita com um relógio de Sol interativo, em um ambiente de ensino informal. Foram investigadas as ideias de 43 alunos do sétimo ano do Ensino Fundamental mediante a aplicação de um teste com questões abertas antes e depois de uma atividade com um relógio de Sol

  14. Nuclear myocardial perfusion imaging using thallium-201 with a novel multifocal collimator SPECT/CT: IQ-SPECT versus conventional protocols in normal subjects.

    PubMed

    Matsuo, Shinro; Nakajima, Kenichi; Onoguchi, Masahisa; Wakabayash, Hiroshi; Okuda, Koichi; Kinuya, Seigo

    2015-06-01

    A novel multifocal collimator, IQ-SPECT (Siemens) consists of SMARTZOOM, cardio-centric and 3D iterative SPECT reconstruction and makes it possible to perform MPI scans in a short time. The aims are to delineate the normal uptake in thallium-201 ((201)Tl) SPECT in each acquisition method and to compare the distribution between new and conventional protocol, especially in patients with normal imaging. Forty patients (eight women, mean age of 75 years) who underwent myocardial perfusion imaging were included in the study. All patients underwent one-day protocol perfusion scan after an adenosine-stress test and at rest after administering (201)Tl and showed normal results. Acquisition was performed on a Symbia T6 equipped with a conventional dual-headed gamma camera system (Siemens ECAM) and with a multifocal SMARTZOOM collimator. Imaging was performed with a conventional system followed by IQ-SPECT/computed tomography (CT). Reconstruction was performed with or without X-ray CT-derived attenuation correction (AC). Two nuclear physicians blinded to clinical information interpreted all myocardial perfusion images. A semi-quantitative myocardial perfusion was analyzed by a 17-segment model with a 5-point visual scoring. The uptake of each segment was measured and left ventricular functions were analyzed by QPS software. IQ-SPECT provided good or excellent image quality. The quality of IQ-SPECT images without AC was similar to those of conventional LEHR study. Mid-inferior defect score (0.3 ± 0.5) in the conventional LEHR study was increased significantly in IQ-SPECT with AC (0 ± 0). IQ-SPECT with AC improved the mid-inferior decreased perfusion shown in conventional images. The apical tracer count in IQ-SPECT with AC was decreased compared to that in LEHR (0.1 ± 0.3 vs. 0.5 ± 0.7, p < 0.05). The left ventricular ejection fraction from IQ-SPECT was significantly higher than that from the LEHR collimator (p = 0.0009). The images of IQ-SPECT acquired in a

  15. Use of elephant grass for energy production in Campos dos Goytacazes-RJ, Brazil.

    PubMed

    Daher, R F; Souza, L B; Gravina, G A; Machado, J C; Ramos, H C C; Silva, V Q R; Menezes, B R S; Schneider, L S A; Oliveira, M L F; Gottardo, R D

    2014-12-19

    Elephant grass is a tropical forage plant widely distributed throughout Brazil. It was first exclusively used in the livestock sector as cattle feed. The grass is characterized by its high productivity and photosynthetic capacity and is considered as an alternative source of renewable energy. Here, we estimated the general combining ability of the parents and specific combining ability of the hybrids based on morpho-agronomic biomass-quality traits. The experiment was conducted in a randomized block design with 3 replicates. The diallel was composed of 16 hybrids and 2 groups of genitors. In the diallel analysis of variance, we observed a significant difference among treatments. A significant difference was observed among genitors for dry matter production (DMP). For the general combining ability of group 1, the traits leaf blade width, DMP, height, percentage of neutral detergent fiber, percentage of hemicellulose, percentage of lignin, percentage of acid detergent fiber, and percentage of cellulose were significant. For the estimates of general combining ability of DMP, parents Porto Rico 534-B, Vruckwona, Taiwan A-146, and Mercker S. E. A. were 0.4748, 3.2819, 1.1659, and 0.4317. The parents of Mercker S. E. A. and Porto Rico 534-B produced the highest percentage of detergent fiber and percentage of lignin with values of 0.1482 and 0.0856. Thus, parents Vruckwona, Porto Rico 534-B, and Taiwan A-146 are promising for integration into breeding programs. The best hybrid combinations for DMP were 1 x 5, 1 x 8, 2 x 6, 3 x 7, and 4 x 5.

  16. The Politics of Hispanic Education. Un Paso pa'lante y dos pa'tras.

    ERIC Educational Resources Information Center

    Meier, Kenneth J.; Stewart, Joseph, Jr.

    This book presents an in-depth examination of 142 U.S. school districts (containing at least 5,000 students and 5 percent Hispanic enrollment) in order to understand Hispanic inequities in education and what can be done to correct these inequities. Chapter 1 presents political theory of educational policy. Chapter 2 presents an overview of the…

  17. One? "Dos" Drei. A Study of Code Switching in Child Trilingualism

    ERIC Educational Resources Information Center

    Davidiak, Elena

    2010-01-01

    This longitudinal study focuses on the language production of two siblings, aged 6 and 9 at the beginning of the data collection period, who have been brought up in a bilingual family in New York. The parents of the two girls are native speakers of German and Spanish, respectively, and English for them is the language of education and the larger…

  18. Ensuring the relocatability of programs in the operational system DOS YeS

    NASA Technical Reports Server (NTRS)

    Novoseltsev, S. K.; Orlov, I. G.; Chesalin, A. S.

    1979-01-01

    Specific modifications in the Disk Operational System Unified Series to insure the relocatability of programs stored permanently in the core image library is described. A self-relocating method for loading programs into the working memory with re-editing all the programs recorded in the core image library is presented. The modified linkage editor can be included in a relocation dictionary containing data about each address constant at the assembly stage at the request of the programmer. The relocation dictionary increases the dimension of the RL-phase in comparison with the dimension of this same phase when edited by the standard method, making possible the creation of multiphase program complexes. Generation and use of the modified system using Assembly language is described. An example of the use of the system is given, and limitations of the use of the relocatable programs in the modified system are outlined.

  19. Dos and Donts for Conditional Acceptance of Nonconforming Supplies or Services

    DTIC Science & Technology

    2016-06-01

    have quite a few options in dealing with this prob-lem, including conditional acceptance. The purpose of this article is, first, to share a personal ...accom- modate that request. Out of all the choices (reject, rework at no additional cost, replacement or terminate for default) avail- able under FAR...sub-part 46.407 to the government, conditional acceptance was probably thought to be the easiest and most expeditious choice . But for whom

  20. Denoised ordered subset statistically penalized algebraic reconstruction technique (DOS-SPART) in digital breast tomosynthesis

    NASA Astrophysics Data System (ADS)

    Garrett, John; Li, Yinsheng; Li, Ke; Chen, Guang-Hong

    2017-03-01

    Digital breast tomosynthesis (DBT) is a three dimensional (3D) breast imaging modality in which projections are acquired over a limited angular span around the compressed breast and reconstructed into image slices parallel to the detector. DBT has been shown to help alleviate the breast tissue overlapping issues of two dimensional (2D) mammography. Since the overlapping tissues may simulate cancer masses or obscure true cancers, this improvement is critically important for improved breast cancer screening and diagnosis. In this work, a model-based image reconstruction method is presented to show that spatial resolution in DBT volumes can be maintained while dose is reduced using the presented method when compared to that of a state-of-the-art commercial reconstruction technique. Spatial resolution was measured in phantom images and subjectively in a clinical dataset. Noise characteristics were explored in a cadaver study. In both the quantitative and subjective results the image sharpness was maintained and overall image quality was maintained at reduced doses when the model-based iterative reconstruction was used to reconstruct the volumes.