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J L Moretti

Publications and source records attributed to J L Moretti.

124 records · Page 7Linked to original sources
PubMedDate not supplied

Effects of dipyridamole on left ventricular function.

BACKGROUND: Changes induced by dipyridamole infusion on left ventricular function in healthy individuals have not been investigated by gated myocardial perfusion single photon emission computed tomographic (SPECT) imaging. METHODS AND RESULTS: This study examined the amplitude and duration of changes induced by dipyridamole infusion on left ventricular function as assessed by technetium 99m sestamibi gated SPECT in 18 subjects with a low likelihood of coronary artery disease. Twenty mCi (740 MBq) of Tc-99m sestamibi were injected at rest. Three different consecutive gated SPECT images were performed 60 minutes later: baseline at rest, during the infusion of 0.76 mg/kg of dipyridamole, and 1 hour later. No patient received aminophylline. Left ventricular ejection fraction (LVEF), end-diastolic volume, and end-systolic volume were automically computed. Heart rate (HR) and blood pressure were regularly monitored. Mean LVEF was 63.2% +/- 8.0% baseline at rest, increased to 73.8% +/- 8.2% (P = .0001) during dipyridamole infusion, and returned to baseline values (63.0% +/- 7.5%) 1 hour later. End-diastolic volume did not vary significantly, and end-systolic volume decreased (from 32.2 +/- 19.5 to 26.6 +/- 17.9 u, P = .002) and returned to baseline values (32.7 +/- 15.6 u) 1 hour later. Dipyridamole induced moderate HR acceleration (from 80.2 +/- 15.0 to 96.5 +/- 9.6 beats/min, P < .001) and a slight decrease in diastolic blood pressure (from 80.6 +/- 8.1 to 70.1 +/- 9.0 mm Hg, P < .001). However, 1 hour later, HR and blood pressure had returned to baseline values. CONCLUSIONS: Dipyridamole increases LVEF and HR and decreases diastolic blood pressure slightly in healthy individuals. Because dipyridamole gated SPECT imaging acquisition is usually started 60 minutes after dipyridamole infusion, LVEF is in fact estimated at rest.

Adult↗
PubMedDate not supplied

Fetal pulmonary artery Doppler waveform: a preliminary report.

OBJECTIVE: The study of fetal lung circulation by means of pulmonary Doppler investigation. METHODS: Pulmonary Doppler ultrasound obtained with color pulsed-Doppler with a 3.5- to 5-MHz probe. Measure of resistance index and pulsatility index. PATIENTS: 47 pregnant women with singleton, between 18 and 39.5 weeks of gestation, were recruited to have pulmonary Doppler ultrasound. Seven fetuses had intrauterine fetal growth retardation (IUGR). Overall, 50 Doppler velocity waveforms were measured. RESULTS: Resistance and pulsatility index were measured in all patients and at each examination. Resistance index (0.86 +/- 0.03) and pulsatility index (2.46 +/- 0.34) were found to be stable during pregnancy. Pulmonary pulsatility index in IUGR fetuses (2.71 +/- 0.33) were found to be higher than those in normotrophic infants (p = 0.006), whereas no difference was found in resistance index between the same subgroups. Moreover, no difference was found in pulsatility index measurements between preterm small-for-gestational age fetuses and normotrophic fetuses measured between 36 and 39.5 weeks of gestation (2.68 +/- 0.31 vs. 2.49 +/- 0.28). CONCLUSION: Pulmonary resistance index is not statistically different between normotrophic and IUGR fetuses. In contrast, pulmonary pulsatility index is significantly higher in IUGR fetuses when compared to normotrophic fetuses. Pulmonary Doppler ultrasound should be evaluated in a larger trial and correlation between Doppler measurements and fetal lung maturation should be studied.

Female↗
PubMedDate not supplied

Pharmacokinetics of intravenously administered 125I-labelled human alpha 1-acid glycoprotein.

The volumes of distribution of many acidic drugs have been shown to be close to that of their binding protein, i.e. serum albumin. The distribution of basic drugs mainly bound to alpha 1-acid glycoprotein (AAG) can be questioned with respect to its dependency upon the distribution of this plasma protein. So, a pharmacokinetic study was performed in 7 subjects with human 125I-labelled alpha 1-acid glycoprotein. The steady-state volume of distribution was found to be 5.37 +/- 0.82L. The central volume was 3.23 +/- 0.33L, close to that of plasma volume and the peripheral volume was 2.14 +/- 0.63L. These data allowed the establishment of an equation giving access to the volume of distribution of a basic drug by relating its unbound fraction to physiological distribution of alpha 1-acid glycoprotein. The values yielded by this equation show that the actual and calculated volumes of distribution of basic drugs mainly bound to AAG are discrepant. This protein is thus not the main factor controlling the distribution of basic drugs within the body.

Adult↗
PubMedDate not supplied

Breast carcinoma cell uptake and biodistribution of technetium-99m-carboxymethyl benzylamide dextran.

Carboxymethyl Benzylamide Dextran (CMDB7) displayed an in vitro growth inhibitory activity on breast tumor cells. CMDB7 is able to disrupt the interaction of angiogenic growth factors (FGF2, TGF beta and PDGF) with their membrane receptors. This compound blocks the angiogenesis of MDA-MB435 carcinoma xenografted in mammary fat pad and their lung metastases in nude mice. In this work, we studied the uptake of CMDB7 labeled with 99mTc in cultured human breast cancer MCF-7 cell line and the highly tumorigenic MCF-7ras cell line (Ha-ras-transfected MCF-7 cells) and the in vivo distribution in MCF-7ras tumor-bearing mice. The 99mTc-CMDB7 are stable and the intracellular concentration is time-dependent and reaches a plateau at 180 minutes. 99mTc CMDB7 uptake is much higher in MCF-7ras cells than MCF-7 cells. Since CMDB7 is internalized and could also inhibit cell proliferation by acting at nuclear sites, we investigated the MCF-7ras nuclear localization after cell fractionation. Cell fractionation revealed a cytoplasmic and nuclear internalization of CMDB7. The tumor uptakes of 99mTc-CMDB7 were 0.34%, 0.72% and 0.62% of the administrated doses per gram of tumor tissue at 1 hour, 3 hour and 5 hours respectively after their injection. The blood clearance of 99mTc CMDB7 was very rapid and the liver, spleen and kidney uptakes were very weak. These results confirm the absence of toxicity of CMDB7 and the usefulness of CMDB7 in cancer therapy by targeting breast tumors.

Animals↗
PubMedDate not supplied

[Study of circulation of cerebro-spinal fluid using indium 111 DTPA. Apropos of 300 cases].

A study of the C.S.F. circulation by intrathecal injection of radioactive tracers has become a common technic of neurological exploration. Among the molecules used at present, Indium111 DTPA has numerous advantages for this type of study. It is a chelating agent, the renal clearance of which is rapid and which has no toxicity at the dose injected. Indium111 is a product of the cyclotron and the physical period (2.8 days) is compatible with the duration of the examination. Finally the dose of radioactivity delivered by this isotope is less than that Iodine131, Technetium99m and Ytterbium169. In normal subjects after injection by the lumbar route, the average biological period measured by external counting lies between 20 and 28 hours. A study of the circulation of the C.S.F. is particularly useful in patients suspected of hydrocephalus. It permits finer diagnosis and shows the indications and type of by pass operation that may be neccssary. A marked increase in the biological period of Indium111-DTPA seems to be a good indication for such an operation. Our experience of 300 patients has shown the interest of the use of Indium111-DTPA which now seems to be the best radio-isotope for the study of the subarachnoid space.

Arnold-Chiari Malformation↗
PubMedDate not supplied

[Gammacisternography and fronto-basal head injuries (author's transl)].

The authors give the results of 65 radioisotopic cisternographies for suspected rhinorrheas in frontal basal head injuries. Indium 111-DTPA lombar injection allows the investigation at least for 48 hours. After localisating the CSF fistulae, the gammacisternography permits us to study associated CSF circulation anomalies. Results and discussion give the correlation between positive tests and surgical findings. The best successful conditions of exploration are enough activity and a fluent clinical leakage of CSF. Nasal coton pledgets improve the success of the exploration.

Cerebrospinal Fluid Rhinorrhea↗