Biomedical subjects

G Paganelli

Publications and source records attributed to G Paganelli.

At least 91 records · Page 5Linked to original sources

PubMed1997

Pretargeting strategies for radio-immunoguided tumour localisation and therapy.

The selective recognition of tumour cells by monoclonal antibodies, labelled with radioactive isotopes, for use in diagnosis and treatment, forms the basis of immunoscintigraphy, radio-immunoguided surgery and radio-immunotherapy. Research into the application of these systems has encountered multiple difficulties, most notably a low tumour to non-tumour ratio of radioactivity. The development of pretargeting systems, separating the individual steps of tumour cell targeting and the introduction of the radioactive label, have led to significant increments in tumour to non-tumour ratios and an improvement in diagnostic accuracy. Before pretargeting strategies are applied clinically, a thorough understanding of these systems is required and forms the backbone of this report. Clinical examples of early trials have already confirmed many of the theoretical advantages of pretargeting systems and new protocols are already being investigated.

Antibodies, Monoclonal↗

PubMed1997

Biodistribution in tumour-bearing mice of two 90Y-labelled biotins using three-step tumour targeting.

Tumour pretargeting techniques based on a three-step approach with the avidin/biotin system and associated with the high-energy beta-emitter yttrium-90 (90Y) have been applied with encouraging results in cancer therapy. While in-vivo stable binding of 90Y through a chelating agent like DOTA is essential for directly labelled monoclonal antibodies in the labelling of a fast clearing molecule like biotin, this may not be so important, since the time for catabolic processes to occur is drastically reduced. In this study, the biodistribution of 90Y bound to biotin through DTPA or DOTA was evaluated. Tumour-bearing mice received biotinylated antibody on day 1, avidin on day 2 and 90Y-labelled biotin on day 3. The biodistribution was determined 4 and 24 h after the injection of radiolabelled biotin. The majority of the injected dose was recovered in the urine 4 h after injection of both radiolabelled compounds. Higher bone uptake of 90Y was observed in animals administered 90Y-DTPA-biotin. In general, all organs including tumour showed higher accumulation of activity following the injection of 90Y-DAPA-biotin. Despite the lower levels of accumulation in the tumour after injection of 90Y-DOTA-biotin, the tumour-to-liver and tumour-to-bone ratios for the DOTA ligand were higher compared to DTPA. The higher tumour uptake observed after injection of 90Y-DTPA-biotin may be attributed to the presence of two biotin molecules in its dimeric structure. Our results indicate that the ideal 90Y-labelled biotin derivative for therapy studies should be formed from a DOTA core with two non-cleavable spacers, each ending with a biotin molecule.

Adenocarcinoma↗

PubMed1997

Acquisition protocol for breast cancer imaging with technetium-99m-labeled synthetic peptide and technetium-99m-MDP.

UNLABELLED: Technetium-99m-MDP and, recently, a 99mTc-labeled synthetic decapentapeptide have been shown to localize in breast lesions. Our goal was to develop an acquisition protocol to improve image quality, to improve detection of axillary lymph nodes with disease and to compare the utility of the new radiotracer to 99mTc-MDP. METHODS: Ninety-three patients with documented breast carcinoma were studied. Thirty-eight patients were studied in the supine position with anterior and lateral views: eight patients were injected intravenously with 600-740 MBq 99mTc-EPPT and 30 patients with the same activity of 99mTc-MDP. A second group of 55 patients was studied using the same total activity: 20 patients were injected with 99mTc-EPPT and 35 patients with 99mTc-MDP. To improve results, patients were positioned standing up with their arm raised. The breast with a marker over the nipple touched the collimator in the oblique-lateral position. Early planar images (2-5 min postinjection) were acquired with this positioning for the healthy and the tumor breast, collecting 1500 K counts in a 256 x 256 matrix. Imaging of the axillary regions was performed while the patients were positioned supine and a frontal image was obtained at 10-15 min postinjection for 1800 K counts. RESULTS: This diagnostic study produced good quality images, with the breast lesions and axilla visualized. The positions had limitations due to the overlapping of other organs and to the proximity with the chest wall. CONCLUSION: Using this protocol, all primary lesions and 50% of the axillary lymph nodes with 99mTc-MDP, and 35% with 99mTc-EPPT, were detected as documented by histology. Our protocol may represent an improvement in the diagnosis and staging of breast cancer.

Axilla↗

PubMed1997

Tumor pretargeting: role of avidin/streptavidin on monoclonal antibody internalization.

UNLABELLED: Radioimmunodetection of tumor can be improved by introducing a two-step system in which radiolabeled streptavidin is administrated after the injection of a biotinylated monoclonal antibody (MAb) (two-step) or radiolabeled biotin is injected after biotinylated MAb and avidin (three-step). The anti-carcinoembryonic antigen (CEA) MAb FO23C5 has been recently exploited in a three-step protocol based on the avidin-biotin system. The anti-folate receptor (FR) MAb MOv18 has proven suitable for radioimmunodetection of ovarian cancer using directly radiolabeled MAb or in a two-step method. In this study, we analyzed the suitability of MOv18 in a three-step protocol in ovarian carcinoma patients and the internalization events after formation of the MOv18-avidin complex. METHODS: Selected patients with documented metastatic lesions were enrolled in a three-step radioimaging analysis with biotinylated MOv18 and FO23C5, avidin and (111)In-labeled biotin. Two-step internalization experiments were conducted in vitro with MOv18 and MOv19 MAbs on the FR-overexpressing IGROV1 cell line and with the anti-CEA MAb FO23C5 on the LS174T cell line. Cells were incubated sequentially with biotinylated MAb and 125I-labeled streptavidin or with 125I-biotinylated MAb and cold streptavidin. RESULTS: In the in vivo study, SPECT revealed the majority of metastatic lesions in patients injected with biotinylated MOv18; however, the tumor-to-background ratio was relatively low. In the in vitro study, a consistent internalization was induced by antigen-biotinylated MAb-streptavidin complex formation at the cell surface in both antigenic systems analyzed. However, the extent of internalization was lower in the CEA model. CONCLUSION: The internalization ability of avidin suggests its potential clinical application for delivering toxic agents in a two-step approach (biotinylated MAb + avidin conjugate). The suitability of a given MAb for three-step clinical applications (biotinylated MAb + avidin + biotin) should be previously investigated by using appropriate in vitro experiments.

Antibodies, Monoclonal↗

PubMed1996

In vivo imaging of chromogranin A-positive endocrine tumours by three-step monoclonal antibody targeting.

The detection of chromogranins (Cg) by immunohistochemistry and serology represents a new in vitro diagnostic tool for endocrine tumours. We have recently reported on the feasibility of targeting chromogranin A (CgA) for in vivo detection of pituitary adenomas by immunoscintigraphy (ISG). The scintigraphic procedure, based on an anti-CgA monoclonal antibody and on the avidin-biotin three-step method (Cg-3S-ISG), was evaluated on a group of 29 consecutive patients with known or suspected endocrine tumours other than pituitary adenomas, i.e. medullary thyroid carcinoma, carcinoid, insulinoma and parathormone- or ACTH-producing tumours. Primary tumours (10) and recurrences (16) were visualised in 26 patients, whereas conventional imaging techniques (planar radiography, computerised tomography, magnetic resonance imaging and ultrasonography) failed to detect the tumour sites in ten of the same (Cg-3S-ISG-positive) patients. Therefore, these preliminary results indicate that Cg-3S-ISG, the first immunological method able to detect endocrine tumours in vivo, has a higher diagnostic accuracy than conventional imaging techniques (93.1% compared with 65.5%).

Antibodies, Monoclonal↗

PubMed1996

Evaluation of four radiopharmaceuticals for imaging inflammation in a rabbit model of arthritis.

We compared the utility of four radiopharmaceuticals; 111In-chloride, 67Ga-citrate, 111In labeled leukocytes (WBCs) and 99mTc-MDP for assessing the inflammatory response in antigen induced arthritis in a rabbit model. A total of 20 rabbits, divided into four equal groups, were included in this study. Each group was studied twice with a single radiotracer; a baseline study and a follow-up study after induction of the arthritis. Knee to knee, knee to whole body, and knee to liver (except for the group studied with 99mTc-MDP) ratios were generated. Knee to knee ratios showed no significant change from baseline to arthritis studies in any of the four groups. Significantly increased knee to total body ratios were seen in all of the groups, except for the group studied with 99mTc-MDP. The greatest increase was seen in the group studied with 111In-chloride. Significantly increased knee to liver ratios were observed in all three groups for which these ratios were generated and again the greatest increase was observed in the group studied with 111In-chloride. In summary, based on the higher uptake observed in this group, of the four radiotracers evaluated, 111In-chloride is probably the most useful for monitoring the inflammatory response in antigen induced arthritis. The symmetry of the response suggests that it may also be useful in monitoring the response to therapy.

Animals↗

PubMed1996

Radioimmunoguided surgery and colorectal cancer.

Radioimmunoguided surgery is a technique that aims to delineate the extent of epithelial neoplasms (primary/recurrent) and their spread (local, regional, and distant) which are not adequately visualized by conventional imaging techniques. The target lesion binds radiolabelled, tumour-associated monoclonal antibodies which are administered in the days before surgery and which bind to the target lesion. The radiotracer is detected intraoperatively using a hand-held gamma detecting probe. This identifies the extent of the tumour, involvement of lymph nodes or other organs and may allow a more complete surgical clearance of the tumour. This article provides a basic understanding of the RIGS (radioimmunoguided surgery) technique, the monoclonal antibodies which are used and outlines the advantages and limitations of this technique.

Antibodies, Monoclonal↗

PubMed1996

Pretargeted immunoscintigraphy in patients with medullary thyroid carcinoma.

To evaluate the use of pretargeted immunoscintigraphy (ISG) in the diagnosis and follow-up of patients with medullary thyroid carcinoma (MTC), we studied 25 patients with histologically proven disease; ISG was repeated after surgery in two patients. The antibody, either an anticarcinoembryonic antigen (CEA) or an antichromogranin A (CgA) biotinylated monoclonal antibody (MAb) or a cocktail of the two biotinylated MAbs was first injected. After 24 h, avidin was administrated i.v., followed by 111In-labelled biotin 24 h later. Fifty-two lesions were visualised. Six primary tumours, diagnosed by increased calcitonin levels, were all correctly diagnosed; 47 recurrences, also suspected by blood tumour markers, were detected and confirmed by cytology or histology. In one case, single photon emission tomography allowed the detection of small lymph nodes with a diameter of 4-7 mm. These lesions, not judged neoplastic by ultrasound, were confirmed to be neoplastic by fine needle aspiration. Pretargeted ISG correctly localises primary tumours and recurrences in MTC patients, when the only marker of relapse is serum elevation of calcitonin. With this three-step pretargeting method, cocktails of potentially useful MAbs can be used, avoiding false-negative studies that may occur when CEA or CgA are not expressed.

Adolescent↗

PubMed1996

Three-step immunoscintigraphy with anti-chromogranin A monoclonal antibody in tumours of the pituitary region.

In the present paper we evaluated the ability of pretargeted immunoscintigraphy (ISG) with antichromogranin A (CgA) monoclonal antibody (Mc-ab A11) in visualizing pituitary masses. The results obtained in 23 patients are described along with those of [111In]pentetreotide scintigraphy (Octreoscan) in 18 cases. Positive ISG was obtained in 9/11 (82%) non-functioning, 1/4 growth hormone-, 1/2 prolactin-, 1/2 thyrotropin-, 1/1 follicle-stimulating hormone-, 0/1 adrenocortico-trophin-secreting pituitary adenomas. In one patient with a positive ISG scan of a non-functioning pituitary adenoma, an associated neurinoma of the acoustic nerve was not imaged. The same occurred in one patient with a pituitary deposit from a mammary carcinoma and in another one with a cyst of the Rathke's pouch. Chromogranin A immunohistochemistry, carried out in 10 tumours, was positive in eight pituitary adenomas and negative in two non-adenomatous lesions. A concordant ISG occurred in all cases except for two pituitary adenomas: one cystic and necrotized and one post-operative remnant very small in size. In 18 patients with pituitary adenoma both ISG and Octreoscan were positive in 61% of cases but with a different distribution among tumours. At variance with ISG, Octreoscan visualized only 5/10 (50%) non-functioning pituitary adenomas and all (4/4) somatotropinomas. In conclusion, ISG is able to image pituitary tumours and particularly non-functioning pituitary adenomas. In this respect, it may be helpful in discriminating non-neuroendocrine masses of the pituitary region from non-functioning pituitary adenomas.

Adolescent↗

PubMed1996

Detection of prosthetic vascular graft infection using avidin/indium-111-biotin scintigraphy.

UNLABELLED: Prosthetic vascular graft infection, though rare, carries high morbidity and mortality rates; therefore, timely diagnosis is important. Patients, however, often present with vague symptoms, and radiological investigations are frequently inconclusive. These factors may lead to prolonged periods of observation and hospitalization, with the resultant increase in costs and complication rates, before reaching a final diagnosis. This prospective study evaluates the use of nonspecific avidin/111In-biotin imaging in diagnosing prosthetic vascular graft infection. METHODS: Twenty-five patients with a total of 29 grafts were investigated. Eighteen patients (19 grafts) had low probability of disease, whereas the remaining 7 patients (10 grafts) warranted surgical exploration based on clinical, laboratory or radiological evidence. Avidin was first injected intravenously and then followed 24 hr later by administration of 111In-biotin. Whole-body images were obtained 10 min and 2 hr postinjection of 111In-labeled biotin. SPECT imaging was performed 1 hr postinjection. Increased uptake along part or the whole length of the graft was considered evidence of graft infection. RESULTS: Avidin/111In-biotin scintigraphy correctly identified all infected grafts, as confirmed by culturing surgical specimens. In contrast, infection was correctly excluded in all but one of the grafts, and long-term follow-up was used to assess the presence of infection in patients who did not undergo surgical intervention. CONCLUSION: Avidin/111In-biotin scintigraphy is a simple and accurate imaging method for the routine diagnosis of vascular graft infection, and it may have a role in identifying the disease process in its initial stages, thus improving prognosis.

Aged↗

PubMed1996

Quantitative comparison of direct antibody labeling and tumor pretargeting in uveal melanoma.

UNLABELLED: SPECT radioimmunoscintigraphy with 99mTc-labeled anti-melanoma monoclonal antibodies (MAbs) 225.28S is being used to detect uveal melanoma. Recently, pretargeting methods have been described to reduce background activity and perform imaging in a shorter time interval. METHODS: We compared the three-step pretargeting method with conventional radioimmunoscintigraphy in 15 patients with a clinical and laboratory diagnosis of uveal lesion. High-resolution SPECT radioimmunoscintigraphy was performed in all patients with directly labeled MAbs and, 1 wk later, with the three-step pretargeting technique. Eleven patients underwent eye enucleation and specimens of uveal melanoma were available for histology, whereas four patients underwent conservative therapy. The percent injected dose (%ID) delivered to the tumor and the tumor-to-background ratio were calculated. RESULTS: In all three-step radioimmunoscintigraphy studies, there was a reduction of nonspecific nasopharyngeal background. The three-step radioimmunoscintigraphy tumor-to-nontumor ratio was 3.1 +/- 1.3 versus 1.5 +/- 0.5 of conventional radioimmunoscintigraphy, while the percent injected dose on the tumor was similar for the two methods (4.4 +/- 3.0 versus 3.8 +/- 2.8) x 10(-3). CONCLUSION: Improved SPECT imaging with the three-step radioimmunoscintigraphy results from reduced background and from higher counting statistics due to reduction of time interval between radiotracer administration and imaging, whereas the absolute amount of tracer delivered to the tumor by the two methods is comparable.

Antibodies, Monoclonal↗

PubMed1996

Imaging osteomyelitis with streptavidin and indium-111-labeled biotin.

UNLABELLED: Animal studies of infection imaging by a two-step protocol have shown that important improvements in target to nontarget ratios are possible. In this protocol, unlabeled streptavidin is administered and allowed sufficient time to accumulate in the lesion, probably by nonspecific processes, and to clear elsewhere. Thereafter, 111Inbiotin is administered. A fraction of the labeled biotin may be retained in the lesion because of biotin's high affinity for streptavidin while most of the activity is cleared through the kidneys. METHODS: Radioscintigraphy with unlabeled streptavidin followed with 111Inlabeled biotin was performed in 15 patients with chronic osteomyelitis. As controls, each patients received either 111In-labeled biotin without the preadministration of streptavidin or 111In-labeled nonspecific IgG. RESULTS: Regions of focal uptake were identified in all patients receiving streptavidin followed by radiolabeled biotin as early as 10 min postadministration of radioactivity, and retention of label was evident through 24 hr. Coincident regions of abnormal accumulation were apparent with 111In-IgG, but only in delayed images. Moreover, with 111In-biotin alone, without the preadministration of streptavidin, focal accumulations were detected in areas similar to that identified with the two-step protocol. Although, these observations were only in the earliest images. CONCLUSION: The results of this preliminary clinical investigation suggest that a two-step protocol with unlabeled streptavidin and radiolabeled biotin may be an alternative for the detection of infection.

Adult↗

PubMed1995

Avidin and 111In-labelled biotin scan: a new radioisotopic method for localising vascular graft infection.

OBJECTIVES: To evaluate a new imaging technique, for diagnosis of prosthetic vascular graft infection. Avidin is a protein which accumulates nonspecifically at sites of inflammation or infection. Due to its extremely low dissociation constant with biotin sites of infection can be imaged, using avidin as a pre-target, followed by injection of 111In-labelled biotin. This technique is much simpler than the common scintigraphic methods which employ labelling of blood components and its target-to-background ratio is greater than the methods employing radiolabelled proteins. DESIGN: Prospective clinical study. SETTING: A single department of vascular surgery and one of nuclear medicine of a Northern Italian hospital. MATERIALS: Between May 1993 and May 1994, 31 grafts in 26 patients were studied; the series included 23 men and three women with a mean age of 65.5 years (range 54-76 years). The prosthetic graft (Dacron -16, ePTFE -15) were: aortoaortic 5, aortobifemoral 15, aortoiliac 1, and femoropopliteal 10. Sixteen patients were suspected of having a vascular graft infection (Group A), the other 10 patients served as controls (Group B). 20 mg of Avidin were injected iv, followed 24 h later by i.v. injection of 500 micrograms of Biotin labelled with 74 MBq of 111In. CHIEF OUTCOME MEASURES: Whole-body imaging was performed at 10 min and 2 h post-injection, along with SPECT imaging when indicated. Scan results were correlated with the traditional imaging modalities and the clinical outcome of the patients. MAIN RESULTS: In Group A: two patients (three grafts) were excluded from the study, there were six true-positives, one false-positive and 11 true-negatives. Results in Group B: 10 true-negatives. The overall sensitivity was 100%, the specificity 95%, the accuracy 96%, the positive predictive value 86% and the negative predictive value 100%. CONCLUSIONS: These data suggest that Avidin/111In-labelled Biotin scintigraphy is a useful non invasive diagnostic method for early diagnosis of suspected prosthetic vascular graft infection.

Aged↗

PubMed1994

Pre-targeted immunodetection in glioma patients: tumour localization and single-photon emission tomography imaging of [99mTc]PnAO-biotin.

The imaging of cerebral gliomas with radiolabelled monoclonal antibodies (MoAbs) has been previously reported. However, previous studies have been hampered by the drawback of a low tumour to non-tumour ratio. In order to overcome this problem we have developed a three-step pre-targeting method using the avidin-biotin system. The rationale of this technique consists in vivo labelling of biotinylated MoAbs targeted onto tumour deposits, when most of the unbound antibodies have been cleared from the bloodstream as avidin-bound complexes. The anti-tenascin MoAb BC2, specific for the majority of gliomas, was biotinylated and 1 mg was administered i.v. in 20 patients with histologically documented cerebral lesions. After 24-36 h, 5 mg avidin was injected i.v. followed 24 h later by a third i.v. injection of 0.2 mg PnAO-biotin labelled with 15-20 mCi technetium-99m. No evidence of toxicity was observed. Whole-body biodistribution was measured at 20 min, 3 h and 5 h post-injection. [99mTc]PnAO-biotin had a fast blood clearance and was primarily excreted through the biliary system. A dedicated single-photon emission tomography system was used to acquire brain tomographic images 1-2 h after the administration of [99mTc]PnAO-biotin. Tumours were detected in 15/18 glioma patients with a tumour to non-tumour ratio of up 14:1. This three-step method, based on the sequential administration of anti-tenascin MoAb BC2, avidin and [99mTc]PnAO-biotin, can support computed tomography or magnetic resonance imaging for the diagnosis and follow-up of patients with glioma. Further studies are required to evaluate the potential of this technique for therapeutic application.

Astrocytoma↗

PubMed1994

Avidin-biotin system in radioimmunoguided surgery for colorectal cancer. Advantages and limits.

PURPOSE: Radiolabeled monoclonal antibodies (MAbs) have been reported to allow tumor intraoperative detection by means of a gamma-detecting probe. The technology is called the Radioimmunoguided Surgery (RIGS) system. The main inconveniences of the method are 1) the long interval needed for clearance of unattached MAbs from the patient's body, between the injection of the MAb and surgery, and 2) the low sensitivity of current MAbs used in detecting small tumors. We describe a new method to overcome these inconveniences using biotinylated MAbs and avidin in order to obtain a rapid blood clearance of the radiolabeled MAbs both anticarcinoembryonic antigen and antitumor-associated glycoprotein-72 MAbs. METHODS: Twenty patients with primary and recurrent colorectal cancer have been enrolled in the study; 125I-biotinylated MAbs FO23C5 (anticarcinoembryonic antigen) and B72.3 (antitumor-associated glycoprotein-72) followed by cold avidin were injected in 13 patients and 7 patients, respectively. RESULTS: A decrease of 94 +/- 3 percent of circulating radioactivity was achieved in 3 to 5 days. Patients underwent surgery approximately seven days after MAb injections rather than after four weeks. Tumors were localized in 14/20 (70 percent) patients (true positive), 2 (10 percent) were false negative, and 4 (20 percent) were true negative. The overall sensitivity level in early-stage primary cancers was 37 percent when related to the presence of disease and 75 percent when related to antigenic expression. The sensitivity for more advanced cancer and for recurrences was 100 percent. Moreover, the in vivo tumor targeting of biotinylated MAb was demonstrated in frozen tumor section by direct streptoavidin-peroxidase staining. CONCLUSIONS: The avidin-biotin system may enhance applicability and effectiveness of radioimmunoguided surgery (RIGS).

Antibodies, Monoclonal↗

PubMed1994

Combined use of 111In-labeled pentetreotide and three-step immunoscintigraphy with antichromogranin A monoclonal antibody in the diagnosis of pituitary adenomas.

For various pituitary adenomas, it has been demonstrated that somatostatin receptor can be present. Pilot studies have shown that radio-indium labeled pentetreotide allows very good scintigraphic localization of somatostatin receptor-bearing cell masses. Recently, the presence of CgA in pituitary adenomas has also been demonstrated. MAb A11, raised against CgA, has been successfully used with a three-step ISG for the diagnosis of neuroendocrine tumors. Therefore the combined use of three-step ISG with MAb A11 and radiolabeled somatostatin can be useful in the diagnosis of pituitary adenomas. Twelve patients, 5 secreting (group A) and 7 nonsecreting (group B) pituitary adenomas, were enrolled in the study. All patients underwent three-step ISG, and, 2 wk later, scintigraphy with 111In-labeled pentetreotide (Octreoscan). Three-step ISG consisted of i.v. injection of 1 mg of biotinylated MAb A11 (first step), followed by 10 mg of avidin (second step) and [99mTc]PnAO-biotin (third step). Tomographic imaging were acquired for three-step ISG and Octreoscan at 2 and 4 h after radiotracer injection, respectively. The results are the following: 2 patients of group A (secreting tumors) had a positive three-step ISG, whereas all the patients but one of the same group had a positive pentetreotide study; all the patients of group B (nonsecreting tumors) had a positive three-step ISG and 4 had a positive pentetreotide scintigraphy. These data suggest the utility of the combined use of these techniques for a better diagnosis of pituitary adenomas.

Adenoma↗

PubMed1994

Impact of enteral nutrition on intestinal bacterial translocation and mortality in burned mice.

The aim of these experiments was to study the effect of early enteral nutrition with either standard or enriched (arginine, n-3 fatty acids, RNA) enteral formulas on translocation of bacteria from the gut and acute mortality rate following thermal injury. In the first experiment 60 Balb c mice were gavaged with 10(10)Escherichia coli and received a 20% burn injury. In 40 mice enteral nutrition (20 standard, 20 enriched) was started immediately after injury and stopped 36 h later. In the control group (n = 20) aliquotes of Ringer's solution was administered intragastrically. Mortality rate was observed for 10 days post-injury. In the second experiment 60 Balb c mice were gavaged with 10(10)E. coli labelled with biotin(111) Indium and then burned. In 40 mice enteral nutrition (20 standard, 20 enriched) was started immediately after burn. The control group (n = 20) received aliquotes of Ringer's solution. 4 h after injury all animals were sacrificed and liver, lungs, kidneys, spleen and systemic blood were harvested, and radionuclide counts were measured. No animal died after day 3 post-burn. The mortality rate was significantly lower at day 1 in the groups infused with both enteral solutions (15%) compared to controls (30%; p = 0.05). At day 3 the animals fed with the enriched diets showed a lower mortality (5%) versus the standard and control groups (10%). Bacterial translocation to the liver and lungs was significantly higher in Ringer's group than in both enterally fed groups. Early post-burn enteral nutrition reduces both translocation and acute mortality. Supplementation of the diets with specific nutrients appears to exert additional advantages on outcome.

Journal Article↗

PubMed1994

Relation between myocardial 18F-FDG uptake in the fasting state and coronary angiography in patients with coronary artery disease.

The relationship between severity of coronary artery stenosis (CAS) and myocardial 18F-2-fluoro-2-deoxy-D-glucose (18F-FDG) uptake in the fasting state, assessed with positron emission tomography (PET), was examined in a series of 48 patients with CAS undergoing both studies for diagnostic purposes. The data analysis was based on the subdivision of the left ventricular myocardium into four segments defined in relation to ventricular vascularization: the anterior and septal segments, perfused by the left anterior descending artery; the lateral segment, perfused by the left circumflex; and the inferior segment, perfused by the right coronary artery. The 192 segments were grouped according to degree of CAS: I 0-50%, II 51-75%; III 76-90%; IV 91-99%; V and VI occluded coronary artery with good or poor collaterals, respectively. An 18F-FDG index was determined as the tissue/blood pool radioactivity ratio in each segment. The statistical analysis was performed by one-way ANOVA, multiple comparison tests and the chi-squared test. The proportion of segments with 18F-FDG uptake was also analysed for a linear trend across the ordered levels of CAS. The 18F-FDG index in groups I to V was significantly higher than in controls, but it was not different among the groups with CAS, except for group V versus I. However, the proportion of segments with enhanced 18F-FDG uptake was correlated to the degree of CAS. In cases of complete occlusion of a major afferent coronary artery, the proportion of segments with 18F-FDG uptake varied in relation to the presence of collaterals.(ABSTRACT TRUNCATED AT 250 WORDS)

Collateral Circulation↗