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N Vigneron

Publications and source records attributed to N Vigneron.

18 recordsLinked to original sources
PubMed2005

A peptide derived from melanocytic protein gp100 and presented by HLA-B35 is recognized by autologous cytolytic T lymphocytes on melanoma cells.

A panel of autologous cytolytic T lymphocyte (CTL) clones have been isolated from blood lymphocytes of a melanoma patient after in vitro stimulation with autologous tumor cells. We previously reported the molecular definition of three distinct antigens recognized by some of these CTL clones. We describe here, the identification of a fourth antigenic peptide expressed by this melanoma line and recognized by a CTL clone restricted by HLA-B*3503. The antigenic peptide, which is nine-amino acid long, has the sequence LPHSSSHWL and is derived from melanocyte differentiation antigen gp100. As HLA-B35 is one of the most frequent HLA-B alleles, being present in 20% of the Caucasian individuals, this peptide may be a good target for peptide-based immunotherapy of melanoma.

Amino Acid Sequence↗
PubMed1998

[Treatment of polycythemia. I--Using radiophosphorus with or without treatment in 483 patients over 65 years of age].

AIMS: To compare by a prospective study in high risk polycythemia vera (PV) patients 33P alone and 32P followed by low-dose hydroxyurea (HU) maintenance therapy. Toxicity, efficiency, and leukemogenic potential were studied. PATIENTS: 483 patients with a documented PV, aged more than 65 years at diagnosis, were included between 1980 and 1996 in a prospective study comparing 32P alone and 32P followed by low-dose HU maintenance therapy. Blood cell counts were performed every two months and a clinical evaluation by a specialist was obtained every four or six months. RESULTS: Treatments were well tolerated, but chronic leg ulcers were observed in the maintenance therapy arm. The risk of leukemia was about 15% at the 15th year in the group of patients treated by 32P alone, but reached 30% in the group receiving maintenance therapy. In both arms, there was no significant correlation between occurrence of leukemia and the total dose of 32P. There was a correlation between the leukemic risk and disease severity, estimated on the frequency of relapse. Cancer occurrence was slightly higher than expected in the maintenance arm. HU treatment did not protect against progression to myelofibrosis, probably due to the lack of maintenance of an efficient myeloid or megakaryocytic suppression. Median life-span was slightly shorter in the group receiving HU maintenance. In all cases, life-span was only one year lower than that observed in the reference population. CONCLUSION: For all these reasons, we suggest the us of 32P alone in elderly patients; complementary chemotherapy should only be prescribed in the cases with short-term relapse, and late resistance to 32P.

Aged↗
PubMed1996

Somatostatin receptor imaging in small cell lung cancer.

To determine its usefulness, we evaluated 111In-DTPA-Octreotide (octreotide scintigraphy) in the initial staging of 19 patients with histologically proven small cell lung cancer (SCLC) and compared the results to those of conventional imaging. Images performed during initial staging demonstrated 21 known pulmonary lesions and two known supraclavicular nodes. We detected a previously unknown mediastinal lesion. The number of metastases was underestimated, with no liver (5), brain (1) or skin metastases detected. Bone lesions were identified in 4 out of 5 patients. There were fewer lesions detected with octreotide scintigraphy than with bone scintigraphy (except for one case). We therefore conclude that octreotide scintigraphy is a highly effective method for detecting SCLC primary tumour and supraclavicular nodes; the procedure is of limited value for distant metastasis. Further studies are needed to establish its ability for detecting residual intrathoracic disease, and confirm the value of octreotide scintigraphy in differentiating residual disease from other benign lesions.

Adult↗
PubMed1990

"Luxury perfusion" with 99mTc-HMPAO and 123I-IMP SPECT imaging during the subacute phase of stroke.

To compare the merits of 123I-isopropyl-iodoamphetamine (123I-IMP) and 99mTc-HMPAO in showing abnormal brain uptake distribution during cerebral ischemia, we studied ten patients during the subacute phase of their stroke, a period where metabolism and blood flow are frequently uncoupled. SPECT imaging was performed using both radiopharmaceuticals in the 10 patients from 48 h to 4 weeks after onset of symptoms. Two patients out of the 10 had similar defects with 123I-IMP and 99mTc-HMPAO SPECT, the location of the defects corresponding to the area of infarction observed on CT. Six patients had normal 99mTc-HMPAO SPECT and abnormal 123I-IMP SPECT with defects in the area of infarction shown by CT. The remaining 2 patients had hyperactive abnormalities on 99mTc-HMPAO in areas corresponding to defects on the 123I-IMP images. Two of the patients with SPECT mismatches were studied again more than 1 month after onset. On reexamination, 99mTc-HMPAO SPECT which was previously normal or hyperactive became hypoactive with a focal area of decreased activity corresponding to the defect on 123I-IMP. Crossed cerebellar diaschisis was found in 7 patients with 99mTc-HMPAO and was absent for both 123I-IMP and 99mTc-HMPAO in 3. We suggest that SPECT with 99mTc-HMPAO could show transient hyperemia not demonstrated by 123I-IMP whereas in some cases cerebral infarction would be more difficult to demonstrate with 99mTc-HMPAO than with 123I-IMP. SPECT with both tracers is recommended to follow the evolution of strokes in terms of regional cerebral blood flow and tissue metabolism.

Adult↗
PubMed1987

Amines for brain tomoscintigraphy.

Amines like N-isopropyl-p-123I-iodoamphetamine (IMP) and hydroxy 123I-iodobenzyl propyl diamine (HIPDM) associated with brain tomoscintigraphy have proved their worth for detecting ischaemic abnormalities. Even though the chemistry of their metabolism and their biodistribution are not fully understood, their application in the study of parenchymal impairment in stroke and reversible ischaemia yields additional information compared to the other methods of imaging like CT or MRI. The concept of a steady state in brain with a wash in/wash out model has been considered especially with IMP, to explain the evolution of the activity pattern with time when comparing early and delayed images. (This review leads to foresee the prognosis of of ischaemic diseases when redistribution is taken into account.)

Amphetamines↗
PubMed1987

Temporal evolution of brain distribution of IMP and HIPDM. Concise communication.

Early and late brain distribution of iodine-labelled N,N,N'-trimethyl-N'-(2-hydroxy-3-methyl-5-iodobenzyl)-1,3-propanediamine (HIPDM) and iodine labelled N-isopropyl-p-iodoamphetamine (IMP) were compared in rat and one human patient with a recent stroke in the right middle cerebral artery area. In rat, an important 'redistribution' of cerebral activity was observed in various areas of the brain, mainly white matter, whereas no such observation was made with HIPDM. In the patient, the right area was hypoactive during the early SPECT with IMP and HIPDM, and redistribution was observed in the late SPECT only with IMP. We suggest that while HIPDM appears to reflect regional cerebral perfusion, IMP distribution is dependent upon metabolic brain activity.

Aged↗
PubMed1986

Value of the 99mTc-methylene diphosphonate bone scan in renal osteodystrophy.

The value of radionuclide bone scanning in the diagnosis of renal osteodystrophy is still debated. In order to re-examine this issue, 25 uremic patients treated by intermittent hemodialysis underwent 99m-Technetium Methylene Diphosphonate (99mTc-MDP) bone scan. They were subdivided into three groups according to quantitative bone histology. Group 1 (N = 8) had pure dialysis osteomalacia, group 2 (N = 7) mixed lesions, and group 3 (N = 10) pure osteitis fibrosa. The scintigraphic studies were interpreted by means of a five point semi-quantitative scale. Using this quantification, all but one group 1 patients had decreased bone tracer uptake, and all patients of group 3 had an increased uptake (chi square test of Yates, P less than 0.001). Among patients of group 2, bone uptake was decreased in the three patients with clearly reduced mineralization front and moderate osteitis fibrosa, but it was increased in all patients with severe osteitis fibrosa and subnormal mineralization front. A quantitative analysis of regional tracer uptake into bone was performed in two patients: one of group 2 and one of group 3. The results obtained clearly corroborated the semi-quantitative findings. Thus, in hemodialysis patients with symptomatic bone disease, the 99mTc-MDP bone scan provides useful information for the differential diagnosis between dialysis-related osteomalacia and secondary hyperparathyroidism. In patients with mixed lesions, the importance of bone tracer uptake appears to depend on the extent of the mineralization front and on the intensity of osteitis fibrosa.

Adult↗
PubMed1985

Diagnostic value of bone marrow imaging with 111indium-transferrin and 99m technetium-colloids in myelofibrosis.

111Indium--transferrin (111In) and 99mTechnetium-colloids (99mTc) bone marrow imaging of 55 myelofibrosis (MF) cases has been compared with clinical, histological, and iron-kinetics data. The best correlations are seen between the splenic uptake of 111In with the spleen/sacrum ratio of 59Fe at the first hour (r = 0.69, P less than 0.001) and also with the splenic erythropoiesis histologically assessed in ten splenectomized patients (r = 0.75, P less than 0.01). Moreover, sacrum uptake of 111In, when compared with sacrum uptake of 59Fe (r = 0.51, P less than 0.001) and with hematopoietic cellularity of the bone marrow (r = 0.57, P less than 0.001) reflects faithfully the hematopoietic cell content of the marrow. Thus, 111In bone marrow imaging provides a noninvasive and useful tool for the diagnosis of myeloid metaplasia in MF. Ferrokinetic studies still appreciate with better insight the amount of ineffective erythropoiesis or hemolysis and remains therefore of great value when splenectomy is discussed.

Adult↗
PubMed1984

[Gougerot-Sjögren syndrome. Functional study of the salivary glands by scintigraphy].

One-hundred and twenty patients with sicca syndrome, connective tissue disease or chronic graft-versus-host disease were investigated in the Saint-Louis Hospital Department of Nuclear Medicine. Technetium scanning of the salivary glands was performed in all patients. The results of the scintigraphic study were closely correlated with clinical and histological data in patients with Sjögren's syndrome. This method, which accurately quantifies the salivary function without danger nor discomfort to the patients, has a number of advantages: (a) it is sensitive enough to detect minimal salivary gland dysfunction; (b) it differentiates between parotid gland and submandibular gland involvement and demonstrates asymmetry in pathological processes; (c) it helps in following up patients with Sjögren's disease and in assessing the results of immunosuppressive or anti-inflammatory treatment.

Adolescent↗
PubMed1984

An analysis of prognostic factors in preleukemia: interest of bone marrow scintigraphy.

Simultaneous bone marrow scintigraphy with 99m Technetium colloids and 111 Indium transferrin was performed on 34 cases of preleukemic anemias and was shown to be of good prognostic value. Groups of different outcome were defined: for a normal and parallel uptake of the two markers, 90% of the patients died of acute leukemia; for a low Indium and high Technetium uptake, only 1 patient out of 15 died of leukemia (P less than 0.001). Standard clinical and hematological data were of no predictive value. Iron kinetic data and CFU/GM colony growth were correlated to the scintigraphic results. Taken together, these three kinetic parameters have a good sensitivity and specificity for the prognosis of preleukemic states.

Aged↗
PubMed1983

[Lymphoscintigraphy and internal breast curettage in breast cancer. Comparison of results. 32 cases].

Thirty-two women with breast cancer considered in active phase underwent, successively: internal mammary lymphoscintigraphy with 99m rhenium sulfide, chemotherapy and Pathey-type mastectomy with dissection of the axillary and internal mammary lymph nodes. Lymphoscintigraphy was successful in 97% of the cases, without complications. Its specificity was 0.88 (range: 0.76--0.99) and the sensitivity 0.6 (range: 0.19--0.92). Internal mammary lymph node dissection was technically successful in 87.5% of the cases; one patient developed chondritis. Thus, lymphoscintigraphy is usually successful, without morbidity and specific. However, it cannot pretend to provide a complete answer, as does internal mammary producing invaded lymph nodes.

Adult↗
PubMed1983

[Anemia in renal insufficiency. I--Mechanisms of anemia in patients treated with periodic hemodialysis].

Fifty-two patients with anaemia due to chronic renal insufficiency treated by haemodialysis were divided into three severity groups. Except for bi-nephrectomized patients, none of the usual criteria such as age, sex, cause of the renal disease and duration of dialysis correlated with clinical severity. Kinetic studies showed that the severity of anaemia was unrelated to the degree of haemolysis, haemoglobin function or haemodilution. Stem cells were increased in all cases, irrespective of clinical severity. However, the degree of anaemia closely correlated with the degree of erythropoietic deficiency, as measured by radio-iron kinetics. A qualitative defect (slow release of labelled cells from the bone marrow) was associated with severe quantitative erythroid defect. These data indicate that kinetic studies of erythropoiesis constitute objective methods for measuring clinical severity. They favour the theory which makes a hypothetical inhibitor of differentiation and/or proliferation of erythropoietic precursors the main cause of anaemia.

Anemia↗
PubMed1982

Gastric emptying and intragastric distribution of lipids in man. A new scintigraphic method of study.

We measured gastric emptying of fat and water from a solid-liquid meal in healthy volunteers using a tubeless scintigraphic method. Selenium-75 glycerol triether, incorporated in butter, was the lipid-phase marker, and technetium-99m, ingested with 250 ml water, the non-lipid phase marker. In seven of these subjects we also measured the gastric emptying of solids and liquids with technetium-99m bound to cooked egg whites as the solid-phase marker and indium-111 ingested with 250 ml water as the marker of the solid and aqueous phases. Emptying and intragastric repartition of each marker were measured by detection of radioactivity changes over the abdominal area using a gamma-camera. The stability and the specificity of the labeling was checked for each marker. Mean gastric emptying rate (expressed as percentage ingested marker emptied per hr) of lipids (17.4 +/- 2.4) was much lower than that of the rest of the meal (34.2 +/- 1.8) and slightly, but significantly, lower than that of solids (22.8 +/- 1.8). An intragastric layering of fat above nonlipids was observed only after the first postprandial hour and remained moderate. Thus, lipids are emptied more slowly than any other component of an ordinary meal, and this is not due only to layering of fat above water.

Adult↗
PubMed1978

Fetal weight estimation by ultrasonic measurement of abdominal circumference.

The purpose of this study was to compare ultrasonic measurements of fetal abdominal circumference to ultrasonic measurements of fetal biparietal diameter, as a means of estimating fetal body weight. Of 58 fetuses who had abdominal circumferences measured, 48 (82%) of the predicted weights were within 15% of the actual birth weights. Forty-four of the same 58 fetuses had satisfactory biparietal diameter measurements, but only 21 (48%) of the predicted weights were within 15% of the actual birthweights. Ultrasonic measurement of abdominal circumference appears to be a more reliable index of fetal body weight than other currently available techniques.

Abdomen↗