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1.
Eur J Nucl Med Mol Imaging ; 48(3): 874-882, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32820369

RESUMO

INTRODUCTION: This pilot study evaluated the imaging performance of pretargeted immunological positron emission tomography (immuno-PET) using an anti-carcinoembryonic antigen (CEA) recombinant bispecific monoclonal antibody (BsMAb), TF2 and the [68Ga]Ga-labelled HSG peptide, IMP288, in patients with metastatic colorectal carcinoma (CRC). PATIENTS AND METHODS: Patients requiring diagnostic workup of CRC metastases or in case of elevated CEA for surveillance were prospectively studied. They had to present with elevated CEA serum titre or positive CEA tumour staining by immunohistochemistry of a previous biopsy or surgical specimen. All patients underwent endoscopic ultrasound (EUS), chest-abdominal-pelvic computed tomography (CT), abdominal magnetic resonance imaging (MRI) and positron emission tomography using [18F]fluorodeoxyglucose (FDG-PET). For immuno-PET, patients received intravenously 120 nmol of TF2 followed 30 h later by 150 MBq of [68Ga]Ga-labelled IMP288, both I.V. The gold standard was histology and imaging after 6-month follow-up. RESULTS: Eleven patients were included. No adverse effects were reported after BsMAb and peptide injections. In a per-patient analysis, immuno-PET was positive in 9/11 patients. On a per-lesion analysis, 12 of 14 lesions were positive with immuno-PET. Median SUVmax, MTV and TLG were 7.65 [3.98-13.94, SD 3.37], 8.63 cm3 [1.98-46.64; SD 14.83] and 37.90 cm3 [8.07-127.5; SD 43.47] respectively for immuno-PET lesions. Based on a per-lesion analysis, the sensitivity, specificity, positive-predictive value and negative-predictive value were, respectively, 82%, 25%, 82% and 25% for the combination of EUS/CT/MRI; 76%, 67%, 87% and 33% for FDG-PET; and 88%, 100%, 100% and 67% for immuno-PET. Immuno-PET had an impact on management in 2 patients. CONCLUSION: This pilot study showed that pretargeted immuno-PET using anti-CEA/anti-IMP288 BsMAb and a [68Ga]Ga-labelled hapten was safe and feasible, with promising diagnostic performance. TRIAL REGISTRATION: ClinicalTrials.gov NCT02587247 Registered 27 October 2015.


Assuntos
Neoplasias Colorretais , Radioisótopos de Gálio , Anticorpos Monoclonais , Antígeno Carcinoembrionário , Neoplasias Colorretais/diagnóstico por imagem , Fluordesoxiglucose F18 , Compostos Heterocíclicos com 1 Anel , Humanos , Oligopeptídeos , Projetos Piloto , Tomografia por Emissão de Pósitrons
2.
Int J Legal Med ; 134(3): 1003-1006, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32125503

RESUMO

We present the case of a 17-year-old man, who died after 2,4-dinitrophenol (DNP) and clenbuterol consumption, which he likely took for physical enhancement. Forensic post-mortem examination revealed a yellowish skin colour and nonspecific signs of asphyxia. Analytical confirmation of the intoxication was obtained in blood and urine, with high levels of DNP and clenbuterol. Both of these substances are used by bodybuilders as DNP enhance lipolysis and clenbuterol has anabolic properties, but their toxicity is underestimated. DNP uncouples oxidative phosphorylation, leading to thermogenesis and even relatively small doses can cause fatal hyperthermia. Clenbuterol is a ß2 agonist that causes electrolyte disturbances (hypokalemia and hyperglycemia mostly) and death have been described through coronary vasospasm. Given the circumstances in which the body was found and toxicological results, we believe the cause of death to be fatal hyperthermia from DNP intake. These substances are illegal in many countries, but easily bought online. Through this availability, the last decades have seen an increase of fatal intoxications. Websites selling them are regularly closed by French public authorities and Interpol, but unfortunately it seems insufficient.


Assuntos
2,4-Dinitrofenol/intoxicação , Clembuterol/intoxicação , Overdose de Drogas , Toxicologia Forense , Hipertermia/induzido quimicamente , Adolescente , Evolução Fatal , Humanos , Masculino
3.
Q J Nucl Med Mol Imaging ; 59(2): 161-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25752501

RESUMO

Beta-emitting radionuclides are not able to kill isolated tumor cells disseminated in the body, even if a high density of radiolabeled molecules can be targeted at the surface of these cells because the vast majority of emitted electrons deliver their energy outside the targeted cells. Alpha-particle emitting radionuclides may overcome this limitation. It is thus of primary importance to test and validate the radionuclide of choice, the most appropriate carrier molecule and the most promising clinical indication. Four α-particle emitting radionuclides have been or are clinically tested in phase I studies namely 213Bi, 225Ac, 212Pb and 211At. Clinical safety has been documented and encouraging efficacy has been shown for some of them (213Bi and 211At). 211At has been the most studied and could be the most promising radionuclide but 225Ac and 212Pb are also of potential great interest. Any carrier molecule that has been labeled with ß-emitting radionuclides could be labeled with alpha particle-emitting radionuclide using, for some of them, the same chelating agents. However, the physical half-life of the radionuclide should match the biological half-life of the radioconjugate or its catabolites. Finally everybody agrees, based on the quite short range of alpha particles, on the fact that the clinical indications for alpha-immunotherapy should be limited to the situation of disseminated minimal residual diseases made of small clusters of malignant cells or isolated tumor cells.


Assuntos
Partículas alfa/uso terapêutico , Portadores de Fármacos/síntese química , Imunoterapia/métodos , Neoplasias/radioterapia , Radioisótopos/uso terapêutico , Medicina Baseada em Evidências , Humanos , Marcação por Isótopo/métodos
4.
Nucl Med Biol ; 41 Suppl: e66-74, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24485990

RESUMO

INTRODUCTION: This paper proposes liposomes as a potential new tool for radioimmunotherapy in solid tumours with a two step targeting system. Tumour pretargeting is obtained by using a monoclonal bispecific antibody (BsmAb, anti CEA x anti-DTPA-In) and pegylated liposomes containing lipid-hapten (DSPE-DTPA-In or DSPE-PEG-DTPA-In). To optimise at the same time in vivo behaviour and specific targeting, the study focuses on the liposome formulation in order to determine more precisely the role of pegylation on both the blood half-life and the specific recognition with the BsmAb. METHODS: Different liposome formulations containing two PEG length (1000 and 2000) in varying amount (1.5-6 mol%) were prepared with DTPA directly coupled to DSPE or at the end of the PEG chain (DSPE-DTPA or DSPE-PEG-DTPA). Liposomes were immobilized on an L1 chip to measure by SPR (Surface Plasmon Resonance) the effect of pegylation on the BsmAb recognition of the DTPA-In hapten. Pharmacokinetic studies were performed in mice. Tumour targeting was studied in nude mice xenografted with human colorectal adenocarcinoma cells that express CEA, and doubly radiolabelled liposomes (with (111)In and (125)I) injected 24h after the BsmAb. RESULTS: The best in vitro apparent dissociation constant was obtained with liposomes bearing DTPA at the end of the PEG chain (KD=6.3 nM), which showed significant specific tumour uptake after BsmAb injection (8.6 ± 2.4% ID/g at 24h versus 4.5 ± 0.5%ID/g for passive targeting, α=0.01). All tumour/organ ratios were superior to 1 at 24h for this formulation, except for the spleen. CONCLUSION: The feasibility of specific tumour targeting in mice with a BsmAb and radiolabelled liposomes was demonstrated and the interest of SPR to predict their targeting performance in vivo was highlighted. This original and new approach provides promising prospects for the radioimmunotherapy of solid tumours.


Assuntos
Anticorpos Biespecíficos/imunologia , Haptenos/imunologia , Lipossomos/química , Lipossomos/uso terapêutico , Polietilenoglicóis/química , Radioimunoterapia/métodos , Adenocarcinoma/patologia , Adenocarcinoma/radioterapia , Animais , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Colorretais/radioterapia , Feminino , Humanos , Lipossomos/imunologia , Lipossomos/farmacocinética , Camundongos
5.
J Phys Chem A ; 118(9): 1568-75, 2014 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-24422714

RESUMO

The effect of α-radiolysis on the behavior of heptavalent technetium has been investigated in 13 and 18 M H2SO4. Irradiation experiments were performed using α-particles ((4)He(2+), E = 68 MeV) generated by the ARRONAX cyclotron. UV-visible and X-ray absorption fine structure spectroscopic studies indicate that Tc(VII) is reduced to Tc(V) under α-irradiation. Extended X-ray absorption fine structure (EXAFS) spectroscopy measurements are consistent with the presence of mononuclear technetium sulfate complexes. Experimental results and density functional calculations show the formation of [TcO(HSO4)3(H2O)(OH)](-) and/or [TcO(HSO4)3(H2O)2] and [Tc(HSO4)3(SO4)(H2O)] and/or [Tc(HSO4)3(SO4)(OH)](-) for 13 and 18 M H2SO4, respectively.


Assuntos
Partículas alfa , Teoria Quântica , Sulfatos/química , Ácidos Sulfúricos/química , Tecnécio/química , Estrutura Molecular , Espectroscopia por Absorção de Raios X
6.
Nucl Med Biol ; 41 Suppl: e36-43, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24361353

RESUMO

INTRODUCTION: Among the number of generator systems providing radionuclides with decay parameters promising for imaging and treatment applications, there is the (44)Ti (T1/2=60 years)/(44)Sc (T1/2=3.97 h) generator. This generator provides a longer-lived daughter for extended PET/CT measurements compared to the chemically similar system (68)Ge/(68)Ga. Scandium also exists as (47)Sc, a potential therapeutic radionuclide. It is possible to produce (44)Sc in a cyclotron using, for example, the (44)Ca (d, n) (44)Sc nuclear reaction. In that case, the isomeric state (44 m)Sc (T1/2=58.6h) is co-produced and may be used as an in vivo(44 m)Sc/(44)Sc generator. The aim of this study is to evaluate the feasibility of this in vivo(44 m)Sc/(44)Sc generator and to demonstrate that the daughter radionuclide stays inside the chelator after decay of the parent radionuclide. Indeed, the physico-chemical process occurring after the primary radioactive decay (EC, IT, Auger electron …) has prevented in many cases the use of in-vivo generator, because of the post-effect as described in the literature. METHODS: The DOTA macrocyclic ligand forms stable complexes with many cations and has been shown to be the most suitable chelating moiety for scandium. Initially, the radiolabeling of DOTA and a DOTA-peptide (DOTATATE) with Sc was performed and optimized as a function of time, pH, metal-to-ligand ratio and temperature. Next, the physico-chemical processes that could occur after the decay (post-effect) were studied. (44 m)Sc(III)-labeled DOTA-peptide was quantitatively adsorbed on a solid phase matrix through a hydrophobic interaction. Elutions were then performed at regular time intervals using a DTPA solution at various concentrations. Finally, the radiolabelled complex stability was studied in serum. RESULTS: Radiolabeling yields ranged from 90% to 99% for metal-to-ligand ratio ranging from 1:10 to 1:500 for DOTA or DOTATATE respectively. The optimum physico-chemical parameters were pH=4-6, t=20 min, T=70°C. Then, the (44 m)Sc-DOTATATE complex, radiolabeled at 98%, was adsorbed through a hydrophobic interaction to a solid phase. Unlabeled scandium was completely eluted from the column whereas the Sc-DOTATATE complex was 100% retained. The release of (44)Sc from the complex due to decay was less than 1% over 2 periods of (44 m)Sc, independent of the DTPA concentration used for elution. (44 m)Sc/(44)Sc-DOTATATE was stable in serum over 72 h. CONCLUSIONS: The results indicate that the decay of (44 m)Sc to (44)Sc does not affect the integrity of the radiolabeled compound. Thus the (44 m)Sc/(44)Sc generator is chemically valid and stable in serum. It could be used for PET imaging as an in-vivo generator increasing the life time of the scandium and allowing the use of antibody as labelled compound. Further in-vivo biological evaluations should complete this work.


Assuntos
Compostos Heterocíclicos com 1 Anel/química , Marcação por Isótopo/métodos , Octreotida/química , Tomografia por Emissão de Pósitrons/métodos , Radioisótopos , Escândio/química , Ciclotrons , Estabilidade de Medicamentos , Estudos de Viabilidade , Marcação por Isótopo/instrumentação
7.
Surg Radiol Anat ; 32(7): 689-92, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20490494

RESUMO

The pterygopalatomaxillary suture is considered as having an important role in the posteroanterior growing of the maxilla. To determine whether this suture is a growing suture in the fetus, we performed a histological study of this suture in a fetus aged of 16 weeks of amenorrhea. Serial sections (5 microm) of the pterygopalatomaxillary suture area have been performed. Fibrous sutures are separating four pieces of ossification (maxilla, palatine bone, lateral and medial plates of the pterygoid process). A fibroblastic growing site has been observed on the dorsal aspect of the pterygopalatomaxillary suture, in contact to the anterior border of the lateral plate of the pterygoid process. The posteroanterior growing of maxilla is dependent on a growing suture located on the anterior border of the pterygoid process. The pterygoid process (via its lateral plate) makes the junction between the maxilla and both the cranial base and the condylar mandibular site of growth.


Assuntos
Suturas Cranianas/embriologia , Feto/anatomia & histologia , Maxila/embriologia , Fossa Pterigopalatina/anatomia & histologia , Osso Esfenoide/embriologia , Humanos , Palato Duro/embriologia
8.
Kidney Int ; 77(4): 350-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19940839

RESUMO

The prognosis of autosomal recessive polycystic kidney disease is known to correlate with genotype. The presence of two truncating mutations in the PKHD1 gene encoding the fibrocystin protein is associated with neonatal death while patients who survive have at least one missense mutation. To determine relationships between genotype and renal and hepatic abnormalities we correlated the severity of renal and hepatic histological lesions to the type of PKHD1 mutations in 54 fetuses (medical pregnancy termination) and 20 neonates who died shortly after birth. Within this cohort, 55.5% of the mutations truncated fibrocystin. The severity of cortical collecting duct dilatations, cortical tubule and glomerular lesions, and renal cortical and hepatic portal fibrosis increased with gestational age. Severe genotypes, defined by two truncating mutations, were more frequent in patients of less than 30 weeks gestation compared to older fetuses and neonates. When adjusted to gestational age, the extension of collecting duct dilatation into the cortex and cortical tubule lesions, but not portal fibrosis, was more prevalent in patients with severe than in those with a non-severe genotype. Our results show the presence of two truncating mutations of the PKHD1 gene is associated with the most severe renal forms of prenatally detected autosomal recessive polycystic kidney disease. Their absence, however, does not guarantee survival to the neonatal period.


Assuntos
Doenças Fetais/genética , Doenças Fetais/patologia , Mutação , Rim Policístico Autossômico Recessivo/genética , Rim Policístico Autossômico Recessivo/patologia , Receptores de Superfície Celular/genética , Genótipo , Humanos , Recém-Nascido , Fenótipo
10.
Clin Cancer Res ; 13(18 Pt 2): 5592s-5597s, 2007 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-17875794

RESUMO

PURPOSE: Colorectal carcinoma is frequently accompanied by small lymph nodes metastases that often escape pathologic examination. We evaluated whether ex vivo radioimmunodetection with the Affinity Enhancement System (AES) could improve detection of mesocolonic metastases. EXPERIMENTAL DESIGN: A bivalent 111In-labeled hapten was injected (16 patients) 4 days after a bispecific antibody (anticarcinoembryonic antigen, antihapten). Surgery was done 1 to 3 days later, and radioactive uptake in the mesocolon was recorded. Extensive pathologic examination of the mesocolon (reference method) was done after fat dissolution. This method visualizes all lymph nodes but is not in routine use. RESULTS: The reference method disclosed 705 nodes. There was no significant difference between the number of node metastases detected by AES or by the reference method (16 versus 17). Better detection would have been obtained by AES than by routine pathology (P<0.01). In addition 12 extranodal metastases were found in this study of which eight were detected by AES. The prognostic importance of such extranodal metastases has been underlined in the literature. Routine pathology combined with AES would have disclosed all node metastases and 86% of total metastases versus 35% by routine pathology alone. CONCLUSIONS: Ex vivo radioimmunodetection could improve nodal and extranodal metastases detection in patients with colorectal cancer. Its value for improving pathologic analysis, together with the effect of these small metastases on prognosis, should be further evaluated. The benefit of adjuvant chemotherapy for patients upstaged with radioimmunodection should also be assessed because adjuvant chemotherapy improves the 5-year survival of stage III patients.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Neoplasias do Colo/diagnóstico por imagem , Radioisótopos de Índio , Radioimunodetecção , Adenocarcinoma/secundário , Adenocarcinoma/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Biespecíficos , Antígeno Carcinoembrionário/imunologia , Neoplasias do Colo/patologia , Neoplasias do Colo/cirurgia , Haptenos , Humanos , Linfonodos , Metástase Linfática/diagnóstico por imagem , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Oligopeptídeos/química , Prognóstico
11.
Int J Pharm ; 344(1-2): 110-7, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17592745

RESUMO

The aim of this study was to design liposomes as radioactivity carriers for pretargeted radioimmunotherapy with favorable pharmacokinetic parameters. To monitor the liposomes integrity in vivo, their surface was radiolabeled with indium-111 bound to DTPA-derivatized phosphatidylethanolamine (DSPE-DTPA) and the aqueous phase was labeled by using an original active loading technique of radioiodinated Bolton-Hunter reagent (BH) that reacts with pre-encapsulated arginine to form a positively charged conjugate ((125)I-BH-arginine). Different formulations of doubly radiolabeled liposomes were tested in vitro and in vivo to evaluate radiolabeling stability, integrity of the vesicles and their pharmacokinetics. Radiolabeling yields were high (surface >75%, encapsulation >60%) and stable (>85% after 24 h in serum 37 degrees C). In vivo, the pharmacokinetic behavior of doubly radiolabeled liposomes was strongly dependant on the formulation. Blood clearance of PEGylated liposomes (DSPC/Chol/DSPE-DTPA/DSPE-PEG5%) was 0.15 mL/h compared to a conventional formulation (DSPC/Chol/DSPE-DTPA: clearance 1.44 mL/h). Non-encapsulated BH-arginine conjugate was quickly eliminated in urine (clearance 6.04 mL/h). Blood kinetics of the two radionuclides were similar and radiochromatographic profiles of mice serum confirmed the integrity of circulating liposomes. The significant reduction of activity uptake in organs after liposome catabolism (liver and spleen), achieved by the rapid renal elimination of (125)I-BH-arginine, should bring significant improvements for targeted radionuclide therapy with sterically-stabilized liposomes.


Assuntos
Radioisótopos de Índio , Radioisótopos do Iodo , Lipossomos/química , Animais , Arginina/química , Sistemas de Liberação de Medicamentos , Estabilidade de Medicamentos , Feminino , Indicadores e Reagentes , Marcação por Isótopo , Lipossomos/farmacocinética , Camundongos , Camundongos Endogâmicos BALB C , Radioimunoterapia , Succinimidas/química , Distribuição Tecidual
12.
Q J Nucl Med Mol Imaging ; 51(1): 51-60, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17372573

RESUMO

AIM: Radioimmunotherapy is limited in some cases by the low radioactive doses delivered to tumor cells by antibodies or pretargeted haptens. In order to increase this dose, lipidic nanocapsules (LNC) with a hydrophobic core are proposed as radionuclide vectors that could be targeted to cancer cells by a bispecific anti-tumor x anti-hapten antibody after incorporation of different haptens in the nanocapsule membrane. METHODS: To bind different radionuclides to the nanocapsules, several bifunctional chelating agents (BCA) were used to form stable complexes with the radionuclides. Some of them are hydrophilic for LNC shell while others are lipophilic to radiolabel the core. Poly(ethylene glycols) (PEG) were used to increase the residence time in blood. Since PEG can modify haptens recognition by the bispecific antibody and radiolabeling efficiency, haptens, BCA or Bolton-Hunter reagent (BH) were attached to the PEG extremity to optimize accessibility. Specific constructs (DSPE-PEG-haptens, DSPE-PEG-BCA, and DSPE-PEG-BH) were synthesized to develop these new radiolabeled vector formulations. Large amounts of PEG have been introduced by a postinsertion method without important change in nanocapsule size and properties. The nanocapsule core was radiolabeled with a lipophilic [(99m)Tc]SSS complex. RESULTS: Serum stability studies showed that this (99m)Tc-labeling method was efficient for at least 20 h. Concerning the nanocapsule surface, several methods have been performed for (111)In-labeling by using DSPE-PEG-DTPA and for (125)I-labeling with DSPE-PEG-BH. CONCLUSIONS: The nanocapsules labeling feasibility with a variety of radionuclides and their stability were demonstrated in this paper.


Assuntos
Portadores de Fármacos/química , Marcação por Isótopo/métodos , Lipídeos/química , Lipossomos/química , Nanocápsulas/química , Radioimunoterapia/métodos , Radioisótopos/química , Difusão , Sistemas de Liberação de Medicamentos/métodos , Estabilidade de Medicamentos , Estudos de Viabilidade , Nanocápsulas/ultraestrutura , Tamanho da Partícula , Radioisótopos/administração & dosagem
13.
Phys Med Biol ; 52(4): 1013-25, 2007 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-17264367

RESUMO

Murine models are useful for targeted radiotherapy pre-clinical experiments. These models can help to assess the potential interest of new radiopharmaceuticals. In this study, we developed a voxel-based mouse for dosimetric estimates. A female nude mouse (30 g) was frozen and cut into slices. High-resolution digital photographs were taken directly on the frozen block after each section. Images were segmented manually. Monoenergetic photon or electron sources were simulated using the MCNP4c2 Monte Carlo code for each source organ, in order to give tables of S-factors (in Gy Bq-1 s-1) for all target organs. Results obtained from monoenergetic particles were then used to generate S-factors for several radionuclides of potential interest in targeted radiotherapy. Thirteen source and 25 target regions were considered in this study. For each source region, 16 photon and 16 electron energies were simulated. Absorbed fractions, specific absorbed fractions and S-factors were calculated for 16 radionuclides of interest for targeted radiotherapy. The results obtained generally agree well with data published previously. For electron energies ranging from 0.1 to 2.5 MeV, the self-absorbed fraction varies from 0.98 to 0.376 for the liver, and from 0.89 to 0.04 for the thyroid. Electrons cannot be considered as 'non-penetrating' radiation for energies above 0.5 MeV for mouse organs. This observation can be generalized to radionuclides: for example, the beta self-absorbed fraction for the thyroid was 0.616 for I-131; absorbed fractions for Y-90 for left kidney-to-left kidney and for left kidney-to-spleen were 0.486 and 0.058, respectively. Our voxel-based mouse allowed us to generate a dosimetric database for use in preclinical targeted radiotherapy experiments.


Assuntos
Rim/efeitos da radiação , Método de Monte Carlo , Radioisótopos/farmacocinética , Radiometria/métodos , Baço/efeitos da radiação , Glândula Tireoide/efeitos da radiação , Animais , Carga Corporal (Radioterapia) , Transferência Linear de Energia , Camundongos , Camundongos Nus , Eficiência Biológica Relativa , Processamento de Sinais Assistido por Computador , Contagem Corporal Total
14.
Plast Reconstr Surg ; 118(7): 1538-1542, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17102725

RESUMO

BACKGROUND: Orbitofacial clefts are caused by a congenital absence of midfacial tissues between the eye and the upper lip just medial to the corner of the mouth. As a whole, facial clefts occur with an incidence of 1.43 to 4.85 per 100,000 births. The exact incidence of these unusual orbital facial clefts is unknown. Only a few clinical cases and their treatment have been reported in the world literature, and no anatomical or histologic study has been presented. METHODS: The authors present a detailed anatomical and histologic study in a 24-week-old fetus with a right-side no. 5 orbitofacial cleft (according to Tessier's classification). RESULTS: During the anatomical dissection, it was observed that in the trigeminal Gasser ganglion on the right side there was no infraorbital branch of this nerve. Both the foramen rotundum and the infraorbital groove, where the nerve exits, were hypotrophic. CONCLUSION: After embryologic analysis of their observation, the authors propose that the orbitofacial no. 5 cleft should be considered as a tissular disruption of the face secondary to damage of the terminal branches of the maxillary nerve.


Assuntos
Anormalidades Múltiplas/diagnóstico por imagem , Anormalidades Múltiplas/patologia , Face/anormalidades , Face/diagnóstico por imagem , Feto/anormalidades , Feto/diagnóstico por imagem , Órbita/anormalidades , Órbita/diagnóstico por imagem , Face/patologia , Feto/patologia , Idade Gestacional , Humanos , Órbita/patologia , Radiografia
15.
Phys Med Biol ; 51(3): 601-16, 2006 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-16424584

RESUMO

Dosimetric studies are necessary for all patients treated with targeted radiotherapy. In order to attain the precision required, we have developed Oedipe, a dosimetric tool based on the MCNPX Monte Carlo code. The anatomy of each patient is considered in the form of a voxel-based geometry created using computed tomography (CT) images or magnetic resonance imaging (MRI). Oedipe enables dosimetry studies to be carried out at the voxel scale. Validation of the results obtained by comparison with existing methods is complex because there are multiple sources of variation: calculation methods (different Monte Carlo codes, point kernel), patient representations (model or specific) and geometry definitions (mathematical or voxel-based). In this paper, we validate Oedipe by taking each of these parameters into account independently. Monte Carlo methodology requires long calculation times, particularly in the case of voxel-based geometries, and this is one of the limits of personalized dosimetric methods. However, our results show that the use of voxel-based geometry as opposed to a mathematically defined geometry decreases the calculation time two-fold, due to an optimization of the MCNPX2.5e code. It is therefore possible to envisage the use of Oedipe for personalized dosimetry in the clinical context of targeted radiotherapy.


Assuntos
Radiometria/métodos , Radioterapia/métodos , Simulação por Computador , Estudos de Avaliação como Assunto , Humanos , Imageamento por Ressonância Magnética , Modelos Anatômicos , Modelos Estatísticos , Modelos Teóricos , Método de Monte Carlo , Imagens de Fantasmas , Fótons , Planejamento da Radioterapia Assistida por Computador , Reprodutibilidade dos Testes , Software
16.
Curr Med Chem ; 12(3): 319-38, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15723622

RESUMO

Pretargeted delivery of radionuclides is based upon bispecific immunoconjugates that bind a target tumor antigen and a small molecule carrying the active payload. This strategy is supposed to combine the advantage of antibodies to track tumor cells in vivo and of small radiolabeled molecules that clear rapidly from normal organs and minimize toxicity. Many pretargeting approaches have been proposed, but only those using the biotin/avidin recognition system and those using bispecific anti-tumor x anti-hapten antibodies have been tested in the clinic for both immunoscintigraphy and radioimmunotherapy. Their respective advantages and drawbacks, as well as hurdles in the way of an effective therapy against solid tumors, are discussed. In the light of the encouraging results obtained so far in the clinic, pretargeting remains a most promising challenge for chemistry and biotechnology.


Assuntos
Neoplasias/radioterapia , Radioimunoterapia/métodos , Animais , Anticorpos Biespecíficos/administração & dosagem , Avidina/análogos & derivados , Avidina/uso terapêutico , Biotina/análogos & derivados , Biotina/uso terapêutico , Epitopos , Haptenos/uso terapêutico , Humanos , Neoplasias/irrigação sanguínea , Peptídeos/uso terapêutico , Radioisótopos/uso terapêutico , Estreptavidina/análogos & derivados , Estreptavidina/uso terapêutico
17.
Bioconjug Chem ; 16(1): 184-93, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15656590

RESUMO

The feasibility of two-step radioimmunotherapy (RIT) of cancer by the Affinity Enhancement System (AES) has been demonstrated in experimental and clinical studies. This technique, associating a bispecific antibody and a bivalent peptide radiolabeled with iodine-131, has been developed to reduce toxicity and to improve therapeutic efficacy compared to one-step targeting methods. The use of AES with different beta-emitters such as rhenium-188, samarium-153, or lutetium-177 or alpha-emitters such as actinium-225 or bismuth-213 is now considered. Thus three new peptides, designed to allow for the coupling of a variety of bifunctional chelating agents BCA, were synthesized by associating two glycyl-succinyl-histamine (GSH) arms, which are recognized by the 679 monoclonal antibody (mAb-679), with different binding agents, such as p-nitrophenylalanine or N,N-bis(carboxymethyl)-4-N'-(9-fluorenylmethyloxycarbonyl)aminobenzylamine. Immunoreactivity and serum stability evaluation were performed for each synthesized peptide. One of the three peptides (LM218) proved to be more stable than the others, and three different BCAs were coupled to LM218 (CITC-DTPA, CITC-TTHA, and CITC-CHXA''DTPA). One of these products, LM218-BzTTHA was radiolabeled with indium-111 without loss of immunoreactivity toward the mAb-679. These new peptides will allow pretargeted RIT with a large variety of radionuclides, to adapt the choice of the radionuclide (LET, half-life, penetrating emission) to the nature and size of targeted tumors.


Assuntos
Histamina/análogos & derivados , Neoplasias/radioterapia , Peptídeos/síntese química , Fenilalanina/análogos & derivados , Radioimunoterapia , Radioisótopos/uso terapêutico , Animais , Anticorpos Biespecíficos/química , Anticorpos Monoclonais/química , Benzilaminas/química , Quelantes , Histamina/química , Estrutura Molecular , Fenilalanina/química , Fatores de Tempo
18.
J Clin Endocrinol Metab ; 90(2): 779-88, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15572422

RESUMO

High hematological toxicity has been observed with anti-carcinoembryonic antigen radioimmunotherapy (RIT) in medullary thyroid carcinoma (MTC), suggesting metastatic bone involvement (BI). This retrospective study evaluated the rate of BI in MTC patients enrolled in two phase-I/II RIT trials using anti-carcinoembryonic antigen x anti-diethylenetriamine pentaacetic acid bispecific antibodies and [(131)I]di-diethylenetriamine pentaacetic acid hapten. Thirty-five patients underwent bone scintigraphy, bone magnetic resonance imaging (MRI), and post-RIT immunoscintigraphy (IS). IS performed in MTC patients was compared with IS conducted in 12 metastatic colorectal carcinoma (CRC) patients. Quantitative analysis of bone uptake was performed in three MTC and three CRC patients. In the MTC group, bone scintigraphy detected BI in 56.6% of patients, MRI in 75.8%, and IS in 88.6%. BI was confirmed by undirected (random) bone marrow biopsy, by bone surgery, or by two positive imaging methods in 74.3% of the patients. Sensitivity per patient of bone scintigraphy, MRI, and IS were 72.7, 100, and 100%, respectively. In contrast, IS visualized BI in only 33.3% of CRC patients; bone uptake was lower in CRC than in MTC patients. Bone MRI combined with post-RIT IS disclosed a much higher BI rate in advanced MTC than previously reported in the literature.


Assuntos
Medula Óssea/patologia , Osso e Ossos/patologia , Neoplasias da Glândula Tireoide/patologia , Adulto , Idoso , Neoplasias Ósseas/patologia , Neoplasias Ósseas/secundário , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Radioimunoterapia , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/radioterapia
19.
Cell Mol Biol (Noisy-le-grand) ; 50(3): 281-9, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15209349

RESUMO

Because of a possible relationship between microenvironmental disturbances and meiotic abnormalities and of a straight relationship between lower-quality semen in patient carrying a varicocele and first meiotic non-disjunction, bilateral bipolar testicular biopsies are realized according the thermic differential gradient described in varicocele. Systematic meiotic studies of multiple testicular biopsies from 65 azoospermic men with bilateral varicocele were done in a multi-centric study on microsurgical correction of bilateral varicocele with microthermic intra-operative evaluation using minimally invasive thermal microsensors (Betatherm 10K3MCD2). In the present study abnormal temperature raising, histomorphometric abnormalities (spermatocyte arrest) and meiotic abnormalities (class IIC) are strongly correlated. In the ten patients submitted to another testicular biopsy procedure six months after surgery for TESE, normal thermal differential is registered and no meiotic abnormalities recurrences are found.


Assuntos
Meiose , Oligospermia/patologia , Varicocele/cirurgia , Biópsia , Temperatura Corporal , Núcleo Celular/ultraestrutura , Aberrações Cromossômicas , Humanos , Infertilidade Masculina/etiologia , Masculino , Microeletrodos/estatística & dados numéricos , Microcirurgia , Oligospermia/etiologia , Estágio Paquíteno , Testículo/irrigação sanguínea , Testículo/patologia , Termômetros/estatística & dados numéricos , Varicocele/complicações
20.
Ultrasound Obstet Gynecol ; 23(3): 262-6, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15027015

RESUMO

OBJECTIVE: To investigate the use of high-intensity focused ultrasound (HIFUS) to reduce uterine artery blood flow in ewes in the postpartum period. METHODS: HIFUS was applied to the uterine arteries of seven ewes in the postpartum period. Arterial flow velocities were measured before and after the procedure at the site of HIFUS application (target), as well as 3 cm upstream and 3 cm downstream from the target. The uterine arteries were then removed for macroscopic and histological examination. RESULTS: Maximum flow velocities in the target area increased after the procedure by 350% and those upstream from the target decreased by 65%. Macroscopically, the vessel diameter was shown to have reduced at the site of HIFUS application. Microscopically, both the endothelium and media showed thermal lesions. Tissues surrounding the arteries were macroscopically and microscopically normal. CONCLUSION: Exposure of uterine arteries to HIFUS reduces the vessel diameter and thus induces a dramatic increase in the maximum flow velocities within the target area. HIFUS may have a role in the treatment of postpartum hemorrhage.


Assuntos
Hemorragia Pós-Parto/terapia , Terapia por Ultrassom/métodos , Animais , Artérias/patologia , Artérias/fisiopatologia , Velocidade do Fluxo Sanguíneo , Modelos Animais de Doenças , Feminino , Humanos , Período Pós-Parto/fisiologia , Fluxo Sanguíneo Regional , Ovinos , Terapia por Ultrassom/instrumentação , Útero/irrigação sanguínea
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