RESUMEN
STUDY QUESTION: Is increasing the intensity of high-intensity focused ultrasound (HIFU) by 30% in the treatment of rectal endometriosis a safe procedure? SUMMARY ANSWER: This study demonstrates the safety of a 30% increase in the intensity of HIFU in the treatment of rectal endometriosis, with no Clavien-Dindo Grade III complications overall, and namely no rectovaginal fistulae. WHAT IS KNOWN ALREADY: A feasibility study including 20 patients with rectal endometriosis demonstrated, with no severe complications, a significant improvement in digestive disorders, dysmenorrhoea, dyspareunia, and health status, although the volume of the endometriosis nodule did not appear to be reduced. STUDY DESIGN, SIZE, DURATION: A prospective multicentre cohort study was conducted between 2020 and 2022 with 60 patients with symptomatic rectal endometriosis. Following the failure of medical treatment, HIFU treatment was offered as an alternative to surgery. PARTICIPANTS/MATERIALS, SETTING, METHODS: As the main objective of this study was to examine safety, all adverse events observed during the 6 months of follow-up were analysed and graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) and Clavien-Dindo classifications. Secondary objectives included evaluating the evolution of symptoms using validated questionnaires: gynaecological and digestive pain symptoms with a visual analogue scale, health status with the Medical Outcomes Study 36-item Short Form (SF-36) questionnaire, average post-operative daily pain level, and analgesic medication required in the 10 days following treatment. MRI was also performed at Day 1 to detect early complications. Finally, we performed a blinded MRI review of the evolution of the nodule at 6 months post-treatment. MAIN RESULTS AND THE ROLE OF CHANCE: The procedure was performed under spinal anaesthesia for 30% of the patients. The median duration of treatment was 32 min. Fifty-five patients left the hospital on Day 1. MRI scans performed on Day 1 did not highlight any early-onset post-operative complication. Using the Clavien-Dindo classification, we listed 56.7% Grade I events, 3.4% Grade II events, and no events Grade III or higher. At 1, 3, and 6 months, all gynaecologic, digestive and general symptoms, as well as health status, had significantly improved. The evolution of the nodule was also significant (P < 0.001) with a 28% decrease in volume. LIMITATIONS, REASONS FOR CAUTION: The main objective was safety and not effectiveness. The study was not randomized and there was no control group. WIDER IMPLICATIONS OF THE FINDINGS: HIFU treatment for rectal endometriosis results in an improvement of symptoms with low morbidity; as such, for selected patients, it could be a valuable alternative to surgical approaches following the failure of medical treatment. STUDY FUNDING/COMPETING INTEREST(S): The study was funded by the company EDAP TMS. Professors Dubernard and Rousset are consultants for EDAP TMS. Dubernard received travel support from EDAP-TMS. Dr F. Chavrier received industrial grants from EDAP-TMS. He has developed a device for generating focused ultrasonic waves with reduced treatment time. This device has been patented by EDAP-TMS. Dr Lafon received industrial grants from EDAP-TMS; he declares that EDAP-TMS provided funding directly to INSERM to support a young researcher chair in therapeutic ultrasound, which is unrelated to the current study. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov identifier NCT04494568.
Asunto(s)
Endometriosis , Enfermedades del Recto , Humanos , Femenino , Endometriosis/terapia , Endometriosis/cirugía , Endometriosis/diagnóstico por imagen , Adulto , Estudios Prospectivos , Enfermedades del Recto/terapia , Francia , Resultado del Tratamiento , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Ultrasonido Enfocado de Alta Intensidad de Ablación/efectos adversos , Persona de Mediana Edad , Dismenorrea/terapia , Dispareunia/etiología , Dispareunia/terapiaRESUMEN
OBJECTIVES: Deep infiltrating endometriosis (DIE) of the rectosigmoid is associated with painful symptoms. When medical treatment is ineffective, surgical resection remains the standard treatment, despite significant risk of adverse events. High-intensity focused ultrasound (HIFU) is a minimally invasive ablative procedure. Focal One® is a transrectal HIFU (TR-HIFU) device used in prostate cancer treatment. The primary objective of this study was to confirm the feasibility of treatment with TR-HIFU in patients presenting with posterior DIE with rectosigmoid involvement. We also assessed its safety and clinical efficacy in this context. METHODS: This was a non-controlled, prospective, Phase-I clinical trial in a French University Hospital which is a multidisciplinary center for management of endometriosis. Included were patients older than 25 years, without plans to conceive within 6 months, who presented with a single lesion of posterior DIE, with rectosigmoid invasion, after failure of hormonal therapy. All lesions were assessed preoperatively using transvaginal sonography and magnetic resonance imaging. Patients completed questionnaires on gynecological and intestinal symptoms (similar to a visual analog scale (VAS)), and on quality of life (Medical Outcomes Study 36-item short-form survey (SF-36) and, for the second half of patients recruited, symptom scoring system for constipation (KESS), female sexual function index (FSFI) and endometriosis health profile short-version score (EHP-5)), before, and at 1, 3 and 6 months after, TR-HIFU treatment with a Focal One real-time ultrasound-guided HIFU device. RESULTS: Twenty-three consecutive patients were included in the study between September 2015 and October 2019. All 23 lesions were visualized, giving a detection rate of 100%. Twenty lesions were treated ('feasibility rate', 87.0%): in 13 the whole lesion was treated and in seven the lesion was treated partially. The mean duration of the TR-HIFU procedure was 55.6 min. We observed a significant improvement in VAS score at 6 months, with differences relative to preoperative scores as follows, for: dysmenorrhea (-3.6, P = 0.004), dyspareunia (-2.4, P = 0.006), diarrhea (-3.0, P = 0.006), constipation (-3.0, P = 0.002), dyschezia (-3.2, P = 0.003), false urge to defecate (-3.3, P = 0.007), posterior pelvic pain (-3.8, P = 0.002) and asthenia (-3.8, P = 0.002). There was also a significant improvement in the SF-36 score, with an increase at 6 months relative to the preoperative score in both the physical component summary (+ 9.3%, P = 0.002) and mental component summary (+ 10.9%, P = 0.017). No major complications occurred during or after any procedure. CONCLUSIONS: TR-HIFU therapy for posterior DIE is feasible. If its efficacy and safety are confirmed, it could be a minimally invasive alternative to surgery for the treatment of rectosigmoid endometriosis. © 2019 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Asunto(s)
Endometriosis/diagnóstico por imagen , Enfermedades del Recto/diagnóstico por imagen , Ultrasonido Enfocado Transrectal de Alta Intensidad , Adulto , Endometriosis/patología , Femenino , Francia , Humanos , Persona de Mediana Edad , Dolor Pélvico , Valor Predictivo de las Pruebas , Estudios Prospectivos , Enfermedades del Recto/patología , Encuestas y CuestionariosRESUMEN
This study presents the first observation of elastic shear waves generated in soft solids using a dynamic electromagnetic field. The first and second experiments of this study showed that Lorentz force can induce a displacement in a soft phantom and that this displacement was detectable by an ultrasound scanner using speckle-tracking algorithms. For a 100 mT magnetic field and a 10 ms, 100 mA peak-to-peak electrical burst, the displacement reached a magnitude of 1 µm. In the third experiment, we showed that Lorentz force can induce shear waves in a phantom. A physical model using electromagnetic and elasticity equations was proposed. Computer simulations were in good agreement with experimental results. The shear waves induced by Lorentz force were used in the last experiment to estimate the elasticity of a swine liver sample.
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Modelos Teóricos , Ultrasonido/métodos , Animales , Simulación por Computador , Elasticidad , Hígado/química , Campos Magnéticos , Fantasmas de Imagen , Resistencia al Corte , Porcinos , Ultrasonido/instrumentaciónRESUMEN
We report a case of Epstein-Barr virus (EBV) primo infection with the development of successive infectious mononucleosis, hemophagocytic lymphohistiocytosis, and B-cell lymphoproliferative disorder in a patient treated with azathioprine for Crohn's disease. This case report suggests that specific EBV-related clinical and virological management should be considered when treating a patient with inflammatory bowel disease with azathioprine.
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Azatioprina/efectos adversos , Enfermedad de Crohn/complicaciones , Infecciones por Virus de Epstein-Barr/complicaciones , Inmunosupresores/efectos adversos , Adulto , Azatioprina/uso terapéutico , Enfermedad de Crohn/tratamiento farmacológico , Resultado Fatal , Humanos , Inmunosupresores/uso terapéutico , MasculinoRESUMEN
This paper presents an analysis, using process simulation, of the waste management system applied in a collection basin located in the south of Paris (France). The study was conducted in close cooperation with the "SYCTOM of Paris agglomeration", an operator in charge of managing 2.5 milliontons/yr of municipal solid waste in the Paris area. The analysis includes a description of the current situation of waste management in this collection basin, the construction and calibration of a simulator that reproduces this situation, the simulation of scenarios that account for possible future changes in waste flows and treatment options and finally a comparison of scenario results. Results illustrate the interest of a process-based approach to waste management systems. Such an approach is complementary to life cycle analyses, which usually rely on more generic descriptions of waste treatment units. The detailed analysis of a waste management system using local data on waste streams and treatment units provides technical indicators of system efficiency expressed in terms of recycling rates, energy recovery, emission fluxes and costs. Such information can help reach a consensus with respect to the actual situation of waste management and provides decision-makers with quantitative arguments that can be brought into the public debate.
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Simulación por Computador , Eliminación de Residuos/métodos , Algoritmos , Modelos Teóricos , ParisRESUMEN
Pancreatic ductal adenocarcinoma (PDAC) is supported by a complex microenvironment whose physical contribution to chemoresistance could be overcome by ultrasound (US) therapy. This study aims to investigate the ability of US-induced inertial cavitation in association with chemotherapy to alter tumor cell viability via microenvironment disruption. For this purpose, we used a 3D-coculture PDAC model partially mimicking the tumor and its microenvironment. Coculture spheroids combining DT66066 cells isolated from KPC-transgenic mice and murine embryonic fibroblasts (iMEF) were obtained by using a magnetic nanoshuttle method. Spheroids were exposed to US with incremental inertial cavitation indexes. Conditions studied included control, gemcitabine, US-cavitation and US-cavitation + gemcitabine. Spheroid viability was assessed by the reduction of resazurin and flow cytometry. The 3D-coculture spheroid model incorporated activated fibroblasts and produced type 1-collagen, thus providing a partial miniature representation of tumors with their microenvironment. Main findings were: (a) Gemcitabine (5 µM) was significantly less cytotoxic in the presence of KPC/iMEFs spheroids compared with KPC (fibroblast-free) spheroids; (b) US-induced inertial cavitation combined with Gemcitabine significantly decreased spheroid viability compared to Gemcitabine alone; (c) both cavitation and chemotherapy affected KPC cell viability but not that of fibroblasts, confirming the protective role of the latter vis-à-vis tumor cells. Gemcitabine toxicity is enhanced when cocultured spheroids of KPC and iMEF are exposed to US-cavitation. Although the model used is only a partial representation of PDAC, this experience supports the hypothesis that US-inertial cavitation can enhance drug penetration and cytotoxicity by disrupting PDAC microenvironment.
Asunto(s)
Carcinoma Ductal Pancreático , Desoxicitidina/análogos & derivados , Neoplasias Experimentales , Neoplasias Pancreáticas , Microambiente Tumoral/efectos de los fármacos , Terapia por Ultrasonido , Animales , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/terapia , Línea Celular Tumoral , Desoxicitidina/farmacología , Ratones , Ratones Transgénicos , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Neoplasias Experimentales/terapia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/terapia , Esferoides Celulares/metabolismo , Esferoides Celulares/patología , Gemcitabina , Neoplasias PancreáticasRESUMEN
BACKGROUND: The shape of the induced thermal ablation area is as important as its dimension. The aim of this study was to analyze the size reproducibility and the aspect of the interstitial ultrasonic ablation obtained by a planar transducer in porcine liver in vivo. METHODS: Five pigs were used. Two complete ultrasonic lesions were made in each animal under pedicle clamping. All the lesions underwent MR examination on day 7 and then a histological analysis. RESULTS: The tested probe has the advantage of providing a step-by-step and highly directional treatment in the target zone. The ultrasonic lesions presented as well-defined and homogenous areas of tissue coagulation. The lesion volumes ranged from 8.1 to 92.3 cm3 with an averaged lesion length of 56 mm at gross examination. Three-dimensional reconstruction of the lesions from the MR images showed cylindrical and conical shapes. Large intrahepatic vessels distorted the lesion shape, and the vicinity of the application to the liver surface increased significantly the volume of the ultrasonic necrosis. Histological examination showed complete necrosis in the area of damage. CONCLUSION: The ultrasonic ablation has a regular shape, always with sharply defined borders. However, it showed some variability in the size of the induced lesions.
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Neoplasias Hepáticas/terapia , Terapia por Ultrasonido/normas , Animales , Imagenología Tridimensional , Imagen por Resonancia Magnética , Porcinos , Transductores , Terapia por Ultrasonido/efectos adversosRESUMEN
High intensity ultrasounds are routinely used for thermal ablation of some cancers. However, for treating hepatic tumours with physical agents, RF applicators and cryoprobes are still preferred. The goal of the present study was to demonstrate the feasibility of using interstitial ultrasound probes in liver following two approaches: percutaneous and intra-tissular or endo vascular. In vivo trials on a porcine model demonstrated the minimally invasive nature of both procedures. Homogeneous and reproducible thermal lesions, up to 20 mm deep, were obtained. The work on these two original approaches deserves to be completed with more extended prospective studies. The association with an imaging method will have to be studied before proceeding to clinical trials.
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Hígado/patología , Terapia por Ultrasonido/métodos , Animales , Electrocoagulación/métodos , Endosonografía/instrumentación , Endosonografía/métodos , Estudios de Factibilidad , Hígado/diagnóstico por imagen , Modelos Animales , Porcinos , Transductores , Terapia por Ultrasonido/instrumentación , Ultrasonografía Intervencional/instrumentación , Ultrasonografía Intervencional/métodosRESUMEN
Using a set of overlapping peptides of the human p53 protein, we analysed the epitopes recognized by 18 monoclonal antibodies specific for human p53. We showed that most of these epitopes correspond to linear antigenic determinants which lie predominantly in the amino- or carboxy-terminus of the p53 protein. Using either truncated p53 or the set of human p53 peptides, we directly analysed the sera of animals immunized with human p53. These sera contained antibodies which also recognized the regions corresponding to the extremity of the p53 protein. These p53 regions were similar to those recognized by p53-specific antibodies present in sera of patients with cancer. Preferential recognition of these regions by antibodies specific for non conformational epitopes suggested that these regions are localized at the surface of the p53 protein as unfolded structures.
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Linfocitos B/inmunología , Epítopos Inmunodominantes/inmunología , Proteína p53 Supresora de Tumor/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos , Humanos , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Proteínas Recombinantes de Fusión/inmunologíaRESUMEN
In this study, we show that upon thrombopoietin (Tpo) stimulation the two adapter proteins Gab1 and Gab2 are strongly tyrosine phosphorylated and associated with Shc, SHP2, PI 3-kinase and Grb2 in mpl-expressing UT7 cells. Although Gab1 and Gab2 seem to mediate overlapping biological signals in many cells, only Gab1 is expressed and phosphorylated in response to Tpo in primary human megakaryocytic progenitors; furthermore, it associates with the same proteins. Although a low level of tyrosine phosphorylated IRS-2 protein is also detected in PI 3-kinase immunoprecipitates, Gab proteins are the essential proteins associated with PI 3-kinase after Tpo stimulation. We demonstrate that, albeit no association is detected between the Tpo receptor mpl and Gab proteins, Y112 located in the C-terminal cytoplasmic domain of mpl is required for Gab1/2 tyrosine phosphorylation. Gab proteins are not tyrosine phosphorylated after Tpo stimulation of UT-7 and Ba/F3 cells expressing a mpl mutant lacking Y112. Moreover, no activation of the PI 3-kinase/Akt pathway is observed in cells expressing this mpl mutant. Finally, we show that this mutant does not allow cell proliferation, thereby confirming that PI 3-kinase activation is required for Tpo-induced cell proliferation.
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Fosfatidilinositol 3-Quinasas/metabolismo , Fosfoproteínas/fisiología , Proteínas Serina-Treonina Quinasas , Trombopoyetina/farmacología , Proteínas Adaptadoras Transductoras de Señales , Animales , División Celular/efectos de los fármacos , División Celular/fisiología , Activación Enzimática/efectos de los fármacos , Sangre Fetal/citología , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/metabolismo , Humanos , Megacariocitos/citología , Megacariocitos/efectos de los fármacos , Megacariocitos/metabolismo , Ratones , Fosfoproteínas/metabolismo , Fosforilación , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-akt , Conejos , Proteínas Recombinantes/farmacología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Trombopoyetina/genética , Tirosina/metabolismoRESUMEN
In the human breast carcinoma cell line (MCF-7), exogenous TGF-beta 1 induces a dose-dependent inhibition of cell proliferation. In a MCF-7 cell subline [MCF-7(-)], which has an undetectable level of type II TGF-beta receptor, exogenous TGF-beta 1 does not inhibit cell proliferation but is still able to induce its own message. In both cell lines, TGF-beta 1 stimulates expression of c-jun, whereas a rapid, transient and marked increase in c-fos mRNA is only observed in the MCF-7 cells sensitive to the growth inhibitory effect of TGF-beta 1. Depletion of protein kinase C abolishes the c-fos but not the c-jun response to TGF-beta 1. Our results suggest that growth inhibition and autoinduction by TGF-beta 1 are mediated by different signalling pathways. In addition, a PKC-dependent increase in c-fos expression seems to be associated with the growth inhibitory effect of TGF-beta 1.
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Receptores de Activinas Tipo I , Genes fos , Genes jun , Factor de Crecimiento Transformador beta/biosíntesis , Factor de Crecimiento Transformador beta/farmacología , Adenocarcinoma/metabolismo , Marcadores de Afinidad , Neoplasias de la Mama/metabolismo , División Celular/efectos de los fármacos , Línea Celular , Humanos , Proteína Quinasa C/metabolismo , Proteínas Serina-Treonina Quinasas , ARN Mensajero/análisis , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/análisis , Transducción de SeñalRESUMEN
Activation of protein kinase C (PKC) inhibits cell cycle progression at the G1/S and G2/M transitions. We found that phorbol 12-myristate 13-acetate (PMA) induced upregulation of p21, not only in MCF-7 cells arrested in the G1 phase as previously shown, but also in cells delayed in the G2 phase. This increase in p21 in cells accumulated in the G1 and G2/M phases of the cell cycle after PMA treatment was inhibited by the PKC inhibitor GF109203X. This indicates that PKC activity is required for PMA-induced p21 upregulation and cell cycle arrest in the G1 and G2/M phases of the cell cycle. To further assess the role of p21 in the PKC-induced G2/M cell cycle arrest independently of its G1 arrest, we used aphidicolin-synchronised MCF-7 cells. Our results show that, in parallel with the inhibition of cdc2 activity, PMA addition enhanced the associations between p21 and either cyclin B or cdc2. Furthermore, we found that after PMA treatment p21 was able to associate with the active Tyr-15 dephosphorylated form of cdc2, but this complex was devoid of kinase activity indicating that p21 may play a role in inhibition of cdc2 induced by PMA. Taken together, these observations provide evidence that p21 is involved in integrating the PKC signaling pathway to the cell cycle machinery at the G2/M cell cycle checkpoint.
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Proteína Quinasa CDC2/metabolismo , Ciclinas/metabolismo , Fase G2/fisiología , Mitosis/fisiología , Proteína Quinasa C/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Afidicolina/farmacología , Proteína Quinasa CDC2/antagonistas & inhibidores , Ciclina B/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , ADN/metabolismo , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Citometría de Flujo , Fase G2/efectos de los fármacos , Humanos , Indoles/farmacología , Maleimidas/farmacología , Mitosis/efectos de los fármacos , Fosforilación , Pruebas de Precipitina , Proteína Quinasa C/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Acetato de Tetradecanoilforbol/antagonistas & inhibidores , Células Tumorales Cultivadas , Regulación hacia Arriba/efectos de los fármacosRESUMEN
The neurotrophic factor promoting activity of the neuroprotective compound SR57746A was evaluated in primary cultures of neonatal rat cortical astrocytes by studying the synthesis of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF). A concentration- and time-dependent increase of nerve growth factor mRNA was induced by SR57746A (10 nM-1 microM). In these astrocytes, BDNF mRNA contents were increased to a significant but smaller extent, and beta-actin mRNA showed no variation. SR57746A (1 microM) induced increases of both de novo protein translation after 6 h of incubation and NGF release into the extracellular medium after 6-24 h. These effects were preceded by a transient augmentation of junB, c-fos and c-jun mRNA contents. These increases of AP-1 family mRNA were associated with increased nuclear AP-1 binding activity. The results show that SR57746A can increase the synthesis and release of NGF in rat cortical astrocytes. Such effects may contribute to the drug's previously described neuroprotective effects.
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Astrocitos/metabolismo , Corteza Cerebral/metabolismo , Naftalenos/farmacología , Factores de Crecimiento Nervioso/biosíntesis , Fármacos Neuroprotectores/farmacología , Piridinas/farmacología , Animales , Animales Recién Nacidos , Astrocitos/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/biosíntesis , Factor Neurotrófico Derivado del Encéfalo/genética , Células Cultivadas , Corteza Cerebral/citología , Corteza Cerebral/efectos de los fármacos , Ensayo de Inmunoadsorción Enzimática , Factores de Crecimiento Nervioso/genética , Pruebas de Precipitina , Biosíntesis de Proteínas , ARN Mensajero/biosíntesis , Ratas , Ratas Sprague-Dawley , Endonucleasas Específicas del ADN y ARN con un Solo Filamento/metabolismo , Factor de Transcripción AP-1/metabolismoRESUMEN
The HLA-G monomorphic, nonclassic HLA class I gene encodes the molecule that is the only major histocompatibility complex antigen expressed on cytotrophoblasts of placenta. This restricted expression on fetal tissue that is in contact with maternal tissue suggests that HLA-G products may play a role in maternofetal tolerance. We previously have demonstrated in first-trimester human trophoblasts a new alternatively spliced form of HLA-G mRNA lacking exon 4 (HLA-G4) and weak expression of HLA-G1 copy mRNA in adult peripheral blood lymphocytes. By using exon-specific HLA-G primers, we demonstrate in this work the presence of three additional alternatively spliced forms of HLA-G mRNA in human peripheral mononuclear cells (HLA-G2, HLA-G3, and HLA-G4). In umbilical cord blood, HLA-G transcription was observed at very low level and only three alternatively spliced forms were detected (HLA-G1, HLA-G2, and HLA-G3). In contrast, we did not revealed any HLA-G transcript in CD34+ fraction of cord blood cells.
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Empalme Alternativo , Sangre Fetal/inmunología , Antígenos HLA/genética , Antígenos de Histocompatibilidad Clase I/genética , Leucocitos Mononucleares/inmunología , ARN Mensajero/genética , Antígenos CD34/biosíntesis , Antígenos CD34/genética , Secuencia de Bases , Sondas de ADN de HLA , Exones , Sangre Fetal/metabolismo , Expresión Génica , Antígenos HLA/biosíntesis , Antígenos HLA-G , Antígenos de Histocompatibilidad Clase I/biosíntesis , Humanos , Recién Nacido , Leucocitos Mononucleares/metabolismo , Masculino , Datos de Secuencia Molecular , ARN Mensajero/biosíntesisRESUMEN
To elucidate the mechanisms of the mammalian cell defense against cross-linking agents, we studied previously cellular responses to mitomycin C (MMC) treatment in two MMC-hypersensitive hamster cell mutants' V-H4 and V-C8, as well as their parental cell line V79. In the present report, we investigated whether alterations in cell cycle checkpoints and induction of apoptosis could be responsible for the MMC hypersensitivity of the V-H4 and V-C8 mutant cell lines. First, we found that parental and mutant cells exhibited similar cell cycle responses to MMC concentrations of equivalent cytotoxicity, arguing against a defective cell cycle checkpoint in hypersensitive cell lines. In contrast, we showed that mutant cells underwent greater levels of apoptosis following MMC treatment than parental cells. These findings indicate that increased induction of apoptosis contributes to the hypersensitivity of V-H4 and V-C8 cells to the growth inhibitory effect of MMC. This differential apoptotic response was observed with both equimolar and equitoxic MMC doses and was specific to the cross-linking agent MMC, suggesting that control of the apoptotic process is altered in both MMC-hypersensitive mutants. The defective genes in V-H4 and V-C8 cells would then function in the regulation of an apoptotic pathway triggered by MMC-induced damage and independent of p53-mediated transcription.
Asunto(s)
Apoptosis , Mitomicina/farmacología , Animales , Antibióticos Antineoplásicos/farmacología , Ciclo Celular/efectos de los fármacos , Células Cultivadas , Cricetinae , Cricetulus , MutaciónRESUMEN
Biliary cancer is very difficult to treat, mainly because of the advanced stage at which such tumours are detected and the low efficacy of systemic therapeutic modalities like radiotherapy. Palliative measures designed to clear the duct (either by means of surgery or an endoscopic procedure) are presently performed. A relatively noninvasive alternative could be developed to fill this gap in the therapeutic arsenal. To this end, we have designed an interstitial ultrasound (US) applicator suitable for use with a digestive endoscope. This applicator is based on a water-cooled plane transducer that operates at 10 MHz. Although, because the target zone is cylindrical in shape, it might have seemed more logical to use a cylindrical transducer. Nevertheless, a plane transducer was chosen because the pressure field from this kind of emitter decreases less quickly, which means faster and deeper heating. However, to generate coagulation necrosis all around the duct, the applicator has to be rotated around its axis; this is achieved by means of a flexible metallic shaft (2 m in length and 3. 8 mm in diameter) that joins the device's active head (which contains the transducer) to the casing with all the connectors. A holder is fixed at the endoscope channel inlet; it controls the rotation of the applicator. Trials were conducted on pigs. The duodenoscope was introduced via the oesophagus down through the duodenum as far as the hepatopancreatic ampulla. Using a guide wire, the applicator was navigated into the duct via the endoscope instrument channel. Well defined, reproducible volumes of coagulation necrosis with a diameter of 20 mm were generated in the biliary tissue and the liver. These promising results indicate that this kind of endoscopic US delivery system may represent an effective tool for the treatment of biliary tumours in humans. An Independent Ethics Committee recently approved preliminary clinical trials of this applicator.
Asunto(s)
Endoscopía del Sistema Digestivo/métodos , Terapia por Ultrasonido/instrumentación , Animales , Enfermedades de los Conductos Biliares/diagnóstico por imagen , Enfermedades de los Conductos Biliares/patología , Enfermedades de los Conductos Biliares/terapia , Conductos Biliares Intrahepáticos/diagnóstico por imagen , Conductos Biliares Intrahepáticos/patología , Conducto Colédoco/diagnóstico por imagen , Conducto Colédoco/patología , Diseño de Equipo , Necrosis , Reproducibilidad de los Resultados , Porcinos , UltrasonografíaRESUMEN
The extracorporeal high-intensity focused ultrasound (HIFU) techniques are not still transposable for tumors of the digestive tract because of their locations. This study was designed to evaluate the feasibility of interstitial applicators (3.8 mm O.D.) to comply with this therapeutic lack and to demonstrate the possibility of producing coagulation necrosis by a specially designed probe and with a short exposure time (20 s). The active surface of the applicators consists of plane water-cooled PZT transducers working at 10 or 5 MHz. They were evaluated in terms of acoustic power emitted as a function of the frequency, and applied electrical input (electroacoustic efficiency of 75% at their working frequency) and in vitro and in vivo pig liver tissue destruction. The in vitro and in vivo necroses depth from the applicator surface ranged from 8 to 20 mm. This showed the advantage of a nondivergent source: the pressure decay is only due to the tissue absorption in the Fresnel zone. The lesions dimensions are slightly dependent on perfusion: 8 +/- 2 mm deep in vitro for a 10.7-MHz transducer working at 14 W/cm2 against 10 mm in vivo. Operating at 5 MHz makes it possible to increase the therapeutic heating depth. For example, at a similar close-to-transducer temperature, the 5-MHz applicator induced, at a depth of 10 mm, a temperature elevation of 27 degrees C against 15 degrees C for that working at 10 MHz.
Asunto(s)
Electrocoagulación/instrumentación , Ultrasonido , Animales , Diseño de Equipo , Estudios de Factibilidad , Hipertermia Inducida , Técnicas In Vitro , Hígado/lesiones , Hígado/patología , Masculino , Necrosis , Porcinos , TransductoresRESUMEN
Although interstitial techniques are invasive, they are still the first-line therapeutic modalities for certain types of tumour. They are mainly relevant to tumours that are either inoperable or located so deep that access is complicated. Of the various types of radiation that can be delivered by the interstitial route, ultrasound is the most suitable for deep heating. The study compares the efficacy of two types of applicator with respect to their ability to induce cylindrical zones of coagulation necrosis. The transducer of the first applicator is tubular, whereas the second is plane and can rotate around its axis. Both have an external diameter of 4 mm, are fitted with surface cooling systems and operate at 10.7 MHz and 14 W.cm-2. Comparison involves mathematical modelling of ablated tissue in the targeted area by resolving the bioheat transfer equation (BHTE) using an algorithm based on finite differences. The BHTE gives a temperature value from which the thermal dose can be determined. It is shown that tissue ablation by tubular transducers is slow, and, in consequence, perfusion disturbs the heating pattern: in vivo, irradiation with a tubular transducer lasting 1081 s would be required to ablate a tissue mass with a radius of 8 mm. The corresponding period using a rotating plane transducer with 20 firing angles is only 618 s. The mean exposure time of each shot lasts 31 +/- 7 s. Therefore perfusion would have much less impact in the case of therapy administered using a plane transducer than that using a tubular one.