Agentes hemostáticos tópicos de uso quirúrgico / Topical hemostatic agents for surgical use

Introducción: La morbilidad, mortalidad y costes tras la cirugía se hallan influenciados en gran medida por la pérdida hemática o hemorragia y las consecuencias derivadas de la misma. Para controlar la hemorragia, es frecuente el uso de agentes hemostáticos tópicos en combinación o en adyuvancia a otras técnicas hemostáticas, cuando éstas resultan ineficaces o impracticables. Material y métodos: Se realizó una revisión sistemática en Cochrane y MEDLINE desde el año 2000 a 2017 para identificar las publicaciones relacionadas con el uso de hemostáticos pasivos, activos y sellantes en comparación con otros agentes hemostáticos en todos los tipos de intervenciones quirúrgicas. Resultados: Se seleccionaron 20 ensayos clínicos. La variable principal de eficacia en el 95% fue el tiempo hasta la hemostasia y en el 5% la disminución del sangrado. Las intervenciones quirúrgicas más frecuentes fueron; cirugía hepática (30%), vascular (20%), cardíaca (10%), espinal (10%), general (5%), plástica (5%), y otros tipos de cirugía (20%).Los estudios se dividieron en 7 grupos, en función del tipo de agente hemostático a estudio y el comparador: a) hemostáticos mixtos versus pasivos (10%), b) sellantes de fibrina versus hemostáticos activos (5%), c) sellantes de fibrina versus hemostáticos pasivos (50%), d) hemostáticos mixtos entre sí (15%), e) sellantes de fibrina entre sí (5%), f) hemostáticos pasivos entre sí (5%), g) hemostáticos activos entre sí (10%).Conclusiones: Los hemostáticos activos, mixtos y sellantes de fibrina demuestran superioridad frente a los pasivos en términos de eficacia clínica, con un coste superior y un perfil de efectos adversos similar. (AU)

Introduction: Morbidity, mortality, and costs after surgery are greatly influenced by blood loss or bleeding and the consequences of it.To control bleeding, the use of topical hemostatic agents in combination or adjuvant to other hemostatic techniques is frequent, when these are ineffective or impractical.Method: A systematic review was conducted in Cochrane and PubMed from 2000 to 2017 to identify publications related to the use of passive, active and sealant hemostatics compared to other hemostatic agents in all types of surgical interventions.Results: Twenty clinical trials were selected. The main variable of efficacy in 95% was the time to hemostasis and in 5% the decrease in bleeding.The most frequent surgical interventions were; liver surgery (30%), vascular (20%), cardiac (10%), spinal (10%), general (5%), plastic (5%), and other types of surgery (20%).The studies were divided into 7 groups, depending on the type of hemostatic agent under study and the comparator: a) mixed hemostatic versus passive (10%), b) fibrin sealants versus active hemostatic agents (5%), c) fibrin sealants versus passive hemostatic (50%), d) mixed hemostatic with each other (15%), e) fibrin sealants with each other (5%), f) passive hemostatic with each other (5%), g) active hemostatic with each other (10%).Conclusions: Active and mixed hemostatics and fibrin sealants showed superiority over the passive hemostatics in terms of clinical efficacy, with a higher cost and a similar profile of side effects. (AU)

Strain Modulation of Si Vacancy Emission from SiC Micro- and Nanoparticles.

Single-photon emitting point defects in semiconductors have emerged as strong candidates for future quantum technology devices. In the present work, we exploit crystalline particles to investigate relevant defect localizations, emission shifting, and waveguiding. Specifically, emission from 6H-SiC micro- and nanoparticles ranging from 100 nm to 5 µm in size is collected using cathodoluminescence (CL), and we monitor signals attributed to the Si vacancy (VSi) as a function of its location. Clear shifts in the emission wavelength are found for emitters localized in the particle center and at the edges. By comparing spatial CL maps with strain analysis carried out in transmission electron microscopy, we attribute the emission shifts to compressive strain of 2-3% along the particle a-direction. Thus, embedding VSi qubit defects within SiC nanoparticles offers an interesting and versatile opportunity to tune single-photon emission energies while simultaneously ensuring ease of addressability via a self-assembled SiC nanoparticle matrix.

Clinical significance of epithelial-mesenchymal transition-related markers expression in the micrometastatic sentinel lymph node of NSCLC.

OBJECTIVES: Metastatic lymph node affectation is the main prognostic factor in localised lung cancer. However, the pathological study of lymph nodes reveals tumour relapse for 20% of patients after oncological curative surgery. Recently, EMT (epithelial-mesenchymal transition) has been established as one of the main factors related to lymphatic dissemination and metastasis. This study evaluated the prognostic value of EMT-related gene expression in micrometastatic sentinel lymph nodes (SLN) of non-small cell lung cancer (NSCLC) patients. METHODS: The presence of genes CDH1, CDH2, VIM, TWIST1, SNAI1, SNAI2, ZEB1, and ZEB2 in mRNA was analysed in tumours and in the SLN of NSCLC patients for whom surgery was planned for treatment. The significant association between the expression level of EMT-related markers and patients' clinicopathological characteristics and relapse was assessed. RESULTS: Of the 96 patients, 56 (58.33%) presented molecular micrometastasis in SLN, which showed higher CDH1, CDH2, and VIM expressions than non-micrometastatic ones. An association linking a low CDH1/CDH2 ratio in SLN with molecular micrometastasis, adenocarcinoma, and non-smoking patients was found. The multivariate Cox regression analysis proved the prognostic accuracy of the CDH1/CDH2 ratio in SLN. CONCLUSIONS: The molecular EMT status of SLN could be used as an independent prognosis predictor in early stage NSLCL patients, and as a new tool to better stratify and predict patient outcomes.

Hypereosinophilia and epigastralgia after visiting Tunisia: a rare differential diagnosis of helminthiases.

Causes of hypereosinophilia among travelers returning from North Africa are dominated by helminth infections, especially when associated with gastrointestinal signs. Non-infectious causes must nonetheless be investigated after negative microbiological assessment and failure of a broad empiric antiparasite treatment. We report the case of a young man with epigastralgia and major weight loss since a stay in Tunisia. Empiric treatment with albendazole was not successful. Eosinophilic gastroenteritis was diagnosed and resolved under corticosteroid treatment.

Silicon surface passivation by PEDOT: PSS functionalized by SnO2 and TiO2 nanoparticles.

In this paper, we present a study of silicon surface passivation based on the use of spin-coated hybrid composite layers. We investigate both undoped poly(3,4-ethylenedioxythiophene)/poly-(styrenesulfonate) (PEDOT:PSS), as well as PEDOT:PSS functionalized with semiconducting oxide nanomaterials (TiO2 and SnO2). The hybrid compound was deposited at room temperature by spin coating-a potentially lower cost, lower processing time and higher throughput alternative compared with the commonly used vacuum-based techniques. Photoluminescence imaging was used to characterize the electronic properties of the Si/PEDOT:PSS interface. Good surface passivation was achieved by PEDOT:PSS functionalized by semiconducting oxides. We show that control of the concentration of semiconducting oxide nanoparticles in the polymer is crucial in determining the passivation performance. A charge carrier lifetime of about 275 µs has been achieved when using SnO2 nanoparticles at a concentration of 0.5 wt.% as a filler in the composite film. X-ray diffraction (XRD), scanning electron microscopy, high resolution transmission electron microscopy (HRTEM), energy dispersive x-ray in an SEM, and µ-Raman spectroscopy have been used for the morphological, chemical and structural characterization. Finally, a simple model of a photovoltaic device based on PEDOT:PSS functionalized with semiconducting oxide nanoparticles has been fabricated and electrically characterized.

Topography of the sentinel node according to the affected lobe in lung cancer

Purpose. The objective of this study is to describe the anatomic location of the sentinel lymph node (SLN) of patients with lung carcinoma and to analyze its relationship with the characteristics of the tumor. Patients and methods. 98 Stage I lung cancer patients were included in the study. SLN was marked just after performing the thoracotomy by injecting peritumorally 0.25 mCi of nanocolloid of albumin (Nanocol1) labeled with Tc-99 m in 0.3 ml, and later, it was resected. For SLN micrometastasis analysis, CEACAM5, BPIFA1, and CK7 gene expression at mRNA level was studied. Possible relation between tumor characteristics and SLN location was analyzed. Results. While most of the SLN were located in hilar area, we find a significantly higher number of SLN located in mediastinal stations when the lesion is in the left upper lobe (LUL). This difference disappears in the group of SLN with a positive result in the micrometastasis study. Regarding tumor size, squamous tumors and tumors located in the left lower lobe (LLL) were found significantly larger. Conclusion. The location of the SLN in patients with stage I lung cancer is predominantly hilar, being less consistent in the left hemithorax. The tumor size or histological type is not variables that affect this distribution. The distribution of SLNs with a positive result in the analysis of micrometastasis suggests further spread to the hilar areas when the lesion is in the LUL and to the mediastinal zones when it is in the LLL (AU)

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Topography of the sentinel node according to the affected lobe in lung cancer.

PURPOSE: The objective of this study is to describe the anatomic location of the sentinel lymph node (SLN) of patients with lung carcinoma and to analyze its relationship with the characteristics of the tumor. PATIENTS AND METHODS: 98 Stage I lung cancer patients were included in the study. SLN was marked just after performing the thoracotomy by injecting peritumorally 0.25 mCi of nanocolloid of albumin (Nanocol1) labeled with Tc-99 m in 0.3 ml, and later, it was resected. For SLN micrometastasis analysis, CEACAM5, BPIFA1, and CK7 gene expression at mRNA level was studied. Possible relation between tumor characteristics and SLN location was analyzed. RESULTS: While most of the SLN were located in hilar area, we find a significantly higher number of SLN located in mediastinal stations when the lesion is in the left upper lobe (LUL). This difference disappears in the group of SLN with a positive result in the micrometastasis study. Regarding tumor size, squamous tumors and tumors located in the left lower lobe (LLL) were found significantly larger. CONCLUSION: The location of the SLN in patients with stage I lung cancer is predominantly hilar, being less consistent in the left hemithorax. The tumor size or histological type is not variables that affect this distribution. The distribution of SLNs with a positive result in the analysis of micrometastasis suggests further spread to the hilar areas when the lesion is in the LUL and to the mediastinal zones when it is in the LLL.

Prognostic value of ERCC1, RRM1, BRCA1 and SETDB1 in early stage of non-small cell lung cancer

Introduction: Nowadays, 40 % of early-stage NSCLC patients relapse in the 2 years following resection, suggesting a mis-staging in this group of patients who are not receiving adjuvant chemotherapy. Although different biomarkers, such as ERCC1, RRM1 and BRCA1 have been found to present prognostic value in advanced NSCLC patients, in early-stage NSCLC patients its relevance remains unclear. Moreover, SETDB1 has been recently proposed as a bona fide oncogene in lung tumourigenesis and related with metastasis. The aim of the present study was to analyze the prognostic value of ERCC1, RRM1, BRCA1 and SETDB1 expression levels in NSCLC patients at stage I. Patients and methods: ERCC1, RRM1, BRCA1 and SETDB1 expression at mRNA level was analyzed by realtime quantitative RT-PCR in fresh-frozen tumor and normal adjacent lung tissue samples from 64 stage I NSCLC patients. Later, significant association between gene expression levels, clinicopathological characteristics and patient’s disease-free survival was assessed. Results: We did not find any statistically significant correlation between gene expression and gender, age, histological type or smoking status. Univariate followed by multivariate Cox analysis showed that higher levels of BRCA1 and SETDB1 expression were significantly associated with shorter disease-free survival in stage I NSCLC patients. Conclusion: Our study finds that ERCC1 and RRM1 are not independent prognostic factors of recurrence in stage I NSCLC patients. By contrast, BRCA1 and SETDB1 stand out as the most significant prognostic markers in this group of patients, appearing as promising tools to predict tumor recurrence in early-stage NSCLC patients (AU)

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Prognostic value of ERCC1, RRM1, BRCA1 and SETDB1 in early stage of non-small cell lung cancer.

INTRODUCTION: Nowadays, 40 % of early-stage NSCLC patients relapse in the 2 years following resection, suggesting a mis-staging in this group of patients who are not receiving adjuvant chemotherapy. Although different biomarkers, such as ERCC1, RRM1 and BRCA1 have been found to present prognostic value in advanced NSCLC patients, in early-stage NSCLC patients its relevance remains unclear. Moreover, SETDB1 has been recently proposed as a bona fide oncogene in lung tumourigenesis and related with metastasis. The aim of the present study was to analyze the prognostic value of ERCC1, RRM1, BRCA1 and SETDB1 expression levels in NSCLC patients at stage I. PATIENTS AND METHODS: ERCC1, RRM1, BRCA1 and SETDB1 expression at mRNA level was analyzed by real-time quantitative RT-PCR in fresh-frozen tumor and normal adjacent lung tissue samples from 64 stage I NSCLC patients. Later, significant association between gene expression levels, clinicopathological characteristics and patient's disease-free survival was assessed. RESULTS: We did not find any statistically significant correlation between gene expression and gender, age, histological type or smoking status. Univariate followed by multivariate Cox analysis showed that higher levels of BRCA1 and SETDB1 expression were significantly associated with shorter disease-free survival in stage I NSCLC patients. CONCLUSION: Our study finds that ERCC1 and RRM1 are not independent prognostic factors of recurrence in stage I NSCLC patients. By contrast, BRCA1 and SETDB1 stand out as the most significant prognostic markers in this group of patients, appearing as promising tools to predict tumor recurrence in early-stage NSCLC patients.

Liver function test alterations associated with parenteral nutrition in hospitalized adult patients: incidence and risk factors.

BACKGROUND: Parenteral nutrition-associated liver dysfunction can be progressive and irreversible, particularly in children and patients with long-term treatment. This study has assessed the incidence of abnormal liver function tests in hospitalized adults during short term parenteral nutrition (PN) and has investigated risk factors for developing alterations of each parameter. METHODS: A prospective cohort study of parenteral nutrition treated patients with preserved liver function at baseline. Variables examined included nutritional and clinical data and laboratory parameters. Determinations were performed before starting PN and weekly until liver function test alteration was observed. Risk factors were investigated by four stepwise forward logistical regressions. RESULTS: Eighty patients were included, 57.5% had liver function test alterations. PN mean duration was 15.9 (8-54) days. Mean days with PN and additional enteral/ oral nutrition were 1.5 (0-20). The following associations were found: gamma-glutamyl-transferase increased with soybean lipid intake and absolute diet; alkaline phosphatase increased with septic shock; alanine transaminase increased with septic shock, hyperglycemia and elevated creatinine; total bilirubin increased with septic shock, absolute diet, low prealbumin and glucose, and high creatinine. CONCLUSIONS: The incidence of altered liver function tests is high in adult hospitalized patients treated with short-term PN. However, the effect of nutritional factors in this alteration is low. Oral/enteral nutrition and reduction of soybean lipid supply can reduce increases in some liver function tests such as gamma-glutamyl-transferase and total bilirubin. The high association between all liver function tests and clinical systemic-hypermetabolic variables suggest the importance of specific nutritional strategies for this condition.

Liver function test alterations associated with parenteral nutrition in hospitalized adult patients; incidence and risk factors / Alteraciones de los parámetros hepáticos asociados con la administración de nutrición parenteral en pacientes adultos hospitalizados; incidencia y factores de riesgo

Background: Parenteral nutrition-associated liver dysfunction can be progressive and irreversible, particularly in children and patients with long-term treatment. This study has assessed the incidence of abnormal liver function tests in hospitalized adults during short term parenteral nutrition (PN) and has investigated risk factors for developing alterations of each parameter. Methods: A prospective cohort study of parenteral nutrition treated patients with preserved liver function at baseline. Variables examined included nutritional and clinical data and laboratory parameters. Determinations were performed before starting PN and weekly until liver function test alteration was observed. Risk factors were investigated by four stepwise forward logistical regressions. Results: Eighty patients were included, 57.5% had liver function test alterations. PN mean duration was 15.9 (8-54) days. Mean days with PN and additional enteral/ oral nutrition were 1.5 (0-20). The following associations were found: gamma-glutamyl-transferase increased with soybean lipid intake and absolute diet; alkaline phosphatase increased with septic shock; alanine transaminase increased with septic shock, hyperglycemia and elevated creatinine; total bilirubin increased with septic shock, absolute diet, low prealbumin and glucose, and high creatinine. Conclusions: The incidence of altered liver function tests is high in adult hospitalized patients treated with short-term PN. However, the effect of nutritional factors in this alteration is low. Oral/enteral nutrition and reduction of soybean lipid supply can reduce increases in some liver function tests such as gamma-glutamyl-transferase and total bilirubin. The high association between all liver function tests and clinical systemic-hypermetabolic variables suggest the importance of specific nutritional strategies for this condition (AU)

Introducción: La alteración hepática asociada a la nutrición parenteral (NP) puede ser progresiva e irreversible particularmente en niños y en tratamientos de larga duración. El objetivo de este estudio es establecer la incidencia de las alteraciones de los parámetros hepáticos en pacientes adultos hospitalizados en tratamiento con NP y estudiar los factores de riesgo asociados al desarrollo de las alteraciones de cada uno de los parámetros hepáticos. Métodos: Estudio prospectivo de cohortes de los pacientes tratados con NP con función hepática normal al inicio del tratamiento. Se estudiaron parámetros clínicos, nutricionales y analíticos. Las determinaciones se hicieron antes de iniciar la nutrición y semanalmente hasta que se detectó la alteración de algún parámetro hepático. Los factores de riesgo asociados a la alteración hepática se estudiaron con 4 regresiones logísticas. Resultados: Se incluyeron 80 pacientes y 57,5% mostraron alteraciones hepáticas. La media de duración de la NP fue 15,9 días (8-54) y la media de días con nutrición enteral u oral concomitantes fue de 1,5 (0-20). Se encontraron las siguientes asociaciones: la gamma-glutamil-transferasa aumentaba con la cantidad de lípidos de soja administrados y los días en dieta absoluta; la fosfatasa alcalina con el shock séptico, la alanina-aminotransferasa con el shock séptico, la hiperglucemia y los valores elevados de creatinina; la bilirrubina total con el shock séptico, la dieta absoluta, valores bajos de prealbúmina y glucosa; y valores altos de creatinina. Conclusiones: La incidencia de alteraciones de los parámetros hepáticos es elevada en pacientes adultos hospitalizados tratados con NP, aunque el efecto de los factores nutricionales en esta alteración es bajo. La nutrición oral/enteral y la reducción de los lípidos en forma de soja pueden reducir el aumento de algunos parámetros hepáticos como la gamma-glutamiltransferasa y la bilirrubina total. La gran asociación entre todos los parámetros hepáticos y las variables sistémicas indicadoras de hiper-metabolismo apuntan a la importancia de las estrategias nutricionales específicas en esta situación (AU)

[Giant retroperitoneal hydatid cyst in a traveller]. / Kyste hydatique rétropéritonéal géant chez un voyageur.

INTRODUCTION: Giant hydatid cyst located in the retroperitoneal space is rare. The purpose of this report is to present a case cured by surgery in an adult traveller. CASE REPORT: In August 2009, a 67-year-old female who traveled frequently to Lebanon was admitted for assessment of a giant retroperitoneal hydatid cyst discovered coincidentally following palpation of an abdominal mass in 1997. From 1966 to 1975, the patient had undergone several surgical procedures for pulmonary and hepatic hydatidosis, complicated by vomica and anaphylactic shock. In 1997, computed tomography showed that the retroperitoneal cyst measured 100 mm at the widest point. At that time, the patient refused to undergo further surgery and was treated medically using albendazole initially in association with praziquantel. In 2009, the cyst had expanded to 180 mm at the widest point and the patient finally consented to perikystectomy. Excision was total and recovery was uneventful. Histology examination confirmed the viability of the cyst. Follow-up examination at 12 months indicated no relapse. COMMENTS: The retroperitoneal space is a rare location for hydatidosis. Occurrence in this location is generally primary. In case of discovery of a liquid-filled retroperitoneal mass, a history of travel to an endemic area for hydatid disease should be elicited. Diagnosis relies on radiological findings and positive serology. Since retroperitoneal cysts are often giant, they respond poorly to medical treatment. Similarly radiological treatment is difficult due to retroperitoneal location. Surgery, preferably perikystectomy, is the treatment of choice.

Análisis nosológico con parámetros de perfusión tisular de RM obtenidos mediante los modelos monocompartimental y farmacocinético en los glioblastomas cerebrales / Nosological analysis of MRI tissue perfusion parameters obtained using the unicompartmental and pharmacokinetic models in cerebral glioblastomas

Objetivos. Clasificar las áreas tumorales en pacientes con astrocitoma de grado IV mediante el cálculo y análisis estadístico de parámetros cuantitativos de perfusión por RM. Material y métodos. Se aplicaron 2 modelos de perfusión por RM, monocompartimental y farmacocinético, en 15 pacientes diagnosticados de astrocitoma grado IV. Con el modelo monocompartimental se cuantificó el volumen sanguíneo cerebral (VSC), el tiempo de tránsito medio (TTM) y el flujo sanguíneo cerebral (FSC). Con el farmacocinético se midió la constante de permeabilidad (Ktrans), el coeficiente de extracción (kep), la fracción de volumen del espacio intersticial (ve), la fracción de volumen vascular (vp), la permeabilidad en primer paso (Kfp) y el volumen vascular en primer paso (vpfp). Para cada parámetro se obtuvieron los histogramas del área tumoral total, peritumoral y sana. El análisis estadístico incluyó un análisis de varianza para cada parámetro y un análisis discriminante. Resultados. Las diferencias más significativas entre las regiones se obtuvieron con el VSC, FSC, Ktrans y vpfp, siendo VSC el que mostró mejores resultados. La mejor función clasificatoria mediante análisis discriminante se obtuvo para una combinación de Ktrans y VSC. El análisis de la forma del histograma evidenció diferencias estadísticamente significativas para la curtosis de Ktrans y kep, así como para la asimetría de VSC, FSC, Ktrans y vpfp. Conclusión. El VSC es el parámetro que aisladamente permitió diferenciar mejor entre área tumoral, peritumoral y sana. La función clasificatoria generada a partir de VSC y Ktrans consiguió mejorar estos resultados haciendo más eficaz la clasificación por áreas (AU)

Objectives. To classify the tumor areas in patients with grade IV astrocytoma by calculating and statistically analyzing quantitative MRI perfusion parameters. Material and methods. We applied two models of MRI perfusion, the unicompartmental and the pharmacokinetic models, in 15 patients diagnosed with grade IV astrocytoma. In the unicompartmental model, we quantified cerebral blood volume (CBV), mean transit time (MTT), and cerebral blood flow (CBF). In the pharmacokinetic model, we measured the permeability constant (Ktrans), the extraction coefficient (kep), the fraction of the volume in the interstitial space (ve), the fraction of the volume in the vessels (vp), the permeability in the first pass (Kfp), and the vascular volume in the first pass (vpfp). For each parameter, histograms were obtained for the total tumor area, for the peritumoral area, and for the healthy tissue. The statistical analysis included an analysis of variance for each parameter and a discriminant analysis. Results. The most significant differences between the regions were obtained with CBV, CBF, Ktrans, and vpfp; of these, CBV had the best results. The best classificatory function on the discriminant analysis was the combination of Ktrans and CBV. The analysis of the shape of the histogram showed statistically significant differences for the kurtosis of Ktrans and kep, as well as for the skewness of CBV, CBF, Ktrans, and vpfp. Conclusion. When parameters are considered individually, CBV is the one that best enables differentiation between tumor, peritumoral, and healthy tissue. The classificatory function generated from CBV and Ktrans results in improved classification by areas (AU)

[Nosological analysis of MRI tissue perfusion parameters obtained using the unicompartmental and pharmacokinetic models in cerebral glioblastomas]. / Análisis nosológico con parámetros de perfusión tisular de RM obtenidos mediante los modelos monocompartimental y farmacocinético en los glioblastomas cerebrales.

OBJECTIVES: To classify the tumor areas in patients with grade IV astrocytoma by calculating and statistically analyzing quantitative MRI perfusion parameters. MATERIAL AND METHODS: We applied two models of MRI perfusion, the unicompartmental and the pharmacokinetic models, in 15 patients diagnosed with grade IV astrocytoma. In the unicompartmental model, we quantified cerebral blood volume (CBV), mean transit time (MTT), and cerebral blood flow (CBF). In the pharmacokinetic model, we measured the permeability constant (K(trans)), the extraction coefficient (k(ep)), the fraction of the volume in the interstitial space (v(e)), the fraction of the volume in the vessels (v(p)), the permeability in the first pass (K(fp)), and the vascular volume in the first pass (v(pfp)). For each parameter, histograms were obtained for the total tumor area, for the peritumoral area, and for the healthy tissue. The statistical analysis included an analysis of variance for each parameter and a discriminant analysis. RESULTS: The most significant differences between the regions were obtained with CBV, CBF, K(trans), and v(pfp); of these, CBV had the best results. The best classificatory function on the discriminant analysis was the combination of K(trans) and CBV. The analysis of the shape of the histogram showed statistically significant differences for the kurtosis of K(trans) and k(ep), as well as for the skewness of CBV, CBF, K(trans), and v(pfp). CONCLUSION: When parameters are considered individually, CBV is the one that best enables differentiation between tumor, peritumoral, and healthy tissue. The classificatory function generated from CBV and K(trans) results in improved classification by areas.

Electrical properties of nanostructured tin oxide surfaces produced by thermal treatments.

Sintering SnO2 powder in air or under an oxygen atmosphere at different temperatures, leads to polycrystalline samples with nanostructured surface as revealed by atomic force microscopy (AFM). The thermal treatments are also responsible for the variation of the surface electrical properties, as studied by scanning spreading resistance microscopy (SSRM) and scanning tunnelling microscopy and spectroscopy (STM-STS). The surface presents a p-conductance, contrary to the n-type characteristic of the bulk, and a band gap lower than the bulk band gap (3.6 eV). The electrical behaviour at the grain boundaries and the role of oxygen are discussed. X-ray photoelectron spectroscopy (XPS) results show a higher presence of oxygen at the boundaries, which generates a shift of the Fermi level position (E(F)-E(V)) towards lower energies.

The novel immunosuppressive enzyme IL4I1 is expressed by neoplastic cells of several B-cell lymphomas and by tumor-associated macrophages.

We previously reported a strong IL4I1 gene expression in primary mediastinal B-cell lymphoma (PMBL) and recently identified the protein as a secreted L-phenylalanine oxidase, physiologically expressed by myeloid cells, which inhibits T-cell proliferation in vitro. Here, we analyzed the pattern of IL4I1 protein expression in 315 human lymphoid and non-lymphoid malignancies. Besides PMBL, IL4I1 expression in tumors was very frequent. IL4I1 was detected in tumor-associated macrophages from most of the tumors and in neoplastic cells from follicular lymphoma, classic and nodular lymphocyte predominant Hodgkin lymphomas and small lymphocytic lymphoma, three of which are germinal center derived. IL4I1-positive tumor cells were also detected in rare cases of solid cancers, mainly mesothelioma. The enzymatic activity paralleled protein expression, suggesting that IL4I1 is functional in vivo. Depending on the tumor type, IL4I1 may impact on different infiltrating lymphocyte populations with consequences on tumor evolution. In the particular case of follicular lymphoma cells, which are susceptible to antitumor cytotoxic T cells killing but depend on interactions with local T helper cells for survival, a high level of IL4I1 expression seems associated with the absence of bone marrow involvement and a better outcome. These findings plead for an evaluation of IL4I1 as a prognosis factor.

Transcriptomic analysis of polyamine-related genes and polyamine levels in placenta, yolk sac and fetus during the second half of mouse pregnancy.

In mammals, polyamines are essential for the maintenance of cell growth. Although early studies reported the highest values of mammalian ornithine decarboxylase (ODC) activity, a key enzyme in polyamine biosynthesis, in rodent placenta, the role of this enzyme in the second half of rodent pregnancy is still controversial. In order to get new insights on polyamine metabolism during this period of pregnancy, we studied polyamine levels, ODC expression and activity and transcript profile of different polyamine-related genes in mouse placenta, fetus and yolk sac. Results indicated that ODC activity and protein levels were higher in placenta than in fetus and yolk sac, especially in the labyrinth, although no correlation between ODC activity and polyamine levels were observed. The half-life of placental ODC ( approximately 190 min) was also higher than the fetal one ( approximately 24 min). Messenger RNAs of all biosynthetic and retroconversion enzymes of polyamine metabolism were present in the three gestational compartments analyzed, as well as those of antizymes 1 and 2 and antizyme inhibitor 1. However, no expression of antizyme 3 and antizyme inhibitor 2 was detected. The catabolic enzyme diamine oxidase was expressed only in the maternal part of placenta but not in the fetal part or in the fetus. The expansion of polyamine pools in the fetus was markedly higher than in placenta, in spite of its lower biosynthetic activity. Our results suggest that the elevated polyamine biosynthetic activity of mouse placenta is required to satisfy the high demand of polyamines required by the growing fetus, during the later period of pregnancy.

[Late mediastinal metastasis of Ewing's sarcoma of tibia]. / Métastase médiastinale tardive d'un sarcome d'Ewing du tibia.

Peripheral neuroectodermal tumors constitute a large spectrum of small round cell tumors among which Ewing's sarcoma is the most undifferentiated type. They are rare tumors which often concern young people and generally occur in bone tissue. Their metastatic potential is high, generally early, and rarely after five years. We report the case of a 45-year-old woman who presented a mediastinal metastasis eight years after the primitive tumor of tibia. The diagnosis was made on small core biopsies obtained by CT punction, and was based on morphologic analysis, immunohistochemistry, and confirmed by molecular biology. The presence of metastasis is the main prognostic factor. Despite therapeutic progress, the global survival rate of metastatic patients is still poor.

Cathodoluminescence study of semiconductor oxide micro- and nanostructures grown by vapor deposition.

Nano- and microstructures of SnO(2), In(2)O(3) and ZnO have been grown during thermal treatment of compacted powders under argon flow. Indium-doped SnO(2) tube-shaped structures with rectangular cross-section are obtained by adding a fraction of In(2)O(3) to the starting SnO(2) powder. In-rich nanoislands were found to grow on some edges of the tubes. ZnO nanostructures doped with Sn or Eu were grown by adding SnO(2) and Eu(2)O(3) powder, respectively, to the ZnO precursor powder. All the samples have been characterized by the emissive and cathodoluminescence (CL) modes of scanning electron microscopy. CL images from SnO(2):In and In(2)O(3):Sn tubes and islands show a higher emission from the Sn-rich structures related to oxygen deficiency. CL of doped ZnO enables to detect the presence of dopant in specific regions or structures. CL appears to be a useful technique to study optical and electronic properties of semiconductor oxide nanostructures.

Growth and luminescence of N doped TiO2 nanowires.

Titanium oxide nanowires have been grown by thermal treatment of pressed TiN powder under argon or N2 flow. It has been found that two-step treatments at two different temperatures, 400 degrees C and 800 degrees C, lead to the growth of nanowires all over the sample surface. The nanowires are of single crystalline rutile structure. Energy dispersive X-ray spectroscopy and photoelectron spectroscopy measurements show that the oxide nanostructures contain N from the starting nitride. The mechanism of N incorporation into the oxide and its possible effect on the luminescence are discussed.