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1.
Nano Lett ; 20(12): 8689-8695, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33175553

RESUMO

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.

2.
Clin Transl Oncol ; 22(3): 381-391, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31134511

RESUMO

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.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Transição Epitelial-Mesenquimal/genética , Neoplasias Pulmonares/patologia , Linfonodo Sentinela/patologia , Idoso , Antígenos CD/genética , Antígenos CD/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Caderinas/genética , Caderinas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Metástase Linfática , Masculino , Micrometástase de Neoplasia , Prognóstico , Linfonodo Sentinela/metabolismo , Biópsia de Linfonodo Sentinela
3.
Med Sante Trop ; 28(3): 334-336, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30270843

RESUMO

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.


Assuntos
Enterite/diagnóstico , Eosinofilia/diagnóstico , Gastrite/diagnóstico , Helmintíase/diagnóstico , Doença Relacionada a Viagens , Adulto , Diagnóstico Diferencial , Enterite/complicações , Enterite/parasitologia , Eosinofilia/complicações , Eosinofilia/parasitologia , Gastrite/complicações , Gastrite/parasitologia , Helmintíase/complicações , Humanos , Masculino , Dor/etiologia , Tunísia
4.
Nanotechnology ; 29(3): 035401, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29176063

RESUMO

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.

5.
Clin Transl Oncol ; 19(7): 858-864, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28130707

RESUMO

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.


Assuntos
Adenocarcinoma/secundário , Carcinoma Pulmonar de Células não Pequenas/secundário , Carcinoma de Células Escamosas/secundário , Neoplasias Pulmonares/patologia , Linfonodos/patologia , Adenocarcinoma/cirurgia , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Carcinoma de Células Escamosas/cirurgia , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/cirurgia , Linfonodos/cirurgia , Masculino , Pessoa de Meia-Idade , Micrometástase de Neoplasia , Estadiamento de Neoplasias , Biópsia de Linfonodo Sentinela
6.
Clin Transl Oncol ; 18(8): 798-804, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26542178

RESUMO

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.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Recidiva Local de Neoplasia/patologia , Adulto , Idoso , Proteína BRCA1/análise , Proteína BRCA1/biossíntese , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Proteínas de Ligação a DNA/análise , Proteínas de Ligação a DNA/biossíntese , Intervalo Livre de Doença , Endonucleases/análise , Endonucleases/biossíntese , Feminino , Histona-Lisina N-Metiltransferase , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/mortalidade , Prognóstico , Modelos de Riscos Proporcionais , Proteínas Metiltransferases/análise , Proteínas Metiltransferases/biossíntese , Reação em Cadeia da Polimerase em Tempo Real , Ribonucleosídeo Difosfato Redutase , Proteínas Supressoras de Tumor/análise , Proteínas Supressoras de Tumor/biossíntese
7.
Nutr Hosp ; 27(4): 1279-85, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23165574

RESUMO

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.


Assuntos
Hepatopatias/epidemiologia , Testes de Função Hepática , Fígado/fisiologia , Nutrição Parenteral/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Hospitalização , Humanos , Incidência , Tempo de Internação , Hepatopatias/etiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
8.
Med Trop (Mars) ; 71(1): 7-10, 2011 Feb.
Artigo em Francês | MEDLINE | ID: mdl-21585080

RESUMO

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.


Assuntos
Equinococose , Viagem , Idoso , Equinococose/diagnóstico , Equinococose/cirurgia , Feminino , Humanos , Espaço Retroperitoneal
9.
Radiologia ; 52(5): 432-41, 2010.
Artigo em Espanhol | MEDLINE | ID: mdl-20655078

RESUMO

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.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/fisiopatologia , Glioblastoma/diagnóstico , Glioblastoma/fisiopatologia , Angiografia por Ressonância Magnética , Adulto , Idoso , Circulação Cerebrovascular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
Leukemia ; 23(5): 952-60, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19436310

RESUMO

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.


Assuntos
L-Aminoácido Oxidase/metabolismo , Linfoma de Células B/enzimologia , Macrófagos/enzimologia , Neoplasias/enzimologia , Células Neoplásicas Circulantes/patologia , Linfócitos B/enzimologia , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática , Feminino , Centro Germinativo/enzimologia , Centro Germinativo/patologia , Humanos , Técnicas Imunoenzimáticas , Linfoma de Células B/patologia , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Células Tumorais Cultivadas
11.
J Nanosci Nanotechnol ; 9(3): 1772-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19435039

RESUMO

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.

12.
Placenta ; 30(3): 241-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19131104

RESUMO

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.


Assuntos
Feto/metabolismo , Placenta/metabolismo , Poliaminas/metabolismo , Prenhez/metabolismo , Saco Vitelino/metabolismo , Animais , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Imuno-Histoquímica , Camundongos , Ornitina Descarboxilase/metabolismo , Gravidez , Prenhez/genética
13.
Rev Pneumol Clin ; 64(3): 133-6, 2008 Jun.
Artigo em Francês | MEDLINE | ID: mdl-18656786

RESUMO

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.


Assuntos
Neoplasias Ósseas/patologia , Neoplasias do Mediastino/diagnóstico , Neoplasias do Mediastino/secundário , Sarcoma de Ewing/diagnóstico , Sarcoma de Ewing/secundário , Tíbia , Neoplasias Ósseas/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Neoplasias do Mediastino/diagnóstico por imagem , Neoplasias do Mediastino/patologia , Pessoa de Meia-Idade , Prognóstico , Radiografia , Sarcoma de Ewing/diagnóstico por imagem , Sarcoma de Ewing/patologia
14.
Scanning ; 30(4): 354-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18512700

RESUMO

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.

15.
J Nanosci Nanotechnol ; 8(12): 6533-7, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19205236

RESUMO

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.

16.
Br J Dermatol ; 154(3): 478-84, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16445779

RESUMO

BACKGROUND: Melanotic pigmentations in scars consecutive to the excision of melanocytic tumours can be secondary to a reactive phenomenon related to the scar tissue or to a recurrence of the melanocytic lesion excised in the first case. Recurrent naevi may sometimes adopt unusual features that make them difficult to differentiate from a melanoma. OBJECTIVES: To describe the clinical, dermoscopic and histological features of melanotic pigmentations in scars consecutive to the excision of melanocytic tumours, and to correlate the histological diagnosis with the dermoscopic features. METHODS: This was a prospective cohort study using macrophotography, dermoscopy and histopathological study. Ninety-five melanotic pigmentations (77 patients) in scars secondary to the excision of melanocytic tumours were prospectively collected in the Department of Dermatology at the Instituto Valenciano de Oncología in Valencia, Spain. Histopathological study was performed in 57 scars. RESULTS: Thirteen dermoscopic structures were identified. Four criteria allowed a differentiation between reactive and specific melanocytic pigmentations. Presence of globules and presence of heterogeneous pigmentation were features associated with specific melanocytic pigmentations (P < 0.0001). Presence of a regular network and presence of streaks were more frequently found in reactive pigmentations (P = 0.023 and 0.026, respectively). CONCLUSIONS: Dermoscopic examination of melanotic pigmentations in excision scars of melanocytic tumours provides useful information about the origin of that pigmentation. Based on such information, recurrent naevi can be differentiated from reactive pigmentations in most cases. Excision and histopathological diagnosis continue to be imperative in some cases of recurrent naevi with atypical clinical features.


Assuntos
Melanoma/cirurgia , Melanose/diagnóstico , Recidiva Local de Neoplasia/diagnóstico , Nevo Pigmentado/cirurgia , Neoplasias Cutâneas/cirurgia , Cicatriz/etiologia , Cicatriz/patologia , Dermoscopia , Diagnóstico Diferencial , Humanos , Melanoma/diagnóstico , Melanoma/patologia , Melanose/etiologia , Melanose/patologia , Recidiva Local de Neoplasia/patologia , Nevo Pigmentado/diagnóstico , Nevo Pigmentado/patologia , Estudos Prospectivos , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia
17.
Nanotechnology ; 17(6): 1584-8, 2006 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-26558563

RESUMO

Samples of rutile TiO2 have been prepared by sintering compacted powders under argon flow. Long (above 20 h) sintering times at 1500 °C led to the formation of rods with squared cross-sections in a broad range of sizes. A two-step annealing treatment, at two temperatures, was found to favour the growth of low-dimensional elongated structures as well as a terraced structure on the grain surface, producing samples with high surface to volume ratio. The cathodoluminescence (CL) spectrum of the initial powder, shows an emission centred at about 2.40 eV, which can be separated into three Gaussian bands at 2.19, 2.30 and 2.55 eV. The main features of the CL spectra of sintered samples are an infrared band at 1.52 eV and a complex band in the visible range, whose peak position shifts with the annealing temperature. In samples sintered for 30 h an emission at 1.80 eV appears, while the dominant emission at 1.52 eV, due to titanium interstitials, is quenched.

18.
J Eur Acad Dermatol Venereol ; 19(1): 90-2, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15649199

RESUMO

A 60-year-old woman presented with a pigmented lesion on the upper left gingival mucosa of 2 years duration. The lesion was in an area where a dental metallic prosthesis had been inserted into a nearby tooth several years earlier. A biopsy of the affected mucosa showed aggregates of pigmented granules varying in size in the dermis, extracellular matrix and within macrophages; these did not stain with melanin stains. The diagnosis was consistent with an amalgam tattoo.


Assuntos
Amálgama Dentário/efeitos adversos , Prótese Dentária/efeitos adversos , Mucosa Bucal/patologia , Transtornos da Pigmentação/diagnóstico , Transtornos da Pigmentação/etiologia , Biópsia , Diagnóstico Diferencial , Feminino , Humanos , Doença Iatrogênica , Pessoa de Meia-Idade
19.
J Endocrinol ; 183(2): 343-51, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15531722

RESUMO

Feeding mice an arginine-deficient diet decreased plasma concentrations of arginine, citrulline and ornithine in the females and arginine in the males, abolishing the sexual dimorphic pattern of these amino acids found in mice fed the standard diet. In addition, the restriction of dietary arginine produced a marked decrease in body and renal weights as well as in the activity of renal ornithine decarboxylase, decreases that were gender dependent since they were observed exclusively in males. The fact that these changes were not associated with the decrease in the circulating levels of testosterone and that the dietary arginine restriction prevented the body weight gain induced by testosterone treatment of female mice fed the standard diet indicates that dietary arginine is required for the anabolic action of androgens. Moreover, under certain conditions that could compromise the renal synthesis of arginine, as in the compensatory renal hypertrophy that follows unilateral nephrectomy, the myotrophic effect of testosterone was transiently impaired. The results also revealed that arginine deficiency produced an opposite effect in the expression of IGF-I and IGF-binding protein 1 in the liver and kidney. Taken together, our results indicate that dietary arginine may be relevant to the anabolic action of testosterone, and suggest that this effect may be mediated by changes in the insulin-like growth factor system.


Assuntos
Androgênios/metabolismo , Arginina/metabolismo , Dieta , Animais , Sequência de Bases , Feminino , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Fator de Crescimento Insulin-Like I/genética , Rim/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos , Dados de Sequência Molecular , Ornitina Descarboxilase/metabolismo , RNA Mensageiro/análise , Receptor IGF Tipo 1/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Caracteres Sexuais , Aumento de Peso
20.
Amino Acids ; 26(1): 53-8, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14752616

RESUMO

The aminoacyl-imidazole dipeptides carnosine (beta-alanyl-L-histidine) and anserine (beta-alanyl-1-methyl-histidine) are present in relatively high concentrations in excitable tissues, such as muscle and nervous tissue. In the present study we describe the existence of a marked sexual dimorphism of carnosine and anserine in skeletal muscles of CD1 mice. In adult animals the concentrations of anserine were higher than those of carnosine in all skeletal muscles studied, and the content of aminoacyl-imidazole dipeptides was remarkably higher in males than in females. Postnatal ontogenic studies and hormonal manipulations indicated that carnosine synthesis was up-regulated by testosterone whereas anserine synthesis increased with age. Regional variations in the concentrations of the dipeptides were observed in both sexes, skeletal muscles from hind legs having higher amounts of carnosine and anserine than those present in fore legs or in the pectoral region. The concentration of L-lysine in skeletal muscles also showed regional variations and a sexual dimorphic pattern with females having higher levels than males in all muscles studied. The results suggest that these differences may be related with the anabolic action of androgens on skeletal muscle.


Assuntos
Anserina/química , Carnosina/química , Lisina/química , Músculo Esquelético/química , Fatores Etários , Animais , Feminino , Masculino , Camundongos , Fatores Sexuais
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