RESUMO
Correlative analysis is a powerful way to relate crystallographic and chemical information to the properties of materials. In this work, a procedure is proposed to select and analyze interfaces of polycrystalline thin film materials through correlative transmission Kikuchi diffraction/energy dispersive X-ray spectroscopy (TKD/EDS), transmission electron microscopy (TEM) and atom probe tomography (APT). TKD provides information on the crystallographic orientation. The EDS analysis performed together with TKD in the scanning electron microscope (SEM) makes chemical information available allowing phases of similar crystal structure, but with a different composition to be distinguished. The information of TKD/EDS can be correlated to successive TEM and APT analysis on selected interfaces for structural and chemical analysis at the atomic scale. An interface of an epitaxial orientated grain of a polycrystalline CoSi2 thin film on (111)Si is selected and analyzed. The selected interface has a twin character and shows facets of different orientation and area. Site-specific segregation of Ge to junctions of the facets is evidenced. The correlation between local strain from misfit (defects) at the interface and segregation is discussed.
RESUMO
PURPOSE: Rhabdomyosarcoma (RMS), the most common soft-tissue sarcoma in childhood, rarely affects adults, preferring male. RMS expresses the receptor for androgen (AR) and responds to androgen; however, the molecular action of androgens on RMS is unknown. METHODS: Herein, testosterone (T) effects were tested in embryonal (ERMS) and alveolar (ARMS) RMS cell lines, by performing luciferase reporter assay, RT-PCR, and western blotting experiments. RNA interference experiments or bicalutamide treatment was performed to assess the specific role of AR. Radiation treatment was delivered to characterise the effects of T treatment on RMS intrinsic radioresistance. RESULTS: Our study showed that RMS cells respond to sub-physiological levels of T stimulation, finally promoting AR-dependent genomic and non-genomic effects, such as the transcriptional regulation of several oncogenes, the phosphorylation-mediated post-transductional modifications of AR and the activation of ERK, p38 and AKT signal transduction pathway mediators that, by physically complexing or not with AR, participate in regulating its transcriptional activity and the expression of T-targeted genes. T chronic daily treatment, performed as for the hormone circadian rhythm, did not significantly affect RMS cell growth, but improved RMS clonogenic and radioresistant potential and increased AR mRNA both in ERMS and ARMS. AR protein accumulation was evident in ERMS, this further developing an intrinsic T-independent AR activity. CONCLUSIONS: Our results suggest that androgens sustain and improve RMS transformed and radioresistant phenotype, and therefore, their therapeutic application should be avoided in RMS post puberal patients.
Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Rabdomiossarcoma/metabolismo , Transdução de Sinais/fisiologia , Testosterona/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Rabdomiossarcoma/patologia , Transdução de Sinais/efeitos dos fármacosRESUMO
Over the years, advances in immunohistochemistry techniques have been a critical step in detecting and mapping neuromodulatory substances in the central nervous system. The better quality and specificity of primary antibodies, new staining procedures and the spectacular development of imaging technologies have allowed such progress. Very recently, new methods permitting tissue transparency have been successfully used on brain tissues. In the present study, we combined whole-mount immunostaining for tyrosine hydroxylase (TH), oxytocin (OXT) and arginine vasopressin (AVP), with the iDISCO+ clearing method, light-sheet microscopy and semi-automated counting of three-dimensionally-labelled neurones to obtain a (3D) distribution of these neuronal populations in a 5-day postnatal (P5) mouse brain. Segmentation procedure and 3D reconstruction allowed us, with high resolution, to map TH staining of the various catecholaminergic cell groups and their ascending and descending fibre pathways. We show that TH pathways are present in the whole P5 mouse brain, similar to that observed in the adult rat brain. We also provide new information on the postnatal distribution of OXT and AVP immunoreactive cells in the mouse hypothalamus, and show that, compared to AVP neurones, OXT neurones in the supraoptic (SON) and paraventricular (PVN) nuclei are not yet mature in the early postnatal period. 3D semi-automatic quantitative analysis of the PVN reveals that OXT cell bodies are more numerous than AVP neurones, although their immunoreactive soma have a volume half smaller. More AVP nerve fibres compared to OXT were observed in the PVN and the retrochiasmatic area. In conclusion, the results of the present study demonstrate the utility and the potency of imaging large brain tissues with clearing procedures coupled to novel 3D imaging technologies to study, localise and quantify neurotransmitter substances involved in brain and neuroendocrine functions.
Assuntos
Encéfalo/citologia , Neurônios/citologia , Ocitocina/análise , Tirosina 3-Mono-Oxigenase/análise , Vasopressinas/análise , Animais , Encéfalo/metabolismo , Feminino , Imageamento Tridimensional , Imuno-Histoquímica , Masculino , Camundongos Endogâmicos C57BL , Neurônios/metabolismoRESUMO
The issue of intensive and palliative care in patients with chronic disease frequently arises. This review aims to describe the prognostic factors of chronic respiratory diseases in stable and in acute situations in order to improve the management of these complex situations. The various laws on patients' rights provide a legal framework and define the concept of unreasonable obstinacy. For patients with chronic obstructive pulmonary disease, the most robust decision factors are good knowledge of the respiratory disease, the comorbidities, the history of previous exacerbations and patient preferences. In the case of idiopathic pulmonary fibrosis, it is necessary to know if there is a prospect of transplantation and to assess the reversibility of the respiratory distress. In the case of amyotrophic lateral sclerosis, treatment decisions depend on the presence of advance directives about the use of intubation and tracheostomy. For lung cancer patients, general condition, cancer history and the tumor treatment plan are important factors. A multidisciplinary discussion that takes into account the patient's medical history, wishes and the current state of knowledge permits the taking of a coherent decision.
Assuntos
Cuidados Críticos/estatística & dados numéricos , Cuidados Paliativos/métodos , Transtornos Respiratórios/complicações , Transtornos Respiratórios/terapia , Doença Crônica , Tomada de Decisões , Humanos , Conforto do Paciente/métodos , Prognóstico , Transtornos Respiratórios/diagnósticoRESUMO
Childhood neuroblastic tumors are characterized by heterogeneous clinical courses, ranging from benign ganglioneuroma (GN) to highly lethal neuroblastoma (NB). Although a refined prognostic evaluation and risk stratification of each tumor patient is becoming increasingly essential to personalize treatment options, currently only few biomolecular markers (essentially MYCN amplification, chromosome 11q status and DNA ploidy) are validated for this purpose in neuroblastic tumors. Here we report that Galectin-3 (Gal-3), a ß-galactoside-binding lectin involved in multiple biological functions that has already acquired diagnostic relevance in specific clinical settings, is variably expressed in most differentiated and less aggressive neuroblastic tumors, such as GN and ganglioneuroblastoma, as well as in a subset of NB cases. Gal-3 expression is associated with the INPC histopathological categorization (P<0.001) and Shimada favorable phenotype (P=0.001), but not with other prognostically relevant features. Importantly, Gal-3 expression was associated with a better 5-year overall survival (P=0.003), and with improved cumulative survival in patient subsets at worse prognosis, such as older age at diagnosis, advanced stages or NB histopathological classification. In vitro, Gal-3 expression and nuclear accumulation accompanied retinoic acid-induced cell differentiation in NB cell lines. Forced Gal-3 overexpression increased phenotypic differentiation and substrate adherence, while inhibiting proliferation. Altogether, these findings suggest that Gal-3 is a biologically relevant player for neuroblastic tumors, whose determination by conventional immunohistochemistry might be used for outcome assessment and patient's risk stratification in the clinical setting.
Assuntos
Biomarcadores Tumorais/metabolismo , Galectina 3/metabolismo , Ganglioneuroma/metabolismo , Neuroblastoma/metabolismo , Adolescente , Apoptose , Biomarcadores Tumorais/genética , Proteínas Sanguíneas , Adesão Celular , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Criança , Pré-Escolar , Feminino , Galectina 3/genética , Galectinas , Ganglioneuroblastoma/metabolismo , Ganglioneuroblastoma/patologia , Ganglioneuroma/genética , Ganglioneuroma/mortalidade , Ganglioneuroma/patologia , Humanos , Imuno-Histoquímica , Lactente , Recém-Nascido , Estimativa de Kaplan-Meier , Masculino , Estadiamento de Neoplasias , Neuroblastoma/genética , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Valor Preditivo dos Testes , Fatores de Risco , Fatores de Tempo , TransfecçãoRESUMO
BACKGROUND: Cure rate for subjects with refractory or relapsing metastatic neuroblastoma is <5%. In the search for a novel therapy, continuous daily oral administration of imatinib mesylate was evaluated. PATIENTS AND METHODS: Twenty-four subjects were enrolled in a two-stage study. Imatinib was administered for the first 4 weeks (cycle) at 170 mg/sqm b.i.d. If no major toxicity occurred, the dose was escalated to 300 mg/sqm b.i.d. for a maximum of 12 cycles. Clinical response and toxicity were evaluated according to international criteria. Pharmacokinetics (PK) profiles and tyrosine hydroxylase (TH) mRNA expression were also determined in a subset of subjects. RESULTS: Five (21%) complete responses, with one subject still alive at 68 months, and 2 (8%) partial responses lasting up to 29 months were obtained. No grade 4 toxicity was observed. At steady-state, PK exposure (69.7 µg h/ml) was similar to that of adults receiving 1000 mg/die. Responses appear to correlate with the absence or presence of metastasis in the bone marrow (BM) alone, with low TH expression levels at study entry and low imatinib exposure. CONCLUSIONS: Imatinib mesylate was well-tolerated and effective in the subset of subjects with low BM infiltration as only site of metastasis. Study identifier EudraCT: 2005-005778-63.
Assuntos
Antineoplásicos/uso terapêutico , Benzamidas/uso terapêutico , Neoplasias da Medula Óssea/secundário , Neuroblastoma/tratamento farmacológico , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Adolescente , Antineoplásicos/efeitos adversos , Benzamidas/administração & dosagem , Benzamidas/efeitos adversos , Criança , Pré-Escolar , Esquema de Medicação , Feminino , Humanos , Mesilato de Imatinib , Estudos Longitudinais , Masculino , Recidiva Local de Neoplasia , Neuroblastoma/secundário , Piperazinas/administração & dosagem , Piperazinas/efeitos adversos , Pirimidinas/administração & dosagem , Pirimidinas/efeitos adversos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Tirosina 3-Mono-Oxigenase/genéticaAssuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Dexametasona/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Homeodomínio/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Receptor Notch1/antagonistas & inibidores , Receptores de Glucocorticoides/metabolismo , Anti-Inflamatórios/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/antagonistas & inibidores , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Western Blotting , Imunoprecipitação da Cromatina , Proteínas de Homeodomínio/antagonistas & inibidores , Proteínas de Homeodomínio/genética , Humanos , Mutação/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptor Notch1/genética , Receptor Notch1/metabolismo , Receptores de Glucocorticoides/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição HES-1 , Células Tumorais CultivadasRESUMO
The synthesis protocol for Ge-imogolite (aluminogermanate nanotubes) consists of 3 main steps: base hydrolysis of a solution of aluminum and germanium monomers, stabilization of the suspension and heating at 95 °C. The successful synthesis of these nanotubes was found to be sensitive to the hydrolysis step. The impact of the hydrolysis ratio (from n(OH)/n(Al) = 0.5 to 3) on the final product structure was examined using a combination of characterization tools. Thus, key hydrolysis ratios were identified: n(OH)/n(Al) = 1.5 for the formation of nanotubes with structural defects, n(OH)/n(Al) = 2 for the synthesis of a well crystallized Ge imogolite and n(OH)/n(Al) > 2.5 where nanotube formation is hindered. The capability of controlling the degree of the nanotube's crystallinity opens up interesting opportunities in regard to new potential applications.
Assuntos
Neuroblastoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Criança , Diagnóstico por Imagem , Predisposição Genética para Doença , Humanos , Regressão Neoplásica Espontânea , Estadiamento de Neoplasias , Neoplasia Residual/terapia , Neuroblastoma/tratamento farmacológico , Neuroblastoma/epidemiologia , Neuroblastoma/patologia , Neuroblastoma/radioterapia , Neuroblastoma/cirurgia , Guias de Prática Clínica como Assunto , Prognóstico , Fatores de RiscoRESUMO
Multiple defects in apoptotic pathways have been described in peripheral neuroblastic tumours (NTs). Mitosis-karyorrhexis index (MKI) is a reliable morphological marker identifying favourable and unfavourable NTs. The extent to which apoptotic processes contribute to determine the clinical significance of MKI is still undefined. Apoptosis was investigated in a series of 110 peripheral NTs by comparing MKI to immunohistochemical and molecular apoptotic features. High MKI was found in 55 out of 110 NTs (50%) and was associated with advanced stage (P = 0.007), neuroblastoma (NB) histological category (P = 0.024), MYCN amplification (P < 0.001), and poor outcome (P = 0.011). Overall survival probability was 45% in patients with high MKI compared to 73% in patients with low MKI. In the same 110 NTs, the expression of Bcl-2, Bcl-XL, Bax and Mcl-1 was studied by immunohistochemistry, but no significant associations were found with clinicohistological features. Microarray analysis of apoptotic genes was performed in 40 out of 110 representative tumours. No significant association was found between the expression of apoptotic genes and MKI or clinicohistological features. Proliferative activity was assessed in 60 out of 110 representative tumours using Ki67 immunostaining, but no significant correlations with MKI or clinicobiological features were found. In NTs, the combination of apoptosis and proliferation as expressed by MKI is a significant prognostic parameter, although neither of them is per se indicative of the clinicobiological behaviour and outcome.
Assuntos
Apoptose , Neuroblastoma/diagnóstico , Neuroblastoma/metabolismo , Neoplasias do Sistema Nervoso Periférico/diagnóstico , Neoplasias do Sistema Nervoso Periférico/metabolismo , Adolescente , Biomarcadores Tumorais/biossíntese , Proliferação de Células , Criança , Pré-Escolar , Feminino , Perfilação da Expressão Gênica , Humanos , Lactente , Recém-Nascido , Masculino , Índice Mitótico , Neuroblastoma/genética , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias do Sistema Nervoso Periférico/genética , Valor Preditivo dos Testes , Prognóstico , Análise de SobrevidaRESUMO
PURPOSE: We report the off-label study aimed at investigating the use of temozolomide (TMZ) as single agent in relapsed or resistant pediatric solid tumors. The drug was administered at the dose of 215 mg/m2/day x 5 days or 180 mg/m2/day x 5 days in patients with prior craniospinal irradiation (CSI) or autologous bone marrow transplantation (ABMT). PATIENTS AND METHODS: Fifty two patients, median age 127.6 months, with resistant or relapsed solid tumors were enrolled. Tumor types were: neuroblastoma (NB; n = 17), medulloblastoma (MB; 8), brain stem glioma (BSG; 8), extraosseous Ewing's sarcoma/peripheral neuroectodermal tumor (EOES; 4), Ewing's sarcoma (ES; 4), anaplastic astrocytoma (AA; 3), rhabdomyosarcoma (RMS; 2), ependymoma (EP; 2), cerebral primitive neuroectodermal tumor (cPNET; 2), hepatocarcinoma (HC; 1), and osteosarcoma (OS; 1). All patients were pre-treated. Two outpatient courses were administered, with a median of 4.8 courses/pt. RESULTS: Objective response-rate (CR + PR + MR) in our series was 13.4% (1.9% CR, 3.8% PR, and 7.7% MR), SD occurred in 38.4% of patients and 48% had PD. The median survival was 7.8 months (range 1-37) and median time to progression was 3.4 months (range 1-20); these data were significantly correlated with histology and previous nitrosureas administration in multivariate analysis. Haematological toxicity grade 3-4 (mainly thrombocytopenia) was observed in 21.4% of administered courses, nausea was reported in 3.1% and respiratory distress in 0.7%. CONCLUSION: Oral TMZ was well tolerated in children with resistant or relapsed solid tumors and showed activity in NB and CNS tumours refractory to standard chemotherapy.
Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Dacarbazina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias/tratamento farmacológico , Adolescente , Adulto , Antineoplásicos Alquilantes/efeitos adversos , Criança , Pré-Escolar , Dacarbazina/efeitos adversos , Dacarbazina/uso terapêutico , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Neoplasias/patologia , Análise de Sobrevida , TemozolomidaRESUMO
Children affected by advanced neuroblastoma have a discouraging prognosis, but intensive induction chemotherapy may increase the complete response rate. The combination of ifosfamide, carboplatin and etoposide (ICE) was used for the first time as front-line regimen in patients with stage 4 neuroblastoma over the age of 1 y. Similarly, second-line treatment for children with relapsed neuroblastoma, particularly after high-dose chemotherapy, has been unsatisfactory. The combination of topotecan and cyclophosphamide was studied in resistant or relapsed solid tumors. Furthermore, there is a need for effective palliative treatment in patients failing therapy. Temozolomide, a new dacarbazine analog with optimal oral bioavailability, is being used in an ongoing phase II study as an alternative to oral etoposide. Seventeen patients with stage 4 neuroblastoma have entered the ICE study; 15/16 (94%) major responses after induction were observed and 6/16 (37%) evaluable patients are disease free after a median of 51 mo. Twenty-one patients with relapsed/refractory disease (of whom 13 neuroblastomas) entered the topotecan/cyclophosphamide study: 7/21 (33%) patients responded. Forty-one patients entered the temozolomide study (of whom 16 had neuroblastomas): stable disease and symptom relief were obtained in 15/30 (50%) evaluable patients. Intensive induction with ICE resulted in a faster response with high response rate; a larger study with longer follow-up is needed to confirm a survival advantage. Second-line treatment was effective in obtaining remissions, some of them long lasting. Third-line treatment did not elicit measurable responses in neuroblastoma, but achieved prolonged freedom from disease progression and excellent palliation in several patients.
Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Dacarbazina/análogos & derivados , Dacarbazina/uso terapêutico , Neuroblastoma/tratamento farmacológico , Adolescente , Adulto , Carboplatina/administração & dosagem , Criança , Pré-Escolar , Ciclofosfamida/administração & dosagem , Resistencia a Medicamentos Antineoplásicos , Etoposídeo/administração & dosagem , Feminino , Humanos , Ifosfamida/administração & dosagem , Lactente , Masculino , Recidiva Local de Neoplasia/tratamento farmacológico , Cuidados Paliativos , Temozolomida , Topotecan/administração & dosagem , Resultado do TratamentoRESUMO
In this work we present first results concerning the detailed structure of porous silicon (PS) layers prepared by a new method using a vapour-etching (VE)-based technique. Studies of the photoluminescence properties of VE-based PS show that the visible emission occurs at high energies as compared with PS prepared by conventional techniques. To understand the VE-based PS features, we need to point out the PS microstructure throughout its general morphology. For this purpose a microscopy multiscale study was done. Scanning, conventional transmission, and high-resolution transmission electron microscopes were employed. The investigations were made on PS films prepared from moderately and heavily doped n- and p-type silicon. SEM images show that VE-based PS layers are essentially formed of clusters like interconnected structures. TEM studies show that these clusters are composed of nanocrystallites with different shapes. The effect of the doping type of the starting Si substrate on the characteristics of the PS layers was examined (thickness, porosity, behavior). Pore propagation was found to depend on doping type. The crystallinity of the PS layers was also locally studied in depth.
Assuntos
Cristalização/métodos , Cristalografia/métodos , Membranas Artificiais , Microscopia Eletrônica , Nanotecnologia/métodos , Silício/química , Teste de Materiais , Nanotecnologia/instrumentação , Porosidade , Propriedades de SuperfícieAssuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/administração & dosagem , Doxorrubicina/administração & dosagem , Hepatoblastoma/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Projetos Piloto , Estudos ProspectivosRESUMO
PURPOSE: Evaluation of the possible clinical relevance of DNA ploidy and proliferative activity assessed as S-phase fraction (SPF) in childhood rhabdomyosarcoma (RMS). PATIENTS AND METHODS: We conducted a retrospective study on 59 RMS patients enrolled onto the ICS-RMS88 protocol (seven botryoid, 35 embryonal, and 17 alveolar RMS), for which formalin-fixed paraffin-embedded (FFPE) tissue was available. Nuclear suspensions for cytometric investigation were obtained using a mechanical disaggregation. Tumors were distinguished according to their DNA index (DI) value as follows: diploid (0.9 < DI < 1.1), hyperdiploid (1.1 < or = DI < 1.8 or DI > or = 2.2), and tetraploid (1.8 < or = DI < 2.2); for analysis of SPF, a cutoff value of 14% was used. RESULTS: DNA histograms were diploid in 19 (33%) cases, hyperdiploid in 29 (49%), and tetraploid in 10 (32%). One patient showed both a hyperdiploid and a tetraploid peak. The 5-year overall survival (OS) rate by ploidy status was 73% in hyperdiploid patients as compared with 33% and 25% in diploid and tetraploid patients, respectively (P = .0012). A striking difference emerged when the 5-year OS for the combined diploid and tetraploid RMS groups was compared with survival of the hyperdiploid RMS group: 30% versus 73%, respectively (P = .0006). In addition, the SPF was prognostically relevant: 5-year OS by SPF less than or greater than 14% was 70% and 36%, respectively (P = .009). Multivariate analysis confirmed the importance of DNA content (P = .0006) and SPF (P = .034) in predicting survival. CONCLUSION: These findings confirm that ploidy and SPF are important new prognostic factors that are able to identify selected groups of patients at high risk of treatment failure, even if the tumor's presentation is favorable according to standard criteria.
Assuntos
Ploidias , Rabdomiossarcoma/genética , Adolescente , Divisão Celular , Criança , Pré-Escolar , DNA de Neoplasias/análise , Feminino , Citometria de Fluxo , Formaldeído , Humanos , Lactente , Masculino , Análise Multivariada , Inclusão em Parafina , Estudos Retrospectivos , Rabdomiossarcoma/patologia , Rabdomiossarcoma Alveolar/genética , Rabdomiossarcoma Alveolar/patologia , Rabdomiossarcoma Embrionário/genética , Rabdomiossarcoma Embrionário/patologia , Sensibilidade e EspecificidadeRESUMO
The aim of this paper is to evaluate the role of Doppler and echo color-Doppler in the microsurgical treatment of varicocele. Since December 1993, 87 consecutive patients underwent microsurgical treatment of varicocele. The study demonstrates that Doppler and Color-flow-Duplex scanning provide an accurate, non-invasive method to identify the position of accessory spermatic veins, evaluating at the same time the flow characteristics of the microsurgical anastomosis.
Assuntos
Microcirurgia , Ultrassonografia Doppler em Cores , Varicocele/diagnóstico por imagem , Varicocele/cirurgia , Estudos de Avaliação como Assunto , Humanos , MasculinoRESUMO
The authors present their experience in the study of blood supply of flaps. The machine used to study both pre and postoperatively the myocutaneous flap is the echo-color Doppler, a brand new device which has recently been used in investigating the morphology and the blood supply. The use of such method has provided us with the following information: detailed ultrasound structure of the skin, subcutaneous and muscular tissues of the examined flap; localization of vessels within the flap; size of the vessel in its whole length; quality and speed of both the arterial and venous flow. Such information is very important for the surgeon to plan in detail the reconstruction by knowing the blood supply of myocutaneous flap.
Assuntos
Mama/cirurgia , Retalhos Cirúrgicos/irrigação sanguínea , Ultrassonografia Doppler em Cores , Feminino , Humanos , Mastectomia , Período Pós-OperatórioRESUMO
In neuroblastoma, high levels of mRNA for p140trkA and p75LNGFR neurotrophin receptors are predictive of favorable outcome. Their evaluation by Northern blot, however, requires substantial amounts of tissue and this prevents their routine evaluation as well as the possibility for multicenter studies to be easily carried out. In an attempt to overcome these limitations, the feasibility and reliability of determining both neurotrophin receptors on cryostat sections by immunohistochemistry were assessed, and these findings were compared to those obtained from Northern blot analysis. Primary tumor samples from 28 untreated patients at all stages were evaluated by using H10 anti-p140trkA and ME20.4 anti-p75LNGFR mAbs. Although weak, positive immunostaining was found in 9 of 28 tumors for p140trkA and in 5 of 28 tumors for p75LNGFR. As compared to Northern blot, the concordance rate was 79% (22 of 28 cases) for p140trkA (p < 0.05) and 71% (20 of 28 cases) for p75LNGFR (p < 0.05). No case negative for Northern blot was found to be positive with immunohistochemistry. Since only high mRNA levels for both receptors have been shown to be clinically relevant, their immunohistochemical detection, although less sensitive than Northern blot, can be just as sufficient and reliable as a prognostic tool, and possibly with a better cost-benefit ratio.
Assuntos
Neuroblastoma , Proteínas Proto-Oncogênicas/análise , Receptores Proteína Tirosina Quinases/análise , Receptores de Fator de Crescimento Neural/análise , Anticorpos Monoclonais , Northern Blotting , Criança , Humanos , Imuno-Histoquímica , Neuroblastoma/diagnóstico , Prognóstico , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/imunologia , RNA Mensageiro/análise , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/imunologia , Receptor de Fator de Crescimento Neural , Receptor trkA , Receptores de Fator de Crescimento Neural/genética , Receptores de Fator de Crescimento Neural/imunologia , Células Tumorais Cultivadas/químicaRESUMO
Neuroblastoma, a childhood tumour of the sympathetic nervous system, may in some cases differentiate to a benign ganglioneuroma or regress due to apoptosis. Somatostatin may inhibit neuroblastoma growth and induce apoptosis in vitro and was therefore investigated. Using a radioimmunoassay, we found that all ganglioneuromas contained high somatostatin concentrations (> 16 pmol/g), significantly higher than neuroblastomas (n = 117, median 2.8 pmol/g), healthy adrenals, Wilms' tumours, phaeochromocytomas and other neuroendocrine tumours (P < 0.001). Neuroblastomas contained more somatostatin than control tumours (P < 0.001-0.05). Neuroblastomas amplified for the MYCN oncogene contained less somatostatin than non-amplified tumours (1.2 pmol/g versus 4.0 pmol/g, respectively; P = 0.026). In a clinically unfavourable neuroblastoma subset (age > 12 months, stage 3 or 4) 16 children with high concentrations of somatostatin in primary tumours had a better prognosis than 23 with low somatostatin (46.7% versus 0% survival at 5 years, P < 0.005). Scintigraphy using 111In-pentetreotide identified tumours expressing high-affinity somatostatin receptors in vivo. However, no significant correlation was found between somatostatin receptor expression and peptide content in 15 tumours. Similarly, human SH-SY5Y neuroblastoma xenografts grown in nude rats showed low somatostatin concentrations, but were positive for somatostatin receptor scintigraphy. Treatment of these rats with the somatostatin analogue octreotide seemed to upregulate in vivo receptor expression of somatostatin and vasoactive intestinal peptide more effectively than 13-cis retinoic acid. In conclusion, somatostatin in neuroblastoma is associated with differentiation to benign ganglioneuromas in vivo and favourable outcome in advanced tumours. Furthermore, somatostatin receptor scintigraphy may identify tumours with high-affinity receptors in children that might benefit from targeted therapy using synthetic somatostatin analogues.