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1.
Eur J Nucl Med Mol Imaging ; 51(2): 590-603, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37747578

RESUMO

AIMS: To report long-term outcomes of relapsed prostate cancer (PC) patients treated in a prospective single-arm study with extended-nodal radiotherapy (ENRT) and [11C]-choline positron emission tomography (PET)/computed tomography (CT)-guided simultaneous integrated boost (SIB) to positive lymph nodes (LNs). METHODS: From 12/2009 to 04/2015, 60 PC patients with biochemical relapse and positive LNs only were treated in this study. ENRT at a median total dose (TD) = 51.8 Gy/28 fr and PET/CT-guided SIB to positive LNs at a median TD = 65.5 Gy was prescribed. Median PSA at relapse was 2.3 (interquartile range, IQR:1.3-4.0) ng/ml. Median number of positive LNs: 2 (range: 1-18). Androgen deprivation therapy (ADT) was prescribed for 48 patients for a median of 30.7 (IQR: 18.5-43.1) months. RESULTS: Median follow-up from the end of salvage treatment was 121.8 (IQR: 116.1, 130.9) months; 3-, 5-, and 10-year BRFS were 45.0%, 36.0%, and 24.0%, respectively; DMFS: 67.9%, 57.2%, and 45.2%; CRFS: 62.9%, 53.9%, and 42.0%; and OS: 88.2%, 76.3%, and 47.9%, respectively. Castration resistance (p < 0.0001) and ≥ 6 positive LN (p = 0.0024) significantly influenced OS at multivariate analysis. Castration resistance (p < 0.0001 for both) influenced DMFS and CRFS in multivariate analysis. CONCLUSIONS: In PC relapsed patients treated with ENRT and [11C]-choline-PET/CT-guided SIB for positive LNs, with 10-year follow-up, a median Kaplan-Meier estimate CRFS of 67 months and OS of 110 months were obtained. These highly favorable results should be confirmed in a prospective, randomized trial.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Humanos , Masculino , Antagonistas de Androgênios/uso terapêutico , Radioisótopos de Carbono , Colina , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/radioterapia , Recidiva Local de Neoplasia/tratamento farmacológico , Tomografia por Emissão de Pósitrons , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/patologia , Ensaios Clínicos como Assunto
2.
Phys Rev Lett ; 131(3): 031802, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37540851

RESUMO

We report the direct observation of muon neutrino interactions with the SND@LHC detector at the Large Hadron Collider. A dataset of proton-proton collisions at sqrt[s]=13.6 TeV collected by SND@LHC in 2022 is used, corresponding to an integrated luminosity of 36.8 fb^{-1}. The search is based on information from the active electronic components of the SND@LHC detector, which covers the pseudorapidity region of 7.2<η<8.4, inaccessible to the other experiments at the collider. Muon neutrino candidates are identified through their charged-current interaction topology, with a track propagating through the entire length of the muon detector. After selection cuts, 8 ν_{µ} interaction candidate events remain with an estimated background of 0.086 events, yielding a significance of about 7 standard deviations for the observed ν_{µ} signal.

3.
Sci Data ; 8(1): 218, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385471

RESUMO

The OPERA experiment was designed to discover the vτ appearance in a vµ beam, due to neutrino oscillations. The detector, located in the underground Gran Sasso Laboratory, consisted of a nuclear photographic emulsion/lead target with a mass of about 1.25 kt, complemented by electronic detectors. It was exposed from 2008 to 2012 to the CNGS beam: an almost pure vµ beam with a baseline of 730 km, collecting a total of 1.8·1020 protons on target. The OPERA Collaboration eventually assessed the discovery of vµâ†’vτ oscillations with a statistical significance of 6.1 σ by observing ten vτ CC interaction candidates. These events have been published on the Open Data Portal at CERN. This paper provides a detailed description of the vτ data sample to make it usable by the whole community.

4.
Eur Rev Med Pharmacol Sci ; 25(4): 2099-2108, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33660823

RESUMO

OBJECTIVE: Ustekinumab (UST) is an anti-IL12/23 antibody for the treatment of Crohn's Disease (CD). The aim of this study was to compare the efficacy and safety of UST in a large population-based cohort of CD patients who failed previous treatment with other biologics. PATIENTS AND METHODS: 194 CD patients (108 males and 86 females, mean age 48 years (range 38-58 years) were retrospectively reviewed. 147 patients were already treated with anti-TNFα (75.8%), and 47 (24.2%) patients were already treated with anti-TNFα and vedolizumab. Concomitant treatment with steroids was present in 177 (91.2%) patients. RESULTS: At week 12, clinical remission was achieved in 146 (75.2%) patients. After a mean follow-up of 6 months, clinical remission was maintained in 135 (69.6%) patients; at that time, mucosal healing was assessed in 62 (31.9%) patients, and it was achieved in 33 (53.2) patients. Three (1.5%) patients were submitted to surgery. Steroid-free remission was achieved in 115 (59.3%) patients. Both serum C-Reactive Protein and Fecal Calprotectin (FC) levels were significantly reduced with respect to baseline levels during follow-up. A logistic regression, UST therapy as third-line therapy (after both anti-TNFα and vedolizumab), FC >200 µg/g, and HBI ≥8 were significantly associated with lack of remission. Adverse events occurred in 5 (2.6%) patients, and four of them required suspension of treatment. CONCLUSIONS: UST seemed to be really effective and safe in CD patients unresponsive to other biologic treatments, especially when used as second-line treatment.


Assuntos
Doença de Crohn/tratamento farmacológico , Ustekinumab/uso terapêutico , Adulto , Estudos de Coortes , Feminino , Humanos , Itália , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Ustekinumab/administração & dosagem , Ustekinumab/efeitos adversos
5.
Sci Rep ; 9(1): 16892, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729431

RESUMO

α-Crystallin B (CRYAB or HspB5) is a chaperone member of the small heat-shock protein family that prevents aggregation of many cytosolic client proteins by means of its ATP-independent holdase activity. Surprisingly, several reports show that CRYAB exerts a protective role also extracellularly, and it has been recently demonstrated that CRYAB is secreted from human retinal pigment epithelial cells by an unconventional secretion pathway that involves multi-vesicular bodies. Here we show that autophagy is crucial for this unconventional secretion pathway and that phosphorylation at serine 59 residue regulates CRYAB secretion by inhibiting its recruitment to the autophagosomes. In addition, we found that autophagosomes containing CRYAB are not able to fuse with lysosomes. Therefore, CRYAB is capable to highjack and divert autophagosomes toward the exocytic pathway, inhibiting their canonical route leading to the lysosomal compartment. Potential implications of these findings in the context of disease-associated mutant proteins turn-over are discussed.


Assuntos
Autofagossomos/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Via Secretória/fisiologia , Cadeia B de alfa-Cristalina/metabolismo , Animais , Autofagia/fisiologia , Células COS , Chlorocebus aethiops , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lisossomos/metabolismo , Proteínas Mutantes/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Serina/metabolismo , Cadeia B de alfa-Cristalina/química , Cadeia B de alfa-Cristalina/genética
6.
Data Brief ; 21: 269-275, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30364666

RESUMO

This manuscript presents data related to the research article entitled "Synthesis and characterization of sustainable polyurethane foams based on polyhydroxyls with different terminal groups" (DOI: 10.1016/j.polymer.2018.06.077) [1]. We provide Supplementary data on the chemical properties, in terms of FTIR characterization, of polyhydroxyls produced starting from bio-based feedstock (biosuccinic acid and 1,4 butandiol) and thermal properties (glass transition temperature-Tg and thermal degradation behavior) of polyurethane and copolymer urethane-amide foams manufactured from the aforementioned polyhydroxyls. The FTIR characterization elucidates the chemical structure of polyhydroxyls and allows to make some hypothesis on their reaction routes with the isocyanate molecules. The thermal characterization revealed that the addition of bio-based polyhydroxyls to the sample formulations improves both the glass transition and degradation temperature of the foams. These foamed products exhibit potential performances to be applied as a substitute for conventional polyurethane foams.

7.
Phys Rev Lett ; 120(21): 211801, 2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-29883136

RESUMO

The OPERA experiment was designed to study ν_{µ}→ν_{τ} oscillations in the appearance mode in the CERN to Gran Sasso Neutrino beam (CNGS). In this Letter, we report the final analysis of the full data sample collected between 2008 and 2012, corresponding to 17.97×10^{19} protons on target. Selection criteria looser than in previous analyses have produced ten ν_{τ} candidate events, thus reducing the statistical uncertainty in the measurement of the oscillation parameters and of ν_{τ} properties. A multivariate approach for event identification has been applied to the candidate events and the discovery of ν_{τ} appearance is confirmed with an improved significance level of 6.1σ. |Δm_{32}^{2}| has been measured, in appearance mode, with an accuracy of 20%. The measurement of the ν_{τ} charged-current cross section, for the first time with a negligible contamination from ν[over ¯]_{τ}, and the first direct evidence for the ν_{τ} lepton number are also reported.

9.
Phys Rev Lett ; 115(12): 121802, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26430986

RESUMO

The OPERA experiment was designed to search for ν_{µ}→ν_{τ} oscillations in appearance mode, i.e., by detecting the τ leptons produced in charged current ν_{τ} interactions. The experiment took data from 2008 to 2012 in the CERN Neutrinos to Gran Sasso beam. The observation of the ν_{µ}→ν_{τ} appearance, achieved with four candidate events in a subsample of the data, was previously reported. In this Letter, a fifth ν_{τ} candidate event, found in an enlarged data sample, is described. Together with a further reduction of the expected background, the candidate events detected so far allow us to assess the discovery of ν_{µ}→ν_{τ} oscillations in appearance mode with a significance larger than 5σ.

10.
J Endocrinol Invest ; 35(4): 365-71, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21597316

RESUMO

Thiazolidinediones (TZD), a class of anti-diabetic drugs, determine bone loss and increase fractures particularly in post-menopausal women, thus suggesting a protective role of sex steroids. We have previously demonstrated that the TZD rosiglitazone (RGZ) negatively affects bone mass by inhibiting osteoblastogenesis, yet inducing adipogenesis, in bone marrow-derived human mesenchymal stem cells (hMSC). The aim of this study was to determine whether estrogens and androgens are able to revert the effects of RGZ on bone. hMSC express estrogen receptor α and ß and the androgen receptor. We found that 17ß-estradiol (10 nM), the phytoestrogen genistein (10 nM), testosterone (10 nM) and the non-aromatizable androgens dihydrotestosterone (10 nM) and methyltrienolone (10 nM) effectively counteracted the adipogenic effect of RGZ (1 µM) in hMSC induced to differentiate into adipocytes, as determined by evaluating the expression of the adipogenic marker peroxisome proliferator-activated receptor γ and the percentage of fat cells. Furthermore, when hMSC were induced to differentiate into osteoblasts, all the above-mentioned molecules and also quercetin, another phytoestrogen, significantly reverted the inhibitory effect of RGZ on the expression of the osteogenic marker osteocalcin and decreased the number of fat cells observed after RGZ exposure. Our study represents, to our knowledge, the first demonstration in hMSC that androgens, independently of their aromatization, and estrogens are able to counteract the negative effects of RGZ on bone. Our data, yet preliminary, suggest the possibility to try to prevent the negative effects of TZD on bone, using steroid receptor modulators, such as plant-derived phytoestrogens, which lack evident adverse effects.


Assuntos
Adipogenia/efeitos dos fármacos , Androgênios/farmacologia , Estrogênios/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Tiazolidinedionas/antagonistas & inibidores , Tiazolidinedionas/farmacologia , Adipócitos/efeitos dos fármacos , Adipócitos/fisiologia , Adipogenia/fisiologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Humanos , Masculino , Células-Tronco Mesenquimais/fisiologia , Rosiglitazona
11.
Phys Rev Lett ; 104(17): 174801, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20482112

RESUMO

The electron-positron collider DAPhiNE, the Italian Phi factory, has been recently upgraded in order to implement an innovative collision scheme based on large crossing angle, small beam sizes at the crossing point, and compensation of beam-beam interaction by means of sextupole pairs creating a "crab-waist" configuration in the interaction region. Experimental tests of the novel scheme exhibited an increase by a factor of 3 in the peak luminosity of the collider with respect to the performances reached before the upgrade. In this Letter we present the new collision scheme, discuss its advantages, describe the hardware modifications realized for the upgrade, and report the results of the experimental tests carried out during commissioning of the machine in the new configuration and standard operation for the users.

12.
Br J Cancer ; 102(4): 685-92, 2010 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-20068562

RESUMO

BACKGROUND: Neuroblastoma (NB) is the most common extra-cranial solid tumour in infants. Unfortunately, most children present with advanced disease and have a poor prognosis. There is in vitro evidence that the peroxisome proliferator-activated receptor gamma (PPARgamma) might be a target for pharmacological intervention in NB. We have previously demonstrated that the PPARgamma agonist rosiglitazone (RGZ) exerts strong anti-tumoural effects in the human NB cell line, SK-N-AS. The aim of this study was to evaluate whether RGZ maintains its anti-tumoural effects against SK-N-AS NB cells in vivo. METHODS AND RESULTS: For this purpose, tumour cells were subcutaneously implanted in nude mice, and RGZ (150 mg kg(-1)) was administered by gavage daily for 4 weeks. At the end of treatment, a significant tumour weight inhibition (70%) was observed in RGZ-treated mice compared with control mice. The inhibition of tumour growth was supported by a strong anti-angiogenic activity, as assessed by CD-31 immunostaining in tumour samples. The number of apoptotic cells, as determined by cleaved caspase-3 immunostaining, seemed lower in RGZ-treated animals at the end of the treatment period than in control mice, likely because of the large tumour size observed in the latter group. CONCLUSIONS: To our knowledge, this is the first demonstration that RGZ effectively inhibits tumour growth in a human NB xenograft and our results suggest that PPARgamma agonists may have a role in anti-tumoural strategies against NB.


Assuntos
Neuroblastoma/patologia , Tiazolidinedionas/farmacologia , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Nus , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , PPAR gama/agonistas , PPAR gama/genética , PPAR gama/metabolismo , Rosiglitazona , Tiazolidinedionas/uso terapêutico , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
13.
J Endocrinol Invest ; 33(7): 455-60, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19955849

RESUMO

BACKGROUND AND AIM: Radiotherapy may be used as an adjuvant treatment of pituitary adenomas. The aim of our study was to present our experience of multimodal treatment of pituitary adenomas, consisting in temporary implantation of (192)Ir-labeled wires following transphenoidal surgery. SUBJECTS AND METHODS: An observational investigation was performed on a series of 80 patients undergoing surgery (S) for pituitary adenomas between 1982 and 2000, some of whom received post-operative external beam radiotherapy (EBRT) (no.=19 between 1982 and 1990), brachytherapy (B) (no.=35, all after 1991), or both irradiation modalities (EBRT+B) (no.=14). The different treatments were compared in terms of hormonal normalization in the subgroup of patients with hypersecreting adenomas, tumor control, and side effects. RESULTS: Hormonal normalization was obtained in 84% of S+B patients and in 61% of S+EBRT patients. Tumor control was obtained in 74.3% of S+B patients and in 63.1% of S+EBRT patients. Anterior pituitary hormones deficits ranged from 8.6-34% in S+B patients and from 15.8-47.4% in S+EBRT patients, after a mean follow-up of 14 yr. The latter group also showed a higher rate of multiple deficits (42.1% vs 22.8%). Diabetes insipidus and other major complications were rare events in all groups. CONCLUSIONS: We presented one original experience regarding brachytherapy in the management of pituitary tumors, which turned out to be effective and safe. Additional prospective, and possibly randomized, studies should clarify whether in the era of 3-dimensional conformal radiotherapy and stereotactic radiotherapy this treatment modality may still have a role.


Assuntos
Adenoma/radioterapia , Braquiterapia/métodos , Radioisótopos de Irídio/uso terapêutico , Neoplasias Hipofisárias/radioterapia , Adenoma/cirurgia , Adulto , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hormônios Hipofisários/metabolismo , Neoplasias Hipofisárias/cirurgia , Estudos Retrospectivos
14.
Int J Cosmet Sci ; 31(4): 271-7, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19496838

RESUMO

Sensitive skin is a dermatological problem of increasing incidence in western countries and is sometimes associated with atopic condition and bacterial sovrainfection. The purpose of this study is to evaluate in a double blind, randomized, placebo controlled trial the efficacy of gluco-oligosaccharide and collagen tripeptide F in controlling the signs and symptoms of sensitive atopic skin. Forty female subjects (age, 30-59 years) affected by non-lesional atopic sensitive skin entered the study. Skin sensitivity was determined by a dermatologist on the basis of medical history, stinging test, dermatological examination and a questionnaire. A treatment with the test products (active and placebo) was carried out for 4 weeks. Measurements and clinical evaluation were carried out at baseline and at the end of the study. The following objective parameters investigated were bacterial count, skin pH and colour, transepidermal water loss (TEWL), stratum corneum hydration, skin roughness and mechanical properties. Clinical assessment included also a scoring system for dryness, desquamation, irritation, erythema and papules. Significant differences were found in the active treated group when compared with the placebo and in particular for instrumental parameters of roughness (P < 0.02), volume (P < 0.01), TEWL (P < 0.02), erythema (P < 0.0006) and clinical parameters of dryness, desquamation and irritation (P < 0.001). Moisturization levels and skin colour improved significantly in both the active and placebo groups. In conclusion, the study shows that the modulation of bacterial proliferation and normalization of skin barrier properties and stratum corneum moisturization can improve the symptoms of sensitive skin.


Assuntos
Colágeno Tipo I/administração & dosagem , Dermatite Atópica/tratamento farmacológico , Oligossacarídeos/administração & dosagem , Fragmentos de Peptídeos/administração & dosagem , Administração Tópica , Adulto , Contagem de Colônia Microbiana , Dermatite Atópica/microbiologia , Dermatite Atópica/patologia , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Staphylococcus aureus/crescimento & desenvolvimento , Propriedades de Superfície/efeitos dos fármacos , Perda Insensível de Água/efeitos dos fármacos
15.
Phys Rev Lett ; 102(11): 114502, 2009 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-19392204

RESUMO

We discuss two independent, large scale experiments performed in two wave basins of different dimensions in which the statistics of the surface wave elevation are addressed. Both facilities are equipped with a wave maker capable of generating waves with prescribed frequency and directional properties. The experimental results show that the probability of the formation of large amplitude waves strongly depends on the directional properties of the waves. Sea states characterized by long-crested and steep waves are more likely to be populated by freak waves with respect to those characterized by a large directional spreading.

16.
Exp Cell Res ; 315(2): 264-73, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19014933

RESUMO

Current immunosuppressive protocols have reduced rejection occurrence in heart transplantation; nevertheless, management of heart transplant recipients is accompanied by major adverse effects, due to drug doses close to toxic range. In allograft rejection, characterized by T-helper 1 (Th1) cell-mediated response, the CXCL10-CXCR3 axis plays a pivotal role in triggering a self-promoting inflammatory loop. Indeed, CXCL10 intragraft production, required for initiation and development of graft failure, supports organ infiltration by Th1 cells. Thus, targeting the CXCL10-CXCR3 axis while avoiding generalized immunosuppression, may be of therapeutic significance. Based on preclinical evidence for immunoregulatory properties of vitamin D receptor agonists, we propose that a less hypercalcemic vitamin D analogue, BXL-01-0029, might have the potential to contribute to rejection management. We investigated the effect of BXL-01-0029 on CXCL10 secretion induced by proinflammatory stimuli, both in human isolated cardiomyocytes (Hfcm) and purified CD4+ T cells. Mycophenolic acid (MPA), the active agent of mycophenolate mofetil, was used for comparison. BXL-01-0029 inhibited IFNgamma and TNFalpha-induced CXCL10 secretion by Hfcm more potently than MPA, impairing cytokine synergy and pathways. BXL-01-0029 reduced also CXCL10 protein secretion and gene expression by CD4+ T cells. Furthermore, BXL-01-0029 did not exert any toxic effect onto both cell types, suggesting its possible use as a dose-reducing agent for conventional immunosuppressive drugs in clinical transplantation.


Assuntos
Colecalciferol/farmacologia , Imunossupressores/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Western Blotting , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quimiocina CXCL10/genética , Quimiocina CXCL10/metabolismo , Colecalciferol/análogos & derivados , Expressão Gênica/efeitos dos fármacos , Humanos , Interferon gama/metabolismo , Interferon gama/farmacologia , Ionomicina/farmacologia , Microscopia de Fluorescência , Ácido Micofenólico/farmacologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Receptores de Calcitriol/agonistas , Receptores de Interferon/genética , Receptores de Interferon/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT1/metabolismo , Linfócitos T/citologia , Linfócitos T/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Receptor de Interferon gama
17.
J Endocrinol Invest ; 31(9): 809-19, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18997494

RESUMO

Chemokines exert their multifunctional role in several physiologic and pathologic processes through interaction with their specific receptors. Much evidence have revealed that metastatic spread tumor cells may use chemokine-mediated mechanisms. In particular, an involvement of stromal cell-derived factor-1 (SDF-1) in growth of primary tumors and in metastatic process has been demonstrated. Indeed, it has been suggested that CXCR4 expression by tumor cells, plays a critical role in cell metastasis by a chemotactic gradient to organs expressing the ligand SDF-1. Moreover, CXCR4 overexpression correlated with poor prognosis in many types of cancer. In physiologic condition, SDF-1 also plays an essential role modulating stem cell proliferation, survival, and homing through its canonical receptor CXCR4. Recently, several studies have demonstrated the existence of a small subset of cancer cells which share many characteristics with stem cells and named cancer stem cells (CSC). They constitute a reservoir of self-sustaining cells with the ability to maintain the tumor growth. In particular, most of them express CXCR4 receptor and respond to a chemotactic gradient of its specific ligand SDF-1, suggesting that CSC probably represent a subpopulation capable of initiating metastasis. This review focuses on the role of SDF-1/CXCR4 axis in cancer and in the metastatic progression by tumoral cells, as well as the role of CSC in tumor pathogenesis and in metastatic process. A better understanding of migratory mechanism involving cancer cells and CSC provides a powerful tool for developing novel therapies reducing both local and distant recurrences.


Assuntos
Quimiocina CXCL12/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Receptores CXCR4/metabolismo , Humanos , Metástase Neoplásica
18.
J Endocrinol ; 198(3): 523-32, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18612048

RESUMO

The exposure of neurons to high glucose concentrations is considered a determinant of diabetic neuropathy, whereas members of the IGF system are neurotropic factors. Here, we investigated the effects of constant and intermittent high glucose concentrations on IGF1 and IGF-binding proteins (IGFBPs) in human neuroblast long-term cell cultures fetal neuroepithelial cells (FNC). These cells express the IGF1 receptor, and express and release in the culture medium IGFBP2, IGFBP4, and IGF1. The release of IGF1 was significantly increased by 17beta-estradiol (10 nM). IGF1 (100 nM) treatment determined a significant increase of IGFBP2 and a decrease of IGFBP4 release. In addition, IGF1 (1-100 nM) stimulated FNC cell proliferation in a dose-dependent manner. We hypothesized that this effect may be, at least partially, due to IGF1-induced up-regulation of the expression of the Alzheimer's disease related gene SELADIN-1 (now known as DHCR24 ), which acts as a pro-survival factor for neuronal cells. Conversely, the exposure to intermittent (20/10 mM), but not stable (20 mM), high glucose concentrations decreased the release of IGF1 and IGFBP2 in the culture medium and inhibited FNC growth by inducing apoptosis. The latter was prevented by the addition of IGF1 to the culture medium. Furthermore, high glucose concentrations reduced the expression of DHCR24. In conclusion, our results indicate for the first time that intermittent high glucose concentrations, similar to those observed in poorly controlled diabetic patients, may contribute to the development of diabetic neuropathy by interfering with the tropic effects exerted by the IGF system, and suggest the involvement of the neuroprotective factor DHCR24.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Glucose/farmacologia , Proteínas do Tecido Nervoso/fisiologia , Células Neuroepiteliais/efeitos dos fármacos , Células Neuroepiteliais/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/fisiologia , Receptor IGF Tipo 1/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Humanos , Immunoblotting , Marcação In Situ das Extremidades Cortadas , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/farmacologia , Proteína 4 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 4 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 4 de Ligação a Fator de Crescimento Semelhante à Insulina/farmacologia , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Proteínas do Tecido Nervoso/genética , Células Neuroepiteliais/citologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Receptor IGF Tipo 1/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos
19.
J Endocrinol ; 197(2): 437-46, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18434374

RESUMO

Thyroid hormones (TH) play an important role in the development of human brain, by regulating the expression of specific genes. Selective Alzheimer's disease indicator-1 (seladin-1) is a recently discovered gene with neuroprotective properties, which has been found to be down-regulated in brain regions affected by Alzheimer's disease. Seladin-1 has anti-apoptotic properties mainly due to the inhibition of the activation of caspase 3. The aim of this study was to determine whether seladin-1 may be regarded as a new mediator of the effects of TH in the developing brain. In order to demonstrate this hypothesis, the effects of TH both on cell differentiation and on the expression of seladin-1 were assessed in two different cell models, i.e. fetal human neuroepithelial cells (FNC) and human mesenchymal stem cells (hMSC), which can be differentiated into neurons. 3,3',5-Triiodothyronine (T3) determined different biological responses (inhibition of cell adhesion, induction of migration, and increase in the expression of the neuronal marker neurofilament-M and Na+ and Ca2+ channel functionality) in both FNC and hMSC, which express TH receptors. Then, we showed that TH significantly increase the expression levels of seladin-1, and that T3 effectively prevents camptothecin-induced apoptosis. However, in hMSC-derived neurons the expression of seladin-1 was not affected by TH. Our results demonstrated for the first time that seladin-1 is a novel TH-regulated gene in neuronal precursors. In view of its anti-apoptotic activity, it might be hypothesized that one of the functions of the increased seladin-1 levels in the developing brain may be to protect neuronal precursor cells from death.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas do Tecido Nervoso/genética , Neurônios/efeitos dos fármacos , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Células-Tronco/efeitos dos fármacos , Tri-Iodotironina/farmacologia , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Canais de Cálcio Tipo L/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Neurônios/metabolismo , RNA Mensageiro/análise , Receptores dos Hormônios Tireóideos/genética , Sódio/metabolismo , Células-Tronco/metabolismo
20.
Eur J Gynaecol Oncol ; 29(1): 101-4, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18386478

RESUMO

BACKGROUND: Neuroendocrine tumours are a heterogeneous group of separate clinico-pathological entities which have a common characteristic, i.e., expression of potential endocrine differentiation. In the ovary, the term "neuroendocrine" relates mainly to widely known carcinoids, but it may also be applied to rare neuroendocrine carcinomas as non-small cell type and small cell carcinomas of pulmonary type. In the literature only 11 cases of primary ovarian non-small cell neurendocrine carcinomas have been described and ten of these were associated with a surface epithelial ovarian tumour. Small cell neuroendocrine carcinoma of the ovary is a rare malignant tumour of the ovary. Advanced small cell carcinoma of the ovary is a very aggressive tumour with an overall poor prognosis and unfavourable outcome. CASE REPORT: The case reported is unique in the literature because the authors describe a rare case of endometrial metastasis of a primary ovarian non-small cell neurendocrine carcinoma without any surface epithelial ovarian tumour association. The tumour invaded up to less than half of the myometrium. The first symptoms were related to endometrial metastasis as metrorrhagia and pelvic pain while the asymptomatic presence of primary ovarian carcinoma was not acknowledged with physical examination, routine biochemistry, tumour markers, blood count and traditional transvaginal greyscale ultrasound. CONCLUSION: Magnetic resonance and three-dimensional (3D) ultrasonography with power Doppler are a great help in the diagnosis of ovarian localisation but only immunohistochemistry on histological material can provide a correct diagnosis. Immunohistochemistry expression of Ki67 is a useful marker of malignancy. Due to the rarity of this neoplasm, a general consensus for optimal treatment has yet to emerge. The reported biological aggressiveness of these tumours prompts combined treatment with radical surgery and adjuvant polychemotherapy.


Assuntos
Carcinoma Neuroendócrino/secundário , Neoplasias do Endométrio/secundário , Neoplasias Ovarianas/patologia , Carcinoma Neuroendócrino/complicações , Carcinoma Neuroendócrino/diagnóstico por imagem , Neoplasias do Endométrio/complicações , Neoplasias do Endométrio/diagnóstico por imagem , Feminino , Humanos , Metrorragia/etiologia , Pessoa de Meia-Idade , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/diagnóstico por imagem , Dor Pélvica/etiologia , Ultrassonografia
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