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1.
Exp Clin Transplant ; 17(1): 121-123, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-28760117

RESUMO

Organ shortage and increasing donor age in liver transplant are stimulating transplant centers to accept otherwise discarded grafts due to donor age or vascular abnormalities; nevertheless, the use of nonagenarian donor grafts is uncommon because advanced age is associated with a higher risk of ischemic-type biliary lesions and worse long-term graft survival. We herein report the case of a 90-year-old donor with fully replaced right hepatic artery. After back-table vascular assessment, the donor right hepatic artery was anastomosed end-to-end with the gastroduodenal artery with 2 polypropylene 8/0 running sutures. Even if the back-table reconstruction of a replaced right hepatic artery is not associated with an enhanced risk of posttransplant vascular complications, vascular abnormalities might discourage the use of otherwise acceptable elderly grafts. The present case underscores that elderly liver grafts should not be discarded per se even in the presence of vascular variants.


Assuntos
Carcinoma Hepatocelular/cirurgia , Seleção do Doador , Artéria Hepática/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/métodos , Procedimentos de Cirurgia Plástica/métodos , Doadores de Tecidos , Procedimentos Cirúrgicos Vasculares/métodos , Fatores Etários , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Angiografia por Tomografia Computadorizada , Feminino , Artéria Hepática/diagnóstico por imagem , Hepatite B/complicações , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Resultado do Tratamento , Ultrassonografia Doppler
2.
Eur J Radiol ; 96: 65-73, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29103478

RESUMO

Over the past few years, the cross sectional imaging techniques (Computed Tomography - CT and Magnetic Resonance - MR) have improved, allowing a more efficient study of focal and diffuse liver diseases. Many papers had been published about the results of a routinely clinical use of the dual source/dual energy CT techniques and the use of hepatobiliary contrast agents in MR liver studies. As a consequence, these new improvements have diverted the attention away from the Ultrasound technique and its technical and conceptual evolutions. In these years of disinterest, US and especially Contrast Enhanced Ultrasound (CEUS) have consolidated and grown in their application in clinical routine for liver pathologies. In particular, thanks to the introduction of new, dedicated software packages, CEUS has allowed not only qualitative, but also quantitative analysis of lesion microcirculation, thus opening a new era in the evaluation of lesion characterization and response to therapy. Moreover, the renewed interest in liver elastography, a baseline ultrasound-based imaging modality, has led to the development of a competitive technique to assess liver stiffness and then for the evaluation of the progression towards cirrhosis, and characterization of focal liver lesions, opening the way to avoid, in selected cases, liver biopsy. The aim of this review is to offer an up-to-date overview on the state of the art of clinical applications of US and CEUS in the study of focal and diffuse liver pathologies. Besides, it aims to highlight the emerging role of perfusion techniques in the assessment of local and systemic treatment response and to show how the liver evolution from steatosis to fibrosis can be revealed by elastography.


Assuntos
Meios de Contraste , Aumento da Imagem/métodos , Hepatopatias/diagnóstico por imagem , Fígado/diagnóstico por imagem , Ultrassonografia/métodos , Feminino , Humanos , Masculino
3.
Int J Surg ; 44: 26-32, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28624558

RESUMO

BACKGROUND AND OBJECTIVES: Electrochemotherapy is a novel ablation technique combining chemotherapeutic agents with reversible cell membrane electroporation. Previous experiences have shown its efficacy for cutaneous tumors. Its application for deep-seated malignancies is under investigation. We performed a prospective, pilot study to evaluate the feasibility, safety, and efficacy of intraoperative electrochemotherapy for otherwise unresectable colorectal liver metastases. METHODS: Electrochemotherapy with bleomycin was combined with open liver resection and performed with linear or hexagonal needle electrodes according to an individualized pretreatment plan. The primary endpoints were: feasibility, as ratio of completed to planned treatments; safety, and efficacy, as per response assessed at 30 days with MRI and according to RECIST. The secondary endpoint was overall and progression-free survival at month 6. RESULTS: A total of 9 colorectal liver metastases were treated in 5 patients with 20 electrode applications. No intraoperative complications were observed. At day 30, complete response was 55.5% and stable disease 45.5%. All (5) patients reached a 6 months overall survival, and 4 out of 5 patients had 6 months progression free survival. CONCLUSIONS: Electrochemotherapy is a feasible and safe adjunct to open surgery for treatment of unresectable colorectal liver metastases. Larger studies and longer follow-ups are favored to better define its role in the treatment of secondary liver malignancies.


Assuntos
Antineoplásicos/uso terapêutico , Bleomicina/uso terapêutico , Neoplasias Colorretais/patologia , Eletroquimioterapia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Adulto , Idoso , Neoplasias do Colo/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/terapia , Intervalo Livre de Doença , Estudos de Viabilidade , Feminino , Hepatectomia , Humanos , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos
4.
G Ital Med Lav Ergon ; 39(1): 26-33, 2017 Nov.
Artigo em Italiano | MEDLINE | ID: mdl-29916617

RESUMO

OBJECTIVES: Bullying is a manifestation of occupational stress and can therefore be considered as a real "organizational pathology." Include the activities of the surgery dedicated to Mobbing, Unit of Occupational Medicine Sant'Andrea Hospital, which began operations in June 2001. METHODS: In over ten years of operation (July 2012), the sample, consisting of 50.7% for men and 49.3% women, is heterogeneous in age. The schooling of the sample is medium-high as more than 82% have higher education level. The business sector is the service sector accounted for most (84%) than in industry (9%) and agriculture (2%). RESULTS: Of the 1545 patients seen, 1320 completed the diagnostic path, while 225 have stopped. 814 users have been certified for compatibility bullying (63% of cases) with a net reduction of the awards from 2007 onwards. CONCLUSIONS: Considerations are expressed about the possible intervention strategies: the presence of dedicated experts at the counters of listening and professionals as the trusted advisor, to which workers in distress can call on for advice and guidance on how to defend itself from, in accordance with the implemented for years at the Ministry of Health, the establishment of such figures as the manager rehability that in other European countries, are scheduled for some time in work organization.


Assuntos
Bullying/estatística & dados numéricos , Hospitais Universitários/estatística & dados numéricos , Doenças Profissionais/epidemiologia , Saúde Ocupacional , Estresse Psicológico/epidemiologia , Adulto , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/etiologia , Estudos Retrospectivos , Estresse Psicológico/etiologia
5.
Onco Targets Ther ; 9: 6467-6477, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27799794

RESUMO

Lenvatinib is a small oral molecule able to inhibit three of the extracellular and intracellular molecules involved in the modulation of angiogenesis and lymphangiogenesis: vascular endothelial growth factor receptor 1-3, fibroblast growth factor receptor 1-4, and platelet-derived growth factor receptor alpha. Since it is also able to inhibit the REarranged during Transfection oncogene and the protooncogene c-KIT, this drug can also be used to control tumor cell proliferation. The maximum tolerated dose, as demonstrated in Phase I studies, is 25 mg daily. The drug is rapidly absorbed with maximum concentrations achieved within 3 and 5 hours after administration in fasting and nonfasting treated patients, respectively. The most common adverse events, reported in Phase I study and confirmed in the subsequent Phase II and III studies, are hypertension, proteinuria, and gastrointestinal symptoms such as nausea, diarrhea, and stomatitis. In Phase I studies, efficacy of lenvatinib in solid tumors was demonstrated, and these encouraging results have led to the development of a Phase II study using lenvatinib in advance radioiodine-refractory differentiated thyroid cancer (DTCs) patients. Since an overall response rate of 50% was reported, this study also confirmed the efficacy of lenvatinib in DTCs patients with an acceptable toxicity profile. Recently, a Phase III study in patients with DTCs (SELECT study) demonstrated the lenvatinib efficacy in prolonging progression-free survival with respect to the placebo (18.3 vs 3.6 months; P<0.001). Although there was no statistically significant difference in the overall survival of the entire group, this result was observed when the analysis was restricted to both the follicular histotype and the group of senior patients (>65 years). The study confirmed that the most common side effects of this drug are hypertension, diarrhea, decreased appetite, weight loss, nausea, and proteinuria. In this review, we report the results of the main studies on lenvatinib efficacy in patients with advanced and progressive thyroid cancer, mainly in DTCs but also in medullary and anaplastic thyroid cancer. We also compared the efficacy of lenvatinib with that of other tyrosine kinase inhibitors, mainly sorafenib, already tested in the same type of patient population.

6.
Endocr Relat Cancer ; 23(4): R185-205, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27207700

RESUMO

Thyroid cancer is rare, but it is the most frequent endocrine malignancy. Its prognosis is generally favorable, especially in cases of well-differentiated thyroid cancers (DTCs), such as papillary and follicular cancers, which have survival rates of approximately 95% at 40 years. However, 15-20% of cases became radioiodine refractory (RAI-R), and until now, no other treatments have been effective. The same problems are found in cases of poorly differentiated (PDTC) and anaplastic (ATC) thyroid cancers and in at least 30% of medullary thyroid cancer (MTC) cases, which are very aggressive and not sensitive to radioiodine. Tyrosine kinase inhibitors (TKIs) represent a new approach to the treatment of advanced cases of RAI-R DTC, MTC, PDTC, and, possibly, ATC. In the past 10 years, several TKIs have been tested for the treatment of advanced, progressive, and RAI-R thyroid tumors, and some of them have been recently approved for use in clinical practice: sorafenib and lenvatinib for DTC and PDTC and vandetanib and cabozantinib for MTC. The objective of this review is to present the current status of the treatment of advanced thyroid cancer with the use of innovative targeted therapies by describing both the benefits and the limits of their use based on the experiences reported so far. A comprehensive analysis and description of the molecular basis of these therapies, as well as new therapeutic perspectives, are reported. Some practical suggestions are given for both the choice of patients to be treated and their management, with particular regard to the potential side effects.


Assuntos
Neoplasias da Glândula Tireoide/tratamento farmacológico , Animais , Humanos , Terapia de Alvo Molecular , Neoplasias da Glândula Tireoide/genética
8.
J Biomed Nanotechnol ; 11(4): 730-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26310079

RESUMO

Limited tools are available for the non-invasive monitoring of transplanted islets. In this study, we have compared the widely used superparamagnetic iron oxide nanoparticle ferumoxide (Endorem) and multiwalled carbon nanotubes (MWCNTs) for islet cell labeling and tracking. INS-1 E cells and human pancreatic islets isolated from 12 non-diabetic cadaveric organ donors (age: 62 ±16 yr, BMI: 24.6 ± 3.3 kg/m2) were incubated with 50 µg/ml Endorem or 15 µg/ml MWCNTs and studied after 7 or 14 days to assess beta cell morphology, ultrastructure, function, cell survival and in-vitro and in-vivo magnetic resonance imaging (MRI). Light and electron (EM) microscopy showed the well-maintained morphology and ultrastructure of both INS-1 E and human islets during the incubation. EM also revealed the presence of Endorem and MWCNTs within the beta but not the alpha cells. The compounds did not affect beta cell function and viability, and in-vitro MRI showed that labeled INS-1 E cells and human islets could be imaged. Finally, MWCNT labeled human islets were successfully transplanted into the subcutis of rats localized in the desired site via magnetic field and tracked by MRI. These data suggest that MWCNTs can be an alternative labeling compound to be used with human islets for experimental and transplantation studies.


Assuntos
Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/efeitos dos fármacos , Nanotecnologia/métodos , Nanotubos de Carbono/química , Idoso , Animais , Sobrevivência Celular , Células Cultivadas , Meios de Contraste/química , Dextranos/química , Humanos , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/citologia , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita/química , Microscopia Eletrônica , Microscopia de Fluorescência , Pessoa de Meia-Idade , Ratos
9.
J Biol Chem ; 290(4): 2466-76, 2015 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-25505263

RESUMO

Although Sirtuin 3 (SIRT3), a mitochondrially enriched deacetylase and activator of fat oxidation, is down-regulated in response to high fat feeding, the rate of fatty acid oxidation and mitochondrial protein acetylation are invariably enhanced in this dietary milieu. These paradoxical data implicate that additional acetylation modification-dependent levels of regulation may be operational under nutrient excess conditions. Because the heat shock protein (Hsp) Hsp10-Hsp60 chaperone complex mediates folding of the fatty acid oxidation enzyme medium-chain acyl-CoA dehydrogenase, we tested whether acetylation-dependent mitochondrial protein folding contributes to this regulatory discrepancy. We demonstrate that Hsp10 is a functional SIRT3 substrate and that, in response to prolonged fasting, SIRT3 levels modulate mitochondrial protein folding. Acetyl mutagenesis of Hsp10 lysine 56 alters Hsp10-Hsp60 binding, conformation, and protein folding. Consistent with Hsp10-Hsp60 regulation of fatty acid oxidation enzyme integrity, medium-chain acyl-CoA dehydrogenase activity and fat oxidation are elevated by Hsp10 acetylation. These data identify acetyl modification of Hsp10 as a nutrient-sensing regulatory node controlling mitochondrial protein folding and metabolic function.


Assuntos
Chaperonina 10/metabolismo , Jejum , Dobramento de Proteína , Sirtuína 3/metabolismo , Acetilação , Animais , Chaperonina 10/genética , Cromatografia em Gel , Eletroforese em Gel Bidimensional , Ácidos Graxos/metabolismo , Citometria de Fluxo , Regulação da Expressão Gênica , Camundongos , Camundongos Knockout , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Chaperonas Moleculares , Mutagênese , Oxigênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo
10.
EPMA J ; 5(1): 16, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25538797

RESUMO

Predictive, preventive and personalized medicine (PPPM) may have the potential to eventually improve the nature of health care delivery. However, the tools required for a practical and comprehensive form of PPPM that is capable of handling the vast amounts of medical information that is currently available are currently lacking. This article reviews a rationale and method for combining and integrating diagnostic and therapeutic management with information technology (IT), in a manner that supports patients through their continuum of care. It is imperative that any program devised to explore and develop personalized health care delivery must be firmly rooted in clinically confirmed and accepted principles and technologies. Therefore, a use case, relating to hepatocellular carcinoma (HCC), was developed. The approach to the management of medical information we have taken is based on model theory and seeks to implement a form of model-guided therapy (MGT) that can be used as a decision support system in the treatment of patients with HCC. The IT structures to be utilized in MGT include a therapy imaging and model management system (TIMMS) and a digital patient model (DPM). The system that we propose will utilize patient modeling techniques to generate valid DPMs (which factor in age, physiologic condition, disease and co-morbidities, genetics, biomarkers and responses to previous treatments). We may, then, be able to develop a statistically valid methodology, on an individual basis, to predict certain diseases or conditions, to predict certain treatment outcomes, to prevent certain diseases or complications and to develop treatment regimens that are personalized for that particular patient. An IT system for predictive, preventive and personalized medicine (ITS-PM) for HCC is presented to provide a comprehensive system to provide unified access to general medical and patient-specific information for medical researchers and health care providers from different disciplines including hepatologists, gastroenterologists, medical and surgical oncologists, liver transplant teams, interventional radiologists and radiation oncologists. The article concludes with a review providing an outlook and recommendations for the application of MGT to enhance the medical management of HCC through PPPM.

11.
Ig Sanita Pubbl ; 70(2): 211-22, 2014.
Artigo em Italiano | MEDLINE | ID: mdl-25008226

RESUMO

According to Italian Legislative Decree no. 81/2008, workplace safety will have to be introduced in school and university curricula. The main objectives of this study of the Italian Ministry of Labour were to verify knowledge about workplace safety among primary and secondary school students and evaluate the effectiveness of a training course in improving students' knowledge. Three provinces with an above average workforce/injuries ratio (with respect to the national average) were identified. An evaluation questionnaire was administered to students in the three provinces. Students then attended training courses about workplace safety and were then administered the same questionnaire. Primary school students improved by an average of 35.5%, middle school students by 33.3%, high school students by 18.6%. Results suggests that the training intervention was effective.


Assuntos
Currículo , Conhecimentos, Atitudes e Prática em Saúde , Doenças Profissionais/prevenção & controle , Segurança , Local de Trabalho/normas , Adolescente , Criança , Feminino , Humanos , Itália , Masculino , Reprodutibilidade dos Testes , Instituições Acadêmicas , Inquéritos e Questionários
12.
J Hepatocell Carcinoma ; 1: 137-48, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27508183

RESUMO

Diagnosis of hepatocellular carcinoma (HCC) still remains a challenging issue. In the setting of liver cirrhosis, international guidelines have set the noninvasive criteria for HCC diagnosis, represented by the detection of contrast hyperenhancement in the arterial phase (wash-in) and hypoenhancement in the portal or delayed phase (wash-out) with dynamic multi-detector computer tomography or magnetic resonance (MR) imaging. Although highly specific, this typical enhancement pattern has relatively low sensitivity, since approximately one-third of HCC nodules are characterized by atypical enhancement patterns. In atypical HCC nodules larger than 1 cm, the majority of international guidelines recommend liver biopsy. However, there is an increasing interest in exploiting new noninvasive diagnostic tools, to increase the sensitivity of radiological diagnosis of HCC. Diffusion-weighted MR imaging and MR hepatobiliary contrast agents may represent useful tools for the detection and characterization of borderline hypovascular lesions by providing functional information such as water molecule motion in diffusion-weighted imaging and residual hepatobiliary function, which can be impaired early during the course of hepatocarcinogenesis. Also, dual-energy computed tomography (CT) represents an interesting new CT technology that could increase detectability and conspicuity of hypervascular lesions, thus possibly improving CT sensitivity in small HCCs. However, more data and further developments are needed to verify the usefulness of these new technologies in the diagnosis of HCC and to translate these recent advances into clinical practice.

13.
Amino Acids ; 46(3): 511-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23771789

RESUMO

Polyamines, including spermine, spermidine, and the precursor diamine, putrescine, are naturally occurring polycationic alkylamines that are required for eukaryotic cell growth, differentiation, and survival. This absolute requirement for polyamines and the need to maintain intracellular levels within specific ranges require a highly regulated metabolic pathway primed for rapid changes in response to cellular growth signals, environmental changes, and stress. Although the polyamine metabolic pathway is strictly regulated in normal cells, dysregulation of polyamine metabolism is a frequent event in cancer. Recent studies suggest that the polyamine catabolic pathway may be involved in the etiology of some epithelial cancers. The catabolism of spermine to spermidine utilizes either the one-step enzymatic reaction of spermine oxidase (SMO) or the two-step process of spermidine/spermine N (1)-acetyltransferase (SSAT) coupled with the peroxisomal enzyme N (1)-acetylpolyamine oxidase. Both catabolic pathways produce hydrogen peroxide and a reactive aldehyde that are capable of damaging DNA and other critical cellular components. The catabolic pathway also depletes the intracellular concentrations of spermidine and spermine, which are free radical scavengers. Consequently, the polyamine catabolic pathway in general and specifically SMO and SSAT provide exciting new targets for chemoprevention and/or chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinogênese , Neoplasias/tratamento farmacológico , Neoplasias/prevenção & controle , Poliaminas/metabolismo , Aldeídos/metabolismo , Animais , Humanos , Peróxido de Hidrogênio/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia
14.
Dig Liver Dis ; 45(9): 776-81, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23578581

RESUMO

AIMS: This prospective pilot study investigated the feasibility of perfusion computed tomography parameters as surrogate markers of angiogenesis and early response following sorafenib administration in patients with advanced hepatocellular carcinoma. METHODS: Ten patients were evaluated with perfusion computed tomography before starting sorafenib and after 3 months. Blood flow, blood volume, mean transit time, hepatic arterial fraction, and permeability surface-product were compared in tumour lesions and in hepatic parenchyma at baseline and at follow-up. Correlation between these parameters and changes in alpha-fetoprotein levels was calculated. RESULTS: At baseline, blood volume, blood flow, hepatic arterial fraction and permeability surface values were higher in lesions compared to those in hepatic parenchyma, while mean transit time was lower (p<0.05). After sorafenib treatment, only mean transit time was significantly increased versus baseline (p<0.05). At follow-up, plasma alpha-fetoprotein levels decreased in all patients. At follow-up, an inverse correlation was observed between baseline mean transit time and changes in alpha-fetoprotein (r=-0.6685, p=0.0125), as well as a correlation between baseline blood flow and alpha-fetoprotein (r=0.6476, p=0.0167). CONCLUSION: This pilot study suggests that after sorafenib treatment an increase in mean transit time observed in tumour lesions is inversely correlated with alpha-fetoprotein reductions after therapy. Mean transit time may represent a possible marker of response irrespectively of alpha-fetoprotein values.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Fígado/irrigação sanguínea , Neovascularização Patológica/diagnóstico por imagem , alfa-Fetoproteínas/análise , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/tratamento farmacológico , Estudos de Coortes , Estudos de Viabilidade , Feminino , Humanos , Fígado/diagnóstico por imagem , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores/métodos , Neovascularização Patológica/tratamento farmacológico , Niacinamida/análogos & derivados , Niacinamida/uso terapêutico , Imagem de Perfusão/métodos , Compostos de Fenilureia/uso terapêutico , Projetos Piloto , Estudos Prospectivos , Fluxo Sanguíneo Regional , Sorafenibe , Resultado do Tratamento
15.
Abdom Imaging ; 38(2): 290-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23053453

RESUMO

PURPOSE: To analyze Gd-EOB-DTPA-enhanced magnetic resonance (MR) findings of nodules (low-grade dysplastic nodules-LGDNs; high-grade dysplastic nodules-HGDN, and hepatocellular carcinoma-HCC), histologically identified on cirrhotic, explanted livers. METHODS: IRB approval was obtained for this study. Thirty-four patients underwent Gd-EOB-DTPA-enhanced MR examinations (1.5T system), that included 20-min delayed hepatobiliary (HB) phase imaging, before undergoing orthotopic liver transplantation (OLT; mean time MR-OLT: 2.7 months). A total of 102 hepatic nodules were identified and analyzed at histopathological examination, and classified as LGDN, HGDN, and HCC. Two radiologists by consensus performed a quantitative (enhancement ratios, ERs) and a qualitative analyses of signal intensities of identified nodules on vascular dynamic phases (30-35 s after injection-arterial phase; 180-190 s after injection late phase) and on HB phases. Correlation between nodules MR patterns and histological classification was analyzed by means of dedicated statistical software. RESULTS: No differences were appreciable among ERs of HGDN and HCCs on HB phase (P > 0.001). Lesions' enhancement on vascular dynamic and on HB phases significantly correlated to histological classification of nodules (P < 0.0001). Nodular hyperintensity on arterial phase and hypointensity on late phase were highly predictive for HCC (PPV 100%), with a moderate sensitivity (72.5%). Nodular hypointensity on HB phase was detected on 39/40 HCCs (sensitivity 97.5%) and in 21/30 HGDNs, whereas no LGDN showed it. CONCLUSIONS: Hyperenhancement on arterial phase and hypointensity on late phase are the most specific clues for the diagnosis of HCC. Hypointensity on HB phase shows a PPV of 100% in suggesting nodular premalignancy/malignancy, independently from nodular dynamic vascular enhancement.


Assuntos
Carcinoma Hepatocelular/patologia , Aumento da Imagem , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Meios de Contraste , Feminino , Humanos , Cirrose Hepática/cirurgia , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas , Radiologia Intervencionista
16.
Acta Biomater ; 9(4): 6105-15, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23261922

RESUMO

The features of implant devices and the reactions of bone-derived cells to foreign surfaces determine implant success during osseointegration. In an attempt to better understand the mechanisms underlying osteoblasts attachment and spreading, in this study adhesive peptides containing the fibronectin sequence motif for integrin binding (Arg-Gly-Asp, RGD) or mapping the human vitronectin protein (HVP) were grafted on glass and titanium surfaces with or without chemically induced controlled immobilization. As shown by total internal reflection fluorescence microscopy, human osteoblasts develop adhesion patches only on specifically immobilized peptides. Indeed, cells quickly develop focal adhesions on RGD-grafted surfaces, while HVP peptide promotes filopodia, structures involved in cellular spreading. As indicated by immunocytochemistry and quantitative polymerase chain reaction, focal adhesions kinase activation is delayed on HVP peptides with respect to RGD while an osteogenic phenotypic response appears within 24h on osteoblasts cultured on both peptides. Cellular pathways underlying osteoblasts attachment are, however, different. As demonstrated by adhesion blocking assays, integrins are mainly involved in osteoblast adhesion to RGD peptide, while HVP selects osteoblasts for attachment through proteoglycan-mediated interactions. Thus an interfacial layer of an endosseous device grafted with specifically immobilized HVP peptide not only selects the attachment and supports differentiation of osteoblasts but also promotes cellular migration.


Assuntos
Materiais Revestidos Biocompatíveis/metabolismo , Adesões Focais/fisiologia , Oligopeptídeos/metabolismo , Osteoblastos/fisiologia , Vitronectina/metabolismo , Adsorção , Adesão Celular , Movimento Celular , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Humanos , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/química , Osteoblastos/citologia , Vitronectina/química
19.
Amino Acids ; 42(2-3): 769-74, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21901471

RESUMO

During our study of the cytostatic effect of agmatine, we were able to isolate an agmatine resistant clone from a parental hepatoma cell line, HTC. These cells, called Agres, had slower growth rate than the parental cells when cultured in normal medium. The modification in polyamine content induced by agmatine was much lower in these cells and ornithine decarboxylase, S-adenosylmethionine decarboxylase and spermidine/spermine acetyltransferase activities were much less affected. By investigating the mechanism responsible for these modifications, it was shown that agmatine and polyamines were not taken up by Agres cells. Their resistance to the antiproliferative effects of agmatine may thus arise from a lack of the polyamine transport system. Moreover, Agres cells were able to take up both glutamic acid and arginine at a rate significantly higher than that detected for HTC cells, most likely to provide components for compensatory increase of PA synthesis. These results emphasize the importance of polyamine transport for cell growth.


Assuntos
Agmatina/farmacologia , Neoplasias Hepáticas Experimentais/patologia , Animais , Western Blotting , Linhagem Celular Tumoral , Imunofluorescência , Ratos
20.
Amino Acids ; 42(2-3): 761-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21800257

RESUMO

Agmatine, a divalent diamine with two positive charges at physiological pH, is transported into the matrix of liver mitochondria by an energy-dependent mechanism, the driving force of which is the electrical membrane potential. Its binding to mitochondrial membranes is studied by applying a thermodynamic treatment of ligand-receptor interactions on the analyses of Scatchard and Hill. The presence of two mono-coordinated binding sites S(1) and S(2), with a negative influence of S(2) on S(1), has been demonstrated. The calculated binding energy is characteristic for weak interactions. S(1) exhibits a lower binding capacity and higher binding affinity both of about two orders of magnitude than S(2). Experiments with idazoxan, a ligand of the mitochondrial imidazoline receptor I(2), demonstrate that S(1) site is localized on this receptor while S(2) is localized on the transport system. S(1) would act as a sensor of exogenous agmatine concentration, thus modulating the transport of the amine by its binding to S(2).


Assuntos
Agmatina/metabolismo , Receptores de Imidazolinas/metabolismo , Mitocôndrias/metabolismo , Animais , Sítios de Ligação , Termodinâmica
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