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1.
Int J Colorectal Dis ; 34(11): 1849-1856, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31520198

RESUMO

AIM: Several studies demonstrated the prognostic value of the neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and platelet-to-white blood cells ratio (PWR) in different types of tumors. However, there is no information about a possible role of NLR, PLR and PWR as predictor of presence of metastasis or multifocal disease in patients undergoing surgery with curative intent for midgut NET. The aim of our study was to test the role of preoperative NLR, PLR and PWR as predictors of patients undergoing surgery with curative intent for midgut NET. METHODS: We retrospectively enrolled seven foregut, 35 midgut and six hindgut NET patients with gastrointestinal neuroendocrine tumors operated in our Units from January 2005 to June 2016. Details about preoperative laboratory data, surgical operation, histology and follow-up were retrieved. Non-parametric statistics, ROC curve analysis and survival analysis were used. RESULTS: NLR was significantly higher in patients with distant metastasis (p = 0.04). The ROC curve analysis indicated that a threshold value of NLR of 2.6 predicted the presence of peritoneal metastasis with a specificity of 100% and a sensitivity of 71% and an overall accuracy of AUC = 0.81 (95%CI: 0.59-0.94), p = 0.05. PLR and PWR was not be associated to metastasis but tended to be associated to multifocal disease. CONCLUSION: In patients with midgut NET, an impaired adaptive immune response, as suggested by a high NLR ratio, was associated to the presence of distant metastasis and in particular of peritoneal metastasis. This information may be helpful when planning the treatment of a patient with a midgut NET.


Assuntos
Plaquetas/patologia , Procedimentos Cirúrgicos do Sistema Digestório , Neoplasias Intestinais/sangue , Neoplasias Intestinais/cirurgia , Linfócitos/patologia , Tumores Neuroendócrinos/sangue , Tumores Neuroendócrinos/cirurgia , Neutrófilos/patologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Curva ROC
2.
Eur Surg Res ; 60(5-6): 186-195, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31597147

RESUMO

BACKGROUND: Interferon gamma (IFNγ) and tumor necrosis factor-related weak inducer of apoptosis (TWEAK) molecules seem to have a potential effect on angiogenic factors such as vascular endothelial growth factor (VEGF). The aim of this study was to assess a possible interplay between IFNγ and TWEAK cytokines and VEGF machinery in the different steps of colorectal carcinogenesis. METHODS: A total of 92 subjects with colonic adenoma or cancer who underwent screening colonoscopy or surgery were prospectively enrolled. Polypoid lesion tissue samples were collected and frozen. Real-time reverse transcription polymerase chain reaction for IFNγ, TWEAK, and VEGF-A mRNA expression was performed. Immunoassays for VEGF-A, VEGF-C, VEGFR-1, VEGFR-2, and VEGFR-3 were also performed. Nonparametric statistics, receiver operating characteristic curve analysis, and logistic multiple regression analysis were used. RESULTS: IFNγ and TWEAK mRNA expression was higher in patients with T2 or more advanced colorectal cancer than in those with adenomas or T1 cancer (p < 0.001 and p = 0.01, respectively). IFNγ and TWEAK mRNA expression levels directly correlated with VEGF-A mRNA expression levels (rho = 0.44, p < 0.001 and rho = 0.29, p = 0.004, respectively). On the contrary, IFNγ and TWEAK mRNA expression levels inversely correlated with VEGF-C protein levels (rho = -0.29, p = 0.04 and rho = -0.31, p = 0.03, respectively). Similarly, IFNγ and TWEAK mRNA expression levels inversely correlated with VEGFR2 protein levels (rho = -0.38, p = 0.033 and rho = -0.40, p = 0.025, respectively). CONCLUSION: This study showed that in colorectal polypoid lesions, IFNγ and TWEAK expressions are directly correlated to VEGF-A expression but inversely correlated with VEGFR2 levels, suggesting a possible feedback mechanism in the regulation of VEGF-A expression.


Assuntos
Neoplasias Colorretais/irrigação sanguínea , Citocina TWEAK/genética , Interferon gama/genética , Neovascularização Patológica/etiologia , Fator A de Crescimento do Endotélio Vascular/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/etiologia , Citocina TWEAK/análise , Feminino , Humanos , Interferon gama/análise , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RNA Mensageiro/análise , Fator A de Crescimento do Endotélio Vascular/análise , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/análise
3.
Acta Chir Belg ; 118(1): 7-14, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28743216

RESUMO

BACKGROUND: Younger patients with colorectal cancer (CRC) generally have better survival in spite of worse clinical and pathological features. METHODS: Twenty-six patients under 50 years operated for primary CRC were enrolled and matched 1:2:2 according to stage, tumor site and gender with 52 patients from 50 to 70 years and 52 patients over 70 years old. RESULTS: Patients under 50 years had a significantly longer overall, cancer specific and disease free survival (p = .001, p = .007 and p = .05, respectively). However, they had more frequently lymphovascular invasion (p = .006) and they more frequently developed metachronous CRC at follow-up (p = .03). Nevertheless, preoperative lymphocytes blood count/white blood count (LBC/WBC) ratio inversely correlated with age at operation (rho = -.21, p = .04) and it predicted CRC recurrence with an accuracy of 70%, p < .001 (threshold value LBC/WBC = 0.21%) and better overall, cancer specific and disease free survival (p < .0001 for all). At multivariate analysis, stage and LBC/WBC ratio resulted independent predictors of disease free survival (p = .0001 and p = .01, respectively). CONCLUSIONS: Patients under 50 years had a significantly longer survival with a higher LBC/WBC ratio. These results could suggest a possible role of immunosurveillance in neoplastic control.


Assuntos
Adenocarcinoma/imunologia , Adenocarcinoma/mortalidade , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/mortalidade , Imunocompetência/fisiologia , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Fatores Etários , Idoso , Estudos de Coortes , Colectomia/métodos , Colectomia/mortalidade , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Intervalo Livre de Doença , Feminino , Humanos , Testes Imunológicos/métodos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Estudos Retrospectivos , Medição de Risco , Taxa de Sobrevida , Resultado do Tratamento
4.
Tumour Biol ; 39(3): 1010428317692263, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28347226

RESUMO

Colorectal cancer incidence in patients undergoing screening protocols is decreasing because of the higher rate of discovered preneoplastic colonic lesions; however, adenomatous polyps may not always be removable endoscopically and surgery may still be necessary. The aim of this study was to assess the vascular endothelial growth factor expression in the different steps of colorectal carcinogenesis to explore its potential role as a marker of malignancy in polypoid lesions. A total of 92 subjects with colonic adenoma or cancer who underwent screening colonoscopy or surgery were prospectively enrolled. Real-time reverse transcription polymerase chain reaction for VEGF-A messenger RNA expression and immunohistochemistry for VEGF-A were performed. Immunoassays for VEGF-A, VEGF-C, VEGFR-1, VEGFR-2, and VEGFR-3 were also performed. Non-parametric statistics, receiver operating characteristic curve analysis, and logistic multiple regression analysis were used. VEGF-A messenger RNA expression was higher in patients with high-grade dysplasia or colorectal cancer than in those with low-grade dysplasia adenomas (p = 0.01). At immunohistochemistry, VEGF-A expression was significantly higher in colorectal cancer patients compared to dysplastic adenomas (p < 0.001), and the accuracy of VEGF-A expression for prediction of malignancy was 91.7 (95% confidence interval = 78.7-97.9). VEGF-C protein expression was lower in colorectal cancer patients than in simple adenomas (p = 0.02). VEGF-A levels were directly correlated to polyp size (rho = 0.73, p = 0.0062). Multivariate analysis demonstrated that malignancy and polyp size were independent predictors of VEGF-A mucosal levels. This study demonstrated that the VEGF-A expression changes along the colorectal carcinogenesis pathway showing a neat step up at the passage from high-grade dysplasia to invasive cancer. This feature might potentially be useful to stratify colorectal polyps in different risks of progression classes. Moreover, the high level of VEGF-A expression predicted the presence of lymphovascular invasion with good accuracy.


Assuntos
Neoplasias Colorretais/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Estudos de Casos e Controles , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Fator A de Crescimento do Endotélio Vascular/genética
5.
Acta Chir Belg ; 116(4): 225-230, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27426670

RESUMO

BACKGROUND: The principal aim of endoscopic follow-up programs after curative resection of colorectal cancer (CRC) is to improve survival and identify local recurrence and metachronous CRC. The aim of our study was to identify the possible predictors of metachronous colorectal lesions. METHODS: The records of 348 consecutive patients with CRC and who completed at least 1 year of endoscopic follow-up after surgery were analyzed. In this group, 336 patients underwent surgery for primitive CRC and 12 for metachronous cancer. Patients' characteristics, operative details, and endoscopical follow-up findings were retrieved. Multivariate survival analyses were used to identify patient categories at risk of metachronous colonic lesions. RESULTS: 128 patients presented a metachronous lesion: 118 adenomas and 10 adenocarcinomas. At multivariate analysis, active smoke (HR = 1.84, p = 0.03), neoadjuvant therapy (HR = 0.24, p = 0.01), and presence of synchronous polyps (HR = 1.55, p = 0.04) resulted independent predictors of metachronous adenoma after CRC removal while neoadjuvant therapy (HR = 0.25, p = 0.02), active smoke (HR = 1.54, p = 0.04), and presence of synchronous polyps (HR = 1.86, p = 0.02) resulted independent predictors of metachronous lesions after CRC removal. CONCLUSIONS: This study demonstrated a high rate of metachronous lesions in the early follow-up after curative CRC resection. The negative effects of synchronous polyps should be carefully evaluated when planning patients' follow-up.


Assuntos
Adenocarcinoma/cirurgia , Neoplasias Colorretais/cirurgia , Neoplasias Primárias Múltiplas/epidemiologia , Segunda Neoplasia Primária/epidemiologia , Pólipos/patologia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Colectomia/efeitos adversos , Colectomia/métodos , Colonoscopia/métodos , Neoplasias Colorretais/patologia , Bases de Dados Factuais , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Neoplasias Primárias Múltiplas/patologia , Segunda Neoplasia Primária/patologia , Pólipos/mortalidade , Pólipos/cirurgia , Estudos Retrospectivos , Medição de Risco , Análise de Sobrevida , Resultado do Tratamento
6.
Ann Surg Oncol ; 22(6): 1933-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25564160

RESUMO

BACKGROUND: Two-stage hepatectomy (TSH) is well established for the treatment of patients who have colorectal cancer liver metastases (CRLM) with a small liver remnant. The technique of associating liver partitioning and portal vein occlusion for staged hepatectomy (ALPPS) has been advocated as a novel tool to increase resectability. Using a case-match design, this study aimed to compare TSH and ALPPS for patients with CRLM. METHODS: All patients undergoing ALPPS for CRLM at three major hepatobiliary centers in Italy (ALPPS group) were compared in a case-match analysis with patients undergoing TSH (TSH group) at a single institution. The groups were matched with a 1:3 ratio using propensity scores based on covariates representing severity of metastatic disease. The main end points of the study were feasibility of complete resection and intra- and postoperative outcomes. RESULTS: The two treatments did not differ significantly in feasibility. Two patients in the TSH group dropped out compared with no patients in the ALPPS group. A comparable volume gain in future liver remnant (FLR) was obtained in the ALPPS and TSH groups (47 vs. 41 %, nonsignificant difference) but during a shorter interval in ALPPS group. The overall and major complication rate was significantly higher after stage 2 in the ALPPS group (Clavien ≥ 3a: 41.7 vs. 17.6 % in TSH group; p = 0.025). CONCLUSION: The feasibility of resection using ALPPS compared with TSH for CRLM was not significantly greater, but perioperative complications were increased. Therefore, ALPPS should be proposed to patients with caution and warnings. Currently, TSH remains the standard approach for performing R0 resection in patients with advanced CRLM and inadequate FLR.


Assuntos
Neoplasias Colorretais/cirurgia , Hepatectomia/mortalidade , Neoplasias Hepáticas/cirurgia , Veia Porta/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Ligadura , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
7.
Hepatology ; 58(3): 1042-53, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23505219

RESUMO

UNLABELLED: Cholangiocarcinoma (CCA) is characterized by an abundant stromal reaction. Cancer-associated fibroblasts (CAFs) are pivotal in tumor growth and invasiveness and represent a potential therapeutic target. To understand the mechanisms leading to CAF recruitment in CCA, we studied (1) expression of epithelial-mesenchymal transition (EMT) in surgical CCA specimens and CCA cells, (2) lineage tracking of an enhanced green fluorescent protein (EGFP)-expressing human male CCA cell line (EGI-1) after xenotransplantation into severe-combined-immunodeficient mice, (3) expression of platelet-derived growth factors (PDGFs) and their receptors in vivo and in vitro, (4) secretion of PDGFs by CCA cells, (5) the role of PDGF-D in fibroblast recruitment in vitro, and (6) downstream effectors of PDGF-D signaling. CCA cells expressed several EMT biomarkers, but not alpha smooth muscle actin (α-SMA). Xenotransplanted CCA masses were surrounded and infiltrated by α-SMA-expressing CAFs, which were negative for EGFP and the human Y-probe, but positive for the murine Y-probe. CCA cells were strongly immunoreactive for PDGF-A and -D, whereas CAFs expressed PDGF receptor (PDGFR)ß. PDGF-D, a PDGFRß agonist, was exclusively secreted by cultured CCA cells. Fibroblast migration was potently induced by PDGF-D and CCA conditioned medium and was significantly inhibited by PDGFRß blockade with Imatinib and by silencing PDGF-D expression in CCA cells. In fibroblasts, PDGF-D activated the Rac1 and Cdc42 Rho GTPases and c-Jun N-terminal kinase (JNK). Selective inhibition of Rho GTPases (particularly Rac1) and of JNK strongly reduced PDGF-D-induced fibroblast migration. CONCLUSION: CCA cells express several mesenchymal markers, but do not transdifferentiate into CAFs. Instead, CCA cells recruit CAFs by secreting PDGF-D, which stimulates fibroblast migration through PDGFRß and Rho GTPase and JNK activation. Targeting tumor or stroma interactions with inhibitors of the PDGF-D pathway may offer a novel therapeutic approach.


Assuntos
Neoplasias dos Ductos Biliares/fisiopatologia , Ductos Biliares Intra-Hepáticos , Movimento Celular/fisiologia , Colangiocarcinoma/fisiopatologia , Fibroblastos/patologia , Linfocinas/fisiologia , Fator de Crescimento Derivado de Plaquetas/fisiologia , Proteínas rho de Ligação ao GTP/fisiologia , Animais , Antineoplásicos/farmacologia , Benzamidas/farmacologia , Neoplasias dos Ductos Biliares/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Colangiocarcinoma/patologia , Transição Epitelial-Mesenquimal/fisiologia , Xenoenxertos , Humanos , Mesilato de Imatinib , Técnicas In Vitro , Masculino , Camundongos , Camundongos SCID , Piperazinas/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais/fisiologia
8.
ACS Nano ; 18(26): 16622-16631, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38904174

RESUMO

Atomically precise graphene nanoribbons (GNRs) have a wide range of electronic properties that depend sensitively on their chemical structure. Several types of GNRs have been synthesized on metal surfaces through selective surface-catalyzed reactions. The resulting GNRs are adsorbed on the metal surface, which may lead to hybridization between the GNR orbitals and those of the substrate. This makes investigation of the intrinsic electronic properties of GNRs more difficult and also rules out capacitive gating. Here, we demonstrate the formation of a dielectric gold chloride adlayer that can intercalate underneath GNRs on the Au(111) surface. The intercalated gold chloride adlayer electronically decouples the GNRs from the metal and leads to a substantial hole-doping of the GNRs. Our results introduce an easily accessible tool in the in situ characterization of GNRs grown on Au(111) that allows for exploration of their electronic properties in a heavily hole-doped regime.

9.
Surg Endosc ; 27(8): 2911-20, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23468328

RESUMO

BACKGROUND: The purpose of this multicentric prospective study was to evaluate postoperative HRQL and satisfaction with care after laparoscopic colonic resection for colorectal cancer in elderly patients. METHODS: A total of 116 patients were enrolled in this study: 33 patients older than age 70 years had laparoscopic colectomy, whereas 24 had open colectomy; 44 patients younger than age 70 years had laparoscopic colectomy and 15 of them had open colectomy. The patients answered to three questionnaires about generic (EORTC QLQ C30) and disease-specific quality of life (EORTC CR29) and about treatment satisfaction (EORTC IN-PATSAT32). Nonparametric tests and forward stepwise multiple regression analysis were used for statistical analysis. RESULTS: One month after surgery, global quality of life (QL2 item) was significantly impaired in elderly patients who had laparoscopic colectomy compared with younger patients who had the same operation (p = 0.003). Similarly, role function (RF), physical function (PF), emotional function (EF), cognitive function (CF), and social function (SF) were impaired in elderly patients who had laparoscopic colectomy compared with younger patients (p < 0.001, p < 0.001, p = 0.013, p < 0.001, p = 0.01, respectively). Fatigue (FA), sleep disturbances (SL), appetite loss (AP), and dyspnea (DY) affected the quality of life of these patients more than younger patients (p < 0.001, p = 0.055, p = 0.051, and p = 0.003, respectively). CONCLUSIONS: Elderly patients undergoing laparoscopic colectomy for cancer experience less postoperative local complications than elderly patients undergoing open colectomy. Nevertheless, in the first postoperative month, these patients experience a worse global quality of life than younger patients undergoing the same operation with impairment of all the functions and the presence of fatigue, sleep disturbances, appetite loss, and dyspnea.


Assuntos
Neoplasias Colorretais/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Satisfação do Paciente , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/psicologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários , Resultado do Tratamento
10.
Hepatology ; 54(3): 890-9, 2011 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21618579

RESUMO

UNLABELLED: Cholangiocarcinoma (CCA) carries a severe prognosis because of its strong invasiveness and early metastasization. In several patients, otherwise eligible for surgical resection, micrometastasis are already present at the time of surgery. The mechanisms responsible for CCA invasiveness are unclear. S100A4, a member of the S100 family of small Ca(2+)-binding proteins, is expressed in mesenchymal cells, regulates cell motility in several cell types, and is expressed in some epithelial cancers. Thus, we aimed to study the role of S100A4 in CCA invasiveness and metastasization. The expression of S100A4 was studied by immunohistochemistry in 93 human liver samples of CCA patients undergoing surgical resection and correlated with metastases development (67 cases) and patient survival following surgery using log rank tests and multivariate analysis. S100A4 expression was studied in EGI-1 and TFK-1, human CCA cell lines with and without nuclear S100A4 expression, respectively. Metastatic properties of CCA cells were assessed by xenotransplantation in severe combined immunodeficiency (SCID) mice after transduction with lentiviral vectors encoding firefly luciferase gene. Proliferation, motility (wound healing), invasiveness (Boyden chamber), and metalloproteinases (MMPs) secretion were studied in CCA cells, with or without lentiviral silencing of S100A4. Nuclear expression of S100A4 by neoplastic ducts was a strong predictor of metastasization and reduced survival after resection (P < 0.01). EGI-1 CCA cells showed stronger metastatic properties than TFK-1 when xenotransplanted in SCID mice. S100A4-silenced EGI-1 cells showed significantly reduced motility, invasiveness, and MMP-9 secretion in vitro, without changes in cell proliferation. CONCLUSION: Nuclear S100A4 identifies a subset of CCA patients with a poor prognosis after surgical resection. Nuclear expression of S100A4 increases CCA cells invasiveness and metastasization, indicating that S100A4 may also represent a potential therapeutic target.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos , Núcleo Celular/química , Colangiocarcinoma/patologia , Proteínas S100/fisiologia , Idoso , Animais , Apoptose , Neoplasias dos Ductos Biliares/química , Neoplasias dos Ductos Biliares/cirurgia , Movimento Celular , Proliferação de Células , Colangiocarcinoma/química , Colangiocarcinoma/cirurgia , Feminino , Humanos , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Prognóstico , Proteína A4 de Ligação a Cálcio da Família S100 , Proteínas S100/análise
11.
Commun Chem ; 4(1): 51, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36697612

RESUMO

Achieving fundamental understanding of enantioselective heterogeneous synthesis is marred by the permanent presence of multitudinous arrangements of catalytically active sites in real catalysts. In this study, we address this issue by using structurally comparatively simple, well-defined, and chiral intermetallic PdGa{111} surfaces as catalytic substrates. We demonstrate the impact of chirality transfer and ensemble effect for the thermally activated azide-alkyne Huisgen cycloaddition between 3-(4-azidophenyl)propionic acid and 9-ethynylphenanthrene on these threefold symmetric intermetallic surfaces under ultrahigh vacuum conditions. Specifically, we encounter a dominating ensemble effect for this reaction as on the Pd3-terminated PdGa{111} surfaces no stable heterocoupled structures are created, while on the Pd1-terminated PdGa{111} surfaces, the cycloaddition proceeds regioselectively. Moreover, we observe chirality transfer from the substrate to the reaction products, as they are formed enantioselectively on the Pd1-terminated PdGa{111} surfaces. Our results evidence a determinant ensemble effect and the immense potential of PdGa as asymmetric heterogeneous catalyst.

12.
ACS Appl Nano Mater ; 3(12): 12178-12187, 2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33392466

RESUMO

Graphdiyne, atomically thin two-dimensional (2D) carbon nanostructure based on sp-sp2 hybridization is an appealing system potentially showing outstanding mechanical and optoelectronic properties. Surface-catalyzed coupling of halogenated sp-carbon-based molecular precursors represents a promising bottom-up strategy to fabricate extended 2D carbon systems with engineered structure on metallic substrates. Here, we investigate the atomic-scale structure and electronic and vibrational properties of an extended graphdiyne-like sp-sp2 carbon nanonetwork grown on Au(111) by means of the on-surface synthesis. The formation of such a 2D nanonetwork at its different stages as a function of the annealing temperature after the deposition is monitored by scanning tunneling microscopy (STM), Raman spectroscopy, and combined with density functional theory (DFT) calculations. High-resolution STM imaging and the high sensitivity of Raman spectroscopy to the bond nature provide a unique strategy to unravel the atomic-scale properties of sp-sp2 carbon nanostructures. We show that hybridization between the 2D carbon nanonetwork and the underlying substrate states strongly affects its electronic and vibrational properties, modifying substantially the density of states and the Raman spectrum compared to the free standing system. This opens the way to the modulation of the electronic properties with significant prospects in future applications as active nanomaterials for catalysis, photoconversion, and carbon-based nanoelectronics.

13.
Gastrointest Endosc ; 70(2): 212-24, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19409558

RESUMO

BACKGROUND: Advances in medical practice in recent decades have influenced the etiology and management of acute upper-GI bleeding (UGIB), but their impact on the incidence and mortality is unclear. OBJECTIVE: To analyze the time trends of UGIB in 2 different management eras. DESIGN: Prospective observational study. SETTING: General university-affiliated hospital. PATIENTS AND INTERVENTIONS: A total of 587 patients who presented with UGIB during the 1983-to-1985 period were compared with 539 patient in the 2002-to-2004 period. RESULTS: The overall incidence of UGIB decreased from 112.5 to 89.8 per 100,000/y, which corresponds to a 35.5% decrease after adjustment for age (95% CI, 24.2%-46.8%). The age standardized incidence of ulcer bleeding decreased by 41.6% (95% CI, 27.2%-56%); the decrease occurred only in people younger than 70 years of age. The rate of history of peptic ulcer disease decreased from 32.7% in the 1983-to-1985 period versus 19.5% in the 2002-to-2004 period (P < .001). The mean age increased from 61.0 to 68.7 years (P < .001), and the male:female ratio decreased from 2.7 to 1.8 (P = .002). The comorbidities increased from 69% to 75% (P = .01), the use of nonsteroidal anti-inflammatory drugs from 40.0% to 46.4% (P = .03), and the cases of bleeding occurring during hospitalization from 10.4% to 17.1% (P < .001). In the 1983-to-1985 cohort, the endoscopy was solely diagnostic, and antisecretory therapy consisted of H2-antagonists drugs. In the second period, 39.3% of patients underwent endoscopic therapy, whereas proton pump inhibitors were administered in 47%. Rebleeding rates decreased from 32.5% to 7.4% (P < .001) and surgery from 10.2% to 2.0% (P < .001). Overall mortality decreased from 17.1 to 8.2 per 100,000/y, which corresponded to a 60.8% decrease after adjustment for age (95% CI, 46.5%-75.1%). The age standardized mortality rate for ulcer bleeding decreased by 56.5% (95% CI, 41.9%-71.1%). LIMITATIONS: A single-center study and a potential lack of generalizability. CONCLUSIONS: From the 1983-to-1985 period to the 2002-to-2004 period, major changes occurred in the incidence of UGIB, features of patients, management, and outcomes. The incidence and mortality of UGIB overall and ulcer bleeding decreased significantly, and the decline of incidence occurred only in patients younger than 70 years old.


Assuntos
Hemorragia Gastrointestinal/epidemiologia , Doença Aguda , Idoso , Endoscopia Gastrointestinal , Feminino , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo
14.
JOP ; 10(1): 48-52, 2009 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-19129615

RESUMO

CONTEXT: Hemosuccus pancreaticus is a rare cause of upper chronic and intermittent gastrointestinal hemorrhage which cannot be easily detected by endoscopy. It is usually due to the rupture of a visceral aneurysm into the main pancreatic duct; splenic artery pseudoaneurysm associated with chronic pancreatitis represents the leading cause of this condition. The diagnosis is based on direct visualization of the hemorrhage through the main pancreatic duct at angiography. Given its rarity, difficulties in determining the source of bleeding can result in delayed treatment. CASE REPORT: We present a rare case of true splenic artery aneurysm fistulized in the main pancreatic duct and misdiagnosed as a bleeding pancreatic pseudocyst on preoperative examination which included CT and MRCP. CONCLUSIONS: Our experience confirms that the diagnosis of bleeding from the main pancreatic duct is very difficult. It requires careful and repeated evaluation by a team of specialists.


Assuntos
Aneurisma/diagnóstico , Hemorragia Gastrointestinal/diagnóstico , Hemorragia/diagnóstico , Pancreatopatias/diagnóstico , Pancreatopatias/terapia , Artéria Esplênica , Aneurisma/complicações , Aneurisma/patologia , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Hemorragia/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatopatias/complicações , Artéria Esplênica/patologia
16.
BMJ Case Rep ; 20172017 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-28104721

RESUMO

Gastrointestinal stromal tumours (GISTs) can arise everywhere along the gastrointestinal (GI) tract. Their presentation in unusual locations should always be taken into account. A 74-year-old man referred to the emergency department for small bowel obstruction caused by an incarcerated inguinal hernia. A CT scan showed a mesenchymal tumour originating from the herniated bowel loop and a mass in the ascending colon. Laparoscopic resection of the mass and laparoscopic right hemicolectomy were performed. The histology showed a ruptured GIST arising from the herniated small bowel and a high-grade dysplasia villous adenoma of the right colon. GISTs can present with symptoms spanning from vague abdominal discomfort to surgical urgencies. Strangulated hernia is an extremely rare presentation, with only two cases described in the literature. A safe surgical approach was obtained with laparoscopy, maintaining surgical radicality. The ileal localisation and the pseudocapsule rupture were the main risk factors on prognostic stratification.


Assuntos
Adenoma Viloso/diagnóstico por imagem , Neoplasias do Colo/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Hérnia Inguinal/diagnóstico por imagem , Neoplasias do Íleo/diagnóstico por imagem , Obstrução Intestinal/diagnóstico por imagem , Neoplasias Primárias Múltiplas/diagnóstico por imagem , Adenoma Viloso/complicações , Adenoma Viloso/patologia , Adenoma Viloso/cirurgia , Idoso , Colectomia , Neoplasias do Colo/complicações , Neoplasias do Colo/patologia , Neoplasias do Colo/cirurgia , Tumores do Estroma Gastrointestinal/complicações , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/cirurgia , Hérnia Inguinal/complicações , Humanos , Neoplasias do Íleo/classificação , Neoplasias do Íleo/patologia , Neoplasias do Íleo/cirurgia , Obstrução Intestinal/etiologia , Masculino , Neoplasias Primárias Múltiplas/complicações , Neoplasias Primárias Múltiplas/patologia , Neoplasias Primárias Múltiplas/cirurgia , Tomografia Computadorizada por Raios X
17.
Mol Clin Oncol ; 7(4): 529-538, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28855987

RESUMO

The aim of the present study was to evaluate the risk factors for postoperative complications following liver resection for colorectal cancer liver metastases. Patients who underwent hepatic resection for colorectal cancer liver metastases were stratified according to chemotherapy administration and body mass index (BMI) to eliminate potential confounding factors. A univariate analysis was conducted to identify potential risk factors for postoperative complications following liver resection. Variables that exhibited a potential association were evaluated by multivariable logistic regression analysis to identify those independently associated with postoperative morbidity. Between January 2012 and March 2012, 100 patients underwent hepatic resection for liver metastases from colorectal carcinoma at the Treviso Regional Hospital (Treviso, Italy) and at the Regina Elena National Cancer Institute (Rome, Italy). Of the 100 patients, 61 received preoperative oxaliplatin- or irinotecan-based chemotherapy. A total of 25 the patients had a BMI of ≥28 kg/m2. On univariate analysis, BMI ≥28 kg/m2 was found to be positively correlated with the presence of steatosis (P<0.01) and steatohepatitis (P<0.01). The administration of preoperative chemotherapy was correlated with the development of steatosis (P<0.01), steatohepatitis (P=0.02) and postoperative complications (P=0.03). Even following stratification for the use of preoperative chemotherapy, BMI ≥28 kg/m2 maintained its positive association with steatohepatitis. On multivariate analysis, steatohepatitis (P=0.005, HR=0.118, 95% CI: 0.027-0.518) and blood transfusions (P=0.001, HR=0.131, 95% CI: 0.038-0.452) were independently associated with postoperative complications. BMI ≥28 kg/m2 (P=0.004, HR=8.30, 95% CI: 2.39-28.7) and irinotecan treatment (P=0.016, HR=0.16, 95% CI: 0.037-0.711) were independent risk factors for steatohepatitis. In conclusion, steatohepatitis and perioperative blood transfusions were found to be the main determinant of postoperative complications following liver resection for colorectal liver metastases. Overweight patients may be more prone to the cytotoxic effects of irinotecan, harboring a higher risk of developing steatohepatitis.

19.
Anticancer Res ; 36(4): 1447-60, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27069120

RESUMO

Inflammatory bowel diseases (IBD) are associated with an increased risk of colitis-associated colorectal carcinoma (CAC). CAC is one of the most important causes of morbidity and mortality in patients with Crohn's disease and ulcerative colitis. The aim of the present review was to discuss the most important signaling pathways and genetic alterations involved in carcinogenesis related to IBD, focusing on the molecular aspects of cancer stem cell physiology and the impact of the inflammatory microenvironment. Molecular mechanisms involved in CAC development differ from those in sporadic colorectal cancer, reflecting the prominent role of inflammation-induced carcinogenesis in the development of CAC. The alteration of the physiological microenvironment is thought to be responsible for the initiation of carcinogenesis in IBD. Furthermore, cancer stem cells seem to have a fundamental role in the generation and growth of CAC. We also address prevention and treatment modalities of CAC and its involvement in IBD.


Assuntos
Neoplasias Colorretais/etiologia , Doenças Inflamatórias Intestinais/complicações , Animais , Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/prevenção & controle , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/imunologia
20.
Cancer Biol Ther ; 17(9): 889-98, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27414952

RESUMO

Inflammatory bowel diseases are an increasing phenomenon in western countries and in growing populations. The physiopathology of these conditions is linked to intestinal stem cells homeostasis and regenerative potential in a chronic inflammatory microenvironment. Patients with IBD present an increased risk of developing colorectal cancer (CRC), or colitis associated cancer (CAC). Conventional treatment for IBD target the inflammatory process (and include anti-inflammatory and immunosuppressive drugs) with biological agents emerging as a therapeutic approach for non-responders to traditional therapy. Conventional treatment provides scarce results and present severe complications. The intestinal environment may host incoming stem cells, able to engraft in the epithelial damaged sites and differentiate. Therefore, stem cell therapies represent an emerging alternative in inflammatory bowel diseases, with current investigations on the use of haematopoietic and mesenchymal stem cells, in particular adipose stem cells, apparently fundamental as regenerators and as immune-modulators. Here, we discuss stem cells in intestinal homeostasis and as therapeutic agents for the treatment of inflammatory bowel diseases.


Assuntos
Adipócitos/transplante , Doenças Inflamatórias Intestinais/patologia , Doenças Inflamatórias Intestinais/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/patologia , Adipócitos/patologia , Animais , Humanos
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