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1.
Phys Chem Chem Phys ; 19(22): 14319-14336, 2017 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-28537623

RESUMO

Enhanced conductivity in YSZ films has been of substantial interest over the last decade. In this paper we examine the effects of substrate lattice mismatch and film thickness on the strain in YSZ films and the resultant effect on the conductivity. 8 mol% YSZ films have been grown on MgO, Al2O3, LAO and NGO substrates, thereby controlling the lattice mismatch at the film/substrate interface. The thickness of the films was varied to probe the interfacial contribution to the transport properties, as measured by impedance spectroscopy and tracer diffusion. No enhancement in the transport properties of any of the films was found over single crystal values, and instead the effects of lattice strain were found to be minimal. The interfaces of all films were more resistive due to a heterogeneous distribution of grain boundaries, and no evidence for enhanced transport down dislocations was found.

2.
Anticancer Drugs ; 26(2): 123-38, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25406023

RESUMO

Gastric cancer is one of the most dreadful neoplastic diseases and remains the second cause of cancer death worldwide. Patients who develop peritoneal metastasis have a poor prognosis, with a median survival of less than 6 months. Despite being the cause of 60% of deaths from gastric cancer, peritoneal metastasis can still be considered a local disease and a local multidisciplinary approach can improve the prognosis even in this end-stage disease. At present, hyperthermic intraperitoneal chemotherapy (HIPEC) is the most widely accepted treatment for peritoneal surface diseases and can be performed in patients with different stages of cancer and with various antitumoral drugs. We performed a systematic review of the current status of HIPEC in the treatment of gastric peritoneal metastasis in an attempt to obtain answers to the questions that still remain: do results differ with these different methods? Does HIPEC exert a significant effect on the intracavitary delivery of drugs? Which patients should be treated and which should not? What can we expect from this approach in terms of survival, morbidity, and mortality? On reviewing the literature, despite the lack of trials comparing the different methods, we found that HIPEC has been shown to be an effective tool whenever a complete or an almost complete resection of the peritoneal implants can be performed. Therefore, it is advisable to refer all at-risk patients to specialized centers to be enrolled in randomized trials to achieve truly reliable results.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Hipertermia Induzida/métodos , Neoplasias Peritoneais/terapia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Humanos , Hipertermia Induzida/efeitos adversos , Terapia Neoadjuvante , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/patologia , Neoplasias Peritoneais/secundário , Neoplasias Peritoneais/cirurgia , Cuidados Pré-Operatórios , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
3.
Front Surg ; 11: 1356409, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38633884

RESUMO

Introduction: Gastric antral vascular ectasia (GAVE) is a rare cause of chronic or acute gastrointestinal bleeding. This condition accounts for ∼4% of upper gastrointestinal bleeding cases. This disease is often associated with systemic diseases, such as liver cirrhosis, chronic kidney failure, autoimmune conditions, diabetes mellitus, hypothyroidism, and cardiovascular diseases. However, its etiopathogenesis remains controversial. Materials and method: We retrospectively reviewed the cases of GAVE treated at our digestive surgery unit. A total of nine patients were identified with a male/female ratio of 1.25:1 and an average age of 75.51 years (SD ± 9.85). All patients underwent endoscopic argon plasma coagulation (APC) treatment. At the time of the review, data on eight patients were available after 36 months of follow-up. Results: APC appears to be safe and effective for hemostasis of bleeding vascular ectasia. Only one (11.1%) patient required surgical intervention due to hemodynamic instability after multiple unsuccessful endoscopic treatments. No intraoperative and postoperative complication or bleeding relapse was experienced. Discussion: Based on our findings, we concluded that endoscopic APC is technically simple, but requires multiple re-interventions due to the incidence of relapses. Furthermore, larger randomized studies should be conducted to assess the role of elective surgery as the first intervention in stable patients with severe pathology and the timing of surgery after failed endoscopic treatment.

4.
Front Surg ; 11: 1423222, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38948483

RESUMO

The transoral endoscopic thyroidectomy vestibular approach (TOETVA) is an innovative technique in thyroid surgery. This review compiles current research on TOETVA, covering its development, anatomical challenges, techniques, selection of suitable patients, results, complications, and future advancements. We performed a comprehensive literature review on PubMed, EMBASE, and Cochrane databases for articles published up to 15th March 2024. The search strategy included a combination of terms focused on "vestibular approach" and "thyroidectomy". The review underscores the necessity for preoperative planning and careful patient selection to reduce risks and enhance outcomes. It discusses the unique anatomical challenges of TOETVA, such as avoiding mental nerve damage and the complexities involved in creating a subplatysmal space. Outcomes of TOETVA, including surgical duration, complication rates, and recovery times, are compared favorably to traditional methods. The approach is particularly noted for high patient satisfaction and superior cosmetic results. Complications specific to TOETVA, like infection, bleeding, and potential harm to the recurrent laryngeal nerve, are recognized. Future research directions are discussed as well. In summary, TOETVA is a promising alternative for thyroidectomy with excellent cosmetic outcomes and patient satisfaction. Success relies on selective patient criteria, surgical expertise, and continuous research to refine the approach.

5.
World J Surg Oncol ; 11: 172, 2013 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-23914945

RESUMO

BACKGROUND: Gastrointestinal stromal tumors (GISTs) represent 85% of all mesenchymal neoplasms that affect the gastrointestinal (GI) tract. These GISTs range in size from small lesions to large masses. Often they are clinically silent until they reach a significant size, so their discovery is usually incidental. CASE PRESENTATION: A 67-year-old man was admitted at our general surgery department with a persistent abdominal pain in the left hypochondrium, associated with nausea and vomiting. Clinical examination revealed a palpable mass in the epigastrium and in the left hypochondrium, which was approximately 40 cm long. Ultrasonography and computed tomography of the abdomen showed a large mass of 40 × 25 cm, which extended from the posterior wall of the stomach to the spleen, involving the body and the tail of the pancreas. The patient underwent en-block resection of the mass, sleeve resection of the stomach, and distal pancreatectomy-splenectomy. The histopathology of the resected specimen was consistent with a gastrointestinal stromal tumor of the stomach (positive for CD 117) with a high risk of malignancy (mitotic count >5/50 high-power fieldand Ki67/Mib1 >10%). The postoperative course was uneventful and treatment with imatinib mesylate began immediately. The patient appears to be disease free after four years. CONCLUSIONS: Giant GISTs of the stomach are rare. Surgical resection with curative intent is feasible. The combination of surgical resection and imatinib can provide long-termdisease-free survival. An R0 resection is the best achievable treatment, therefore the patient should be evaluated over time for potential resectability.


Assuntos
Gastrectomia , Tumores do Estroma Gastrointestinal/cirurgia , Obstrução Intestinal/complicações , Pancreatectomia , Esplenectomia , Neoplasias Gástricas/cirurgia , Idoso , Tumores do Estroma Gastrointestinal/diagnóstico , Tumores do Estroma Gastrointestinal/etiologia , Humanos , Masculino , Prognóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/etiologia , Tomografia Computadorizada por Raios X
6.
BMC Surg ; 13 Suppl 2: S2, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24268048

RESUMO

BACKGROUND: Breast cancer (BC) remains principally a disease of old ages; with 35-50% of cases occurring in women older than 65 years. Even mortality for cancer increases with aging: 19.7% between 65 and 74 years; 22.6% between 75 and 84 years; and 15.1% in 85 years or more. METHODS: A search was performed on Medline, Embase, Scopus using the following Key words: Breast cancer, Breast neoplasms, Aged, Elder, Elderly, Eldest, Older, Survival analysis, Prognosis, Prognostic factors, Tumor markers, Biomarkers, Comorbidity, Geriatric assessment, Axilla, Axillary surgery. 3029 studies have been retrieved. Paper in which overall or disease free survival were not end points, or age class was not well defined, or the sample was too small, were excluded. At last 42 papers fulfilled the criteria. RESULTS AND DISCUSSION: Lack of screening and delay in diagnosis may be responsible for the minor improvement in survival observed in elderly respect to younger breast cancer patients. Predictive factors are the same and must be assessed with the same attention reserved to younger women. CONCLUSIONS: Most of elderly patient are fit to undergo standard treatment and can get the same benefits of younger women. Nevertheless it is possible that some older women with early breast cancer can be spared too aggressive treatments. Geriatric assessment and co-morbidities can affect the prognosis modifying surveillance, life expectancy and compliance to therapies. They can thus be useful to select the better treatment, either surgical or radio or hormone - or chemo-therapy.


Assuntos
Neoplasias da Mama/mortalidade , Idoso , Feminino , Humanos , Prognóstico , Taxa de Sobrevida
7.
J Clin Med ; 12(5)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36902740

RESUMO

BACKGROUND: Hypoparathyroidism is one of the most common complications after thyroidectomy. This study evaluated the incidence and potential risk factors for postoperative hypoparathyroidism after thyroid surgical procedures in a single high-volume center. METHODS: In this retrospective study, in all patients undergoing thyroid surgery from 2018 to 2021, a 6 h postoperative parathyroid hormone level (PTH) was evaluated. Patients were divided into two groups based on 6 h postoperative PTH levels (≤12 and >12 pg/mL). RESULTS: A total of 734 patients were enrolled in this study. Most patients (702, 95.6%) underwent a total thyroidectomy, while 32 patients underwent a lobectomy (4.4%). A total of 230 patients (31.3%) had a postoperative PTH level of <12 pg/mL. Postoperative temporary hypoparathyroidism was more frequently associated with female sex, age < 40 y, neck dissection, the yield of lymph node dissection, and incidental parathyroidectomy. Incidental parathyroidectomy was reported in 122 patients (16.6%) and was correlated with thyroid cancer and neck dissection. CONCLUSIONS: Young patients undergoing neck dissection and with incidental parathyroidectomy have the highest risk of postoperative hypoparathyroidism after thyroid surgery. However, incidental parathyroidectomy did not necessarily correlate with postoperative hypocalcemia, suggesting that the pathogenesis of this complication is multifactorial and may include an impaired blood supply to parathyroid glands during thyroid surgery.

8.
World J Clin Cases ; 10(27): 9734-9742, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36186197

RESUMO

BACKGROUND: Gallbladder hemorrhage is a life-threatening disorder. Trauma (accidental or iatrogenic such as a percutaneous biopsy or cholecystectomy surgery), cholelithiasis, biliary tract parasitosis, vasculitis, vascular malformations, autoimmune and neoplastic diseases and coagulopathies have been described as causes of hemorrhage within the lumen of the gallbladder. The use of non-steroidal anti-inflammatory drugs and anticoagulants may represent a risk factor. CASE SUMMARY: We report the case of a 76-year-old male patient. An urgent contrast computed tomography scan demonstrated relevant distension of the gallbladder filled with hyperdense non-homogeneous content. The gallbladder walls were of regular thickness. Near the anterior wall a focus of suspected active bleeding was observed. Due to the progressive decrease in hemoglobin despite three blood transfusions, this was an indication for urgent surgery. CONCLUSION: Early diagnosis of this potentially fatal pathology is essential in order to plan a strategy and eventually proceed with urgent surgical treatment.

9.
ACS Appl Mater Interfaces ; 14(16): 18486-18497, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35412787

RESUMO

Ion intercalation of perovskite oxides in liquid electrolytes is a very promising method for controlling their functional properties while storing charge, which opens up its potential application in different energy and information technologies. Although the role of defect chemistry in oxygen intercalation in a gaseous environment is well established, the mechanism of ion intercalation in liquid electrolytes at room temperature is poorly understood. In this study, the defect chemistry during ion intercalation of La0.5Sr0.5FeO3-δ thin films in alkaline electrolytes is studied. Oxygen and proton intercalation into the La1-xSrxFeO3-δ perovskite structure is observed at moderate electrochemical potentials (0.5 to -0.4 V), giving rise to a change in the oxidation state of Fe (as a charge compensation mechanism). The variation of the concentration of holes as a function of the intercalation potential is characterized by in situ ellipsometry, and the concentration of electron holes is indirectly quantified for different electrochemical potentials. Finally, a dilute defect chemistry model that describes the variation of defect species during ionic intercalation is developed.

10.
World J Emerg Surg ; 17(1): 61, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36527038

RESUMO

BACKGROUND: The incidence of the highly morbid and potentially lethal gangrenous cholecystitis was reportedly increased during the COVID-19 pandemic. The aim of the ChoCO-W study was to compare the clinical findings and outcomes of acute cholecystitis in patients who had COVID-19 disease with those who did not. METHODS: Data were prospectively collected over 6 months (October 1, 2020, to April 30, 2021) with 1-month follow-up. In October 2020, Delta variant of SARS CoV-2 was isolated for the first time. Demographic and clinical data were analyzed and reported according to the STROBE guidelines. Baseline characteristics and clinical outcomes of patients who had COVID-19 were compared with those who did not. RESULTS: A total of 2893 patients, from 42 countries, 218 centers, involved, with a median age of 61.3 (SD: 17.39) years were prospectively enrolled in this study; 1481 (51%) patients were males. One hundred and eighty (6.9%) patients were COVID-19 positive, while 2412 (93.1%) were negative. Concomitant preexisting diseases including cardiovascular diseases (p < 0.0001), diabetes (p < 0.0001), and severe chronic obstructive airway disease (p = 0.005) were significantly more frequent in the COVID-19 group. Markers of sepsis severity including ARDS (p < 0.0001), PIPAS score (p < 0.0001), WSES sepsis score (p < 0.0001), qSOFA (p < 0.0001), and Tokyo classification of severity of acute cholecystitis (p < 0.0001) were significantly higher in the COVID-19 group. The COVID-19 group had significantly higher postoperative complications (32.2% compared with 11.7%, p < 0.0001), longer mean hospital stay (13.21 compared with 6.51 days, p < 0.0001), and mortality rate (13.4% compared with 1.7%, p < 0.0001). The incidence of gangrenous cholecystitis was doubled in the COVID-19 group (40.7% compared with 22.3%). The mean wall thickness of the gallbladder was significantly higher in the COVID-19 group [6.32 (SD: 2.44) mm compared with 5.4 (SD: 3.45) mm; p < 0.0001]. CONCLUSIONS: The incidence of gangrenous cholecystitis is higher in COVID patients compared with non-COVID patients admitted to the emergency department with acute cholecystitis. Gangrenous cholecystitis in COVID patients is associated with high-grade Clavien-Dindo postoperative complications, longer hospital stay and higher mortality rate. The open cholecystectomy rate is higher in COVID compared with non -COVID patients. It is recommended to delay the surgical treatment in COVID patients, when it is possible, to decrease morbidity and mortality rates. COVID-19 infection and gangrenous cholecystistis are not absolute contraindications to perform laparoscopic cholecystectomy, in a case by case evaluation, in expert hands.


Assuntos
COVID-19 , Colecistite Aguda , Colecistite , Sepse , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Pandemias , SARS-CoV-2 , COVID-19/epidemiologia , Colecistite/epidemiologia , Colecistite/cirurgia , Colecistite Aguda/epidemiologia , Colecistite Aguda/cirurgia , Complicações Pós-Operatórias/epidemiologia
11.
Surg Today ; 41(1): 141-6, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21191708

RESUMO

Benign multicystic peritoneal mesothelioma (BMPM) is a rare disease with good short-term prognosis and rare malignant transformation. However, its biological significance remains unexplained. A neoplastic origin is considered by many authors to require a surgical excision, based on the high recurrence and progressive growth rate of the tumors. However, alternative or integrative treatment options have also been proposed. A 45-year-old woman presented to our unit with a history of occasional discomfort and pain in the left hip. On physical examination, we noticed a tough-elastic, fixed mass located in the iliac fossa. Computed tomography scan detected a mass with multiseptated cystic-like areas. Due to the similarity of these findings to a primitive sarcomatous tumor of the retroperitoneum, an arteriographic study was also performed. The patient underwent en bloc resection of the mass, including a segment of the sigmoid colon. The final pathologic diagnosis was cystic mesothelioma. Further studies are needed to better understand the etiology and pathogenesis of this rare disease, and to define a more tailored treatment plan.


Assuntos
Mesotelioma Cístico/diagnóstico , Mesotelioma Cístico/cirurgia , Neoplasias Peritoneais/diagnóstico , Neoplasias Peritoneais/cirurgia , Feminino , Humanos , Mesotelioma Cístico/complicações , Pessoa de Meia-Idade , Neoplasias Peritoneais/complicações
12.
Ann Ital Chir ; 82(6): 437-42, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22229231

RESUMO

Aimed to evaluate the postoperative pain and other complications among two cohorts of patients undergone transabdominal preperitoneal (TAPP) and totally extraperitoneal (TEP) laparoscopic hernia repairs with mechanical fixation, the chart of 305 TAPP and 134 TEP for bilateral not recurrent inguinal hernias were reviewed. The postoperative pain was assessed by using the Verbal Rating Scale (VRS) at one week, one month, 3 months ad six months postoperatively. A subgroup of 60 patients was also administered the QoL EQ-5D questionnaire and follow up for at least 6 months. We found a statistically significant difference in the first day (p = 0.001), in the 7th day (p = 0.002), 30th, and 90th day (p = 0.008) between patients perception of pain in TAPP group and TEP group, but after the 180th day there was not any considerable distinction. On the short term the postoperative pain seems slightly lesser in TEP group.


Assuntos
Hérnia Inguinal/cirurgia , Herniorrafia/métodos , Laparoscopia/métodos , Dor Pós-Operatória/diagnóstico , Qualidade de Vida , Adulto , Idoso , Feminino , Seguimentos , Hérnia Inguinal/patologia , Herniorrafia/efeitos adversos , Humanos , Laparoscopia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
13.
Ann Ital Chir ; 82(5): 383-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21988046

RESUMO

BACKGROUND: Mesenteric and duodenal leiomyosarcomas are very rare malignancies. Muscular metastases from leiomyosarcoma are even more rare. Surgery is the only chance of cure and should be attempted whenever possible. The relief of symptoms and the prevention of recurrences are ultimately the aims of surgery. We present a unique case of mesocolic and duodenal leiomyosarcoma with muscular metastases. CASE REPORT: A 61 year old woman was treated by radical resection including left neftectomy and left hemicolectomy for a leiomyosarcoma of the left mesocolon. Three years after the first surgery a leiomyosarcoma of the duodenal wall was diagnosed. Following a careful evaluation that ruled out the presence of other secondary locations, she underwent pancreatoduodenectomy. Three months later she observed a small, mildly painful swelling in the left thigh, rapidly growing to a diameter of 4 cm over a month period. The MRI showed a low-signal intensity malignancy in T2-weighted images whereas the lesion was homogeneously enhanced by Gadolinium on T1-weighted imaging. The histological examination after excision confirmed the clinical suspicion of a metastasis from high grade leiomyosarcoma. Successively the patient underwent a palliative chemotherapy treatment with epirubicin and ifosfamide for three cycles. The patient experienced a progression of disease with multiple pulmonary and encephalic metastases five months later. CONCLUSION: Muscular metastases from leiomyosarcoma are occasionally described in the literature. The apparition of muscular metastases is considered a negative prognostic factor and shortly precedes massive distant diffusion of the malignancy. Denervation syndrome can be a risk factor for muscular metastases. To our knowledge, this is the first report of a skeletal-muscle metastasis following mesenteric and duodenal leiomyosarcoma.


Assuntos
Neoplasias Duodenais/patologia , Leiomiossarcoma/secundário , Mesocolo/patologia , Neoplasias Musculares/secundário , Neoplasias Primárias Múltiplas/patologia , Neoplasias Peritoneais/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Progressão da Doença , Neoplasias Duodenais/tratamento farmacológico , Neoplasias Duodenais/cirurgia , Feminino , Humanos , Leiomiossarcoma/tratamento farmacológico , Leiomiossarcoma/cirurgia , Pessoa de Meia-Idade , Neoplasias Musculares/tratamento farmacológico , Neoplasias Musculares/cirurgia , Invasividade Neoplásica , Neoplasias Primárias Múltiplas/tratamento farmacológico , Neoplasias Primárias Múltiplas/cirurgia , Cuidados Paliativos , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/cirurgia , Prognóstico , Coxa da Perna/patologia
14.
IEEE Trans Image Process ; 30: 8075-8087, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34543196

RESUMO

We present an adversarial framework to craft perturbations that mislead classifiers by accounting for the image content and the semantics of the labels. The proposed framework combines a structure loss and a semantic adversarial loss in a multi-task objective function to train a fully convolutional neural network. The structure loss helps generate perturbations whose type and magnitude are defined by a target image processing filter. The semantic adversarial loss considers groups of (semantic) labels to craft perturbations that prevent the filtered image from being classified with a label in the same group. We validate our framework with three different target filters, namely detail enhancement, log transformation and gamma correction filters; and evaluate the adversarially filtered images against three classifiers, ResNet50, ResNet18 and AlexNet, pre-trained on ImageNet. We show that the proposed framework generates filtered images with a high success rate, robustness, and transferability to unseen classifiers. We also discuss objective and subjective evaluations of the adversarial perturbations.

15.
Artigo em Inglês | MEDLINE | ID: mdl-33769931

RESUMO

An effective person re-identification (re-ID) model should learn feature representations that are both discriminative, for distinguishing similar-looking people, and generalisable, for deployment across datasets without any adaptation. In this paper, we develop novel CNN architectures to address both challenges. First, we present a re-ID CNN termed omni-scale network (OSNet) to learn features that not only capture different spatial scales but also encapsulate a synergistic combination of multiple scales, namely omni-scale features. The basic building block consists of multiple convolutional streams, each detecting features at a certain scale. For omni-scale feature learning, a unified aggregation gate is introduced to dynamically fuse multi-scale features with channel-wise weights. OSNet is lightweight as its building blocks comprise factorised convolutions. Second, to improve generalisable feature learning, we introduce instance normalisation (IN) layers into OSNet to cope with cross-dataset discrepancies. Further, to determine the optimal placements of these IN layers in the architecture, we formulate an efficient differentiable architecture search algorithm. Extensive experiments show that, in the conventional same-dataset setting, OSNet achieves state-of-the-art performance, despite being much smaller than existing re-ID models. In the more challenging yet practical cross-dataset setting, OSNet beats most recent unsupervised domain adaptation methods without using any target data.

16.
Gastroenterol Rep (Oxf) ; 9(3): 234-240, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34316373

RESUMO

BACKGROUND: The prognosis of colorectal cancer depends on the number of positive lymph nodes (LN+) and the total number of lymph nodes resected (rLN). This represents the lymph-node ratio (LNR). The aim of our study is to assess how the length of the resected specimen (RL) influences the prognostic values of the LNR. METHODS: We conducted a retrospective study of all the patients operated on for colorectal cancer from 2000 to 2015 at our institution. Pathology details were analysed. The total number of rLN, the number of LN+, and the LNR were calculated and measured against the RL. The receiver-operating characteristic (ROC) curve of patients with LN+ was calculated. RESULTS: Of the 670 patients included in our study, 337 were men (50.3%) and the mean age was 69.2 years. The correlation with prognosis of the LNR is greater than that of the LNR adjusted to RL (LNR/RL), both in subjects with positive nodes (n = 312) and in all cases (n = 670). The LNR presents a higher prognostic value than LNR/RL and RL in patients with LN+ except for metastatic recurrence, for which the predictive value appears slightly higher for LNR/RL. The statistical significance of the maximal divergence in Kaplan-Meier survival plots was demonstrated for the LNR (P = 0.043), not for LNR/RL (P = 0.373) and RL alone (P = 0.314). CONCLUSION: An increase in RL causes an increase in the number of harvested lymph nodes without affecting the number of LN+, thus representing a confounding factor that could alter the prognostic value of the LNR. Prospective larger-scale studies are needed to confirm these findings.

17.
Adv Mater ; 33(48): e2105622, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34611954

RESUMO

Tuning oxygen mass transport properties at the nanoscale offers a promising approach for developing high performing energy materials. A number of strategies for engineering interfaces with enhanced oxygen diffusivity and surface exchange have been proposed. However, the origin and the magnitude of such local effects remain largely undisclosed to date due to the lack of direct measurement tools with sufficient resolution. In this work, atom probe tomography with sub-nanometer resolution is used to study oxygen mass transport on oxygen-isotope exchanged thin films of lanthanum chromite. A direct 3D visualization of nanoscaled highly conducting oxygen incorporation pathways along grain boundaries, with reliable quantification of the oxygen kinetic parameters and correlative link to local chemistries, is presented. Combined with finite element simulations of the exact nanostructure, isotope exchange-atom probe tomography allowed quantifying an enhancement in the grain boundary oxygen diffusivity and in the surface exchange coefficient of lanthanum chromite of about 4 and 3 orders of magnitude, respectively, compared to the bulk. This remarkable increase of the oxygen kinetics in an interface-dominated material is unambiguously attributed to grain boundary conduction highways thanks to the use of a powerful technique that can be straightforwardly extended to the study of currently inaccessible multiple nanoscale mass transport phenomena.

18.
J Nanosci Nanotechnol ; 10(2): 1327-37, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20352795

RESUMO

The present study is devoted to analyze the compatibility of yttria-stabilized zirconia thin films prepared by pulsed laser deposition and metalorganic chemical vapor deposition techniques, with microfabrication processes based on silicon technologies for micro solid oxide fuel cells applications. Deposition of yttria-stabilized zirconia on Si/SiO2/Si3N4 substrates was optimized for both techniques in order to obtain high density and homogeneity, as well as a good crystallinity for film thicknesses ranging from 60 to 240 nm. In addition, stabilized zirconia free-standing membranes were fabricated from the deposited films with surface areas between 50 x 50 microm2 and 820 x 820 microm2. Particular emphasis was made on the analysis of the effect of the nature of the deposition technique and the different design and fabrication parameters (membrane area, thickness and substrate deposition temperature) on the residual stress of the membranes in order to control their thermomechanical stability for application as electrolyte in micro solid oxide fuel cells.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31944973

RESUMO

Binary descriptors are widely used for multi-view matching and robotic navigation. However, their matching performance decreases considerably under severe scale and viewpoint changes in non-planar scenes. To overcome this problem, we propose to encode the varying appearance of selected 3D scene points tracked by a moving camera with compact spatio-temporal descriptors. To this end, we first track interest points and capture their temporal variations at multiple scales. Then, we validate feature tracks through 3D reconstruction and compress the temporal sequence of descriptors by encoding the most frequent and stable binary values. Finally, we determine multiscale correspondences across views with a matching strategy that handles severe scale differences. The proposed spatio-temporal multi-scale approach is generic and can be used with a variety of binary descriptors. We show the effectiveness of the joint multiscale extraction and temporal reduction through comparisons of different temporal reduction strategies and the application to several binary descriptors.

20.
PLoS One ; 15(4): e0232429, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348353

RESUMO

The use of endoscopic techniques to cure small sized, well differentiated early gastric cancer has been adopted worldwide. In the Eastern world, endoscopic resection is being increasingly utilized to treat small undifferentiated early gastric cancer according to the extended criteria proposed by the Japanese Gastric Cancer Associations. However, studies in the Western world reported in these tumors a rate of nodal metastasis ranging between 5% and 20%, that is higher of those observed in Eastern counterparts. A tool to predict the risk of nodal dissemination would be of great use to guide treatment toward endoscopic resection. In our study, we propose E-cadherin expression as a biological factor to predict lymph node involvement. We retrospectively reviewed the E-cadherin (E-cad) expression profile of all histological specimens of undifferentiated early gastric cancer from two Oncologic Departments and compared it with several tumor characteristics. A total of 39 patients with early gastric cancer met the inclusion criteria, of which 16 (41%) pT1a, and 23 (58.9%) pT1b SM1. Thirty-two patients (82%) underwent subtotal gastrectomy, whereas total gastrectomy was performed in only seven cases (17.9%). Patients were divided into two groups: low E-cad expression (E-cad 0/1+, 10 patients) and high E-cad expression (E-cad 2+/3+, 29 patients) according to the immunohistochemical assay (ICH). On univariate analysis, we found an association between low E-cad expression and low grading tumor (p = 0.019), pure undifferentiated histotype (PU-type) (p = 0.014), and lymph node involvement (N+) (p < 0.001). The association between low E-cad expression and lymph node metastasis was confirmed by multivariate analysis (OR = 14.5, 95% CI 3.46-60.76, p < 0.001). The loss of expression of E-cad may be a simple biological factor to predict lymph nodes metastasis in patients with undifferentiated early gastric cancer. Additional larger prospective studies are necessary to confirm these findings.


Assuntos
Caderinas/análise , Metástase Linfática/patologia , Neoplasias Gástricas/patologia , Idoso , Feminino , Humanos , Metástase Linfática/diagnóstico , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/diagnóstico
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