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1.
Chirurgia (Bucur) ; 117(1): 110-113, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35272761

RESUMEN

The magnification of images provided by minimally-invasive surgery (MIS) allows a very sharp and precise dissection of the hepatic hilum, allowing to overcome the technical complexity of surgery of perihilar cholangiocarcinoma (PHC). Recently, the feasibility and reproducibility of MIS for PHC are reported: within centers with adequate expertise and respecting the cornerstones of oncological adequacy, it provides short term advantages in a selected population of patients. The video reports the case of a patient with PHC involving the right biliary duct and requiring right hepatectomy with biliary confluence and segment 1 resection, with associated lymphadenectomy. Current evidences, together with feasibility and reproducibility of the technique shown in this video, appear promising and constitute a good prerequisite for the further implementation of this approach to improve patients outcome while following the principles of surgical oncology in hilar cholangiocarcinoma.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Tumor de Klatskin , Neoplasias de los Conductos Biliares/diagnóstico por imagen , Neoplasias de los Conductos Biliares/cirugía , Conductos Biliares Intrahepáticos/cirugía , Colangiocarcinoma/diagnóstico por imagen , Colangiocarcinoma/cirugía , Hepatectomía/métodos , Humanos , Tumor de Klatskin/cirugía , Reproducibilidad de los Resultados , Resultado del Tratamiento
2.
Chirurgia (Bucur) ; 2021-November: 1-4, 2021 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-34915690

RESUMEN

The magnification of images provided by minimally-invasive surgery (MIS) allows a very sharp and precise dissection of the hepatic hilum, allowing to overcome the technical complexity of surgery of perihilar cholangiocarcinoma (PHC). Recently, the feasibility and reproducibility of MIS for PHC are reported: within centers with adequate expertise and respecting the cornerstones of oncological adequacy, it provides short term advantages in a selected population of patients. The video reports the case of a patient with PHC involving the right biliary duct and requiring right hepatectomy with biliary confluence and segment 1 resection, with associated lymphadenectomy. Current evidences, together with feasibility and reproducibility of the technique shown in this video, appear promising and constitute a good prerequisite for the further implementation of this approach to improve patients outcome while following the principles of surgical oncology in hilar cholangiocarcinoma.

3.
Ultramicroscopy ; 102(2): 161-71, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15590139

RESUMEN

The wear of an atomic force microscope (AFM) tip is one of the crucial issues in AFM as well as in other probe-based applications. In this work, wear tests under extremely low normal load using an AFM were conducted. Also, in order to understand the nature of silicon tip wear, the wear characteristics of crystal silicon and amorphous silicon oxide layer were investigated by a high-resolution transmission electron microscope (HRTEM). It was found that fracture of the tip readily occurred due to impact during the approach process. Experimental results showed that the impact should be below 0.1 nNs to avoid significant fracture of the tip. Also, it was observed that wear of the amorphous layer, formed at the end of the tip, occurred at the initial stage of the silicon tip damage process. Based on Archard's wear law, the wear coefficient of the amorphous layer was in the range of 0.009-0.014. As for the wear characteristics of the silicon tip, it was shown that wear occurred gradually under light normal load and the wear rate decreased with increase in the sliding distance. As for the wear mechanism of the silicon tip, oxidation wear was identified to be the most significant. It was shown that the degree of oxidation was higher under high normal load and in a nitrogen environment, oxidation of the silicon tip was reduced.


Asunto(s)
Microscopía de Fuerza Atómica/instrumentación , Silicio/química , Microscopía Electrónica de Transmisión , Estrés Mecánico , Propiedades de Superficie
4.
Radiat Oncol J ; 33(3): 242-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26484308

RESUMEN

PURPOSE: The purpose of this study is to compare the dosimetry of electron beam (EB) plans and three-dimensional helical tomotherapy (3DHT) plans for the patients with left-sided breast cancer, who underwent breast conserving surgery. MATERIALS AND METHODS: We selected total of 15 patients based on the location of tumor, as following subsite: subareolar, upper outer, upper inner, lower lateral, and lower medial quadrants. The clinical target volume (CTV) was defined as the area of architectural distortion surrounded by surgical clip plus 1 cm margin. The conformity index (CI), homogeneity index (HI), quality of coverage (QC) and dose-volume parameters for the CTV, and organ at risk (OAR) were calculated. The following treatment techniques were assessed: single conformal EB plans; 3DHT plans with directional block of left anterior descending artery (LAD); and 3DHT plans with complete block of LAD. RESULTS: 3DHT plans, regardless of type of LAD block, showed significantly better CI, HI, and QC for the CTVs, compared with the EB plans. However, 3DHT plans showed increase in the V1Gy at skin, left lung, and left breast. In terms of LAD, 3DHT plans with complete block of LAD showed extremely low dose, while dose increase in other OARs were observed, when compared with other plans. EB plans showed the worst conformity at upper outer quadrants of tumor bed site. CONCLUSION: 3DHT plans offer more favorable dose distributions to LAD, as well as improved target coverage in comparison with EB plans.

5.
Brain Res ; 965(1-2): 130-6, 2003 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-12591129

RESUMEN

The flavonoids quercetin, (+)-dihydroquercetin, and quercetin 3-methyl ether were isolated from the ethyl acetate fractions of the fruits and stems of Opuntia ficus-indica var. saboten. In the present study, we evaluated their protective effects against oxidative neuronal injuries induced in primary cultured rat cortical cells and their antioxidant activities by using three different cell-free bioassays. Quercetin was found to inhibit H(2)O(2)- or xanthine (X)/xanthine oxidase (XO)-induced oxidative neuronal cell injury, with an estimated IC(50) of 4-5 micro g/ml. However, it was no more protective at concentrations of 30 micro g/ml and above. (+)-Dihydroquercetin concentration-dependently inhibited oxidative neuronal injuries, but it was less potent than quercetin. On the other hand, quercetin 3-methyl ether potently and dramatically inhibited H(2)O(2)- and X/XO-induced neuronal injuries, with IC(50) values of 0.6 and 0.7 micro g/ml, respectively. All three principles markedly inhibited lipid peroxidation and scavenged 1,1-diphenyl-2-picrylhydrazyl free radicals. In addition, quercetin and quercetin 3-methyl ether were shown to inhibit XO activity in vitro, with respective IC(50) values of 10.67 and 42.01 micro g/ml. These results indicate that quercetin, (+)-dihydroquercetin, and quercetin 3-methyl ether are the active antioxidant principles in the fruits and stems of Opuntia ficus-indica var. saboten exhibiting neuroprotective actions against the oxidative injuries induced in cortical cell cultures. Furthermore, quercetin 3-methyl ether appears to be the most potent neuroprotectant of the three flavonoids isolated from this plant.


Asunto(s)
Antioxidantes/farmacología , Flavonoides/farmacología , Fármacos Neuroprotectores/farmacología , Opuntia , Quercetina/análogos & derivados , Quercetina/farmacología , Animales , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Células Cultivadas , Corteza Cerebral/citología , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Relación Dosis-Respuesta a Droga , Embrión de Mamíferos , Flavonoides/química , Flavonoides/aislamiento & purificación , Flavonoles , Frutas/química , Peroxidación de Lípido/efectos de los fármacos , Peroxidación de Lípido/fisiología , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/aislamiento & purificación , Opuntia/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Tallos de la Planta/química , Quercetina/química , Quercetina/aislamiento & purificación , Ratas , Ratas Sprague-Dawley
6.
Eur J Pharmacol ; 495(2-3): 201-8, 2004 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-15249171

RESUMEN

Genipin, the aglycone of geniposide, is metabolically produced from the geniposide in body tissues. The purpose of this study is to clarify some pharmacological actions of genipin. Genipin showed concentration-dependent inhibition on lipid peroxidation induced by Fe++/ascorbate in rat brain homogenate. Genipin exhibited significant topical antiinflammatory effect shown as an inhibition of croton oil-induced ear edema in mice. Nitric oxide (NO) synthesis by inducible nitric oxide synthase (iNOS) is increased in inflammatory diseases and leads to cellular injury. Genipin concentration-dependently (50-300 microM) inhibited NO production and iNOS expression upon stimulation by lipopolysaccharide/interferon-gamma (IFN-gamma) in RAW 264.7, a murine macrophage cell line. Genipin markedly blocked lipopolysaccharide-evoked degradation of inhibitor-kappaB-beta (IkappaB-beta), indicating that it exhibits inhibitory effect on NO production through the inhibition of nuclear factor-kappaB (NF-kappaB) activation. It was also shown to contain potent antiangiogenic activity in a dose-dependent manner, which was detected by chick embryo chorioallantoic membrane assay. In summary, we demonstrate that genipin possesses antiinflammatory and is a specific hydroxyl radical scavenger. Its antiangiogenic and NO production-inhibitory properties are also presented.


Asunto(s)
Antiinflamatorios/farmacología , Gardenia/química , Piranos/farmacología , Inhibidores de la Angiogénesis/farmacología , Animales , Antioxidantes/farmacología , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Membrana Corioalantoides/irrigación sanguínea , Membrana Corioalantoides/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Oído/patología , Edema/prevención & control , Femenino , Immunoblotting , Interferón gamma/farmacología , Glicósidos Iridoides , Iridoides , Peroxidación de Lípido/efectos de los fármacos , Lipopolisacáridos/farmacología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa/biosíntesis , Óxido Nítrico Sintasa de Tipo II , Ratas , Ratas Sprague-Dawley
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