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1.
Nanotechnology ; 27(40): 405706, 2016 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-27597315

RESUMEN

Lift-mode electrostatic force microscopy (EFM) is one of the most convenient imaging modes to study the local dielectric properties of non-planar samples. Here we present the quantitative analysis of this imaging mode. We introduce a method to quantify and subtract the topographic crosstalk from the lift-mode EFM images, and a 3D numerical approach that allows for extracting the local dielectric constant with nanoscale spatial resolution free from topographic artifacts. We demonstrate this procedure by measuring the dielectric properties of micropatterned SiO2 pillars and of single bacteria cells, thus illustrating the wide applicability of our approach from materials science to biology.

2.
J Minim Invasive Gynecol ; 22(6): 1068-74, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26070730

RESUMEN

STUDY OBJECTIVE: To identify the characteristics of uterine sarcomas and assess the impact of morcellation on prognosis. DESIGN: Case-control study. (Canadian Task Force classification II-2). SETTING: Hospital Quiron-Dexeus, an academic hospital. PATIENTS: Patients with uterine sarcoma histologically diagnosed and treated in our center between 1987 and 2013. INTERVENTION: All descriptive data, including type of surgery and clinical and pathological data, were reviewed. Survival analysis was performed comparing patients with hysterectomy/myomectomy without any type of morcellation and patients with morcellation during surgery. MEASUREMENTS AND MAIN RESULTS: A total of 37 sarcomas were diagnosed during the study period. The most common symptom was metrorrhagia (50%). The indication for surgery was related to myoma growth in 40% of cases and to metrorrhagia in 37.1% of cases. Open surgery was performed in 23 patients (62.2%), and laparoscopy was performed in 9 (24.3%). Myomectomy was performed in 14 patients (37.8%), and 23 patients (62.1%) underwent hysterectomy as initial surgery. Morcellation for tumor extraction was done in 8 cases (21.6%). Survival analysis by surgical approach showed increased disease-free survival (DFS) in the laparotomy group compared with the laparoscopy group (median, 70.3 months vs 10.4 months; p = .018). Median DFS according to type of surgery was 6.3 months in morcellation cases, 11.9 months in vaginal fragmentation cases, and 149.9 months in nonmorcellated cases (p < .002). The median time to progression was shorter in morcellated cases (laparocopic and vaginal) compared with nonmorcellated cases (11.9 vs 14.9 months; p < .001). No statistically significant differences in prognosis were related to myomectomy versus hysterectomy; however, there were significants difference between morcellation and nonmorcellation cases. CONCLUSION: Taking into account the negative impact of morcellation in sarcomas, the use of this technique should be reconsidered in cases of myoma with atypical clinical presentation or symptomatology. Patients must be informed about the possibility of a nonidentified sarcoma and the possible impact on prognosis resulting from its morcellation.


Asunto(s)
Histerectomía , Laparoscopía , Laparotomía , Metrorragia/cirugía , Sarcoma/cirugía , Miomectomía Uterina , Neoplasias Uterinas/cirugía , Adulto , Anciano , Estudios de Casos y Controles , Supervivencia sin Enfermedad , Femenino , Humanos , Histerectomía/métodos , Laparoscopía/métodos , Laparotomía/métodos , Metrorragia/patología , Persona de Mediana Edad , Pronóstico , Sarcoma/patología , Análisis de Supervivencia , Miomectomía Uterina/métodos , Neoplasias Uterinas/patología
3.
Eur J Gynaecol Oncol ; 36(4): 420-3, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26390695

RESUMEN

BACKGROUND: The prognosis for breast cancer has been considered to be worsened by the coexistence of pregnancy. However, to date, significant controversy still exists regarding the pathological tumor features and prognosis of patients diagnosed with pregnancy-associated breast cancer (PABC). The aim of the present study was to analyze the different prognostic factors and outcome in PABC subset versus a non-PABC control group matched for age and year of diagnosis. MATERIALS AND METHODS: A total of 56 PABC cases were diagnosed from 1990 to 2008, for whom 73 non-PABC patients were identified. Pathological characteristics, immunohistochemical fea- tures, and differences in overall and disease-free survival were compared between both groups. RESULTS: Compared to non-PABC controls, PABC patients presented more advanced disease (31% vs 13%, p = 0.024) and greater lymph node involvement (53% vs 34%, p = 0.034). Pathological and tumor features tended to present poorer prognostic factors in the PABC subset. Survival was poorer in the PABC patients (five-year DFS 68% in PABC vs 86% in non-PABC, p = 0.12). However, analysing survival adjusted for stage and age, the authors did not find significant differences between both groups. CONCLUSIONS: PABC patients tended to be diagnosed in advanced breast disease and presented tumors with adverse pathological prognostic factors. While the authors found a poorer outcome in PABC group, no significant differences were observed with stage-matched analysis. The present results may suggest that the poorer prognosis observed within PABC women could not be due to pregnancy itself, but with a delay in diagnosis and tumor subtype pathological features.


Asunto(s)
Neoplasias de la Mama/patología , Complicaciones Neoplásicas del Embarazo/patología , Adulto , Neoplasias de la Mama/mortalidad , Estudios de Casos y Controles , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Complicaciones Neoplásicas del Embarazo/mortalidad , Pronóstico
4.
J Obstet Gynaecol ; 35(5): 485-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25383894

RESUMEN

We report our experience in neoadjuvant breast cancer chemotherapy in a single centre between 2000 and 2011. We looked for predictive factors for response to neoadjuvant chemotherapy in the present study. A total of 110 consecutive breast cancer patients were treated with neoadjuvant chemotherapy in our centre. Pathological response was achieved in 24 HR+/HER2- (38.7%), 25 HER2+ (67.6%) and five triple-negative (45.5%) (p = 0.02) patients. No statistically significant differences were found in pathological tumour response according to T stage. The multivariate analysis revealed tumour subtype was the only associated factor for pathological response, with HER2 + tumours the best responders, OR 3.9 (1.5-9.9): 5-year DFS was 40% HER2+/no response; 78% HER2+/response; 65% HR+/HER2-/no response; 82% HR+/HER2-/response; 25% triple-negative/no response and 100% triple-negative/response. HR and HER2 status were the only prognostic factors for pathological response. pCR was correlated with survival in all tumour subtypes.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Neoplasias de la Mama/metabolismo , Femenino , Humanos , Persona de Mediana Edad , Terapia Neoadyuvante , Estudios Retrospectivos , Resultado del Tratamiento
5.
Nat Commun ; 12(1): 347, 2021 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33436620

RESUMEN

When two-dimensional crystals are brought into close proximity, their interaction results in reconstruction of electronic spectrum and crystal structure. Such reconstruction strongly depends on the twist angle between the crystals, which has received growing attention due to interesting electronic and optical properties that arise in graphene and transitional metal dichalcogenides. Here we study two insulating crystals of hexagonal boron nitride stacked at small twist angle. Using electrostatic force microscopy, we observe ferroelectric-like domains arranged in triangular superlattices with a large surface potential. The observation is attributed to interfacial elastic deformations that result in out-of-plane dipoles formed by pairs of boron and nitrogen atoms belonging to opposite interfacial surfaces. This creates a bilayer-thick ferroelectric with oppositely polarized (BN and NB) dipoles in neighbouring domains, in agreement with our modeling. These findings open up possibilities for designing van der Waals heterostructures and offer an alternative probe to study moiré-superlattice electrostatic potentials.

6.
Clin Exp Obstet Gynecol ; 36(2): 126-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19688959

RESUMEN

BACKGROUND: Cesarean section scar pregnancy is the rarest form of ectopic pregnancy and the most dangerous due to the high risk of uterine rupture and hemorrhage. CASE: We present two case reports of women diagnosed with an ectopic cesarean scar pregnancy. We performed conservative treatment because both patients desired fertility preservation. The first case was treated with laparoscopy and hysteroscopy simultaneously. For the second case the treatment started with an ultrasound-guided injection of methotrexate. Surgical laparoscopy and hysteroscopy were subsequently performed simultaneously. Four months later, the first woman had a spontaneous singleton pregnancy. An elective cesarean was performed. CONCLUSION: In these two case reports we have presented our experience with endoscopic surgery in the management of two patients who had a cesarean scar pregnancy and desired to preserve their fertility.


Asunto(s)
Cesárea/efectos adversos , Cicatriz/cirugía , Histeroscopía/métodos , Embarazo Ectópico/cirugía , Dehiscencia de la Herida Operatoria/cirugía , Adulto , Cicatriz/complicaciones , Cicatriz/etiología , Endometrio/cirugía , Femenino , Humanos , Laparoscopía/métodos , Embarazo , Embarazo Ectópico/diagnóstico por imagen , Dehiscencia de la Herida Operatoria/complicaciones , Ultrasonografía
7.
Sci Rep ; 9(1): 14142, 2019 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-31578402

RESUMEN

Sizing natural or engineered single nanoscale objects is fundamental in many areas of science and technology. To achieve it several advanced microscopic techniques have been developed, mostly based on electron and scanning probe microscopies. Still for soft and poorly adhered samples the existing techniques face important challenges. Here, we propose an alternative method to size single nanoscale objects based on the measurement of its electric polarization. The method is based on Electrostatic Force Microscopy measurements combined with a specifically designed multiparameter quantification algorithm, which gives the physical dimensions (height and width) of the nanoscale object. The proposed method is validated with ~50 nm diameter silver nanowires, and successfully applied to ~10 nm diameter bacterial polar flagella, an example of soft and poorly adhered nanoscale object. We show that an accuracy comparable to AFM topographic imaging can be achieved. The main advantage of the proposed method is that, being based on the measurement of long-range polarization forces, it can be applied without contacting the sample, what is key when considering poorly adhered and soft nanoscale objects. Potential applications of the proposed method to a wide range of nanoscale objects relevant in Material, Life Sciences and Nanomedicine is envisaged.

8.
Clin Exp Obstet Gynecol ; 35(2): 140-3, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18581771

RESUMEN

BACKGROUND: Von Recklinghausen's disease is characterized by cutaneous manifestations but it is a systemic disease which may affect the genitourinary tract. CASE: A 20-year-old woman with a history of type-1 neurofibromatosis attended our center due to a vaginal nodule. Surgical treatment consisted of an incisional biopsy of the nodule. The anatomopathological diagnosis was plexiform neurofibroma. CONCLUSION: Periodical check-ups are recommended in asymptomatic vaginal neurofibroma whereas its radical excision should be avoided as such surgery is highly aggressive.


Asunto(s)
Neurofibroma/diagnóstico , Neoplasias Vaginales/diagnóstico , Adulto , Femenino , Humanos , Neurofibroma/diagnóstico por imagen , Neurofibroma/cirugía , Ultrasonografía Doppler en Color , Neoplasias Vaginales/diagnóstico por imagen , Neoplasias Vaginales/cirugía
9.
Science ; 360(6395): 1339-1342, 2018 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-29930134

RESUMEN

The dielectric constant ε of interfacial water has been predicted to be smaller than that of bulk water (ε ≈ 80) because the rotational freedom of water dipoles is expected to decrease near surfaces, yet experimental evidence is lacking. We report local capacitance measurements for water confined between two atomically flat walls separated by various distances down to 1 nanometer. Our experiments reveal the presence of an interfacial layer with vanishingly small polarization such that its out-of-plane ε is only ~2. The electrically dead layer is found to be two to three molecules thick. These results provide much-needed feedback for theories describing water-mediated surface interactions and the behavior of interfacial water, and show a way to investigate the dielectric properties of other fluids and solids under extreme confinement.

10.
Chest ; 69(4): 565-8, 1976 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1261333

RESUMEN

A 64-year old man had a history of two myocardial infarctions recurrent episodes of paroxysmal ventricular tachycardia and hemoptysis. Cineangiocardiographic studies showed an anomalous vessel connecting the left coronary artery with a peripheral branch of the right pulmonary artery. Although several coronary obstructive lesions and abnormalities in the distribution of the circumflex branches were found, the anomaly apparently produced a real "pulmonary steal" and, thereby a worsening of the coronary insufficiency. We believe that this is the first reported case in the literature with such a coronary-pulmonary fistula. The angiographic findings are presented in detail, and the possible factors in the development of myocardial ischemia are discussed.


Asunto(s)
Anomalías de los Vasos Coronarios/diagnóstico por imagen , Arteria Pulmonar/anomalías , Cateterismo Cardíaco , Angiografía Coronaria , Anomalías de los Vasos Coronarios/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Arteria Pulmonar/diagnóstico por imagen
11.
J Am Soc Echocardiogr ; 12(12): 1073-9, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10588783

RESUMEN

OBJECTIVES: We sought to compare the feasibility and accuracy of peak treadmill exercise echocardiography versus postexercise echocardiography imaging. BACKGROUND: Although peak exercise echocardiography has been reported for both supine and orthostatic bicycle exercise and has shown higher sensitivity than postexercise imaging, acquiring images at peak exercise with treadmill has not been explored. METHODS: Peak and post-treadmill exercise echocardiography and coronary angiography were performed on 89 patients with known or suspected coronary artery disease. Positive exercise echocardiography was defined as necrosis or ischemic response. Positive coronary angiography was defined as >/=1 diseased vessels (>/=50% luminal narrowing). Images were analyzed in a blind manner by an expert observer. RESULTS: Postexercise images were acquired within 80 seconds after exercise (40 +/- 14). Mean heart rate (bpm) was 139 +/- 22 at peak versus 118 +/- 25 at postexercise imaging (P <.001). Interpretable peak and postexercise images were obtained for all 89 patients. Of the 72 classified as having positive exercise echocardiography, 23 had new regional wall motion abnormality at peak (21 with positive angiography), which resolved at postexercise imaging. Sensitivity was higher with peak than with postexercise imaging (94% vs 73%, P <.001). Specificity was similar (68% vs 79%), as was predictive positive value (92% vs 93%). Negative predictive value was again higher with peak imaging (76% vs 44%, P <.05). Total accuracy was higher with peak imaging (89% vs 74%, P <.05). CONCLUSIONS: Peak treadmill exercise echocardiography is technically feasible and has higher sensitivity and accuracy than post-treadmill exercise echocardiography. Therefore in the clinical setting peak exercise echocardiography should be performed to diagnose ischemia.


Asunto(s)
Enfermedad Coronaria/diagnóstico por imagen , Ecocardiografía/métodos , Ejercicio Físico , Angiografía Coronaria , Enfermedad Coronaria/fisiopatología , Diagnóstico Diferencial , Prueba de Esfuerzo , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Contracción Miocárdica , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Volumen Sistólico
12.
Breast ; 10(2): 149-54, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-14965576

RESUMEN

Duct endoscopy is a recent technique used for a direct view of the breast ductal system. The aim of this study is to determine any morphological changes in breast tissue attributable to low-pressure irrigation with saline solution that the technique requires. A total of 26 breast biopsies from patients who underwent ductal endoscopy before surgery were compared with 26 breast specimens from the retroareolar region. Breast specimens from duct endoscopy showed more frequent epithelial detachment (73%), epithelial loss (35%), periductal clefts (77%), stromal disaggregation (46%) and displacement of epithelial cells into the stroma (27%) than the control group in which epithelial detachment was seen in 4% of patients, periductal clefts in 15%, and stromal disaggregation in 15%. Epithelial loss and epithelial displacement where not seen in the control group. Although low-pressure fluid perfusion used for duct endoscopy induced morphological changes in breast tissue, these can easily be distinguished from malignancy, and are most likely to occur as the result of duct rupture.

13.
Eur J Gynaecol Oncol ; 24(5): 381-3, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14584650

RESUMEN

PURPOSE: To evaluate the influence in survival of clinical and pathological findings in patients with endometrial cancer. METHODS: In 152 women treated for endometrial cancer from 1982 to 1996, personal, obstetrical and oncological data, histology, grade, myometrial invasion, peritoneal cytology, FIGO stage and treatment were correlated with survival. RESULTS: Mean age was of 60.3 +/- 11.1 years old. Eight patients had a previous history of other neoplasms (seven of them gynecological). The mean clinical complaint was abnormal uterine bleeding. The most common histological type was endometrioid (84.9%), only 51 cases did not show myometrial invasion and 119 women were in Stage I at diagnosis. Peritoneal cytology was negative in 113 patients. Seven patients out of 85 in whom lymphadenectomy was performed showed metastasis. Seventeen of the patients died. The factors influencing survival were age, myometrial invasion and lymph node metastasis. CONCLUSION: Lack of myometrial invasion, absence of lymph node metastasis and age younger than 60 years seem to be the most significant predicting factors of survival.


Asunto(s)
Neoplasias Endometriales/mortalidad , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adenocarcinoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma/mortalidad , Carcinoma/patología , Carcinoma/terapia , Neoplasias Endometriales/patología , Neoplasias Endometriales/terapia , Femenino , Humanos , Metástasis Linfática , Persona de Mediana Edad , Factores de Riesgo , Tasa de Supervivencia
14.
Eur J Gynaecol Oncol ; 20(3): 205-8, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10410887

RESUMEN

INTRODUCTION: Invasive micropapillary carcinoma (IMC) is a histological variant of breast cancer with a poor prognosis. MATERIAL AND METHODS: Pathological findings of 15 cases of IMC are compared with those of 144 invasive duct carcinoma (IDC) and 10 invasive papillary carcinoma (IPC). RESULTS: Only 33% of cases were diagnosed in stage I. Mean tumor size was 2.3 cm. Nuclear grade 3 was found in 60% of cases, aneuploidy in 78%, and 92% had hormone receptors. Nine patients showed lymph node metastasis. Tumor size, nuclear grade, mitotic rate and lymph node involvement were higher in IMC when compared with IDC grade I and IPC, but not when compared with IDC grade II and III. Four cases of IMC (27%) recurred before two years. Recurrences and lymph node metastases showed the same architectural pattern as the primary tumor. DISCUSSION: IMC shows a high incidence of lymph node involvement and a high early recurrence rate.


Asunto(s)
Neoplasias de la Mama/patología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Ductal de Mama/patología , Femenino , Humanos , Metástasis Linfática , Persona de Mediana Edad
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