Charge-polarized interfacial superlattices in marginally twisted hexagonal boron nitride.

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.

Sizing single nanoscale objects from polarization forces.

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.

Anomalously low dielectric constant of confined water.

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.

Nanoscale dielectric microscopy of non-planar samples by lift-mode electrostatic force microscopy.

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.

Biological and pathological features in pregnancy-associated breast cancer: a matched case-control study.

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.

Impact of Surgery on the Evolution of Uterine Sarcomas.

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.

Hormone receptor and HER2 status: The only predictive factors of response to neoadjuvant chemotherapy in breast cancer.

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.

Infección mamaria por Salmonella en paciente portadora de prótesis / No disponible

La infección mamaria por Salmonella es una entidad sumamente infrecuente. Una correcta anamnesis y exploración, así como las pruebas complementarias donde la ecografía mamaria juega un papel esencial, son necesarias para establecer un diagnóstico preciso. Presentamos el caso de una infección mamaria por Salmonella en una paciente portadora de prótesis mamaria con antecedentes de un viaje a una zona desfavorecida en Thailandia(AU)

Mammary infection with Salmonella is a very rare entity. A proper history and examination, and where additional tests breast ultrasound plays an essential role, are needed to establish an accurate diagnosis. We present the case of a breast infection by Salmonella in a patient with breast implant with a history of travel in a disadvantaged area in Thailand(AU)

Conservative treatment by endoscopy of a cesarean scar pregnancy: two case reports.

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.

Hiperplasia intraductal atípica o carcinoma intraductal grado 1 vs. DIN1c / No disponible

Objetivo: La clasificación DIN incluye en el DIN1c la hiperplasiaintraductal atípica (HIA) y el carcinoma intraductal grado1 (CID1). El objetivo de este estudio es ver si esta agrupacióndiagnóstica, con las consecuencias terapéuticas que elloconlleva, implica o no un sobretratamiento de la HIA.Pacientes y métodos: Se ha revisado el tratamiento y laevolución de los casos de HIA y CID1 diagnosticados en nuestrocentro desde 1999 hasta 2008. Se han utilizado los mismoscriterios diagnósticos que utiliza la clasificación DIN paradiferenciar la HIA y el CID1.Resultados: De 117 casos, 49 fueron HIA y 68 CID1. Eltratamiento quirúrgico fue tumorectomía, independientementedel estado del margen, en 47 (96%) HIA y en 53 (78%) CID1consiguiendo siempre un margen libre. En 42 (62%) casos deCID1 el tratamiento se complementó con radioterapia. Uncaso de HIA y otro de CID1 recidivaron tras 24 y 39 mesesen forma de carcinoma ductal infiltrante.Conclusiones: La clasificación DIN simplifica el diagnóstico,no obstante agrupar alguna de estas lesiones puede conllevarsu sobretratamiento. En nuestra serie la simple extirpaciónde una HIA independientemente del estado del margen hasido curativa en la mayoría de casos(AU)

Objective: DIN classification includes into DIN1c the atypicalintraductal hyperplasia (AIH) and intraductal carcinomagrade 1 (IDC1). The aim of this study is to see if this grouping,with its therapeuthical consequences, implies an overtreatmentof AIH.Patients and methods: Treatment and follow-up of allthose cases diagnosed of AIH and IDC1 between 1999 and2008 at our centre have been revised. The diagnostic criteriato differentiate AIH and IDC1 were the same used in DIN classification.Results: Of the 117 studied cases, 49 were diagnosed asAIH and 68 as IDC1. Lumpectomy, independently of the statusof the margin was performed in 47 (96%) AIH, and 53(78%) IDC1 with adequate resection margin. In 42 (62%) casesof IDC1 adjuvant radiotherapy was given. One case of AIHand one case of IDC1 recurred as invasive ductal carcinoma,24 and 39 months later respectively.Conclusions: DIN classification simplifies the diagnosis butgrouping these lesions can result into an overtreatment. In ourserie the surgical excision of AIH independently of the statusof the margin was curative in the majority of the cases(AU)

Neurofibroma of the vaginal wall.

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.

Carcinoma oculto de la mama metastásico en ganglio intramamario / No disponible

Se presenta un caso de una mujer de 63 años con un nóduloen los cuadrantes externos de la mama derecha con característicasmamográficas y ecográficas de benignidad, en la queel estudio citológico evidencia un carcinoma, el cual histológicamentecorresponde a un ganglio linfático intramamario metastásicocon un primario en la glándula mamaria no detectado

A case of a 63-year old woman with a nodular lesion in theexternal quadrants of the right breast. The lesion was mammographicallyand ultrasonographically benign, but fine needleaspiration showed a carcinoma. Pathologic examinationrevealed a metastatic intramammary lymph node, but the primarycarcinoma in the breast could not be detected

Carcinoma micropapilar infiltrante de la mama y biopsia del ganglio centinela / Infiltrating micropapillary carcinoma of the breast and sentinel lymph node biopsy

Objetivo: Las características histopatológicas del tumorpueden hacer que no sea posible la práctica de la biopsia delganglio centinela (BGC). El propósito de este estudio es evaluarla aplicación y los resultados de esta técnica en pacientescon carcinoma micropapilar infiltrante (CMI) de la mama.Pacientes y método: Durante los últimos siete años ennuestro centro se ha efectuado la BGC en 294 pacientes y sehan diagnosticado 37 CMI. Se trata de un estudio retrospectivode la técnica utilizada para la estadificación ganglionar enestas pacientes. Los resultados de la BGC en pacientes conCMI se comparan con los resultados de esta técnica en pacientescon otros tipos histológicos de cáncer de mama.Resultados: La BGC sólo pudo efectuarse en 8 (22%) delas pacientes con CMI. Cuatro presentaron metástasis, unamicrometástasis y dos células tumorales aisladas (CTA). Ensólo una de las pacientes se detectaron más ganglios afectadosen el resto de la linfadenectomía. En aquellas pacientes en lasque no se pudo realizar la BGC, las principales contraindicacionesfueron: el diagnóstico prequirúrgico de afectación ganglionarmediante punción aspiración con aguja fina guiadaecográficamente y la multifocalidad.Conclusiones: La BGC puede realizarse en pocas ocasionesen pacientes con CMI. Cuando esta puede efectuarse, elporcentaje de metástasis es alto aunque con frecuencia el centinelaes el único ganglio afectado

Objective: Hystopatologic tumor characteristics can carryfailure in the practice of sentinel lymph node (SLN) biopsy.The aim of this study is to evaluate the application and the resultsof this technique in patients with infiltrating micropapillarycarcinoma (IMPC) of the breast.Patients and method: During the last seven years in ourcenter SLN biopsy has been performed in 294 patients and37 IMPC have been diagnosed. This is a retrospective study ofthe technique used for nodal staging in these patients. The resultsof SLN biopsy in those patients with IMPC were comparedwith the results of this technique in patients with other histologicaltypes of breast cancer.Results: SLN biopsy could be done in only 8 (22%) patientswith IMPC. Four had metastases, one micrometastasisand two isolated tumor cells. Only one patient showed morelymph nodes involved in the axilla. In those patients in whomthe SLN biopsy could not be done, positive fine needle aspirationunder ulltrasonographic guidance and multifocal breast involvementwere the main contraindications.Conclusions: SLN biopsy is infrequently indicated in thosepatients with IMPC and, when performed, the percentageof lymph node metastasis is high but mostly limited to SLN

Condrolipoma de la mama detectado por microcalcificaciones mamográficas / Chondrolipoma of the breast detected by microcalcifications on mammography

Se presenta el caso de una paciente de 50 años de edad, con unas microcalcificaciones mamográficas de nueva aparición y sospechosas de malignidad. La lesión se extirpó quirúrgicamente y el examen microscópico evidenció una lesión constituida por islotes maduros de tejido adiposo y cartilaginoso con focos de calcificación y osificación. El condrolipoma es un tumor benigno del que hay pocos casos descritos en la bibliografía. Se presentan los aspectos clínicos e histológicos y se discuten los diagnósticos diferenciales y la etiopatogenia del tumor

The case of a 50-year-old woman with recently developed microcalcifications on mammogram which were suspicious for malignancy is presented. The lesion was surgically removed and histological examination revealed islands of mature adipose and cartilaginous tissues with calcifications and focal ossification. Chondrolipoma is a benign tumor and only a few cases have been reported in the literature. The clinical and histological features are described, and the differential diagnosis and etiopathogenesis are discussed

Endometrial cancer: factors affecting survival.

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.

Histerectomía laparoscópica frente a no laparoscópica / Laparoscopic versus non-laparoscopic hysterectomy

Objetivo: Mostrar la evolución en nuestro servicio de las indicaciones y vías de abordaje de la histerectomía. Material y métodos: Se estudian los datos obtenidos de 418 pacientes sometidas a histerectomía en el período 1994-1998. Se comparan las indicaciones, la edad, el peso y la talla de las pacientes y las características de las piezas obtenidas. Resultados: La edad de las pacientes de nuestro estudio fue de 49,9 años (28-93), con una talla media de 159 cm (141-174) y un peso de 61,6 kg (42-92). Las indicaciones para la histerectomía abdominal han sido: fibromiomatosis (51,3 per cent), procesos neoplásicos (31 per cent) y prolapsos uterinos (1,3 per cent). En el caso de la histerectomía vaginal las indicaciones han sido: prolapso uterino (70,8 per cent), mioma uterino (18,58 per cent) y neoplasia (1,77 per cent). Las indicaciones para la histerectectomía vaginal laparoscópicamente asistida (HVLA) han sido: fibromatosis (37 per cent), prolapso (13,7 per cent), neoplasia (9,59 per cent), endometriosis el (9,6 per cent) y enfermedades anexiales asociadas (12,3 per cent). Se encontraron diferencias estadísticamente significativas entre los grupos para la edad y el peso de las pacientes. También se encontraron diferencias en el peso, el tamaño y el volumen de las muestras. La morbilidad durante este período que ha requerido de cirugía complementaria ha sido de un 4,7 per cent para la histerectomía abdominal, de un 5,5 per cent para la cirugía vaginal y de un 2,3 per cent para la HVLA. Conclusiones: En los últimos años hemos reducido el número global de histerectomías gracias a diferentes alternativas terapéuticas, observando un incremento progresivo de la técnica vaginal (pura o laparoscópica) frente a la abdominal (AU)

Tuberculosis peritoneal. Descripción de un caso / Peritoneal tuberculosis. Report of a case

Debemos pensar en el diagnóstico de tuberculosis peritoneal en cualquier paciente con dolor abdominal de etiología desconocida, ascitis y fiebre. Puede presentarse de manera insidiosa (forma clásica), o bien como infertilidad primaria o secundaria (forma actual). El diagnóstico se realiza con el estudio anatomopatológico de los granulomas caseificantes y mediante el cultivo del líquido peritoneal. Nuevas pruebas diagnósticas, como el estudio del ADA (ascitis fluid adenosine deaminasa), pueden cambiar el algoritmo diagnóstico de esta enfermedad (AU)

Fibroadenoma y cáncer de mama: aspectos clinicopatológicos en 8 casos / Fibroadenoma and breast cancer: clinicopathologic features in eight cases

Objetivo: Revisar los hallazgos clinicopatológicos de los fibroadenomas afectados por un carcinoma de la mama. Pacientes y método: Se han observado 8 casos en los que existía infiltración de un fibroadenoma por un carcinoma durante un período de 11 años. Se revisan los aspectos clinicopatológicos de estos tumores, así como el de las lesiones asociadas en el parénquima circundante. Resultados: Cuatro de los casos presentaron lesiones in situ (dos ductales y dos lobulillares), identificándose en tres de ellos la presencia de neoplasia en el parénquima mamario circundante. En los otros 4 casos la lesión era infiltrante (dos ductales y dos lobulillares) y en todos ellos se extendía más allá del fibroadenoma. Conclusión: La asociación de carcinoma y fibroadenoma es poco frecuente y, en estos casos, tanto el tratamiento como el pronóstico están en función de las características propias del tumor que infiltra al fibroadenoma. (AU)

Detección de micrometástasis en el ganglio centinela de pacientes con cáncer infiltrante de mama / Detection of micrometastases in the sentinel node of patients with infiltrating breast cancer

Objetivo: La afección de los ganglios linfáticos es el factor pronóstico más importante en las pacientes con cáncer de la mama. El examen del ganglio centinela es una alternativa al estudio completo de la axila.Material y métodos: Se han estudiado 164 ganglios centinela en 100 pacientes con cáncer de mama. Se utilizó un protocolo estándar para el estudio de 21 láminas (cuatro de ellas teñidas con inmunohistoquímica). Se relacionó el número de láminas estudiadas con la positividad o no de los ganglios, y en el primer caso con el tipo de afección. También se tuvo en cuenta el tamaño del tumor y el estado del resto de la linfadenectomía.Resultados: Un total de 52 ganglios centinela fue positivo, 17 de ellos evidenciaron metástasis, 19 micrometástasis y 16 células tumorales aisladas.Todas las metástasis se diagnosticaron en la primera lámina estudiada teñida con hematoxilinaeosina; sin embargo, para el diagnóstico de todas las micrometástasis y de las células tumorales aisladas se precisaron 16 y 19 láminas, respectivamente (cuatro de ellas teñidas con inmunohistoquímica).Conclusión: Para el diagnóstico de micrometástasis y de células tumorales aisladas se precisa un protocolo que incluya múltiples secciones y técnicas de inmunohistoquímica (AU)