Three-dimensional culture model to study the biology of vacuolated notochordal cells from mouse nucleus pulposus explants.

Intervertebral disc degeneration (IDD) involves cellular changes in the nucleus pulposus (NP) characterised by a decline of the large vacuolated notochordal cells (vNCs) and a rise of smaller vacuole-free mature chondrocyte-like NP cells. An increasing number of studies demonstrate that notochordal cells (NCs) exert disease-modifying effects, establishing that NC-secreted factors are essential for the maintenance of a healthy intervertebral disc (IVD). However, understanding the role of the NCs is hampered by a restricted reserve of native cells and the lack of robust ex vivo cell model. A precise dissection enabled the isolation of NP cells from 4 d post-natal stage mouse spines and their culture into self-organised micromasses. The maintenance of cells' phenotypic characteristics was demonstrated by the presence of intracytoplasmic vacuoles and the immuno-colocalisation of the NC-markers (brachyury; SOX9) after 9 d of culture both in hypoxic and normoxic conditions. A significant increase of the size of the micromass was observed under hypoxia, consistent with a higher level of Ki-67+ immunostained proliferative cells. Furthermore, several proteins of interest for the study of vNCs phenotype (CD44; caveolin-1; aquaporin 2; patched-1) were successfully detected at the plasma membrane of NP-cells cultured in micromasses under hypoxic condition. IHC was performed on mouse IVD sections as control staining. An innovative 3D culture model of vNCs derived from mouse postnatal NP is proposed, allowing future ex vivo exploration of their basic biology and of the signalling pathways involved in IVD homeostasis that may be relevant for disc repair.

Cáncer de mama Her2-positivo: Terapias sistémicas actuales y experiencia local

El cáncer de mama (CM) es la primera causa de muerte por cáncer en mujeres tanto a nivel mundial como en Chile. Basados en características clínicas, histológicas y moleculares, múltiples estudios han identificado cuatro subtipos básicos de CM, los cuales están asociados a estrategias de tratamiento específicas y diferenciadas. El CM HER2-positivo representa un 15%-25% de todas las neoplasias mamarias y se caracteriza por su agresividad, recurrencia temprana y mayor tendencia a presentar compromiso del sistema nervioso central. En las últimas décadas, nuevas terapias dirigidas se han posicionado como el estándar de tratamiento y han cambiado la historia natural de esta enfermedad, transformándola en una enfermedad potencialmente curable incluso en etapas avanzadas. Esta revisión busca entregar un resumen de las bases biológicas de esta enfermedad. Por otro lado, dada la aparición de un creciente número de nuevas estrategias de manejo sistémico, nos proponemos revisar sus mecanismos de acción analizando reportes de datos clínicos publicados y la experiencia de nuestro grupo.

Breast cancer (BC) is the leading cause of cancer death for women both worldwide and in Chile. Based on clinical, histological, and molecular features, studies have identified four BC subtypes that correlate with treatment sensitivity. Human Epidermal growth factor Receptor type 2-positive (HER2+) BC represents 15%-25% of newly diagnosed breast neoplasms; HER2+ BC is characterized by its aggressive behavior, early recurrence, and higher risk of brain metastasis. In recent years, HER2-targeted therapies have become the mainstay of treatment and have redefined the natural history of this subtype, reducing relapse rates for early-stage patients and increasing survival in advanced-stage patients. Herein we review novel treatment strategies and their mechanisms of action, along with clinical and real-world data. We also provide a summary of currently available treatments for this subtype and our local experience regarding the management of this disease.

[An unusual cause of a decline in general health in a very old person]. / Une cause inhabituelle d'altération de l'état général chez une personne très âgée.

Humans are accidental intermediate hosts and a dead-end for the echinococcosis parasite. No cases of hydatid echinococcosis (hydatid cyst) have ever been described in a French-born very elderly person, who has never been out of France. We report the case of a 90-year-old man hospitalised following a decline in his general health and the discovery of a liver mass on the CT-scan. The abdominal palpation was painless, and no mass was felt. Biological tests revealed hypereosinophilia, a mild inflammatory syndrome, a slight increase in the immunoglobulin E level, and positive serology for Echinococcus granulosus. A diagnosis of hydatid echinococcosis due to Echinococcus granulosus was made given the liver mass on the CT-scan, the positive serology and the hypereosinophilia. Management consisted of watch and wait. This observation is interesting because it was a case of an autochthonous hydatid cyst of an unexpected discovery in a very elderly patient. Indeed, even though the discovery was classical, the clinical presentation was singular because of the context.

L'être humain est un hôte intermédiaire accidentel et une impasse parasitaire pour l'échinococcose. Aucun cas de kyste hydatique (échinococcose hydatique) n'a été décrit chez une personne très âgée née en France et ne l'ayant jamais quittée. Nous rapportons ici le cas d'un patient âgé de 90 ans hospitalisé pour altération de l'état général et découverte d'une masse hépatique à la tomodensitométrie. La palpation abdominale était indolore sans masse perçue. Le bilan biologique révélait une hyperéosinophilie, un discret syndrome inflammatoire, une légère augmentation du taux d'immunoglobuline E et une sérologie de l'Echinococcus granulosus positive. Le diagnostic d'échinococcose hydatique (kyste hydatique) due à Echinococcus granulosus fut alors posé, compte tenu de la masse hépatique découverte à la tomodensitométrie, de la sérologie positive et de l'hyperéosinophilie. La prise en charge a consisté en une attitude «watch and wait¼. Cette observation est intéressante car il s'agissait d'un cas de kyste hydatique autochtone de découverte fortuite chez un patient très âgé. En effet, même si le mode de découverte était classique, le tableau clinique était singulier en raison du contexte.

Cáncer de mama triple negativo: terapias sistémicas actuales y experiencia local / Triple negative breast cancer: current systemic therapy and local experience

Resumen El cáncer de mama (CM) es la principal causa de muerte por cáncer en mujeres chilenas. Es una enfermedad heterogénea, en la cual se han identificado cuatro subtipos básicos, determinados según características clínicas, histológicas y moleculares, los que se relacionan a estrategias terapéuticas. El CM triple negativo (CMTN) se caracteriza por su agresividad, recaída temprana y mayor tendencia a presentarse en etapas avanzadas. Frecuentemente afecta a mujeres jóvenes o con antecedentes familiares de CM u ovario. La única terapia sistémica aprobada para el CMTN es la quimioterapia; sin embargo, recientemente terapias moleculares con inhibidores de puntos de control inmune e inhibidores de la poli-adenosina difosfato ribosa polimerasa, han mostrado eficacia en pacientes seleccionados, y se han agregado al arsenal terapéutico para CMTN. Dada la aparición de estas nuevas estrategias, parece relevante entender la heterogeneidad de esta enfermedad, los mecanismos de acción de las nuevas terapias, resultados clínicos y criterios de selección de pacientes para terapias moleculares. Presentamos una revisión de la terapia sistémica actual del CMTN.

Breast cancer is the leading cause of cancer death in Chilean women and worldwide. It is a heterogeneous disease and four different subtypes have been identified based on clinical, histological and molecular features, which correlate with different treatment tumor sensitivity. Triple negative breast cancer is characterized by its aggressiveness, early relapse, and a greater tendency to present in advanced stages. It frequently affects young women, with cancer family history, especially breast or ovarian cancer. The approved systemic therapy for triple negative breast cancer is chemotherapy; however, recently, targeted therapies with checkpoint inhibitors and polyadenosine diphosphate ribose polymerase inhibitors have been shown to be effective in selected patients and have been added to the therapeutic arsenal for triple negative breast cancer. Given the appearance of these new strategies, it seems relevant to understand the heterogeneity of this disease, the mechanisms of action behind new therapies, clinical results, and the criteria to select patients for molecular therapies. We present a review of the current systemic therapy of this breast cancer subtype.

Tetra disseminated microsporidiosis: a novel disease in ornamental fish caused by Fusasporis stethaprioni n. gen. n. sp.

A novel microsporidial disease was documented in two ornamental fish species, black tetra Gymnocorymbus ternetzi Boulenger 1895 and cardinal tetra Paracheirodon axelrodi Schultz 1956. The non-xenoma-forming microsporidium occurred diffusely in most internal organs and the gill, thus referring to the condition as tetra disseminated microsporidiosis (TDM). The occurrence of TDM in black tetra was associated with chronic mortality in a domestic farmed population, while the case in cardinal tetra occurred in moribund fish while in quarantine at a public aquarium. Histology showed that coelomic visceral organs were frequently necrotic and severely disrupted by extensive infiltrates of macrophages. Infected macrophages were presumed responsible for the dissemination of spores throughout the body. Ultrastructural characteristics of the parasite developmental cycle included uninucleate meronts directly in the host cell cytoplasm. Sporonts were bi-nucleated as a result of karyokinesis and a parasite-produced sporophorous vesicle (SPV) became apparent at this stage. Cytokinesis resulted in two spores forming within each SPV. Spores were uniform in size, measuring about 3.9 ± 0.33 long by 2.0 ± 0.2 µm wide. Ultrastructure demonstrated two spore types, one with 9-12 polar filament coils and a double-layered exospore and a second type with 4-7 polar filament coils and a homogenously electron-dense exospore, with differences perhaps related to parasite transmission mechanisms. The 16S rDNA sequences showed closest identity to the genus Glugea (≈ 92%), though the developmental cycle, specifically being a non-xenoma-forming species and having two spores forming within a SPV, did not fit within the genus. Based on combined phylogenetic and ultrastructural characteristics, a new genus (Fusasporis) is proposed, with F. stethaprioni n. gen. n. sp. as the type species.

Linfoma anaplásico de células grandes asociado a implantes mamarios diagnosticado mediante punción por aguja fina. Caso clínico

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare type of non-Hodgkin T-cell lymphoma, recently defined in the 2016 World Health Organization (WHO) classification of lymphoid neoplasms. It occurs more commonly when textured implants are used and appears clinically as a late seroma. Cytologically, these lesions are composed of large atypical cells with pleomorphic nucleus and an immunophenotype positive for T cell markers and CD30, and negative for ALK1. We report a 56-years-old woman with breast implants who developed a periprosthetic seroma three years after surgery. A fine needle aspiration of the lesion was carried out. Cytology and the immunocytochemical study revealed cells compatible with BIA-ALCL. The flow cytometric study was negative. Excisional biopsy of the capsule was performed, observing that the neoplastic cells were confined to the inner surface of the capsule. Imaging studies did not find evidence of disseminated disease. The present case demonstrates the importance of the study of any late periprosthetic effusion, which can be performed using fine needle aspiration.

[Anaplastic large cell lymphoma associated with breast implants, diagnosed by fine needle aspiration. Report of one case]. / Linfoma anaplásico de células grandes asociado a implantes mamarios diagnosticado mediante punción por aguja fina. Caso clínico.

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare type of non-Hodgkin T-cell lymphoma, recently defined in the 2016 World Health Organization (WHO) classification of lymphoid neoplasms. It occurs more commonly when textured implants are used and appears clinically as a late seroma. Cytologically, these lesions are composed of large atypical cells with pleomorphic nucleus and an immunophenotype positive for T cell markers and CD30, and negative for ALK1. We report a 56-years-old woman with breast implants who developed a periprosthetic seroma three years after surgery. A fine needle aspiration of the lesion was carried out. Cytology and the immunocytochemical study revealed cells compatible with BIA-ALCL. The flow cytometric study was negative. Excisional biopsy of the capsule was performed, observing that the neoplastic cells were confined to the inner surface of the capsule. Imaging studies did not find evidence of disseminated disease. The present case demonstrates the importance of the study of any late periprosthetic effusion, which can be performed using fine needle aspiration.

Characterization of spaC-type Erysipelothrix sp. isolates causing systemic disease in ornamental fish.

Since 2012, low-to-moderate mortality associated with an Erysipelothrix sp. bacterium has been reported in ornamental fish. Histological findings have included facial cellulitis, necrotizing dermatitis and myositis, and disseminated coelomitis with abundant intralesional Gram-positive bacterial colonies. Sixteen Erysipelothrix sp. isolates identified phenotypically as E. rhusiopathiae were recovered from diseased cyprinid and characid fish. Similar clinical and histological changes were also observed in zebrafish, Danio rerio, challenged by intracoelomic injection. The Erysipelothrix sp. isolates from ornamental fish were compared phenotypically and genetically to E. rhusiopathiae and E. tonsillarum isolates recovered from aquatic and terrestrial animals from multiple facilities. Results demonstrated that isolates from diseased fish were largely clonal and divergent from E. rhusiopathiae and E. tonsillarum isolates from normal fish skin, marine mammals and terrestrial animals. All ornamental fish isolates were PCR positive for spaC, with marked genetic divergence (<92% similarity at gyrB, <60% similarity by rep-PCR) between the ornamental fish isolates and other Erysipelothrix spp. isolates. This study supports previous work citing the genetic variability of Erysipelothrix spp. spa types and suggests isolates from diseased ornamental fish may represent a genetically distinct species.

Cáncer de mama avanzado receptor de estrógeno positivo: manejo sistémico actual / Systemic therapy for estrogen receptor positive advanced breast cancer

El cáncer de mama es la primera causa de muerte por cáncer en mujeres chilenas. Mientras la mayoría de las personas logra curarse de esta enfermedad, un 5% de los casos se presenta inicialmente con enfermedad avanzada y hasta un 20-30% de pacientes con enfermedad localizada pueden sufrir recurrencias sistémicas. La mayoría de las neoplasias mamarias son dependientes del estímulo estrogénico, de allí que la deprivación de estrógenos es la principal estrategia terapéutica. Recientemente, el uso de terapias molecularmente dirigidas en combinación con la terapia endocrina ha logrado mejorar los resultados de sobrevida del cáncer de mama avanzado, con menos efectos colaterales que aquellos producidos por la quimioterapia convencional. El conocimiento de los mecanismos de acción de estas nuevas terapias, sus toxicidades, vías de resistencia y selección de pacientes para lograr los mejores beneficios terapéuticos son aspectos relevantes en el manejo de la enfermedad. Presentamos una revisión del estado actual del manejo del cáncer de mama metastásico hormonodependiente con enfásis en el uso de terapias endocrinas combinadas con terapias moleculares.

Breast cancer is the leading cause of cancer death in Chilean women. While most patientes are cured, five percent of cases present with advanced disease initially and up to 20-30% of patients with localized disease may suffer systemic recurrences. The majority of breast neoplasms are dependent on the estrogenic stimulus, hence the deprivation of estrogen is the main therapeutic strategy. Recently, the use of molecular targeted therapies in combination with endocrine therapy has been successful in improving the survival outcomes of advanced breast cancer, with fewer side effects than those produced by conventional chemotherapy. Knowledge of the mechanisms of action of these new therapies, their toxicities, resistance pathways and patient selection to achieve the best therapeutic benefits are relevant aspects in the management of the disease. We present a review of the current state of management of hormone-dependent metastatic breast cancer with emphasis on the use of endocrine therapies combined with molecular therapies.

Aplicación de tres modelos pronósticos en cáncer de mama precoz / Application of three prognostic models in T1N0M0 breast cancer

Resumen Objetivo Aplicar tres modelos pronósticos "online" (índice pronóstico de Nothingham (NPI), Adjuvantonline! (AO) y PREDICT utilizados en la práctica oncológica para estratificar a pacientes y definir el uso de terapias adyuvantes en pacientes con cáncer de mama (CM) precoz, para evaluar su correlación y predicción de sobrevida en nuestra población. Métodos Obtuvimos datos clínicos de pacientes con CM invasor T1N0M0, tratados en el Centro de Cáncer de la Pontificia Universidad Católica de Chile, Santiago, Chile, desde enero de 1997 hasta diciembre de 2003. Resultados Analizamos datos de 125 pacientes. Edad mediana fue 55 años (35-80). La mayoría de los tumores fueron carcinomas ductales infiltrantes (72,8%), receptor de estrógeno (RE) positivos (88,8%), 80% recibieron terapia endocrina (TE). El beneficio estimado de la TE y la quimioterapia (QT) en la sobrevida global (SG), determinadas según AO y PREDICT, no fueron significativamente diferentes (1,3% y 1% para QT, p = 0,13; 0,9% y 1% para TE, p = 0,8; respectivamente). El modelo NPI estimó una mediana de SG superior (96%) a la calculada por AO (90,9%) y PREDICT (92,5%). La mortalidad específica por CM fue de 3%, similar a lo observado (3,2%). La mediana de SG estimada por todos los modelos en el grupo de pacientes fallecidos no fue estadísticamente diferente al grupo de sobrevivientes (p = 0,85). Conclusión Los modelos pronósticos predicen apropiadamente la SG en pacientes con CM precoz; sin embargo, en esta serie, no discriminaron pacientes de mal pronóstico.

Objective Apply three prognostic models "online" (Nothingham index (NPI), Adjuvantonline! (AO) and PREDICT used in routine oncology practice in order to stratify patients and define the use of adjuvant therapies in patients with stage I breast cancer (BC) to evaluate its correlation and overall survival (OS) in our population. Methods We obtained patients' medical records data with invasive BC T1N0M0, treated at the Cancer Center of the Pontificia Universidad Católica de Chile, Santiago, Chile, from January 1997 to December 2003. Results We analyzed data from 125 patients. Median age was 55 years (35 80). Most tumors were infiltrating ductal carcinoma (72.8%), estrogen receptor positive (88.8%), 80% received endocrine therapy (ET). The estimated ET and chemotherapy benefit was not significantly different according to the AO and PREDICT models (1.3% and 1% for CT, p = 0.13, 0.9% and 1% for ET p = 0.8, respectively). The estimated median OS on NPI (96%) was higher than calculated by AO (90.9%) and PREDICT (92.5%). Interestingly disease specific mortality estimated was 3%, similar to that observed (3.2%). While the estimated median OS by all models in the group of deceased patients was lower than in surviving, this difference did not reach statistical significance (p = 0.85). Conclusion The prognostic models applied effectively predict OS in Chilean patients with T1N0M0 BC, but in this series, they do not sufficiently discriminate patients with poor prognosis. The addition of co -morbidities to AO does not alter the results.

Pathologic features of mycobacteriosis in naturally infected Syngnathidae and novel transcriptome assembly in association with disease.

Syngnathidae (seahorses, seadragons and pipefish) suffer significant losses from non-tuberculous mycobacteria. However, they produce markedly different lesions in response to the disease compared to other teleost species, notably infrequent granuloma formation. This study evaluated 270 syngnathid fish, from which 92 were diagnosed with mycobacteriosis by histopathology, culture or both. Microscopic lesions variably consisted of random foci of coagulative necrosis in multiple organs, containing high numbers of free bacteria and large aggregates or sheets of macrophages with cytoplasm laden with acid-fast bacilli. Mycobacterial associated granulomas were identified in only six seahorses. Five fish had positive cultures with no observed microscopic changes. RNA-seq of the head kidney was performed to investigate the transcriptome of two infected and six non-infected lined seahorses Hippocampus erectus. Assembled and annotated putative transcripts serve to enrich the database for this species, as well as provide baseline data for understanding the pathogenesis of mycobacteriosis in seahorses. Putative components of the innate immune system (IL-1ß, IL-6, TNF, NOS, Toll-like receptor 1, MHC Class I, NF-κß, transforming growth factor beta, MyD88) were identified in the RNA-seq data set. However, a homolog for a key component in the TH1 adaptive immune response, interferon-gamma, was not identified and may underlie the unique pathologic presentation.

Programa pionero de simulación en sutura para estudiantes de medicina de pregrado / A pioneer simulation curriculum of suture technique training for medical students

Introduction: Simulation has demonstrated utility in suture skills training on surgical residents. Objective: Evaluate validity of a simulated training curriculum of basic suture skills for medical students. Methods: Study conducted on 2013. Medical students were selected from the School of Medicine of Pontificia Universidad Católica de Chile (EMPUC). The program included four theoretical sessions and six practical sessions in order to training basic surgical tasks (five in total) on a simulated rubber model: one handed knot-tying, simple suture, vertical mattress suture, subcuticular interrupted suture and subcuticular running suture. A survey was applied to the participants to qualify each element of the program, on a scale of 1 to 7 (face-validity). One task (simple suture) was recorded on video, before and after training, to be evaluated by two experts on a blind fashion (content validity). Experts measure participant skills using an OSATS (Objective Structured Assessment of Technical Skills) and operative time. Statistical analysis for non-parametric variables, median and interquartile range, significant p-value < 0.05. Results: Thirty-six medical students participated, with assistance percentage was over 80 percent. Students qualified the experience favorably: simulated bench-model 6.0 [5.0-6.0], assistant-students 6.5 [6.0-7.0], practical sessions 7.0 [6.0-7.0], and general evaluation 6.5 [6.0-7.0]. In the evaluation of simple suture, there was a significant improvement on OSATS (10 [5-17] vs 19 [17-21]; p < 0.001) and decrease of operative time (138 seg [101-185] vs 77 seg [67-89]; p < 0.001) after training in every participant. Conclusion: This simulated curriculum delivers an alternative method for the development of technical competencies in medical students and could be incorporated on medical schools curricula.

Introducción: La simulación ha demostrado ser útil en la enseñanza de técnicas de sutura en cirujanos en formación. Objetivo: Evaluar la validez de un programa de entrenamiento simulado de técnica básica de sutura para estudiantes de pregrado de medicina. Material y Métodos: Estudio experimental realizado el año 2013, se seleccionó estudiantes de pregrado de la Escuela de Medicina de la Pontificia Universidad Católica de Chile (EMPUC). El programa incluye 4 sesiones teóricas y 6 prácticas, entrenando 5 tareas en modelo simulado de goma: nudo manual y puntos simple, Donati, intradérmico interrumpido e intradérmico continuo. Se entregó una encuesta a los participantes para calificar cada elemento del curso, en escala de 1 a 7 (validez de apariencia). Se grabó en vídeo una tarea (punto simple), pre y post entrenamiento, para ser evaluadas por 2 cirujanos en forma ciega (validez de contenido). Se utilizó escalas OSATS y medición de tiempo operatorio. Análisis estadístico para variables no paramétricas, mediana y rango interquartil, valor significativo p < 0,05. Resultados: Participaron 36 estudiantes, con un porcentaje de asistencia mayor a un 80 por ciento. Los alumnos calificaron favorablemente la experiencia: simulador de mesa 6,0 [5,0-6,0], ayudantes-alumnos 6,5 [6,0-7,0], clases prácticas 7,0 [6,0-7,0] y evaluación general 6,5 [6,0-7,0]. Respecto al punto simple, hubo mejoría significativa en OSATS (10 [5-17] vs 19 [17-21]; p < 0,001) y disminución de tiempo operatorio (138 seg [101-185] vs 77 seg [67-89]; p < 0,001) al finalizar el entrenamiento. Conclusión: Este programa simulado plantea un método alternativo para el desarrollo de competencias técnicas y podría ser incorporado en los currículos formales de las escuelas de medicina.