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Abstract Objective: to explore and describe how perioperative nurses assess and interpret the child's behavior before entering the operating room, identifying the strategies they use to reduce anxiety and the proposals for improvements. Method: descriptive qualitative study using semi-structured interviews and participant observation of daily routines. Thematic analysis of data. This study follows the recommended criteria for publication of articles of the qualitative methodology Consolidated Criteria for Reporting Qualitative Research. Results: four topics emerged from the data: a) assessment of anxiety or close communication with the child and their family; b) evaluating what was observed; c) managing anxiety and d) improving the assessment or proposals for improvements in daily practice. Conclusion: nurses assess anxiety in their daily practice through observation using their clinical judgment. The nurse's experience is decisive for the appropriate assessment of the preoperative anxiety in child. Insufficient time between waiting and entering the operating room, lack of information from child and their parents about the surgical procedure, and parental anxiety make it difficult to assess and properly manage anxiety.

Resumo Objetivo: explorar e descrever como as enfermeiras perioperatórias avaliam e interpretam o comportamento da criança antes de entrar na sala de cirurgia, identificando as estratégias que utilizam para minimizar a ansiedade e as propostas de melhoria. Método: estudo qualitativo descritivo utilizando entrevistas semiestruturadas e observação participante das rotinas diárias. Análise temática dos dados. O estudo segue os critérios recomendados para publicação de artigos da metodologia qualitativa Consolidated Criteria for Reporting Qualitative Research. Resultados: quatro temas emergiram dos dados: a) avaliação da ansiedade ou comunicação próxima com a criança e sua família; b) analisando o que foi observado; c) controlando a ansiedade e d) melhorando a avaliação ou propostas de melhoria na prática diária. Conclusão: as enfermeiras avaliam a ansiedade em sua prática diária por meio da observação e usando julgamento clínico. A experiência da enfermeira é decisiva na avaliação adequada da ansiedade pré-operatória da criança. A falta de tempo entre a espera e o momento de entrar na sala de cirurgia, a escassez de informação que a criança e os pais têm sobre o processo cirúrgico e a ansiedade dos pais, dificultam a avaliação e o controle adequado da ansiedade.

Resumen Objetivo: explorar y describir cómo las enfermeras perioperatorias evalúan e interpretan el comportamiento del niño antes de entrar a quirófano, identificando las estrategias que utilizan para minimizar la ansiedad y las propuestas de mejora. Método: estudio cualitativo descriptivo mediante entrevistas semiestructuradas y observación participante de las rutinas diarias. Análisis temático de los datos. El estudio sigue las recomendaciones de criterios para la publicación de artículos de metodología cualitativa Consolidated Criteria for Reporting Qualitative Research. Resultados: cuatro temas surgieron de los datos: a) evaluación de la ansiedad o comunicación estrecha con el niño y su familia; b) valorando lo observado; c) manejando la ansiedad y d) mejorando la evaluación o propuestas de mejora para la práctica diaria. Conclusión: enfermeras evalúan la ansiedad en su práctica diaria de forma observacional utilizando el juicio clínico. La experiencia de la enfermera es determinante en la adecuada evaluación de la ansiedad prequirúrgica del niño. La falta de tiempo entre la espera y el momento de entrar a quirófano, la mala información que tiene el niño y los padres sobre el proceso quirúrgico y la ansiedad de los padres dificultan la evaluación y el manejo correcto de la ansiedad.

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OBJECTIVE: to explore and describe how perioperative nurses assess and interpret the child's behavior before entering the operating room, identifying the strategies they use to reduce anxiety and the proposals for improvements. METHOD: descriptive qualitative study using semi-structured interviews and participant observation of daily routines. Thematic analysis of data. This study follows the recommended criteria for publication of articles of the qualitative methodology Consolidated Criteria for Reporting Qualitative Research. RESULTS: four topics emerged from the data: a) assessment of anxiety or close communication with the child and their family; b) evaluating what was observed; c) managing anxiety and d) improving the assessment or proposals for improvements in daily practice. CONCLUSION: nurses assess anxiety in their daily practice through observation using their clinical judgment. The nurse's experience is decisive for the appropriate assessment of the preoperative anxiety in child. Insufficient time between waiting and entering the operating room, lack of information from child and their parents about the surgical procedure, and parental anxiety make it difficult to assess and properly manage anxiety.

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Chromosomal instability (CIN) has become a topic of great interest in recent years, not only for its implications in cancer diagnosis and prognosis but also for its role as an enabling feature and central hallmark of cancer. CIN describes cell-to-cell variation in the number or structure of chromosomes in a tumor population. Although extensive research in recent decades has identified some associations between CIN with response to therapy, specific associations with other hallmarks of cancer have not been fully evidenced. Such associations place CIN as an enabling feature of the other hallmarks of cancer and highlight the importance of deepening its knowledge to improve the outcome in cancer. In addition, studies conducted to date have shown paradoxical findings about the implications of CIN for therapeutic response, with some studies showing associations between high CIN and better therapeutic response, and others showing the opposite: associations between high CIN and therapeutic resistance. This evidences the complex relationships between CIN with the prognosis and response to treatment in cancer. Considering the above, this review focuses on recent studies on the role of CIN in cancer, the cellular mechanisms leading to CIN, its relationship with other hallmarks of cancer, and the emerging therapeutic approaches that are being developed to target such instability, with a primary focus on breast cancer. Further understanding of the complexity of CIN and its association with other hallmarks of cancer could provide a better understanding of the cellular and molecular mechanisms involved in prognosis and response to treatment in cancer and potentially lead to new drug targets.

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Primary breast angiosarcoma, with de novo appearance and not associated with exposure to radiation or lymphedema, is a rare pathology representing less than 0.05% of the neoplasms related to this organ. The pathology is characterized by its aggressiveness, poor prognosis, and difficulties in its differential diagnosis. This article reports the case of a 55-year-old white woman with no family history of cancer, with a rapidly growing mass in the left mammary gland that ulcerates and bleeds. It is confirmed as primary breast angiosarcoma by immunostaining in the tumor tissue for CD31, CD34, and FLI-1. In addition, a sample of neoplastic and healthy tissues is collected from the patient for RNA sequencing; the results are contrasted with a tissue sample from a patient with Luminal A subtype of breast cancer, as well as data from other cases of angiosarcoma available in public databases. These findings revealed a genetic profile associated with the immune and inflammatory response in the patient's sample when compared to available angiosarcoma data; these molecular patterns are consistent with other recent studies. Due to the rarity of the disease, the studies carried out on each patient contribute to the expanding knowledge of the etiology and molecular pathways that are still partially known and continue to be the subject of research. Aside from a comparative transcriptome study, this article aims to provide an update on the state of knowledge about this disease.

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Exosomes carry molecules of great biological and clinical interest, such as miRNAs. The contents of exosomes vary between healthy controls and cancer patients. Therefore, miRNAs and other molecules transported in exosomes are considered a potential source of diagnostic and prognostic biomarkers in cancer. Many miRNAs have been detected in recent years. Consequently, a substantial amount of miRNA-related data comparing patients and healthy individuals is available, which contributes to a better understanding of the initiation, development, malignancy, and metastasis of cancer using non-invasive sampling procedures. However, a re-analysis of available ncRNA data is rare. This study used available data about miRNAs in exosomes comparing healthy individuals and cancer patients to identify possible global changes related to the presence of cancer. A robust transcriptomic analysis identified two common miRNAs (miR-495-3p and miR-543) deregulated in five cancer datasets. They had already been implicated in different cancers but not reported in exosomes circulating in blood. The study also examined their target genes and the implications of these genes for functional processes.

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BACKGROUND: Pathogenic germline mutations in the BRCA1 and BRCA2 (BRCA1/2) genes contribute to hereditary breast/ovarian cancer (OC) in White/mestizo Colombian women. As there is virtually no genetic data on breast cancer (BC) in Colombians of African descent, we conducted a comprehensive BRCA1/2 mutational analysis of 60 Afro-Colombian families affected by breast/OC. MATERIALS AND METHODS: Mutation screening of the complete BRCA1/2 genes for small-scale mutations and large genomic alterations was performed in these families using next-generation sequencing and multiplex ligation-dependent probe amplification analysis. RESULTS: Four pathogenic germline mutations, including one novel mutation, were identified, comprising 3 in BRCA1 and one in BRCA2. The prevalence of BRCA1/2 mutations, including one BRCA1 founder mutation (c.5123C>A) previously identified in this sample set, was 3.9% (2/51) in female BC-affected families and 33.3% (3/9) in those affected by both breast and OC. Haplotype analysis of 2 BRCA2_c.2701delC carriers (one Afro-Colombian and one previously identified White/mestizo Colombian patient with BC) suggested that the mutation arose in a common ancestor. CONCLUSION: Our data showed that 2/5 (40%) mutations (including the one previously identified in this sample set) are shared by White/mestizo Colombian and Afro-Colombian populations. This suggests that these 2 populations are closely related. Nevertheless, variations in the BRCA1/2 mutational spectrum among Afro-Colombian subgroups from different regions of the country were observed, suggesting that specific genetic risk assessment strategies need to be developed.

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Noncoding RNAs (ncRNAs) play prominent roles in the regulation of gene expression via their interactions with other biological molecules such as proteins and nucleic acids. Although much of our knowledge about how these ncRNAs operate in different biological processes has been obtained from experimental findings, computational biology can also clearly substantially boost this knowledge by suggesting possible novel interactions of these ncRNAs with other molecules. Computational predictions are thus used as an alternative source of new insights through a process of mutual enrichment because the information obtained through experiments continuously feeds through into computational methods. The results of these predictions in turn shed light on possible interactions that are subsequently validated experimentally. This review describes the latest advances in databases, bioinformatic tools, and new in silico strategies that allow the establishment or prediction of biological interactions of ncRNAs, particularly miRNAs and lncRNAs. The ncRNA species described in this work have a special emphasis on those found in humans, but information on ncRNA of other species is also included.

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The androgen receptor (AR) is frequently expressed in breast cancer (BC), but its association with clinical and biological parameters of BC patients remains unclear. Here, we investigated the association of AR gene expression according to intrinsic BC subtypes by meta-analysis of large-scale microarray transcriptomic datasets. Sixty-two datasets including 10315 BC patients were used in the meta-analyses. Interestingly, AR mRNA level is significantly increased in patients categorized with less aggressive intrinsic molecular subtypes including, Luminal A compared to Basal-like (standardized mean difference, SMD: 2.12; 95% confidence interval, CI: 1.88 to 2.35; p < 0.001) or when comparing Luminal B to Basal-like (SMD: 1.53; CI: 1.33 to 1.72; p < 0.001). The same trend was observed when analyses were performed using immunohistochemistry-based surrogate subtypes. Consistently, the AR mRNA expression was higher in patients with low histological grade (p < 0.001). Furthermore, our data revealed higher levels of AR mRNA in BC patients expressing either estrogen or progesterone receptors (p < 0.001). Together, our findings indicate that high mRNA levels of AR are associated with BC subgroups with the less aggressive clinical features.

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Obesity is an increasing health challenge and is recognized as a breast cancer risk factor. Although obesity-related breast cancer mechanisms are not fully understood, this association has been linked to impaired hormone secretion by the dysfunctional obese adipose tissue (hyperplasic and hypertrophic adipocytes). Among these hormones, altered production of androgens and adipokines is observed, and both, are independently associated with breast cancer development. In this review, we describe and comment on the relationships reported between these factors and breast cancer, focusing on the biological associations that have helped to unveil the mechanisms by which signaling from androgens and adipokines modifies the behavior of mammary epithelial cells. Furthermore, we discuss the potential crosstalk between the two most abundant adipokines produced by the adipose tissue (adiponectin and leptin) and the androgen receptor, an emerging marker in breast cancer. The identification and understanding of interactions among adipokines and the androgen receptor in cancer cells are necessary to guide the development of new therapeutic approaches in order to prevent and cure obesity and breast cancer.

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Resumen El espectro clínico de la hemofilia severa ha evolucionado a lo largo de la historia desde una condición catastrófica y altamente fatal a principios del siglo xx, hasta un trastorno crónico y «manejable¼ en las últimas décadas, gracias a los notables avances en el tratamiento alcanzados en los últimos 40 años, avances impulsados y reforzados por algunas experiencias catastróficas pasadas, como lo fue el desastre biológico en la década de 1980 debido a infecciones virales fatales transmitidas por trasfusión, como hepatitis y virus de la inmunodeficiencia humana/sida, a partir de lo cual la aparición de nuevos agentes infecciosos son una preocupación constante para la comunidad de hemofilia, como lo es actualmente el caso al que nos enfrentamos con la pandemia de enfermedad por coronavirus 2019, que ha creado una situación extremadamente desafiante para los miembros de la comunidad mundial de trastornos hemorrágicos. Ante esta pandemia han surgido interrogantes sobre la posibilidad de si los pacientes con hemofilia tendrán mayor riesgo de infección y si la deficiencia de factor y su tratamiento podrían influir en las manifestaciones de la infección, su curso natural, tratamiento y complicaciones; aunado a la preocupación de que parece claro que la pandemia actual tendrá consecuencias definitivas sobre el manejo de la hemofilia en todo el mundo. Tales interrogantes han dado lugar a la revisión de la literatura, guías, consensos de expertos, incluyendo las recomendaciones de la Federación Mundial de Hemofilia, en un intento de responder a dichas interrogantes, generando así tanto pautas para la atención como ampliando algunas de ellas, impulsando el desarrollo de nuevos protocolos de investigación.

Abstract The clinical spectrum of severe hemophilia has evolved throughout history from a catastrophic and highly fatal condition in the early 20th century to a chronic and “manageable” disorder in recent decades, thanks to the remarkable advances in treatment achieved. in the last 40 years, advances driven and reinforced by some past catastrophic experiences, such as the biological disaster in the 1980s due to fatal viral infections transmitted by transfusion, such as hepatitis and HIV/AIDS, from which, the appearance of new infectious agents are an ongoing concern for the hemophilia community, as is currently the case facing us with the coronavirus disease 2019 pandemic, which has created an extremely challenging situation for members of the global bleeding disorders community. Faced with this pandemic, questions have arisen regarding the possibility of whether patients with hemophilia will have a higher risk of infection and whether factor deficiency and its treatment could influence the manifestations of the infection, its natural course, treatment and complications; coupled with the concern that it seems clear that the current pandemic will have definitive consequences on the management of hemophilia around the world. Such questions have led to a review of the literature, guidelines, and expert consensus, including the recommendations of the World Federation of Hemophilia, in an attempt to answer these questions, thus generating both guidelines for care, and expanding some of them, promoting the development of new research protocols.

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Objective: Chromosomal instability (CIN) is a hallmark of cancer characterized by cell-to-cell variability in the number or structure of chromosomes, frequently observed in cancer cell populations and is associated with poor prognosis, metastasis, and therapeutic resistance. Breast cancer (BC) is characterized by unstable karyotypes and recent reports have indicated that CIN may influence the response of BC to chemotherapy regimens. However, paradoxical associations between extreme CIN and improved outcome have been observed. Methods: This study aimed to 1) evaluate CIN levels and clonal heterogeneity (CH) in MCF7, ZR-751, MDA-MB468, BT474, and KPL4 BC cells treated with low doses of tamoxifen (TAM), docetaxel (DOC), doxorubicin (DOX), Herceptin (HT), and combined treatments (TAM/DOC, TAM/DOX, TAM/HT, HT/DOC, and HT/DOX) by using fluorescence in situ hybridization (FISH), and 2) examine the association with response to treatments by comparing FISH results with cell proliferation. Results: Intermediate CIN was linked to drug sensitivity according to three characteristics: estrogen receptor α (ERα) and HER2 status, pre-existing CIN level in cancer cells, and the CIN induced by the treatments. ERα+/HER2- cells with intermediate CIN were sensitive to treatment with taxanes (DOC) and anthracyclines (DOX), while ERα-/HER2-, ERα+/HER2+, and ERα-/HER2+ cells with intermediate CIN were resistant to these treatments. Conclusions: A greater understanding of CIN and CH in BC could assist in the optimization of existing therapeutic regimens and/or in supporting new strategies to improve cancer outcomes.

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The incidence and mortality of breast cancer (BC) have increased in recent years, and BC is the main cause of cancer-related death in women worldwide. One of the most significant clinical problems in the treatment of patients with BC is the development of therapeutic resistance. Therefore, elucidating the molecular mechanisms involved in drug resistance is critical. The therapeutic decision for the management of patients with BC is based not only on the assessment of prognostic factors but also on the evaluation of clinical and pathological parameters. Although this has been a successful approach, some patients relapse and/or eventually develop resistance to treatment. This review is focused on recent studies on the possible biological and molecular mechanisms involved in both response and resistance to treatment in BC. Additionally, emerging treatments that seek to overcome resistance and reduce side effects are also described. A greater understanding of the mechanisms of action of treatments used in BC might contribute not only to the enhancement of our understanding of the mechanisms involved in the development of resistance but also to the optimization of the existing treatment regimens.

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Abstract Background: Hemophagocytic lymphohistiocytosis (HLH) is considered a medical emergency that should be recognized in patients with fever, splenomegaly, and progressive deterioration of the general condition. Laboratory findings include cytopenia, hypertriglyceridemia, hypofibrinogenemia, and hyperferritinemia. For HLH diagnosis, it is essential, although not mandatory, to perform a bone marrow biopsy. Given its nature, secondary causes of HLH should be sought, mainly infections, hemato-oncological disorders, autoimmune diseases, and auto-inflammatory conditions. Case report: We present the case of a female adolescent who presented with fever and lower gastrointestinal bleeding. Upon admission, acute liver failure and pancytopenia were documented. A bone marrow aspirate was performed, which revealed hemophagocytosis; other tests confirmed HLH diagnosis. During the diagnostic approach, inflammatory bowel disease was diagnosed. The patient received first-line treatment with an adequate response. Conclusions: Inflammatory bowel disease can be considered a cause of secondary HLH, particularly in patients with suggestive symptoms, such as digestive bleeding in the absence of other secondary causes of HLH.

Resumen Introducción: La linfohistiocitosis hemofagocítica (LHH) es considerada una urgencia médica que debe reconocerse en pacientes con deterioro progresivo del estado general, fiebre, pancitopenia y esplenomegalia. Los hallazgos de laboratorio incluyen citopenia, hipertrigliceridemia, hipofibrinogenemia e hiperferritinemia. Para su diagnóstico es importante, aunque no obligatoria, la realización de aspirado de médula ósea. Dada su naturaleza, se deben buscar causas secundarias de LHH, principalmente enfermedades infecciosas, hematooncológicas, autoinmunitarias y autoinflamatorias. Caso clínico: Se presenta el caso de una adolescente que inició con fiebre y sangrado digestivo bajo. A su ingreso, se documentó falla hepática aguda y pancitopenia. Se realizó aspirado de médula ósea y se encontró hemofagocitocis; el resto de los exámenes concluyeron LHH. Durante su abordaje se diagnosticó enfermedad inflamatoria intestinal. La paciente recibió tratamiento de primera línea con adecuada respuesta. Conclusiones: La enfermedad inflamatoria intestinal puede considerarse como una causa secundaria de LHH, en particular en pacientes con clínica sugestiva, como es el sangrado digestivo, en ausencia de otras causas secundarias de LHH.

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Background: Hemophagocytic lymphohistiocytosis (HLH) is considered a medical emergency that should be recognized in patients with fever, splenomegaly, and progressive deterioration of the general condition. Laboratory findings include cytopenia, hypertriglyceridemia, hypofibrinogenemia, and hyperferritinemia. For HLH diagnosis, it is essential, although not mandatory, to perform a bone marrow biopsy. Given its nature, secondary causes of HLH should be sought, mainly infections, hemato-oncological disorders, autoimmune diseases, and auto-inflammatory conditions. Case report: We present the case of a female adolescent who presented with fever and lower gastrointestinal bleeding. Upon admission, acute liver failure and pancytopenia were documented. A bone marrow aspirate was performed, which revealed hemophagocytosis; other tests confirmed HLH diagnosis. During the diagnostic approach, inflammatory bowel disease was diagnosed. The patient received first-line treatment with an adequate response. Conclusions: Inflammatory bowel disease can be considered a cause of secondary HLH, particularly in patients with suggestive symptoms, such as digestive bleeding in the absence of other secondary causes of HLH.

Introducción: La linfohistiocitosis hemofagocítica (LHH) es considerada una urgencia médica que debe reconocerse en pacientes con deterioro progresivo del estado general, fiebre, pancitopenia y esplenomegalia. Los hallazgos de laboratorio incluyen citopenia, hipertrigliceridemia, hipofibrinogenemia e hiperferritinemia. Para su diagnóstico es importante, aunque no obligatoria, la realización de aspirado de médula ósea. Dada su naturaleza, se deben buscar causas secundarias de LHH, principalmente enfermedades infecciosas, hematooncológicas, autoinmunitarias y autoinflamatorias. Caso clínico: Se presenta el caso de una adolescente que inició con fiebre y sangrado digestivo bajo. A su ingreso, se documentó falla hepática aguda y pancitopenia. Se realizó aspirado de médula ósea y se encontró hemofagocitocis; el resto de los exámenes concluyeron LHH. Durante su abordaje se diagnosticó enfermedad inflamatoria intestinal. La paciente recibió tratamiento de primera línea con adecuada respuesta. Conclusiones: La enfermedad inflamatoria intestinal puede considerarse como una causa secundaria de LHH, en particular en pacientes con clínica sugestiva, como es el sangrado digestivo, en ausencia de otras causas secundarias de LHH.

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Asbestos is one of the most important occupational carcinogens. Currently, about 125 million people worldwide are exposed to asbestos in the workplace. According to global estimates, at least 107,000 people die each year from lung cancer, mesothelioma, and asbestosis as a result of occupational exposure to asbestos. The high pathogenicity of this material is currently known, being associated with the development of pulmonary diseases, of which lung cancer is the main cause of death due to exposure to this mineral. Pulmonary diseases related to asbestos are a common clinical problem and a major health concern worldwide. Extensive research has identified many important pathogenic mechanisms; however, the precise molecular mechanisms involved, and the generated genomic damage that lead to the development of these diseases, are not completely understood. The modes of action that underlie this type of disease seem to differ depending on the type of fiber, lung clearance, and genetics. This evidences the need to increase our knowledge about these effects on human health. This review focuses on the characteristics of asbestos and the cellular and genomic damage generated in humans via exposure.

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Cancer is one of the leading causes of death, and despite increased research in recent years, control of advanced-stage disease and optimal therapeutic responses remain elusive. Recent technological improvements have increased our understanding of human cancer as a heterogeneous disease. For instance, four hallmarks of cancer have recently been included, which in addition to being involved in cancer development, could be involved in therapeutic responses and resistance. One of these hallmarks is chromosome instability (CIN), a source of genetic variation in either altered chromosome number or structure. CIN has become a hot topic in recent years, not only for its implications in cancer diagnostics and prognostics, but also for its role in therapeutic responses. Chromosomal alterations are mainly used to determine genetic heterogeneity in tumors, but CIN could also reveal treatment efficacy, as many therapies are based on increasing CIN, which causes aberrant cells to undergo apoptosis. However, it should be noted that contradictory findings on the implications of CIN for the therapeutic response have been reported, with some studies associating high CIN with a better therapeutic response and others associating it with therapeutic resistance. Considering these observations, it is necessary to increase our understanding of the role CIN plays not only in tumor development, but also in therapeutic responses. This review focuses on recent studies that suggest possible mechanisms and consequences of CIN in different disease types, with a primary focus on cancer outcomes and therapeutic responses.

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Objectives Hematopoietic stem cell transplantation (HSCT) from a matched sibling donor (MSD) is the preferred initial treatment for children with severe aplastic anemia (SAA). Unfortunately, only about 30% of patients have a suitable human leukocyte antigen-matched sibling. Methods We have analyzed the outcome of 42 patients who received HSCT (22 MSD and 20 alternative donors (AD)) for SAA at the seven major pediatric HSCT centers in Mexico between 2001 and 2013. Results With a median follow-up of 30 months (range, 0.4-144), the 5-year overall survival in children transplanted from MSD was 86.4 + 7.3 vs. 49.5 + 11% for children after AD-HSCT (P = 0.013). The cumulative incidence of treatment-related mortality (TRM) was in the MSD-HSCT 9.1 + 3.9% vs. 47.6 + 9.1% in the AD-HSCT context (P = 0.007). Infectious complications contributed to death (91%) of most patients who received AD-HSCT. Discussion Even when the results of patients given MSD-HSCT are adequate, there is still much room for improvement particularly in children allografted with AD and in the supportive care. The development of an economicwise designed prospective project with MSD or matched unrelated donor HSCTs as a first line of treatment of children with SAA as a unified national trial could address these issues.

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Non-coding RNAs are a complex class of nucleic acids, with growing evidence supporting regulatory roles in gene expression. Here we identify a non-coding RNA located head-to-head with the gene encoding the Glioma-associated oncogene 1 (GLI1), a transcriptional effector of multiple cancer-associated signaling pathways. The expression of this three-exon GLI1 antisense (GLI1AS) RNA in cancer cells was concordant with GLI1 levels. siRNAs knockdown of GLI1AS up-regulated GLI1 and increased cellular proliferation and tumor growth in a xenograft model system. Conversely, GLI1AS overexpression decreased the levels of GLI1, its target genes PTCH1 and PTCH2, and cellular proliferation. Additionally, we demonstrate that GLI1 knockdown reduced GLI1AS, while GLI1 overexpression increased GLI1AS, supporting the role of GLI1AS as a target gene of the GLI1 transcription factor. Activation of TGFß and Hedgehog signaling, two known regulators of GLI1 expression, conferred a concordant up-regulation of GLI1 and GLI1AS in cancer cells. Finally, analysis of the mechanism underlying the interplay between GLI1 and GLI1AS indicates that the non-coding RNA elicits a local alteration of chromatin structure by increasing the silencing mark H3K27me3 and decreasing the recruitment of RNA polymerase II to this locus. Taken together, the data demonstrate the existence of a novel non-coding RNA-based negative feedback loop controlling GLI1 levels, thus expanding the repertoire of mechanisms regulating the expression of this oncogenic transcription factor.

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Los defectos cardiacos conforman las malformaciones congénitas más frecuentes, con una incidencia que se ha estimado entre 4 y 12 por 1000 en recién nacidos vivos. Estos tienen una etiología multifactorial en la que convergen la predisposición genética y los factores ambientales. A partir de 1990 se ha relacionado este tipo de patologías con microdelección 22q11. Se determinó la frecuencia de la microdeleción 22q11 en pacientes con cardiopatía congénita no sindrómica. Se analizaron 61 pacientes con cardiopatía congénita, a partir de ADN de sangre periférica y posterior amplificación, mediante PCR multiplex del gen TUPLE1 y del STR D10S2198, visualización electroforesis en geles de agarosa y análisis densitométrico para determinar dosis génica. Se encontraron 3 pacientes con microdeleción 22q11, para una frecuencia de 4,9%. Esta microdeleción se asoció en dos de los casos a Tetralogía de Fallot y en el otro a Defecto Septal Atrial (DSA). En conclusión, la frecuencia de microdeleción 22q11 en la población analizada es de 4,9%. Dentro de los casos de Tetralogía de Fallot, la microdeleción estaba presente en el 7,4% y en los DSA corresponde al 11,1%.

Cardiac defects are the most frequent congenital malformations, with an incidence estimated between 4 and 12 per 1000 newborns. Their etiology is multifactorial and might be attributed to genetic predispositions and environmental factors. Since 1990 these types of pathologies have been associated with 22q11 microdeletion. In this study, the frequency of microdeletion 22q11 was determined in 61 patients with non-syndromic congenital heart disease. DNA was extracted from peripheral blood and TUPLE1 and STR D10S2198 genes were amplified by multiplex PCR and visualized in agarose gels. Gene content was quantified by densitometry. Three patients were found with microdeletion 22q11, representing a 4.9% frequency. This microdeletion was associated with two cases of Tetralogy of Fallot and a third case with atrial septal defect (ASD). In conclusion, the frequency for microdeletion 22q11 in the population analyzed was 4.9%. The cases that presented Teratology of Fallot had a frequency for this microdeletion of 7.4% and for ASD of 11.1%.

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High prevalence of somatic mutations in the cardiac transcription factor genes NKX2.5 and GATA4 have been reported in the affected cardiovascular tissue of patients with isolated cardiac septal defects, suggesting a role of somatic mutations in the pathogenesis of these congenital heart defects (CHDs). However, all somatic mutations have been identified in DNA extracted from an archive of formalin-fixed cardiac tissues. In the present study, to address the hypothesis that somatic mutations are important in isolated CHDs, we analyzed the GATA4 and NKX2.5 genes in the fresh-frozen pathologic cardiac tissue specimen and corresponding non-diseased tissue obtained from a series of 62 CHD patients, including 35 patients with cardiac septal defects and 27 with other cardiac anomalies. We identified one variant and two common polymorphisms in the NKX2.5 gene, and six variants and two common polymorphisms in the GATA4 gene. All identified variants were seen in both the fresh-frozen pathologic cardiac tissue and the corresponding non-diseased tissue, which indicates that they all were constitutional variants. The present study has identified NKX2.5 and GATA4 constitutional variants in our CHD cohort, but was unable to replicate the previously published findings of high prevalence of somatically derived sequence mutations in patients with cardiac septal defects using fresh-frozen cardiac tissues rather than formalin-fixed tissues.

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