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PURPOSE: Receptor and subtype discordance between primary breast tumours and metastases is a frequently reported phenomenon. The aim of this article is to review the current evidence on receptor discordance in metastatic breast cancer and to explore the benefit of performing a repeat biopsy in this context. METHODS: Searches were undertaken on PubMed and Clinicaltrials.gov for relevant publications and trials. CONCLUSION: The current guidelines recommend offering to perform a biopsy of a metastatic lesion to evaluate receptor status. The choice of systemic therapy in metastatic disease is often based on the receptor status of the primary lesion. As therapeutic decision making is guided by subtype, biopsy of the metastatic lesion to determine receptor status may alter treatment. This article discusses discordance rates, the mechanisms of receptor discordance, the effect of discordance on treatment and survival outcomes, as well as highlighting some ongoing clinical trials in patients with metastatic breast cancer.
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Neoplasias de la Mama , Metástasis de la Neoplasia , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Receptor ErbB-2/metabolismo , Receptor ErbB-2/genética , Receptores de Estrógenos/metabolismo , Biomarcadores de Tumor/genética , Receptores de Progesterona/metabolismo , Biopsia , PronósticoRESUMEN
BACKGROUND: Systemic inflammatory response markers have been found to have a prognostic role in several cancers, but their value in predicting the response to neoadjuvant chemotherapy in breast cancer is uncertain. A systematic review and meta-analysis of the literature was carried out to investigate this. METHODS: A systematic search of electronic databases was conducted to identify studies that explored the predictive value of circulating systemic inflammatory response markers in patients with breast cancer before commencing neoadjuvant therapy. A meta-analysis was undertaken for each inflammatory marker where three or more studies reported pCR rates in relation to the inflammatory marker. Outcome data are reported as ORs and 95% confidence intervals. RESULTS: A total of 49 studies were included, of which 42 were suitable for meta-analysis. A lower pretreatment neutrophil-to-lymphocyte ratio was associated with an increased pCR rate (pooled OR 1.66 (95% c.i. 1.32 to 2.09); P < 0.001). A lower white cell count (OR 1.96 (95% c.i. 1.29 to 2.97); P = 0.002) and a lower monocyte count (OR 3.20 (95% c.i. 1.71 to 5.97); P < 0.001) were also associated with a pCR. A higher lymphocyte count was associated with an increased pCR rate (OR 0.44 (95% c.i. 0.30 to 0.64); P < 0.001). CONCLUSION: The present study found the pretreatment neutrophil-to-lymphocyte ratio, white cell count, lymphocyte count, and monocyte count of value in the prediction of a pCR in the neoadjuvant treatment of breast cancer. Further research is required to determine their value in specific breast cancer subtypes and to establish optimal cut-off values, before their adoption in clinical practice.
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Neoplasias de la Mama , Terapia Neoadyuvante , Femenino , Humanos , Biomarcadores de Tumor/sangre , Neoplasias de la Mama/sangre , Neoplasias de la Mama/terapia , Neoplasias de la Mama/tratamiento farmacológico , Quimioterapia Adyuvante , Recuento de Leucocitos , Recuento de Linfocitos , Neutrófilos , Valor Predictivo de las Pruebas , PronósticoRESUMEN
PURPOSE OF REVIEW: In the last decade, poly (ADP-ribose) polymerase (PARP) inhibitors have been approved in the treatment of several cancers, such as breast and ovarian cancer. This article aims to discuss the current uses, limitations, and future directions for PARP inhibitors (PARPis) in the treatment of breast cancer. RECENT FINDINGS: Following the results of the OlympiAD and EMBRACA trials, PARPis were approved in HER2-negative breast cancer with a germline BRCA mutation. We reviewed this class of drugs' mechanism of action, efficacy, and limitations, as well as further studies that discussed resistance, impaired homologous recombination repair (HRR), and the combination of PARPis with other drugs. Improving understanding of HRR, increasing the ability to target resistance, and combining PARPis with other novel agents are continuing to increase the clinical utility of PARPis.
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Neoplasias de la Mama , Neoplasias Ováricas , Femenino , Humanos , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Poli(ADP-Ribosa) Polimerasas/genética , Reparación del ADN , Neoplasias Ováricas/tratamiento farmacológicoRESUMEN
PURPOSE OF REVIEW: Homologous recombination repair deficiency (HRD) increases breast cancer susceptibility and influences both prophylactic and active management of breast cancer. This review evaluates HRD testing and the therapeutic implications of HRD in a global context. RECENT FINDINGS: Ongoing research efforts have highlighted the importance of HRD beyond BRCA1/2 as a potential therapeutic target in breast cancer. However, despite the improved affordability of next-generation sequencing (NGS) and the discovery of PARP inhibitors, economic and geographical barriers in access to HRD testing and breast cancer screening do not allow all patients to benefit from the personalized treatment approach they provide. Advancements in HRD testing modalities and targeted therapeutics enable tailored breast cancer management. However, inequalities in access to testing and optimized treatments are contributing to widening health disparities globally.
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Neoplasias de la Mama , Reparación del ADN por Recombinación , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/diagnóstico , Femenino , Reparación del ADN por Recombinación/genética , Pruebas Genéticas/métodos , Detección Precoz del Cáncer/métodos , Predisposición Genética a la Enfermedad , Proteína BRCA2/genética , Proteína BRCA1/genética , Secuenciación de Nucleótidos de Alto RendimientoRESUMEN
BACKGROUND: Breast cancer surveillance programmes ensure early identification of recurrence which maximises overall survival. Programmes include annual clinical examination and radiological assessment. There remains debate around the value of annual clinical exam in diagnosing recurrent disease/second primaries. The aim was to assess diagnostic modalities for recurrent breast cancer with a focus on evaluating the role of annual clinical examination. PATIENTS AND METHODS: A prospectively maintained database from a symptomatic breast cancer service between 2010-2020 was reviewed. Patients with biopsy-proven recurrence/second breast primary were included. The primary outcome was the diagnostic modality by which recurrences/secondary breast cancers were observed. Diagnostic modalities included (i) self-detection by the patient, (ii) clinical examination by a breast surgeon or (iii) radiological assessment. RESULTS: A total of 233 patients were identified and, following application of exclusion criteria, a total of 140 patients were included. A total of 65/140 (46%) patients were diagnosed clinically, either by self-detection or clinical examination, while 75/140 (54%) were diagnosed radiologically. A total of 59/65 (91%) of patients clinically diagnosed with recurrence presented to the breast clinic after self-detection of an abnormality. Four (6%) patients had cognitive impairment and recurrence was diagnosed by a carer. Two (3%) patients were diagnosed with recurrence by a breast surgeon at clinical examination. The median time to recurrence in all patients was 48 months (range 2-263 months). CONCLUSION: Clinical examination provides little value in diagnosing recurrence (< 5%) and surveillance programmes may benefit from reduced focus on such a modality. Regular radiological assessment and ensuring patients have urgent/easy access to a breast clinic if they develop new symptoms/signs should be the focus of surveillance programmes.
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Neoplasias de la Mama , Femenino , Humanos , Instituciones de Atención Ambulatoria , Biopsia , Neoplasias de la Mama/diagnóstico , Enfermedad Crónica , Estudios de SeguimientoRESUMEN
In 2016 the Choosing Wisely guidelines advised against routine performance of a sentinel lymph node biopsy (SLNB) in women ≥ 70 years of age with clinically node negative (cN0), early-stage, oestrogen receptor positive/ human epidermal growth factor receptor 2 negative (ER+/HER2-), invasive breast cancer. The argument in favour of its continued performance is that it may serve as a useful guide for subsequent management. This systematic review was performed in accordance with the PRISMA guidelines. Studies reporting on rate of adjuvant chemotherapy, adjuvant radiotherapy and performance of completion axillary lymph node dissection (cALND) post SLNB in women aged ≥ 65 years with cN0, early-stage, ER+/HER2-, invasive breast cancer were included. A random effects meta-analysis was performed with summary estimates made using the Mantel-Haenszel method. Dichotomous outcomes were reported as odds ratios (ORs) with 95% confidence intervals (CIs). Ten retrospective studies across 4 countries. Of 105,514 patients, 15,509 had a positive SLNB and 90,005 had a negative SLNB. On meta-analysis, a positive SLNB was significantly associated with receipt of adjuvant chemotherapy (OR 4.64 (95% CI 3.18, 6.77), P < .00001), adjuvant radiotherapy (1.71 (95% CI 1.18, 2.47), P = .005) and undergoing completion axillary lymph node dissection (OR 68.97 (95% CI, 7.47, 636.88), P = .0002). Adjuvant treatment decisions continue to be influenced by SLNB positivity in the era of the Choosing Wisely guidelines. The effects of a positive SLNB and subsequent treatments on outcomes remain inconclusive. However, it is likely clinicians are continuing to over-investigate and over-treat this cohort.
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OBJECTIVES: To validate the Atema and APSI scoring systems in the diagnosis of complicated vs uncomplicated appendicitis. To compare these scoring systems with computed tomography (CT) imaging alone to establish which method provides most accurate prediction of complicated vs uncomplicated appendicitis. METHODS: This was a retrospective review of a sample of 160 patients that underwent appendicectomy and CT imaging for suspected appendicitis between 2018 and 2021 in a tertiary university teaching hospital. Each scoring system was applied to all patients and results analysed and compared with the effectiveness of CT imaging, RESULTS: 32.5% (n = 52) were found to have complicated appendicitis and 67.5% (n = 108) uncomplicated appendicitis. Application of the Atema score to our cohort of patients resulted in a sensitivity 76.9% [CI (64.2, 87.5), specificity 58.7% [CI (48.9, 68.1)], PPV 47.1% [CI (40.5, 53.8) and NPV 84.2% [CI (76.0, 89.9)]. By comparison, the APSI yielded a sensitivity 50.9% [CI (36.6, 65.4)], specificity 76.1% [CI (67.0, 87.8)], PPV 50% [CI (39.2, 60.6)] and NPV 76% [CI (71.1, 81.7)]. Radiology prediction of complicated vs uncomplicated appendicitis with CT imaging showed sensitivity 46% [CI (32.2, 60.5)], specificity 79%; [CI (69.8, 86)], PPV 51% [CI (39.6, 62.5)] and NPV 75% [CI (69.8, 79.9)]. CONCLUSION: By comparing the APSI and Atema et al. scoring systems with CT reporting in our hospital, it appears that the Atema may confer some benefit in stratifying patient risk of complicated versus uncomplicated appendicitis. Further larger scale prospective studies are required.
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Apendicectomía , Apendicitis , Tomografía Computarizada por Rayos X , Apendicitis/diagnóstico por imagen , Apendicitis/cirugía , Humanos , Estudios Retrospectivos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Apendicectomía/estadística & datos numéricos , Sensibilidad y Especificidad , Adulto Joven , Valor Predictivo de las PruebasRESUMEN
Background: Acromioclavicular joint (ACJ) injury is a common orthopaedic condition accounting for over 40 % of all shoulder injuries. The purpose of this study is to assess the research trends and characteristics of the top 50 cited articles on ACJ instability. Methods: A systematic search was conducted in Web of Science to identify articles primarily related to ACJ injury or instability. Characteristics including citation number, country of origin, journal and institution of publication, impact factor, authorship, level of evidence, patient demographics, and study type were analyzed and recorded. Results: Research output on ACJ instability has been steadily increasing, with the top 50 cited studies predominantly presenting Level IV evidence. These studies primarily focused on treatment outcomes which included predominantly male patients and exhibited a large variation in citation counts. The American Journal of Sports Medicine was the most productive journal, and the USA was the most productive nation. Conclusion: There is an increasing number of publications in the ACJ instability literature, primarily concentrated in a few institutions and journals, and focusing mainly on treatment outcomes. A significant portion of these publications are of low scientific quality, and there is a notable lack of research on outcomes for females.
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PURPOSE: There are a wide variety of intraoperative techniques available in breast surgery to achieve low rates for positive margins of excision. The objective of this systematic review was to determine the pooled diagnostic accuracy of intraoperative breast margin assessment techniques that have been evaluated in clinical practice. METHODS: This study was performed in accordance with PRISMA guidelines. A systematic search of the literature was conducted to identify studies assessing the diagnostic accuracy of intraoperative margin assessment techniques. Only clinical studies with raw diagnostic accuracy data as compared with final permanent section histopathology were included in the meta-analysis. A bivariate model for diagnostic meta-analysis was used to determine overall pooled sensitivity and specificity. RESULTS: Sixty-one studies were eligible for inclusion in this systematic review and meta-analysis. Cytology demonstrated the best diagnostic accuracy, with pooled sensitivity of 0.92 (95 % CI 0.77-0.98) and a pooled specificity of 0.95 (95 % CI 0.90-0.97). The findings also indicate good diagnostic accuracy for optical spectroscopy, with a pooled sensitivity of 0.86 (95 % CI 0.76-0.93) and a pooled specificity of 0.92 (95 % CI 0.82-0.97). CONCLUSION: Pooled data indicate that optical spectroscopy, cytology and frozen section have the greatest diagnostic accuracy of currently available intraoperative margin assessment techniques. However, long turnaround time for results and their resource intensive nature has prevented widespread adoption of these methods. The aim of emerging technologies is to compete with the diagnostic accuracy of these established techniques, while improving speed and usability.
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Neoplasias de la Mama , Cuidados Intraoperatorios , Márgenes de Escisión , Sensibilidad y Especificidad , Humanos , Neoplasias de la Mama/cirugía , Neoplasias de la Mama/patología , Femenino , Cuidados Intraoperatorios/métodos , Secciones por Congelación , Periodo Intraoperatorio , Mastectomía Segmentaria/métodosRESUMEN
BACKGROUND: There have been ongoing attempts to de-escalate surgical intervention in older breast cancer patients in recent years. However, there remains ongoing hesitancy amongst surgeons to de-implement axillary staging in this cohort. The supporting argument for performing a sentinel lymph node biopsy (SLNB) is that it may guide subsequent management. METHODS: A retrospective review was performed of 356 SLNBs, in 342 women ≥ 70 years of age with invasive breast cancer, between 2014 and 2022 in a single institution. Data were collected on patient and tumor characteristics and subsequent management for all patients and for patients with ER+/HER2-, early-stage disease. RESULTS: Positive SLNB significantly increased likelihood of receiving adjuvant chemotherapy (CTh) in patients aged 70-75 in all clinical subtypes (OR 4.0, 95% CI, 1.6-10; P = .0035). Positive SLNB did not significantly increase likelihood of receiving adjuvant CTh in patients aged 75-80, however, an Oncotype Dx score of ≥ 26 did (OR 34.50, 95% CI, 3.00-455.2; P = .0103). Positive SLNB was significantly associated with receiving adjuvant radiotherapy (RTh) in all patients aged 70-75 (OR 4.5, 95% CI, 2.0-11; P = .0004) and 75-80 (OR 9.7, 95% CI, 2.7-46; P = .0015). In patients aged ≥ 80 years, positive SLNB did not have a significant influence on subsequent treatments. CONCLUSION: In this study, SLNB did not significantly influence subsequent management decisions in patients over 80 and should rarely be performed in this cohort. However, SLNB still had a role in patients aged 70-80 and should be used selectively in this cohort.
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Neoplasias de la Mama , Biopsia del Ganglio Linfático Centinela , Humanos , Biopsia del Ganglio Linfático Centinela/estadística & datos numéricos , Femenino , Anciano , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Estudios Retrospectivos , Anciano de 80 o más Años , Quimioterapia Adyuvante/métodos , Axila , Estadificación de Neoplasias , Toma de Decisiones Clínicas , Metástasis Linfática/patología , Mastectomía , Ganglio Linfático Centinela/patología , Ganglio Linfático Centinela/cirugíaRESUMEN
Aim: The overamplification of human epidermal growth factor (HER2) in breast cancer (BC) has been the subject of numerous research publications since its discovery in 1987. This is the first bibliometric analysis (BA) conducted on HER2-positive (HER2+) BC. The purpose of this BA is to analyze the published research on HER2+ BC from 1987 to 2024, highlighting the most significant scientific literature, as well as the main contributing authors and journals, and evaluating the impact of clinical and lab-based publications on HER2+ BC research. Methods: The Web of Science Core Collection (WoSCC) was searched using the terms "Breast cancer" OR "Breast carcinoma" OR "Breast tumor" AND "HER2 positive" OR "HER2+". The search was limited by publication year (1987-2024) and only full English articles were included. WoS returned 7,469 relevant results, and from this dataset, a bibliometric analysis was conducted using the "analyze results" and "journal citation report" functions in WoS and the VOSviewer 1.6.16 software to generate bibliographic coupling and co-citation analysis of authors. Results: The analysis encompassed a total of 7,469 publications, revealing a notable increase in the annual number of publications, particularly in recent years. The United States, China, Italy, Germany, and Spain were the top five most prolific countries. The top five significant institutions that published HER2+ research were the University of Texas System, Unicancer, UTMD Anderson Cancer Center, Harvard University, and University of California System. Breast Cancer Research and Treatment, Clinical Cancer Research, and Clinical Breast Cancer were the top three notable journals with the highest number of HER2+ BC publications. Dennis Slamon (Nc = 45,411, H-index = 51) and Jose Baselga (Nc = 32,592, H-index = 55) were the most prolific authors. Evolving research topics include anti-HER2 therapy in the neoadjuvant setting, treatment of metastatic HER2+ BC, and overcoming therapy resistance. Conclusion: This study provides an overview of HER2+ BC research published over the past three decades. It provides insight into the most cited papers and authors, and the core journals, and identifies new trends. These manuscripts have had the highest impact in the field and reflect the continued evolution of HER2 as a therapeutic target in BC.
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Purpose: The development of human epidermal growth factor receptor 2 (HER2)-directed therapies has revolutionized the treatment of HER2-positive breast cancer. The aim of this article is to review the continually evolving treatment strategies in the neoadjuvant setting of HER2-positive breast cancer, as well as the current challenges and future perspectives. Methods: Searches were undertaken on PubMed and Clinicaltrials.gov for relevant publications and trials. Findings: The current standard of care in high-risk HER2-positive breast cancer is to combine chemotherapy with dual anti-HER2 therapy, for a synergistic anti-tumor effect. We discuss the pivotal trials which led to the adoption of this approach, as well as the benefit of these neoadjuvant strategies for guiding appropriate adjuvant therapy. De-escalation strategies are currently being investigated to avoid over treatment, and aim to safely reduce chemotherapy, while optimizing HER2-targeted therapies. The development and validation of a reliable biomarker is essential to enable these de-escalation strategies and personalization of treatment. In addition, promising novel therapies are currently being explored to further improve outcomes in HER2-positive breast cancer.
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Trastuzumab deruxtecan (T-DXd) is a novel antibody-drug-conjugate (ADC), primarily used in the treatment of HER2-positive breast cancer. This study aimed to conduct a systematic review to evaluate the efficacy and safety of T-DXd in treating breast cancer, based on clinical trials. A systematic search of the literature was conducted to identify clinical trials investigating the efficacy and safety of T-DXd in breast cancer. Clinical trials of any phase were included. Outcome measures were any adverse events and survival. Meta-analysis was conducted where possible. Pooled prevalence for each adverse event of any grade and grade 3 or greater were estimated. Progression-free survival (PFS), overall survival (OS) and objective response rates (ORRs) were also reported to evaluate the efficacy of T-DXd in breast cancer. A total of 1593 patients from 6 clinical trials were included. Common adverse events of any grade were nausea, anemia, neutropenia, vomiting, fatigue, constipation and diarrhea, occurring in greater than 30% of cases. In terms of adverse events of grade 3 or more, only anemia and neutropenia occurred at a relatively high rate. Median PFS ranged from 11.1 to 22.1 months. There was evidence of a benefit of T-DXd compared to controls in terms of both PFS (OR: 0.38; 95% CI: 0.32, 0.45) and OS (OR: 0.61; 95% CI: 0.48, 0.78). ORRs ranged from 37% to 79.9%. The present systematic review shows evidence that T-DXd is a safe and effective agent in the treatment of breast cancer based on currently available data. The most common adverse events affected the blood, lymphatic and gastrointestinal systems. Interstitial lung disease (ILD) is a notable and potentially serious adverse event.
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Anemia , Neoplasias de la Mama , Neutropenia , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Trastuzumab/efectos adversos , Camptotecina , Receptor ErbB-2RESUMEN
HYPOTHESIS: Recombinantly modified cells deliver neurotrophic factors with the capacity to induce differentiation and the outgrowth of neurites of rat pheochromocytoma cells 12 (PC12) serving as a neuronal model. BACKGROUND: The benefit of cochlea implant (CI) is depending, among other factors, on the number of surviving spiral ganglion neurons (SGN). Studies have shown that the external application of neurotrophic factors in combination with electrical stimulation increases the survival rate of SGN after ototrauma. Therefore, functionalization of electrodes with recombinantly modified cells providing neurotrophic factors to the SGN for inducing survival mechanisms may be an approach to realize drug delivery to the cochlea. METHODS: Murine NIH3T3 cells were recombinantly modified with an infectious lentiviral monocistronic and bicistronic system to synthesize glial cell line-derived neurotrophic factor and the green fluorescent protein. Free glial cell line-derived neurotrophic factor from the supernatant of the modified NIH3T3 cells was added to rat PC12, and the neuronal-like outgrowth was determined for 10 days. RESULTS: A significant neuronal-like outgrowth appeared as early as Day 3 after the application of the supernatant. CONCLUSION: The results indicate that the established in vitro model represents a powerful basic model for determining signal pathways between neuronal-like processing PC12 cells and cellular drug delivery systems.
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Fibroblastos/fisiología , Factor Neurotrófico Derivado de la Línea Celular Glial/genética , Factor Neurotrófico Derivado de la Línea Celular Glial/fisiología , Neuronas/fisiología , Animales , Axones/ultraestructura , Diferenciación Celular/genética , Ensayo de Inmunoadsorción Enzimática , Vectores Genéticos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Lentivirus/genética , Ratones , Células 3T3 NIH , Células PC12 , RatasRESUMEN
The use of next generation sequencing (NGS) to identify novel viral sequences from eukaryotic tissue samples is challenging. Issues can include the low proportion and copy number of viral reads and the high number of contigs (post-assembly), making subsequent viral analysis difficult. Comparison of assembly algorithms with pre-assembly host-mapping subtraction using a short-read mapping tool, a k-mer frequency based filter and a low complexity filter, has been validated for viral discovery with Illumina data derived from naturally infected liver tissue and simulated data. Assembled contig numbers were significantly reduced (up to 99.97%) by the application of these pre-assembly filtering methods. This approach provides a validated method for maximizing viral contig size as well as reducing the total number of assembled contigs that require down-stream analysis as putative viral nucleic acids.
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Mapeo Contig/métodos , ADN Viral/química , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Algoritmos , Contaminación de ADN , Humanos , Hígado/virología , Análisis de Secuencia de ADN/métodosRESUMEN
Viral emergence as a result of zoonotic transmission constitutes a continuous public health threat. Emerging viruses such as SARS coronavirus, hantaviruses and henipaviruses have wildlife reservoirs. Characterising the viruses of candidate reservoir species in geographical hot spots for viral emergence is a sensible approach to develop tools to predict, prevent, or contain emergence events. Here, we explore the viruses of Eidolon helvum, an Old World fruit bat species widely distributed in Africa that lives in close proximity to humans. We identified a great abundance and diversity of novel herpes and papillomaviruses, described the isolation of a novel adenovirus, and detected, for the first time, sequences of a chiropteran poxvirus closely related with Molluscum contagiosum. In sum, E. helvum display a wide variety of mammalian viruses, some of them genetically similar to known human pathogens, highlighting the possibility of zoonotic transmission.
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Biodiversidad , Quirópteros/virología , Metagenoma , Virus/clasificación , Virus/genética , África , Animales , Análisis por Conglomerados , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADNRESUMEN
Here we describe a virus discovery protocol for a range of different virus genera, that can be applied to biopsy-sized tissue samples. Our viral enrichment procedure, validated using canine and human liver samples, significantly improves viral read copy number and increases the length of viral contigs that can be generated by de novo assembly. This in turn enables the Illumina next generation sequencing (NGS) platform to be used as an effective tool for viral discovery from tissue samples.
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Biopsia , Virus/aislamiento & purificación , Animales , Perros , Humanos , Hígado/virología , ARN Viral/genética , Virus/genéticaRESUMEN
The differentiation of a stem cell is dependent on the environmental cues that it receives and can be modulated by the expression of different master regulators or by secreted factors or inducers. The use of genetically modified stem cells to express the required factors can direct differentiation along the requisite pathway. This approach to the engineering of stem cells is important, as control of the pluripotentiality of stem cells is necessary in order to avoid unwanted growth, migration or differentiation to nontarget tissues. The authors provide an overview of the stem cell engineering field, highlighting challenges and solutions, and focusing on recent developments in therapeutic applications in areas such as autoimmunity, CNS lesions, bone and joint diseases, cancer and myocardial infarction.