97 results match your criteria: "1 Harvard Medical School[Affiliation]"

Type I interferon responses are considered the primary means by which viral infections are controlled in mammals. Despite this view, several pathogens activate antiviral responses in the absence of type I interferons. The mechanisms controlling type I interferon-independent responses are undefined.

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Mucociliary clearance, characterized by mucus secretion and its conveyance by ciliary action, is a fundamental physiological process that plays an important role in host defense. Although it is known that ciliary activity changes with chemical and mechanical stimuli, the autoregulatory mechanisms that govern ciliary activity and mucus transport in response to normal and pathophysiological variations in mucus are not clear. We have developed a high-speed, 1-μm-resolution, cross-sectional imaging modality, termed micro-optical coherence tomography (μOCT), which provides the first integrated view of the functional microanatomy of the epithelial surface.

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Perfusion decellularization of whole organs.

Nat Protoc

December 2014

1] Center for Regenerative Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA. [2] Harvard Medical School, Boston, Massachusetts, USA. [3] Department of Surgery, Division of Thoracic Surgery, Massachusetts General Hospital, Boston, Massachusetts, USA. [4] Harvard Stem Cell Institute, Boston, Massachusetts, USA.

The native extracellular matrix (ECM) outlines the architecture of organs and tissues. It provides a unique niche of composition and form, which serves as a foundational scaffold that supports organ-specific cell types and enables normal organ function. Here we describe a standard process for pressure-controlled perfusion decellularization of whole organs for generating acellular 3D scaffolds with preserved ECM protein content, architecture and perfusable vascular conduits.

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Induced pluripotent stem cells in hematology: current and future applications.

Blood Cancer J

May 2014

Retrovirus Centre and Virology Section, Department of Translational Research, University of Pisa, Pisa, Italy.

Reprogramming somatic cells into induced pluripotent stem (iPS) cells is nowadays approaching effectiveness and clinical grade. Potential uses of this technology include predictive toxicology, drug screening, pathogenetic studies and transplantation. Here, we review the basis of current iPS cell technology and potential applications in hematology, ranging from disease modeling of congenital and acquired hemopathies to hematopoietic stem and other blood cell transplantation.

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Poor adherence to AASLD guidelines for chronic hepatitis B Management and treatment in a large academic medical center.

Am J Gastroenterol

June 2014

1] Liver Center and Gastroenterology Division, Massachusetts General Hospital, Boston, Massachusetts, USA [2] Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts, USA [3] Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA.

Objectives: Adherence to the American Association for the Study of Liver Disease (AASLD) guidelines for the management of chronic hepatitis B (CHB) has not been systematically assessed. We sought to comprehensively evaluate adherence to five key areas of these guidelines. We also evaluated physician and patient factors underlying nonadherence, and predictors of nonadherence such as physician type, patient demographic factors, and phase of CHB infection.

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Recurrent somatic mutations in ACVR1 in pediatric midline high-grade astrocytoma.

Nat Genet

May 2014

1] Harvard Medical School, Boston, Massachusetts, USA. [2] Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA. [3] Division of Pediatric Hematology/Oncology, Boston Children's Hospital, Boston, Massachusetts, USA. [4].

Pediatric midline high-grade astrocytomas (mHGAs) are incurable with few treatment targets identified. Most tumors harbor mutations encoding p.Lys27Met in histone H3 variants.

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The routine use of genomic sequencing in clinical medicine has the potential to dramatically alter patient care and medical outcomes. To fully understand the psychosocial and behavioral impact of sequencing integration into clinical practice, it is imperative that we identify the factors that influence sequencing-related decision making and patient outcomes. In an effort to develop a collaborative and conceptually grounded approach to studying sequencing adoption, members of the National Human Genome Research Institute's Clinical Sequencing Exploratory Research Consortium formed the Outcomes and Measures Working Group.

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T2-weighted images are a valuable component of the MRI evaluation of breast masses. Edema, hemorrhage, mucus, and cystic fluid within a lesion are clearly depicted on T2-weighted sequences. In general, masses that have high signal intensity on T2-weighted images are benign; however, breast imagers must be aware of such important exceptions as mucinous carcinoma and necrotic tumors.

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Elafin drives poor outcome in high-grade serous ovarian cancers and basal-like breast tumors.

Oncogene

January 2015

1] Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA [2] Harvard Medical School, Boston, MA, USA [3] Department of Pathology, Brigham and Women's Hospital, Boston, MA, USA.

High-grade serous ovarian carcinoma (HGSOC) and basal-like breast cancer (BLBC) share many features including TP53 mutations, genomic instability and poor prognosis. We recently reported that Elafin is overexpressed by HGSOC and is associated with poor overall survival. Here, we confirm that Elafin overexpression is associated with shorter survival in 1000 HGSOC patients.

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Epigenome-wide association studies without the need for cell-type composition.

Nat Methods

March 2014

eScience Research Group, Microsoft Research, Los Angeles, California, USA.

In epigenome-wide association studies, cell-type composition often differs between cases and controls, yielding associations that simply tag cell type rather than reveal fundamental biology. Current solutions require actual or estimated cell-type composition--information not easily obtainable for many samples of interest. We propose a method, FaST-LMM-EWASher, that automatically corrects for cell-type composition without the need for explicit knowledge of it, and then validate our method by comparison with the state-of-the-art approach.

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Of more than 150 000 published studies evaluating new biomarkers, fewer than 100 biomarkers have been implemented for patient care. One reason for this is lack of rigorous testing by the medical community to validate claims for biomarker clinical relevance, and potential reluctance to publish negative results when confirmation is not obtained. Here we sought to determine the utility and reproducibility of immunohistochemical detection of hepatocyte growth factor (HGF) in melanoma tissue, an approach of potential assistance in defining patients with innate resistance to BRAF inhibitor therapy.

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Exome sequencing identifies BRAF mutations in papillary craniopharyngiomas.

Nat Genet

February 2014

1] Harvard Medical School, Boston, Massachusetts, USA. [2] Department of Pathology, Boston Children's Hospital, Boston, Massachusetts, USA. [3] Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts, USA. [4] Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA. [5].

Craniopharyngiomas are epithelial tumors that typically arise in the suprasellar region of the brain. Patients experience substantial clinical sequelae from both extension of the tumors and therapeutic interventions that damage the optic chiasm, the pituitary stalk and the hypothalamic area. Using whole-exome sequencing, we identified mutations in CTNNB1 (β-catenin) in nearly all adamantinomatous craniopharyngiomas examined (11/12, 92%) and recurrent mutations in BRAF (resulting in p.

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Reduced local mutation density in regulatory DNA of cancer genomes is linked to DNA repair.

Nat Biotechnol

January 2014

1] Division of Genetics, Department of Medicine, Brigham & Women's Hospital, Boston, Massachusetts, USA. [2] Harvard Medical School, Boston, Massachusetts, USA. [3] The Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA.

Carcinogenesis and neoplastic progression are mediated by the accumulation of somatic mutations. Here we report that the local density of somatic mutations in cancer genomes is highly reduced specifically in accessible regulatory DNA defined by DNase I hypersensitive sites. This reduction is independent of any known factors influencing somatic mutation density and is observed in diverse cancer types, suggesting a general mechanism.

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Impaired cerebrovascular hemodynamics are associated with cerebral white matter damage.

J Cereb Blood Flow Metab

February 2014

1] Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts, USA [2] Harvard Medical School, Boston, Massachusetts, USA [3] Department of Neurology, Stroke Division, Brigham and Women's Hospital, Boston, Massachusetts, USA.

White matter hyperintensities (WMH) in elderly individuals with vascular diseases are presumed to be due to ischemic small vessel diseases; however, their etiology is unknown. We examined the cross-sectional relationship between cerebrovascular hemodynamics and white matter structural integrity in elderly individuals with vascular risk factors. White matter hyperintensity volumes, fractional anisotropy (FA), and mean diffusivity (MD) were obtained from MRI in 48 subjects (75±7years).

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Vitamin D status among preterm and full-term infants at birth.

Pediatr Res

January 2014

1] Harvard Medical School, Boston, Massachusetts [2] Division of Newborn Medicine, Boston Children's Hospital, Boston, Massachusetts [3] Division of Newborn Medicine, Brigham and Women's Hospital, Boston, Massachusetts.

Background: Risk factors for maternal vitamin D deficiency and preterm birth overlap, but the distribution of 25-hydroxyvitamin D (25(OH)D) levels among preterm infants is not known. We aimed to determine the associations between 25(OH)D levels and gestational age.

Methods: We measured umbilical cord plasma levels of 25(OH)D from 471 infants born at Brigham and Women's Hospital in Boston.

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Histone deacetylase (HDAC) inhibitors (HDACis) are well-characterized anti-cancer agents with promising results in clinical trials. However, mechanistically little is known regarding their selectivity in killing malignant cells while sparing normal cells. Gene expression-based chemical genomics identified HDACis as being particularly potent against Down syndrome-associated myeloid leukemia (DS-AMKL) blasts.

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Identification of LMX1B as a novel oncogene in human ovarian cancer.

Oncogene

August 2014

1] Department of Pathology, Massachusetts General Hospital, Boston, MA, USA [2] Harvard Medical School, Boston, MA, USA.

Ovarian cancers are thought to result from the accumulation of multiple genetic aberrations that transform ovarian and/or fallopian tube surface epithelial cells, allowing for their abnormal growth, proliferation and metastasis. In the report presented here, we carried out genome-wide copy-number analysis using comparative genomic hybridization on a panel of mouse ovarian cancer (OVCA) cell lines previously established in our laboratory. We identified a recurrent focal amplification on mouse chromosomal region 2qB, which contains the LIM-homeodomain-containing transcription factor 1B (Lmx1b) gene.

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The role of type 2 innate lymphoid cells in asthma.

J Leukoc Biol

November 2013

1.Harvard Medical School, Karp Labs, Room 10127, One Blackfan Circle, Boston, MA 02115, USA. Ya-Jen Chang, Academia Sinica, 128, Sec. 2, Academia Road, Nankang, Taipei 115, Taiwan. E-mail:

Asthma is a complex and heterogeneous disease with several phenotypes, including an allergic asthma phenotype, characterized by Th2 cytokine production and associated with allergen sensitization and adaptive immunity. Asthma also includes nonallergic asthma phenotypes that require innate rather than adaptive immunity. These innate pathways to asthma involve macrophages, neutrophils, as well as ILCs, newly described cell types that produce a variety of cytokines, including IL-5 and IL-13.

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Disruption of MBD5 contributes to a spectrum of psychopathology and neurodevelopmental abnormalities.

Mol Psychiatry

March 2014

1] Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA, USA [2] Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, USA [3] Departments of Genetics and Neurology, Harvard Medical School, Cambridge, MA, USA.

Microdeletions of chromosomal region 2q23.1 that disrupt MBD5 (methyl-CpG-binding domain protein 5) contribute to a spectrum of neurodevelopmental phenotypes; however, the impact of this locus on human psychopathology has not been fully explored. To characterize the structural variation landscape of MBD5 disruptions and the associated human psychopathology, 22 individuals with genomic disruption of MBD5 (translocation, point mutation and deletion) were identified through whole-genome sequencing or cytogenomic microarray at 11 molecular diagnostic centers.

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