Mayo Clinic

About: Mayo Clinic is a healthcare organization based out in Rochester, Minnesota, United States. It is known for research contribution in the topics: Population & Transplantation. The organization has 63387 authors who have published 169578 publications receiving 8114006 citations.

Clinical practice guideline for diagnostic testing for adult obstructive sleep apnea: An American academy of sleep medicine clinical practice guideline

Abstract: Introduction:This guideline establishes clinical practice recommendations for the diagnosis of obstructive sleep apnea (OSA) in adults and is intended for use in conjunction with other American Aca...

A Randomized Trial of Letrozole in Postmenopausal Women after Five Years of Tamoxifen Therapy for Early-Stage Breast Cancer

Abstract: background In hormone-dependent breast cancer, five years of postoperative tamoxifen therapy — but not tamoxifen therapy of longer duration — prolongs disease-free and overall survival. The aromatase inhibitor letrozole, by suppressing estrogen production, might improve the outcome after the discontinuation of tamoxifen therapy. methods We conducted a double-blind, placebo-controlled trial to test the effectiveness of five years of letrozole therapy in postmenopausal women with breast cancer who have completed five years of tamoxifen therapy. The primary end point was disease-free survival. results A total of 5187 women were enrolled (median follow-up, 2.4 years). At the first interim analysis, there were 207 local or metastatic recurrences of breast cancer or new primary cancers in the contralateral breast — 75 in the letrozole group and 132 in the placebo group — with estimated four-year disease-free survival rates of 93 percent and 87 percent, respectively, in the two groups (P ≤ 0.001 for the comparison of disease-free survival). A total of 42 women in the placebo group and 31 women in the letrozole group died (P=0.25 for the comparison of overall survival). Low-grade hot flashes, arthritis, arthralgia, and myalgia were more frequent in the letrozole group, but vaginal bleeding was less frequent. There were new diagnoses of osteoporosis in 5.8 percent of the women in the letrozole group and 4.5 percent of the women in the placebo group (P=0.07); the rates of fracture were similar. After the first interim analysis, the independent data and safety monitoring committee recommended termination of the trial and prompt communication of the results to the participants. conclusions As compared with placebo, letrozole therapy after the completion of standard tamoxifen treatment significantly improves disease-free survival.

Clonal Hematopoiesis and risk of atherosclerotic cardiovascular disease

Abstract: BackgroundClonal hematopoiesis of indeterminate potential (CHIP), which is defined as the presence of an expanded somatic blood-cell clone in persons without other hematologic abnormalities, is common among older persons and is associated with an increased risk of hematologic cancer. We previously found preliminary evidence for an association between CHIP and atherosclerotic cardiovascular disease, but the nature of this association was unclear. MethodsWe used whole-exome sequencing to detect the presence of CHIP in peripheral-blood cells and associated such presence with coronary heart disease using samples from four case–control studies that together enrolled 4726 participants with coronary heart disease and 3529 controls. To assess causality, we perturbed the function of Tet2, the second most commonly mutated gene linked to clonal hematopoiesis, in the hematopoietic cells of atherosclerosis-prone mice. ResultsIn nested case–control analyses from two prospective cohorts, carriers of CHIP had a risk of c...

The new WHO classification of brain tumours.

Abstract: The new edition of the World Health Organization (WHO) book on 'Histological Typing of Tumours of the Central Nervous System' reflects the progress in brain tumour classification which has been achieved since publication of the first edition in 1979. Several new tumour entities have been added, including the pleomorphic xanthoastrocytoma, central neurocytoma, the infantile desmoplastic astrocytoma/ganglioglioma, and the dysembryoplastic neuroepithelial tumour. The list of histological variants has also been expanded. In line with recent morphological and molecular data on glioma progression, the glioblastoma is now grouped together with astrocytic tumours. The classification of childhood tumours has been largely retained, the diagnosis primitive neuroectodermal tumour (PNET) only being recommended as a generic term for cerebellar medulloblastomas and neoplasms that are histologically indistinguishable from medulloblastoma but located in the CNS at sites other than the cerebellum. The WHO grading scheme was revised and adapted to new entities but its use, as before, remains optional.