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 & Cancer. The organization has 63387 authors who have published 169578 publications receiving 8114006 citations.

Whole-genome analysis informs breast cancer response to aromatase inhibition

Abstract: Whole-genome analysis of oestrogen-receptor-positive tumours in patients treated with aromatase inhibitors show that distinct phenotypes are associated with specific patterns of somatic mutations; however, most recurrent mutations are relatively infrequent so prospective clinical trials will require comprehensive sequencing and large study populations.

Practice Parameters for Clinical Use of the Multiple Sleep Latency Test and the Maintenance of Wakefulness Test

Abstract: Characterization of excessive sleepiness is an important task for the sleep clinician, and assessment requires a thorough history and in many cases, objective assessment in the sleep laboratory. These practice parameters were developed to guide the sleep clinician on appropriate clinical use of the Multiple Sleep Latency Test (MSLT), and the Maintenance of Wakefulness Test (MWT). These recommendations replace those published in 1992 in a position paper produced by the American Sleep Disorders Association. A Task Force of content experts was appointed by the American Academy of Sleep Medicine to perform a comprehensive review of the scientific literature and grade the evidence regarding the clinical use of the MSLT and the MWT. Practice parameters were developed based on this review and in most cases evidence based methods were used to support recommendations. When data were insufficient or inconclusive, the collective opinion of experts was used to support recommendations. These recommendations were developed by the Standards of Practice Committee and reviewed and approved by the Board of Directors of the American Academy of Sleep Medicine. The MSLT is indicated as part of the evaluation of patients with suspected narcolepsy and may be useful in the evaluation of patients with suspected idiopathic hypersomnia. The MSLT is not routinely indicated in the initial evaluation and diagnosis of obstructive sleep apnea syndrome, or in assessment of change following treatment with nasal continuous positive airway pressure (CPAP). The MSLT is not routinely indicated for evaluation of sleepiness in medical and neurological disorders (other than narcolepsy), insomnia, or circadian rhythm disorders. The MWT may be indicated in assessment of individuals in whom the inability to remain awake constitutes a safety issue, or in patients with narcolepsy or idiopathic hypersomnia to assess response to treatment with medications. There is little evidence linking mean sleep latency on the MWT with risk of accidents in real world circumstances. For this reason, the sleep clinician should not rely solely on mean sleep latency as a single indicator of impairment or risk for accidents, but should also rely on clinical judgment. Assessment should involve integration of findings from the clinical history, compliance with treatment, and, in some cases, objective testing using the MWT. These practice parameters also include recommendations for the MSLT and MWT protocols, a discussion of the normative data available for both tests, and a description of issues that need further study.

Inheritance and Drug Response

Abstract: he promise of pharmacogenetics, the study of the role of in heritance in the individual variation in drug response, lies in its potential to identify the right drug and dose for each patient. Even though individual differences in drug response can result from the effects of age, sex, disease, or drug interactions, genetic factors also influence both the efficacy of a drug and the likelihood of an adverse reaction. 1-3 This article briefly reviews concepts that underlie the emerging fields of pharmacogenetics and pharmacogenomics, with an emphasis on the pharmacogenetics of drug metabolism. Although only a few examples will be provided to illustrate concepts and to demonstrate the potential contribution of pharmacogenetics to medical practice, it is now clear that virtually every pathway of drug metabolism will eventually be found to have genetic variation. The accompanying article by Evans and McLeod 4 expands on many of the themes introduced here. Once a drug is administered, it is absorbed and distributed to its site of action, where it interacts with targets (such as receptors and enzymes), undergoes metabolism, and is then excreted. 5,6 Each of these processes could potentially involve clinically significant genetic variation. However, pharmacogenetics originated as a result of the observation that there are clinically important inherited variations in drug metabolism. Therefore, this article — and the examples highlighted — focuses on the pharmacogenetics of drug metabolism. However, similar principles apply to clinically significant inherited variation in the transport and distribution of drugs and their interaction with their therapeutic targets. The underlying message is that inherited variations in drug effect are common and that some tests that incorporate pharmacogenetics into clinical practice are now available, with many more to follow. The concept of pharmacogenetics originated from the clinical observation that there were patients with very high or very low plasma or urinary drug concentrations, followed by the realization that the biochemical traits leading to this variation were inherited. Only later were the drug-metabolizing enzymes identified, and this discovery was followed by the identification of the genes that encoded the proteins and the DNA-sequence variation within the genes that was associated with the inherited trait. Most of the pharmacogenetic traits that were first identified were monogenic — that is, they involved only a single gene — and most were due to genetic polymorphisms; in other words, the allele or alleles responsible for the variation were relatively common. Although drug effect is a complex phenotype that depends on many factors, early and often dramatic examples involving succinylcholine and isoniazid facilitated acceptance of the fact that inheritance can have an important influence on the effect of a drug. Today there is a systematic search to identify functionally significant variations in DNA sequences in genes that influence the effects of various drugs. 4 t

Clinical practice guideline: Benign paroxysmal positional vertigo

Abstract: Objective This update of a 2008 guideline from the American Academy of Otolaryngology-Head and Neck Surgery Foundation provides evidence-based recommendations to benign paroxysmal positional vertigo (BPPV), defined as a disorder of the inner ear characterized by repeated episodes of positional vertigo. Changes from the prior guideline include a consumer advocate added to the update group; new evidence from 2 clinical practice guidelines, 20 systematic reviews, and 27 randomized controlled trials; enhanced emphasis on patient education and shared decision making; a new algorithm to clarify action statement relationships; and new and expanded recommendations for the diagnosis and management of BPPV. Purpose The primary purposes of this guideline are to improve the quality of care and outcomes for BPPV by improving the accurate and efficient diagnosis of BPPV, reducing the inappropriate use of vestibular suppressant medications, decreasing the inappropriate use of ancillary testing such as radiographic imaging, and increasing the use of appropriate therapeutic repositioning maneuvers. The guideline is intended for all clinicians who are likely to diagnose and manage patients with BPPV, and it applies to any setting in which BPPV would be identified, monitored, or managed. The target patient for the guideline is aged ≥18 years with a suspected or potential diagnosis of BPPV. The primary outcome considered in this guideline is the resolution of the symptoms associated with BPPV. Secondary outcomes considered include an increased rate of accurate diagnoses of BPPV, a more efficient return to regular activities and work, decreased use of inappropriate medications and unnecessary diagnostic tests, reduction in recurrence of BPPV, and reduction in adverse events associated with undiagnosed or untreated BPPV. Other outcomes considered include minimizing costs in the diagnosis and treatment of BPPV, minimizing potentially unnecessary return physician visits, and maximizing the health-related quality of life of individuals afflicted with BPPV. Action Statements The update group made strong recommendations that clinicians should (1) diagnose posterior semicircular canal BPPV when vertigo associated with torsional, upbeating nystagmus is provoked by the Dix-Hallpike maneuver, performed by bringing the patient from an upright to supine position with the head turned 45° to one side and neck extended 20° with the affected ear down, and (2) treat, or refer to a clinician who can treat, patients with posterior canal BPPV with a canalith repositioning procedure. The update group made a strong recommendation against postprocedural postural restrictions after canalith repositioning procedure for posterior canal BPPV. The update group made recommendations that the clinician should (1) perform, or refer to a clinician who can perform, a supine roll test to assess for lateral semicircular canal BPPV if the patient has a history compatible with BPPV and the Dix-Hallpike test exhibits horizontal or no nystagmus; (2) differentiate, or refer to a clinician who can differentiate, BPPV from other causes of imbalance, dizziness, and vertigo; (3) assess patients with BPPV for factors that modify management, including impaired mobility or balance, central nervous system disorders, a lack of home support, and/or increased risk for falling; (4) reassess patients within 1 month after an initial period of observation or treatment to document resolution or persistence of symptoms; (5) evaluate, or refer to a clinician who can evaluate, patients with persistent symptoms for unresolved BPPV and/or underlying peripheral vestibular or central nervous system disorders; and (6) educate patients regarding the impact of BPPV on their safety, the potential for disease recurrence, and the importance of follow-up. The update group made recommendations against (1) radiographic imaging for a patient who meets diagnostic criteria for BPPV in the absence of additional signs and/or symptoms inconsistent with BPPV that warrant imaging, (2) vestibular testing for a patient who meets diagnostic criteria for BPPV in the absence of additional vestibular signs and/or symptoms inconsistent with BPPV that warrant testing, and (3) routinely treating BPPV with vestibular suppressant medications such as antihistamines and/or benzodiazepines. The guideline update group provided the options that clinicians may offer (1) observation with follow-up as initial management for patients with BPPV and (2) vestibular rehabilitation, either self-administered or with a clinician, in the treatment of BPPV.