A Sensitive Method for Determination 1,25-Dihydroxyvitamin D3 in Human Brain using Ultra-Pressure Liquid Chromatography Tandem Mass Spectrometry.

The hormonally active form of vitamin D, 1,25-Dihydroxyvitamin D3 [1,25(OH)D], has been associated with neuroprotective effects in the brain, but has been difficult to measure in human brain tissue because of its low concentration. The aim of this study was to develop and validate a sensitive method to quantify 1,25(OH)D in the human brain. Prior to analysis by the LC-MS/MS, the samples were derivatized with 4-phenyl-1,2,4-triazoline-3,5-dione.

Vitamin D, Alzheimer's disease and related dementia.

Vitamin D has been proposed as a potential strategy to mitigate age-related cognitive decline and dementia, including Alzheimer's dementia, the predominant type of dementia. Rodent studies have provided insight into the potential mechanisms underlying the role of vitamin D in Alzheimer's disease and dementia. However, inconsistencies with respect to age, sex, and genetic background of the rodent models used poses some limitations regarding scientific rigor and translation.

Filgrastim and infliximab biosimilar uptake in Medicare Advantage compared with Traditional Medicare, 2016-2019.

Background: Medicare Advantage (MA) and Traditional Medicare face different financing structures and incentives and may implement different strategies to encourage biosimilar uptake. Strategies used by health insurers can influence biosimilar uptake, which can in turn promote savings to insurers and patients.

Objective: To compare filgrastim and infliximab biosimilar uptake between MA and Traditional Medicare from 2016 to 2019 and examine biosimilar uptake by different MA carriers and plan types (Health Maintenance Organization [HMO] or Preferred Provider Organization).

Characteristics of Prescription Drug Fills Using Pharmacy-Pharmacy Benefit Manager Discount Programs: The "GoodRx" Model.

Objectives: This study aimed to characterize products using pharmacy-pharmacy benefit manager (PBM) discounts and to estimate the association among such discounts, prescription utilization, and out-of-pocket costs.

Methods: This is a retrospective cohort study using IQVIA's Formulary Impact Analyzer, which contains anonymized, individual-level pharmacy claims representing US retail pharmacy transactions. We focused on 20 products with the greatest number of transactions using a pharmacy-PBM discount.

Accelerated approval drug labels often lack information for clinical decision-making.

Study Objective: We evaluated US Food and Drug Administration labels for drugs approved under the accelerated approval pathway and whether these labels contained in sufficient information regarding their accelerated approval.

Design: Retrospective, observational, cohort study.

Data Source: Label information for drugs with an accelerated approved indication were ascertained from two online platforms: Drugs@FDA and FDA Drug Label Repository.

Medicare Spending on Drugs With Accelerated Approval.

Background: The U.S. Food and Drug Administration provides accelerated approval to drugs on the basis of surrogate end points deemed to be "reasonably likely" to predict clinical benefit.

A model based upon pseudo regular spacing of cells combined with the randomisation of the nuclei can explain the significant changes in high-frequency ultrasound signals during apoptosis.

Recent ultrasound (US) experiments on packed myeloid leukaemia cells have shown that, at frequencies from 32 to 40 MHz, significant increases of signal amplitude were observed during apoptosis. This paper is an attempt to explain these signal increases based upon a simulation of the backscattered signals from the cells nuclei. The simulation is an expansion of work in which a condensed sample of cells, with fairly regular sizes, could be considered as an imperfect crystal.