FACS to Identify Immune Subsets in Mouse Brain and Spleen.

Flow cytometry enables the multi-parametric quantification of cell types, especially in immunophenotyping of unique immune cell subsets that can either contribute to or ameliorate pathology. For tissues to be used in such analyses, single-cell suspensions must be created. Here we describe protocols for preparing single-cell suspensions of mouse spleen and brain tissue, as well as the steps for fluorescently activated cell staining/sorting (FACS). Specifically, this protocol enables the isolation of lymphocytes for the study of immune responses during various diseases, such as long-term neuroinflammation following ischemic stroke.

The immunopathology of B lymphocytes during stroke-induced injury and repair.

B cells, also known as B lymphocytes or lymphoid lineage cells, are a historically understudied cell population with regard to brain-related injuries and diseases. However, an increasing number of publications have begun to elucidate the different phenotypes and roles B cells can undertake during central nervous system (CNS) pathology, including following ischemic and hemorrhagic stroke. B cell phenotype is intrinsically linked to function following stroke, as they may be beneficial or detrimental depending on the subset, timing, and microenvironment. Factors such as age, sex, and presence of co-morbidity also influence the behavior of post-stroke B cells. The following review will briefly describe B cells from origination to senescence, explore B cell function by integrating decades of stroke research, differentiate between the known B cell subtypes and their respective activity, discuss some of the physiological influences on B cells as well as the influence of B cells on certain physiological functions, and highlight the differences between B cells in healthy and disease states with particular emphasis in the context of ischemic stroke.

Five-year trends in acetaminophen use exceeding the recommended daily maximum dose.

Temporal patterns of acetaminophen use exceeding the recommended daily maximum dosage of 4 g over a 5-year period (4/1/2011-3/31/2016) were evaluated in an online 1-week diary study of 14 434 adult acetaminophen users who also reported acetaminophen use in the previous month. Specific medications taken were identified by list-based prompting; respondents were not required to know their medications contained acetaminophen. Details of use were recorded daily; total daily dosage was determined programmatically. Prevalence of >4 g use over time was modelled and tested for linear changes. The overall prevalence of >4 g use (6.3% of users and 3.7% of usage days) did not change over the 5 years: odds ratio (OR) persons, 1.02 (95% CI, 0.98-1.09); OR days, 0.98 (0.92-1.05). Deviations from label directions were largely unchanged, though concomitant use increased slightly. Thus, over a recent 5-year period, there was no evidence of change in how often acetaminophen use exceeded the labelled maximum daily dose.

Exceeding the maximum daily dose of acetaminophen with use of different single-ingredient OTC formulations.

OBJECTIVES: To assess whether there are differences in the likelihood of exceeding the daily limit of 4 grams of acetaminophen when using different formulations (325 mg, 500 mg, 650 mg) of OTC single-ingredient (SI) acetaminophen medications. DESIGN AND SETTING: Multiyear observational study of acetaminophen use via daily online acetaminophen-usage diaries completed for 7 days. PARTICIPANTS: A total of 7579 U.S. adults from online research panels who used acetaminophen in the month preceding enrollment and used an OTC SI acetaminophen medication during the study. OUTCOME MEASURE: Exceeding the daily dose. RESULTS: On days when 325-mg or 500-mg OTC SI formulations were taken, users were not significantly more likely to exceed 4 grams than on days when OTC SI formulations were not used. On days when 650-mg extended-release (ER) formulations were taken, exceeding 4 grams was significantly more likely (8.9% of days vs. 4.4%; P < 0.0001; median on those days was 5.2 g) than on days with 325- or 500-mg OTC SI formulations. Users of 650-mg ER formulations were significantly less likely to know their dosing interval of 8 hours (33% vs. 49%; P < 0.0001) and more likely to redose too soon (26% vs. 10%; P < 0.0001) and to use other acetaminophen medications concomitantly (14% vs. 7%; P < 0.0001). These patterns were strongest among 650-mg ER products that did not include "8-Hour" in the product name. CONCLUSION: Usage of 500-mg OTC SI acetaminophen formulations does not contribute differently to exceeding dosage compared with other OTC SI acetaminophen formulations. Exceeding 4 grams is more likely when 650-mg ER formulations are used. Improved consumer information on the packages and counseling from pharmacists may help to reduce practices that contribute to exceeding the labeled daily limit of these medications.

Prevalence of exceeding maximum daily dose of paracetamol, and seasonal variations in cold-flu season.

AIMS: To estimate prevalence of excess intake of paracetamol and investigate seasonal variations therein. METHODS: Between 2011 and 2016, 14 481 US adults who used paracetamol in the preceding 30 days were sampled from national online panels and completed a detailed online daily diary of paracetamol medication use for 7 days. Respondents were not told that the study concerned paracetamol. Cold/flu season (CFS), identified using Google Trends data, was contrasted to off-season in symptoms, use of paracetamol medications, and consumption exceeding 4 g (the recommended daily maximum). RESULTS: Overall, 6.3% [95% confidence interval: 5.9-6.7%] of users exceeded 4 g on at least one day; 3.7% [3.5-3.8%] of usage days exceeded 4 g. Cold/flu symptoms were more likely to be experienced and treated with paracetamol in CFS than off-season. Paracetamol users were more likely to exceed 4 g during CFS (6.5% vs. 5.3%; odds ratio = 1.24, 1.04-1.48); days exceeding 4 g also increased (3.9% vs. 2.8%; odds ratio = 1.37, 1.11-1.69). This was not due to differences in characteristics of individuals using paracetamol in CFS, but primarily to increased use of over-the-counter combination medications designed to treat upper respiratory cold/flu symptoms (33.2% of usage days in CFS vs. 24.8% in off-season; odds ratio = 1.58, 1.46-1.72). When such medications were omitted, there was no statistically significant seasonal variation in exceeding 4 g. CONCLUSIONS: Paracetamol use and over-dosing increases in CFS, primarily due to increased use of over-the-counter combinations treating upper respiratory cold/flu symptoms. Pharmacists should warn users to follow labelled dosing directions, especially during CFS.

Patterns of acetaminophen medication use associated with exceeding the recommended maximum daily dose.

BACKGROUND: Acetaminophen overuse has been linked to liver injury. PURPOSE: To identify patterns of medication use associated with exceeding the recommended daily maximum dose of 4 g acetaminophen. METHODS: Respondents from a national panel completed a detailed daily medication diary online for 7 days (n = 5649), identifying medications taken from a comprehensive list of over-the-counter (OTC) and prescription (Rx) acetaminophen medications. Respondents were not told the study concerned acetaminophen. Total daily intake was calculated from diary data. Generalized estimating equations assessed the association of medication patterns with exceeding 4 g per day among 3618 respondents who used acetaminophen medications (on 13,852 days) during the diary period. RESULTS: Acetaminophen intake exceeded 4 g on 3.1% of usage days; median intake on those days was 5.5 g. As expected, days when intake exceeded 4 g were almost always (92%) marked by deviations from label directions-exceeding the one-time dose, re-dosing too soon, and concomitant use of multiple acetaminophen medications. Re-dosing too soon was the most frequent deviation, and concomitant use was most strongly tied to exceeding the daily limit. Use of both an Rx and an OTC medication on the same day also increased the odds of exceeding 4 g on days when concomitant use occurred. CONCLUSIONS: Excess dosing of acetaminophen is associated with deviations from label directions and by use of both OTC and Rx medications containing acetaminophen within a single concomitant use day.