Treatment of Organophosphorus Poisoning with 6-Alkoxypyridin-3-ol Quinone Methide Precursors: Resurrection of Methylphosphonate-Aged Acetylcholinesterase.

Organophosphorus (OP) nerve agents inhibit acetylcholinesterase (AChE), creating a cholinergic crisis in which death can occur. The phosphylated serine residue spontaneously dealkylates to the OP-aged form, which current therapeutics cannot reverse. Soman's aging half-life is 4.2 min, so immediate recovery (resurrection) of OP-aged AChE is needed. In 2018, we showed pyridin-3-ol-based quinone methide precursors (QMPs) can resurrect OP-aged electric eel AChE in vitro, achieving 2% resurrection after 24 h of incubation (pH 7, 4 mM). We prepared 50 unique 6-alkoxypyridin-3-ol QMPs with 10 alkoxy groups and five amine leaving groups to improve AChE resurrection. These compounds are predicted in silico to cross the blood-brain barrier and treat AChE in the central nervous system. This library resurrected 7.9% activity of OP-aged recombinant human AChE after 24 h at 250 µM, a 4-fold increase from our 2018 report. The best QMP (1b), with a 6-methoxypyridin-3-ol core and a diethylamine leaving group, recovered 20.8% (1 mM), 34% (4 mM), and 42.5% (predicted maximum) of methylphosphonate-aged AChE activity over 24 h. Seven QMPs recovered activity from AChE aged with Soman and a VX degradation product (EA-2192). We hypothesize that QMPs form the quinone methide (QM) to realkylate the phosphylated serine residue as the first step of resurrection. We calculated thermodynamic energetics for QM formation, but there was no trend with the experimental biochemical data. Molecular docking studies revealed that QMP binding to OP-aged AChE is not the determining factor for the observed biochemical trends; thus, QM formation may be enzyme-mediated.

4-Amidophenol Quinone Methide Precursors: Effective and Broad-Scope Nonoxime Reactivators of Organophosphorus-Inhibited Cholinesterases and Resurrectors of Organophosphorus-Aged Acetylcholinesterase.

Acetylcholinesterase (AChE) inhibition by organophosphorus (OP) compounds poses a serious health risk to humans. While many therapeutics have been tested for treatment after OP exposure, there is still a need for efficient reactivation against all kinds of OP compounds, and current oxime therapeutics have poor blood-brain barrier penetration into the central nervous system, while offering no recovery in activity from the OP-aged forms of AChE. Herein, we report a novel library of 4-amidophenol quinone methide precursors (QMP) that provide effective reactivation against multiple OP-inhibited forms of AChE in addition to resurrecting the aged form of AChE after exposure to a pesticide or some phosphoramidates. Furthermore, these QMP compounds also reactivate OP-inhibited butyrylcholinesterase (BChE) which is an in vivo, endogenous scavenger of OP compounds. The in vitro efficacies of these QMP compounds were tested for reactivation and resurrection of soluble forms of human AChE and BChE and for reactivation of cholinesterases within human blood as well as blood and brain samples from a humanized mouse model. We identify compound 10c as a lead candidate due to its broad-scope efficacy against multiple OP compounds as well as both cholinesterases. With methylphosphonates, compound 10c (250 µM, 1 h) shows >60% recovered activity from OEt-inhibited AChE in human blood as well as mouse blood and brain, thus highlighting its potential for future in vivo analysis. For 10c, the effective concentration (EC50) is less than 25 µM for reactivation of three different methylphosphonate-inhibited forms of AChE, with a maximum reactivation yield above 80%. Similarly, for OP-inhibited BChE, 10c has EC50 values that are less than 150 µM for two different methylphosphonate compounds. Furthermore, an in vitro kinetic analysis show that 10c has a 2.2- and 92.1-fold superior reactivation efficiency against OEt-inhibited and OiBu-inhibited AChE, respectively, when compared to an oxime control. In addition to 10c being a potent reactivator of AChE and BChE, we also show that 10c is capable of resurrecting (ethyl paraoxon)-aged AChE, which is another current limitation of oximes.

Breast cancer survivorship experiences among Black women.

BACKGROUND: Black women experience significant disparities in breast cancer across the care continuum, including survivorship. Ensuring that Black women obtain high-quality follow-up care is critical but understudied. This study was aimed at understanding the experiences and needs of Black women during breast cancer survivorship. METHODS: Black patients diagnosed with invasive breast cancer within the past 5 years were invited to participate in a focus group and complete a survey. Focus groups examined the following: (1) the transition from active treatment to survivorship; (2) interactions with health care providers; (3) survivorship experiences, information needs, and preferences; and (4) existing educational materials. Results were thematically coded and analyzed for main themes. Surveys collected information on sociodemographics, health care experiences, quality of life, lifestyle, and education needs. RESULTS: The study enrolled 53 participants, 43 of whom completed a survey and participated in one of 11 focus groups. The median age was 54 years, 44% had private insurance, 81% were English speaking, and 86% had completed their treatment more than a year before. Participants identified the importance of relationships with health care providers, gaps in survivorship care, experiences with cancer-related symptoms, challenges with mental health, worry about recurrence, body image, cancer financial toxicity, and coping through religion and spirituality. Unmet needs were centered around preparation for long-term symptoms, diet and physical activity, emotional support, and more explanations of information resources. Participants reported preferences for educational videos, personal stories, and culturally relevant content. CONCLUSIONS: Some Black breast cancer survivors may have specific challenges and preferences. Supportive interventions that address these concerns can be responsive and help to ameliorate disparities.

The Role of Race and Insurance Status in Access to Genetic Counseling and Testing Among High-Risk Breast Cancer Patients.

PURPOSE: The role of germline genetic testing in breast cancer patients is crucial, especially in the setting of the recent trials showing the benefit of PARP inhibitors. The goal of this study was to identify racial disparities in genetic counseling and testing in patients with high-risk breast cancer. METHODS: Patients with 2 unique breast cancer diagnoses were examined to understand demographics, insurance coverage, characteristics of breast cancer, and whether they were recommended for and received genetic counseling and testing. RESULTS: A total of 69 patients with a dual diagnosis of breast cancer between the years 2000 and 2017 were identified (42% identified as White compared to 58% that identified as non-White). White patients were more likely to be recommended for genetic counseling (OR = 2.85; 95% CI, 1.07-7.93, P < .05), be referred for genetic counseling (OR = 3.17; 95% CI, 1.19-8.86, P < .05), receive counseling (OR = 3.82; 95% CI, 1.42-10.83, P < .01), and undergo genetic testing (OR = 2.88; 95% CI, 0.97-9.09, P = .056) compared to non-White patients. Patients with private insurance were significantly more likely to be recommended for genetic counseling (OR 5.63, P < .005), referred (OR 6.11, P < .005), receive counseling (OR 4.21, P < .05), and undergo testing (OR 4.10, P < .05). When controlled for insurance, there was no significant racial differences in the rates of GC recommendation, referral, counseling, or testing. CONCLUSION: The findings of this study suggest that disparities in genetic counseling and testing are largely driven by differences in health insurance.

Using fluorescence microscopy to shed light on the mechanisms of antimicrobial peptides.

Antimicrobial peptides (AMPs) are promising in the fight against increasing bacterial resistance, but the development of AMPs with enhanced activity requires a thorough understanding of their mechanisms of action. Fluorescence microscopy is one of the most flexible and effective tools to characterize AMPs, particularly in its ability to measure the membrane interactions and cellular localization of peptides. Recent advances have increased the scope of research questions that can be addressed via microscopy through improving spatial and temporal resolution. Unique combinations of fluorescent labels and dyes can simultaneously consider different aspects of peptide-membrane interaction mechanisms. This review emphasizes the central role that fluorescence microscopy will continue to play in the interrogation of AMP structure-function relationships and the engineering of more potent peptides.