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This study examines predictors of readiness to change smoking behavior in a sample of smokers who receive care at a community health center that serves a predominantly low income African American population. Prior to initiating interventions we conducted a telephone survey with a random sample of 1318 adult users who had visited the center in the last 18 months, 379 (28.8%) were current smokers (40.3% of males, 23.9% of females, 42.7% of Whites, and 25.3%, of African Americans). Multiple logistic regression analysis showed nine factors significantly associated with readiness to change smoking behavior: male gender; a previous quit attempt; a perception of risk of lung cancer from smoking; greater desire to quit smoking; a perception that smoking bothers others; doctor advice to stop smoking at last health visit; records kept for scheduling doctor appointments; thinking that losing a pleasure would not be a problem if quit smoking; and poorer self-reported health status. These findings provide direction for developing interventions for similar low income, high risk populations. The results indicate that it may be useful to heighten awareness of the risks of smoking and to assure that smokers receive clear quit smoking messages from their providers. Women need special attention since they are less ready to quit than men. [ABSTRACT FROM AUTHOR]

Circadian clocks are intracellular systems that orchestrate metabolic processes in anticipation of sunrise and sunset by providing an internal representation of local time. Because the ~24-h metabolic rhythms they produce are important to health across diverse life forms there is growing interest in their mechanisms. However, mechanistic studies are challenging in vivo due to the complex, that is, poorly defined, milieu of live cells. Recently, we reconstituted the intact circadian clock of cyanobacteria in vitro. It oscillates autonomously and remains phase coherent for many days with a fluorescence-based readout that enables real-time observation of individual clock proteins and promoter DNA simultaneously under defined conditions without user intervention. We found that reproducibility of the reactions required strict adherence to the quality of each recombinant clock protein purified from Escherichia coli. Here, we provide protocols for preparing in vitro clock samples so that other labs can ask questions about how changing environments, like temperature, metabolites, and protein levels are reflected in the core oscillator and propagated to regulation of transcription, providing deeper mechanistic insights into clock biology., (© 2023 Wiley Periodicals LLC.)

The self-association of therapeutic antibodies can result in elevated viscosity and create problems in manufacturing and formulation, as well as limit delivery by subcutaneous injection. The high concentration viscosity of some antibodies has been reduced by variable domain mutations or by the addition of formulation excipients. In contrast, the impact of Fc mutations on antibody viscosity has been minimally explored. Here, we studied the effect of a panel of common and clinically validated Fc mutations on the viscosity of two closely related humanized IgG 1, κ antibodies, omalizumab (anti-IgE) and trastuzumab (anti-HER2). Data presented here suggest that both Fab-Fab and Fab-Fc interactions contribute to the high viscosity of omalizumab, in a four-contact model of self-association. Most strikingly, the high viscosity of omalizumab (176 cP) was reduced 10.7- and 2.2-fold by Fc modifications for half-life extension (M252Y:S254T:T256E) and aglycosylation (N297G), respectively. Related single mutations (S254T and T256E) each reduced the viscosity of omalizumab by ~6-fold. An alternative half-life extension Fc mutant (M428L:N434S) had the opposite effect in increasing the viscosity of omalizumab by 1.5-fold. The low viscosity of trastuzumab (8.6 cP) was unchanged or increased by ≤ 2-fold by the different Fc variants. Molecular dynamics simulations provided mechanistic insight into the impact of Fc mutations in modulating electrostatic and hydrophobic surface properties as well as conformational stability of the Fc. This study demonstrates that high viscosity of some IgG 1 antibodies can be mitigated by Fc mutations, and thereby offers an additional tool to help design future antibody therapeutics potentially suitable for subcutaneous delivery.

Background: Despite the fast establishment of new therapeutic agents in the management of COVID-19 and large-scale vaccination campaigns since the beginning of the SARS-CoV-2 pandemic in early 2020, severe disease courses still represent a threat, especially to patients with risk factors. This indicates the need for alternative strategies to prevent respiratory complications like acute respiratory distress syndrome (ARDS) associated with COVID-19. Aviptadil, a synthetic form of human vasoactive intestinal peptide, might be beneficial for COVID-19 patients at high risk of developing ARDS because of its ability to influence the regulation of exaggerated pro-inflammatory proteins and orchestrate the lung homeostasis. Aviptadil has recently been shown to considerably improve the prognosis of ARDS in COVID-19 when applied intravenously. An inhaled application of aviptadil has the advantages of achieving a higher concentration in the lung tissue, fast onset of activity, avoiding the hepatic first-pass metabolism, and the reduction of adverse effects. The overall objective of this project is to assess the efficacy and safety of inhaled aviptadil in patients hospitalized for COVID-19 at high risk of developing ARDS., Methods: This multicenter, placebo-controlled, double-blinded, randomized trial with 132 adult patients hospitalized for COVID-19 and at high risk for ARDS (adapted early acute lung injury score ≥ 2 points) is conducted in five public hospitals in Europe. Key exclusion criteria are mechanical ventilation at baseline, need for intensive care at baseline, and severe hemodynamic instability. Patients are randomly allocated to either inhale 67 μg aviptadil or normal saline (three times a day for 10 days), in addition to standard care, stratified by center. The primary endpoint is time from hospitalization to clinical improvement, defined as either hospital discharge, or improvement of at least two levels on the nine-level scale for clinical status suggested by the World Health Organization., Discussion: Treatment strategies for COVID-19 are still limited. In the context of upcoming new variants of SARS-CoV-2 and possible inefficacy of the available vaccines and antibody therapies, the investigation of alternative therapy options plays a crucial role in decreasing associated mortality and improving prognosis. Due to its unique immunomodulating properties also targeting the SARS-CoV-2 pathways, inhaled aviptadil may have the potential to prevent ARDS in COVID-19., Trial Registration: ClinicalTrials.gov, NCT04536350 . Registered 02 September 2020., (© 2022. The Author(s).)

As the only circadian oscillator that can be reconstituted in vitro with its constituent proteins KaiA, KaiB, and KaiC using ATP as an energy source, the cyanobacterial circadian oscillator serves as a model system for detailed mechanistic studies of day-night transitions of circadian clocks in general. The day-to-night transition occurs when KaiB forms a night-time complex with KaiC to sequester KaiA, the latter of which interacts with KaiC during the day to promote KaiC autophosphorylation. However, how KaiB forms the complex with KaiC remains poorly understood, despite the available structures of KaiB bound to hexameric KaiC. It has been postulated that KaiB-KaiC binding is regulated by inter-KaiB cooperativity. Here, using spin labeling continuous-wave electron paramagnetic resonance spectroscopy, we identified and quantified two subpopulations of KaiC-bound KaiB, corresponding to the "bulk" and "edge" KaiBC sites in stoichiometric and substoichiometric KaiB i C 6 complexes ( i = 1-5). We provide kinetic evidence to support the intermediacy of the "edge" KaiBC sites as bridges and nucleation sites between free KaiB and the "bulk" KaiBC sites. Furthermore, we show that the relative abundance of "edge" and "bulk" sites is dependent on both KaiC phosphostate and KaiA, supporting the notion of phosphorylation-state controlled inter-KaiB cooperativity. Finally, we demonstrate that the interconversion between the two subpopulations of KaiC-bound KaiB is intimately linked to the KaiC phosphorylation cycle. These findings enrich our mechanistic understanding of the cyanobacterial clock and demonstrate the utility of EPR in elucidating circadian clock mechanisms.

Circadian clocks control gene expression to provide an internal representation of local time. We report reconstitution of a complete cyanobacterial circadian clock in vitro, including the central oscillator, signal transduction pathways, downstream transcription factor, and promoter DNA. The entire system oscillates autonomously and remains phase coherent for many days with a fluorescence-based readout that enables real-time observation of each component simultaneously without user intervention. We identified the molecular basis for loss of cycling in an arrhythmic mutant and explored fundamental mechanisms of timekeeping in the cyanobacterial clock. We find that SasA, a circadian sensor histidine kinase associated with clock output, engages directly with KaiB on the KaiC hexamer to regulate period and amplitude of the central oscillator. SasA uses structural mimicry to cooperatively recruit the rare, fold-switched conformation of KaiB to the KaiC hexamer to form the nighttime repressive complex and enhance rhythmicity of the oscillator, particularly under limiting concentrations of KaiB. Thus, the expanded in vitro clock reveals previously unknown mechanisms by which the circadian system of cyanobacteria maintains the pace and rhythmicity under variable protein concentrations.

Background: Multiple myeloma (MM) in Hispanics has never been studied. We therefore sought to determine the clinical characteristics and overall survival in MM of Hispanics compared to non-Hispanic whites (NHW) and non-Hispanic blacks (NHB)., Patients and Methods: A single-center analysis of 939 patients diagnosed with MM from 2000 to 2017 with a large representation of NHB (n = 489), Hispanics (n = 281), and NHW (n = 169) was conducted to evaluate outcomes and disease characteristics. We used the Connect MM Registry, a large US multicenter prospective observational study with newly diagnosed MM patients, as a validation cohort., Results: Hispanics had a higher incidence of MM compared to NHW. The median age at presentation was 5 years younger (median, 65 years) in Hispanics compared to NHW (median, 70 years), and patients were more likely to present with renal dysfunction (estimated glomerular filtration rate < 30 mL/min). Hispanics had a higher proportion of Revised International Staging System (R-ISS) stage I disease compared to NHW and NHB (P = .03), while there was no difference in cytogenetics between Hispanics and NHB/NHW. In the multivariate analysis, only high-risk disease and response to first-line therapy significantly affected survival., Conclusion: In this first and largest analysis of MM in Hispanics, we found that Hispanics present at a younger age, have a higher incidence of renal dysfunction, and have low R-ISS stage disease at presentation. With equal access to therapy, Hispanics have survival similar to NHW/NHB., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Stochastic diffusion of a solution of fluorophores after photoselection reduces the polarization of emission, or fluorescence anisotropy. Because this randomization process is slower for larger molecules, fluorescence anisotropy is effective for measuring the kinetics of protein-binding events. Here, we describe how to use the technique to carry out real-time observations in vitro of the cyanobacterial circadian clock.

Background: There is a need for appropriate pain control in the geriatric hip fracture population to prevent diminished function, increased mortality, and opioid dependence. Multimodal pain therapy is one method for reducing pain postoperatively while also decreasing opioid use in the geriatric hip fracture patient. This study aimed to determine whether multimodal pain therapy could decrease opioid use without increasing pain scores in surgical geriatric hip fracture patients., Methods: This was a before-and-after cohort study. The hospital implemented multimodal pain control order sets with a standardized pain regimen and performed retrospective chart review pre- and postorder set implementation for analysis., Results: A total of 248 patients were enrolled in the study: 131 in the preorder set group and 117 in the postorder set group. The mean postoperative oral morphine equivalent (OME) was significantly lower in the postorder set group than in the preorder set group (45.1 mg vs. 63.4 mg, respectively, p = .03). Compared with the preorder set group, total OME and postoperative OME were decreased by 22.6% (95% confidence interval [CI] -44.9, -3.8), 1-tailed p < .01, and 53.6% (95% CI -103.4, -16.1), 1-tailed p <.01 respectively, in the postorder set group. There was not a statistically significant difference in mean pain scores at 6, 24, and 48 hr postoperatively (p = .53, .10, and .99), respectively., Conclusion: Implementing a multimodal approach to pain management may help reduce opioid use and may be a critical maneuver in averting the national opioid epidemic.

RIPK1, RIPK3, ZBP1 and TRIF, the four mammalian proteins harboring RIP homotypic interaction motif (RHIM) domains, are key components of inflammatory signaling and programmed cell death. RHIM-domain protein activation is mediated by their oligomerization; however, mechanisms that promote a return to homeostasis remain unknown. Here we show that autophagy is critical for the turnover of all RHIM-domain proteins. Macrophages lacking the autophagy gene Atg16l1 accumulated highly insoluble forms of RIPK1, RIPK3, TRIF and ZBP1. Defective autophagy enhanced necroptosis by Tumor necrosis factor (TNF) and Toll-like receptor (TLR) ligands. TNF-mediated necroptosis was mediated by RIPK1 kinase activity, whereas TLR3- or TLR4-mediated death was dependent on TRIF and RIPK3. Unexpectedly, combined deletion of Atg16l1 and Zbp1 accelerated LPS-mediated necroptosis and sepsis in mice. Thus, ZBP1 drives necroptosis in the absence of the RIPK1-RHIM, but suppresses this process when multiple RHIM-domain containing proteins accumulate. These findings identify autophagy as a central regulator of innate inflammation governed by RHIM-domain proteins., Competing Interests: JL, HP, JH, TM, MR, MX, BM, Mv, KN, AM Affiliated with Genentech. No other competing interests to declare, (© 2019, Lim et al.)