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1.
Pediatr Infect Dis J ; 2024 May 08.
Article in English | MEDLINE | ID: mdl-38717982

ABSTRACT

The effect of the Bacille Calmette-Guérin (BCG) vaccine on the immunogenicity of separately administered serogroup C meningococcal vaccine and other vaccinations was examined in 28 infants randomized to receive BCG at age ≤7 days, at 3 months or after study completion. Immunogenicity of the serogroup C meningococcal vaccine and other routine vaccines might be improved when BCG is administered in early infancy.

2.
CHEST Crit Care ; 2(1)2024 Mar.
Article in English | MEDLINE | ID: mdl-38742219

ABSTRACT

BACKGROUND: For every critically ill adult receiving invasive mechanical ventilation, clinicians must select a mode of ventilation. The mode of ventilation determines whether the ventilator directly controls the tidal volume or the inspiratory pressure. Newer hybrid modes allow clinicians to set a target tidal volume; the ventilator controls and adjusts the inspiratory pressure. A strategy of low tidal volumes and low plateau pressure improves outcomes, but the optimal mode to achieve these targets is not known. RESEARCH QUESTION: Can a cluster-randomized trial design be used to assess whether the mode of mandatory ventilation affects the number of days alive and free of invasive mechanical ventilation among critically ill adults? STUDY DESIGN AND METHODS: The Mode of Ventilation During Critical Illness (MODE) trial is a cluster-randomized, multiple-crossover pilot trial being conducted in the medical ICU at an academic center. The MODE trial compares the use of volume control, pressure control, and adaptive pressure control. The study ICU is assigned to a single-ventilator mode (volume control vs pressure control vs adaptive pressure control) for continuous mandatory ventilation during each 1-month study block. The assigned mode switches every month in a randomly generated sequence. The primary outcome is ventilator-free days to study day 28, defined as the number of days alive and free of invasive mechanical ventilation from the final receipt of mechanical ventilation to 28 days after enrollment. Enrollment began November 1, 2022, and will end on July 31, 2023. RESULTS: This manuscript describes the protocol and statistical analysis plan for the MODE trial of ventilator modes comparing volume control, pressure control, and adaptive pressure control. INTERPRETATION: Prespecifying the full statistical analysis plan prior to completion of enrollment increases rigor, reproducibility, and transparency of the trial results. CLINICAL TRIAL REGISTRATION: The trial was registered with clinicaltrials.gov on October 3, 2022, before initiation of patient enrollment on November 1, 2022 (ClinicalTrials.gov identifier: NCT05563779).

3.
Innov Aging ; 8(5): igae043, 2024.
Article in English | MEDLINE | ID: mdl-38803611

ABSTRACT

Background and Objectives: Respite, defined as time away from caregiving, is the most requested type of caregiver support. Time for Living and Caring (TLC) is a virtual coaching "app" that helps caregivers schedule and plan their respite time-use. The objectives of this analysis are: (1) to assess the efficacy of the TLC intervention on respite time-use and on caregiver well-being and (2) to identify the key features of the intervention that serve as the likely mechanism of action. Research Design and Methods: A sample of dementia caregivers (n = 163, 79% female, 84% White, 6% Hispanic, average age 62) were randomized into one of two intervention delivery methods. Intervention efficacy was evaluated using pre/post-comparisons of respite time-use and an additive "dosing" model that estimated unique parameters associated with the exposure to each specific intervention component. Results: Both immediate and delayed-attention groups reported increased respite time. They also improved in their ability to plan and perceive benefit from their respite time-use over the 16-week intervention period. At 8 weeks, the immediate group did not change in anxiety, whereas the delayed group worsened (p < .001). At 16 weeks, the groups were similar in their anxiety levels. By the 20-week follow-up period, when neither group had access to TLC, both experienced an increase in anxiety. Discussion and Implications: TLC is a promising intervention that may support caregivers' well-being, by helping them schedule and plan their respite to maximize its benefit. The provision of weekly coaching seems to be the intervention component (mechanism) associated with caregiver outcomes. Clinical Trial Registration: NCT03689179.

4.
Contemp Clin Trials ; 140: 107518, 2024 05.
Article in English | MEDLINE | ID: mdl-38554816

ABSTRACT

BACKGROUND: Recruiting participants for research studies is a critical yet challenging task. Community-engaged recruitment strategies have gained prominence as effective means to engage diverse populations and ensure the representativeness of study samples. This case study aims to investigate the cost and effectiveness of various recruitment methods in enhancing research participation. METHODS: A comparative approach was employed to assess the outcomes of five different recruitment strategies used in the Time for Living & Caring (TLC) research study. Data on recruitment success, participant demographics, and retention rates were collected and analyzed using descriptive statistics, including ANOVA and Chi-squares, to statistically compare the outcomes associated with 5 different recruitment methodologies. The recruitment methodologies included two community-engaged strategies (community partner referral and community-based recruiters), a clinical database, social media, and word-of-mouth referral. CONCLUSION: The meta-data used to build this methodological case study describe different recruitment methodologies that may be used for clinical trials. This data-driven evaluation provides examples and considerations for researchers when developing budgets and proposals for future clinical trials. The primary finding is that there are tradeoffs in terms of cost, time, labor, and ultimately the representativeness of the sample, based on the type of recruitment methodology chosen.


Subject(s)
Patient Selection , Humans , Male , Female , Social Media , Middle Aged , Cost-Benefit Analysis , Aged , Clinical Trials as Topic/methods , Clinical Trials as Topic/organization & administration , Adult , Referral and Consultation/organization & administration , Research Design
5.
J Aging Health ; : 8982643241232173, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38327121

ABSTRACT

Objectives: Using "digital inequality" as a conceptual framework, this study evaluates the feasibility and usability of a technology-delivered intervention (an "app") for Alzheimer's and related dementia family caregivers. Time for Living and Caring (TLC) is an on-line intervention that provides virtual coaching and self-administered education and resources. Methods: A sample of family caregivers (n = 163) used the tool for 16 weeks, which included completing the Computer Proficiency Questionnaire (CPQ-12) at baseline. Analyses investigate the relationship between age, CPQ scores, intervention use, appraisal, and caregiver outcomes. Results: Age was inversely associated with CPQ; however, CPQ scores did not have a significant relationship with participant's self-perceived benefits or intervention appraisal. Computer Proficiency Questionnaire scores provided insight regarding research feasibility, with lower scores associated with greater odds of discontinuing engagement. Discussion: CPQ-12 scores can be used as a screening tool to identify those who may need additional support to engage with and benefit from technology-delivered interventions.

6.
Nat Chem ; 16(2): 193-200, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37973943

ABSTRACT

Polyynes are chains of sp1 carbon atoms with alternating single and triple bonds. As they become longer, they evolve towards carbyne, the 1D allotrope of carbon, and they become increasingly unstable. It has been anticipated that long polyynes could be stabilized by supramolecular encapsulation, by threading them through macrocycles to form polyrotaxanes-but, until now, polyyne polyrotaxanes with many threaded macrocycles have been synthetically inaccessible. Here we show that masked alkynes, in which the C≡C triple bond is temporarily coordinated to cobalt, can be used to synthesize polyrotaxanes, up to the C68 [5]rotaxane with 34 contiguous triple bonds and four threaded macrocycles. This is the length regime at which the electronic properties of polyynes converge to those of carbyne. Cyclocarbons constitute a related family of molecular carbon allotropes, and cobalt-masked alkynes also provide a route to [3]catenanes and [5]catenanes built around cobalt complexes of cyclo[40]carbon and cyclo[80]carbon, respectively.

7.
Chem Soc Rev ; 52(18): 6254-6269, 2023 Sep 18.
Article in English | MEDLINE | ID: mdl-37599586

ABSTRACT

Hydrogen bonding interactions are ubiquitous across the biochemical and chemical sciences, and are of particular interest to supramolecular chemists. They have been used to assemble hydrogen bonded polymers, cages and frameworks, and are the functional motif in many host-guest systems. Single crystal X-ray diffraction studies are often used as a key support for proposed structures, although this presents challenges as hydrogen atoms interact only weakly with X-rays. In this Tutorial Review, we discuss the information that can be gleaned about hydrogen bonding interactions through crystallographic experiments, key limitations of the data, and emerging techniques to overcome these limitations.

8.
medRxiv ; 2023 Jul 24.
Article in English | MEDLINE | ID: mdl-37546787

ABSTRACT

Introduction: For every critically ill adult receiving invasive mechanical ventilation, clinicians must select a mode of ventilation. The mode of ventilation determines whether the ventilator directly controls the tidal volume or the inspiratory pressure. Newer hybrid modes allow clinicians to set a target tidal volume, for which the ventilator controls and adjusts the inspiratory pressure. A strategy of low tidal volumes and low plateau pressure improves outcomes, but the optimal mode to achieve these targets is not known. Methods and analysis: The Mode of Ventilation During Critical Illness (MODE) trial is a cluster-randomized, multiple-crossover pilot trial being conducted in the medical intensive care unit (ICU) at an academic center. The MODE trial compares the use of volume control, pressure control, and adaptive pressure control. The study ICU is assigned to a single ventilator mode (volume control versus pressure control versus adaptive pressure control) for continuous mandatory ventilation during each 1-month study block. The assigned mode switches every month in a randomly generated sequence. The primary outcome is ventilator-free days (VFDs) to study day 28, defined as the number of days alive and free of invasive mechanical ventilation from the final receipt of mechanical ventilation to 28 days after enrollment. Enrollment began November 1, 2022 and will end on July 31, 2023. Ethics and dissemination: The trial was approved by the Vanderbilt University Medical Center institutional review board (IRB# 220446). Results of this study will be submitted to a peer-reviewed journal and presented at scientific conferences. Trial registration number: The trial was registered with clinicaltrials.gov on October 3, 2022, prior to initiation of patient enrollment on November 1, 2022 (ClinicalTrials.gov identifier: NCT05563779).

9.
NPJ Vaccines ; 8(1): 100, 2023 Jul 13.
Article in English | MEDLINE | ID: mdl-37443176

ABSTRACT

The pediatric population receives the majority of vaccines globally, yet there is a paucity of studies on the transcriptional response induced by immunization in this special population. In this study, we performed a systems-level analysis of immune responses to the trivalent inactivated influenza vaccine adjuvanted with MF-59 in children (15-24 months old) and in young, healthy adults. We analyzed transcriptional responses elicited by vaccination in peripheral blood, as well as cellular and antibody responses following primary and booster vaccinations. Our analysis revealed that primary vaccination induced a persistent transcriptional signature of innate immunity; booster vaccination induced a transcriptional signature of an enhanced memory-like innate response, which was consistent with enhanced activation of myeloid cells assessed by flow cytometry. Furthermore, we identified a transcriptional signature of type 1 interferon response post-booster vaccination and at baseline that was correlated with the local reactogenicity to vaccination and defined an early signature that correlated with the hemagglutinin antibody titers. These results highlight an adaptive behavior of the innate immune system in evoking a memory-like response to secondary vaccination and define molecular correlates of reactogenicity and immunogenicity in infants.

10.
J Am Chem Soc ; 145(21): 11859-11865, 2023 May 31.
Article in English | MEDLINE | ID: mdl-37201942

ABSTRACT

Cyclic porphyrin oligomers have been studied as models for photosynthetic light-harvesting antenna complexes and as potential receptors for supramolecular chemistry. Here, we report the synthesis of unprecedented ß,ß-directly linked cyclic zinc porphyrin oligomers, the trimer (CP3) and tetramer (CP4), by Yamamoto coupling of a 2,3-dibromoporphyrin precursor. Their three-dimensional structures were confirmed by nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry, and single-crystal X-ray diffraction analyses. The minimum-energy geometries of CP3 and CP4 have propeller and saddle shapes, respectively, as calculated using density functional theory. Their different geometries result in distinct photophysical and electrochemical properties. The smaller dihedral angles between the porphyrin units in CP3, compared with CP4, result in stronger π-conjugation, splitting the ultraviolet-vis absorption bands and shifting them to longer wavelengths. Analysis of the crystallographic bond lengths indicates that the central benzene ring of the CP3 is partially aromatic [harmonic oscillator model of aromaticity (HOMA) 0.52], whereas the central cyclooctatetraene ring of the CP4 is non-aromatic (HOMA -0.02). The saddle-shaped structure of CP4 makes it a ditopic receptor for fullerenes, with affinity constants of (1.1 ± 0.4) × 105 M-1 for C70 and (2.2 ± 0.1) × 104 M-1 for C60, respectively, in toluene solution at 298 K. The formation of a 1:2 complex with C60 is confirmed by NMR titration and single-crystal X-ray diffraction.

11.
J Prev Interv Community ; 51(3): 238-253, 2023.
Article in English | MEDLINE | ID: mdl-34053412

ABSTRACT

Family members provide significant amounts of unpaid care to aging, chronically ill, and disabled persons in their homes. They often do this with little education or support and commonly report feeling overwhelmed and stressed. Providing education and support to family caregivers has demonstrated benefit on the health and well-being of the caregiver and care-receiver. However, because "caregiver" is not a reimbursable category in health care, caregiver interventions need to be delivered in a cost-efficient way. Technology-delivered and self-administered intervention models are increasingly being recommended as a pragmatic way to support aging families in our communities. This paper outlines the redevelopment of two behavioral interventions to an exclusively online delivery. This case-study analysis presents a model for community-engaged intervention research practices, which have the potential to create interventions that are more sustainable and more likely to be implemented than those designed and tested with more traditional research methodology.


Subject(s)
Caregivers , Internet-Based Intervention , Humans , Family , Chronic Disease , Community Health Services
12.
Angew Chem Int Ed Engl ; 62(3): e202213508, 2023 01 16.
Article in English | MEDLINE | ID: mdl-36226350

ABSTRACT

Sulfonylated aromatics are commonplace motifs in drugs and agrochemicals. However, methods for the direct synthesis of sulfonylated non-classical arene bioisosteres, which could improve the physicochemical properties of drug and agrochemical candidates, are limited. Here we report a solution to this challenge: a one-pot halosulfonylation of [1.1.1]propellane, [3.1.1]propellane and bicyclo[1.1.0]butanes that proceeds under practical, scalable and mild conditions. The sulfonyl halides used in this chemistry feature aryl, heteroaryl and alkyl substituents, and are conveniently generated in situ from readily available sulfinate salts and halogen atom sources. This methodology enables the synthesis of an array of pharmaceutically and agrochemically relevant halogen/sulfonyl-substituted bioisosteres and cyclobutanes, on up to multidecagram scale.


Subject(s)
Butanes , Halogens , Indicators and Reagents , Butanes/chemistry
13.
Angew Chem Int Ed Engl ; 62(5): e202214785, 2023 Jan 26.
Article in English | MEDLINE | ID: mdl-36440816

ABSTRACT

The first examples of halogen bonding (XB) heteroditopic homo[2]catenanes were prepared by discrete Na+ template-directed assembly of oligo(ethylene glycol) units derived from XB donor-containing macrocycles and acyclic bis-azide precursors, followed by a CuI -mediated azide-alkyne cycloaddition macrocyclisation reaction. Extensive 1 H NMR spectroscopic studies show the [2]catenane hosts exhibit positive cooperative ion-pair recognition behaviour, wherein XB-mediated halide recognition is enhanced by alkali metal cation pre-complexation. Notably, subtle changes in the catenanes' oligo(ethylene glycol) chain length dramatically alters their ion-binding affinity, stoichiometry, complexation mode, and conformational dynamics. Solution-phase and single-crystal X-ray diffraction studies provide evidence for competing host-separated and direct-contact ion-pair binding modes. We further demonstrate the [2]catenanes are capable of extracting solid alkali-metal halide salts into organic media.

14.
Article in English | MEDLINE | ID: mdl-38313766

ABSTRACT

Dementia caregivers are susceptible to adverse physical and mental health outcomes, given the often prolonged and challenging care and support they provide to family members with Alzheimer's Disease and Related Dementias (ADRD). This report describes a community-engaged implementation of a novel behavioral intervention - an "app" (interactive website) called TLC (Time for Living and Caring) that coaches caregivers on how to maximize the benefits associated with respite time. The rationale and features of the TLC intervention and the full research protocol used to develop and then evaluate its feasibility, acceptability, and initial efficacy are described here.

15.
Phys Chem Chem Phys ; 24(46): 28444-28456, 2022 Nov 30.
Article in English | MEDLINE | ID: mdl-36399064

ABSTRACT

X-ray characterisation methods have undoubtedly enabled cutting-edge advances in all aspects of materials research. Despite the enormous breadth of information that can be extracted from these techniques, the challenge of radiation-induced sample change and damage remains prevalent. This is largely due to the emergence of modern, high-intensity X-ray source technologies and the growing potential to carry out more complex, longer duration in situ or in operando studies. The tunability of synchrotron beamlines enables the routine application of photon energy-dependent experiments. This work explores the structural stability of [Rh(COD)Cl]2, a widely used catalyst and precursor in the chemical industry, across a range of beamline parameters that target X-ray energies of 8 keV, 15 keV, 18 keV and 25 keV, on a powder X-ray diffraction synchrotron beamline at room temperature. Structural changes are discussed with respect to absorbed X-ray dose at each experimental setting associated with the respective photon energy. In addition, the X-ray radiation hardness of the catalyst is discussed, by utilising the diffraction data collected at the different energies to determine a dose limit, which is often considered in protein crystallography and typically overlooked in small molecule crystallography. This work not only gives fundamental insight into how damage manifests in this organometallic catalyst, but will encourage careful consideration of experimental X-ray parameters before conducting diffraction on similar radiation-sensitive organometallic materials.


Subject(s)
Photons , Synchrotrons , X-Rays , Crystallography , X-Ray Diffraction
16.
Nature ; 611(7937): 721-726, 2022 11.
Article in English | MEDLINE | ID: mdl-36108675

ABSTRACT

Small-ring cage hydrocarbons are popular bioisosteres (molecular replacements) for commonly found para-substituted benzene rings in drug design1. The utility of these cage structures derives from their superior pharmacokinetic properties compared with their parent aromatics, including improved solubility and reduced susceptibility to metabolism2,3. A prime example is the bicyclo[1.1.1]pentane motif, which is mainly synthesized by ring-opening of the interbridgehead bond of the strained hydrocarbon [1.1.1]propellane with radicals or anions4. By contrast, scaffolds mimicking meta-substituted arenes are lacking because of the challenge of synthesizing saturated isosteres that accurately reproduce substituent vectors5. Here we show that bicyclo[3.1.1]heptanes (BCHeps), which are hydrocarbons for which the bridgehead substituents map precisely onto the geometry of meta-substituted benzenes, can be conveniently accessed from [3.1.1]propellane. We found that [3.1.1]propellane can be synthesized on a multigram scale, and readily undergoes a range of radical-based transformations to generate medicinally relevant carbon- and heteroatom-substituted BCHeps, including pharmaceutical analogues. Comparison of the absorption, distribution, metabolism and excretion (ADME) properties of these analogues reveals enhanced metabolic stability relative to their parent arene-containing drugs, validating the potential of this meta-arene analogue as an sp3-rich motif in drug design. Collectively, our results show that BCHeps can be prepared on useful scales using a variety of methods, offering a new surrogate for meta-substituted benzene rings for implementation in drug discovery programmes.


Subject(s)
Bridged Bicyclo Compounds , Drug Design , Heptanes , Anions/chemistry , Benzene/chemistry , Bridged Bicyclo Compounds/chemical synthesis , Bridged Bicyclo Compounds/chemistry , Drug Discovery , Heptanes/chemical synthesis , Heptanes/chemistry , Pentanes/chemical synthesis , Pentanes/chemistry , Solubility
17.
Violence Vict ; 37(3): 305-325, 2022 06 01.
Article in English | MEDLINE | ID: mdl-35654487

ABSTRACT

Using cross-national data, we analyze the effects of economic participation and opportunity, educational attainment, political empowerment, legislating reserved seats for female political candidates, and prevalence of domestic violence victimization on lethal violence against women across 39 nations. These significant factors have been studied individually with little work on their comparative, unique effects on femicide. Our paper makes such a comparison. The dependent variable, femicide by intimate partners and family members, is constructed using data from the United Nations Office on Drugs and Crime and the World Bank Group. All data are for the year 2011, a year that also corresponds to available data in the sources for our independent variables. These sources are the 2011 World Economic Forum Global Gender Gap Report, the United Nations Statistics Division, International Institute for Democracy and Electoral Assistance, and the Organisation for Economic Co-operation and Development. Our resulting sample size is 39 countries from five regions of the world: Northern and Eastern Europe (n = 7), Southern and Western Europe (n = 11), Asia and Oceania (n = 7) Africa (n = 2), and the Americas (n = 12). The unit of analysis is nation and the total number of cases of femicide by intimate partners and family members from the nations is 2,067,450,894. Our study supports backlash theory and finds in nations where educational attainment and percent women reporting domestic violence are higher, and in nations having legislated quotas for female political participation, the incidents of femicide by intimate partner and family members increase. Counter to most previous research, we find no relationship between economic participation and opportunity or political empowerment and femicide by intimate partners and family members.


Subject(s)
Crime Victims , Domestic Violence , Family , Female , Humans , Sexual Behavior , Sexual Partners , United States
18.
Qual Health Res ; 32(11): 1620-1634, 2022 09.
Article in English | MEDLINE | ID: mdl-35772971

ABSTRACT

Role conflict and strain occur when healthcare providers are required to cross boundaries, either voluntarily or involuntarily, to meet the needs of their dying patients. This research is an unobtrusive digital ethnography of a publicly accessible online forum for healthcare providers (N = 242 posts); it explores the boundaries set by families and healthcare providers, and identifies how healthcare providers navigate and which circumstances require them to sometimes cross these professional boundaries. Results indicate that patient-and-family-centered care may not be fully achieved due to the ambiguity in the expected roles played by both families and healthcare providers during patient death and dying. Grounded in data, an expanded model of the therapeutic alliance, which includes the family, is suggested.


Subject(s)
Death , Professional-Patient Relations , Health Personnel , Humans
19.
J Am Chem Soc ; 144(19): 8693-8706, 2022 May 18.
Article in English | MEDLINE | ID: mdl-35503091

ABSTRACT

The introduction of paramagnetic metal centers into a conjugated π-system is a promising approach toward engineering spintronic materials. Here, we report an investigation of two types of spin-bearing dysprosium(III) and gadolinium(III) porphyrin dimers: singly meso-meso-linked dimers with twisted conformations and planar edge-fused ß,meso,ß-linked tapes. The rare-earth spin centers sit out of the plane of the porphyrin, so that the singly linked dimers are chiral, and their enantiomers can be resolved, whereas the edge-fused tape complexes can be separated into syn and anti stereoisomers. We compare the crystal structures, UV-vis-NIR absorption spectra, electrochemistry, EPR spectroscopy, and magnetic behavior of these complexes. Low-temperature SQUID magnetometry measurements reveal intramolecular antiferromagnetic exchange coupling between the GdIII centers in the edge-fused dimers (syn isomer: J = -51 ± 2 MHz; anti isomer: J = -19 ± 3 MHz), whereas no exchange coupling is detected in the singly linked twisted complex. The phase-memory times, Tm, are in the range of 8-10 µs at 3 K, which is long enough to test quantum computational schemes using microwave pulses. Both the syn and anti Dy2 edge-fused tapes exhibit single-molecule magnetic hysteresis cycles at temperatures below 0.5 K with slow magnetization dynamics.

20.
Angew Chem Int Ed Engl ; 61(10): e202116897, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-34995402

ABSTRACT

New strategies for synthesizing polyyne polyrotaxanes are being developed as an approach to stable carbyne "insulated molecular wires". Here we report an active metal template route to polyyne [3]rotaxanes, using dicobalt carbonyl masked alkyne equivalents. We synthesized two [3]rotaxanes, both with the same C28 polyyne dumbbell component, one with a phenanthroline-based macrocycle and one using a 2,6-pyridyl cycloparaphenylene nanohoop. The thermal stabilities of the two rotaxanes were compared with that of the naked polyyne dumbbell in decalin at 80 °C, and the nanohoop rotaxane was found to be 4.5 times more stable.

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