Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 247
Filter
1.
J R Soc Interface ; 21(215): 20240038, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38835247

ABSTRACT

The health and economic impacts of infectious diseases such as COVID-19 affect all levels of a community from the individual to the governing bodies. However, the spread of an infectious disease is intricately linked to the behaviour of the people within a community since crowd behaviour affects individual human behaviour, while human behaviour affects infection spread, and infection spread affects human behaviour. Capturing these feedback loops of behaviour and infection is a well-known challenge in infectious disease modelling. Here, we investigate the interface of behavioural science theory and infectious disease modelling to explore behaviour and disease (BaD) transmission models. Specifically, we incorporate a visible protective behaviour into the susceptible-infectious-recovered-susceptible (SIRS) transmission model using the socio-psychological Health Belief Model to motivate behavioural uptake and abandonment. We characterize the mathematical thresholds for BaD emergence in the BaD SIRS model and the feasible steady states. We also explore, under different infectious disease scenarios, the effects of a fully protective behaviour on long-term disease prevalence in a community, and describe how BaD modelling can investigate non-pharmaceutical interventions that target-specific components of the Health Belief Model. This transdisciplinary BaD modelling approach may reduce the health and economic impacts of future epidemics.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , COVID-19/transmission , COVID-19/psychology , COVID-19/epidemiology , Health Belief Model , Health Behavior
2.
JACC Heart Fail ; 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38727649

ABSTRACT

BACKGROUND: In the REVIVED-BCIS2 (Revascularization for Ischemic Ventricular Dysfunction) trial, percutaneous coronary intervention (PCI) did not reduce the incidence of death or hospitalization for heart failure (HHF). OBJECTIVES: This prespecified secondary analysis investigated the effect of PCI on health status measured with the Kansas City Cardiomyopathy Questionnaire (KCCQ) combined with the primary outcome in a win ratio. METHODS: Participants with severe ischemic left ventricular dysfunction were randomized to either PCI in addition to optimal medical therapy (OMT) (PCI) or OMT alone (OMT). The primary outcome was a hierarchical composite of all-cause death, HHF, and KCCQ-Overall Summary Score (OSS) at 24 months analyzed using the unmatched win ratio. The key secondary endpoint was a KCCQ-OSS responder analysis. RESULTS: A total of 347 participants were randomized to PCI and 353 to OMT. Median age was 70.0 years (Q1-Q3: 63.3-76.1 years). Mean left ventricular ejection fraction was 27.0 ± 6.7%. PCI did not improve the primary endpoint (win ratio for PCI vs OMT: 1.05; 95% CI: 0.88-1.26; P = 0.58). PCI resulted in more KCCQ-OSS responders than OMT at 6 months (54.1% vs 40.7%; OR: 1.96; 95% CI: 1.41-2.71; P < 0.001) and fewer deteriorators (25.2% vs 31.4%; OR: 0.69; 95% CI: 0.47-1.00; P = 0.048). PCI did not impact KCCQ-OSS responders or deteriorators at 12 or 24 months. CONCLUSIONS: PCI did not improve the hierarchical composite of death, HHF, and health status at 2 years. PCI improved KCCQ-OSS at 6 months, but this benefit was not sustained to 1- or 2-year follow-up. (Revacularization for Ischemic Ventricular Dysfunction [REVIVED-BCIS2]; NCT01920048).

3.
Emerg Med Australas ; 2024 May 27.
Article in English | MEDLINE | ID: mdl-38800891

ABSTRACT

OBJECTIVE: To examine gender differences in Australian football (AF)-related concussion presentations to EDs in regional Australia. METHODS: A prospective observational study of patients presenting to 1 of the 10 EDs in Western Victoria, Australia, with an AF-related concussion was conducted. Patients were part of a larger study investigating AF injuries over a complete AF season, including pre-season training and practice matches. Information regarding concussion injuries was extracted from patient medical records, including clinical features, concurrent injuries, mechanism and context of injury. Female and male data were compared with chi-squared and Fisher's exact tests. P < 0.05 was considered significant. RESULTS: From the original cohort of 1635 patients with AF-related injuries (242 female and 1393 male), 231 (14.1%) patients were diagnosed with concussion. Thirty-eight (15.7%) females had concussions versus 193 (13.9%) males (P > 0.05). Females over the age of 16 were more likely to be concussed than males in the same age range (females n = 26, 68.4% vs males n = 94, 48.7%; P = 0.026). Neurosurgically significant head injury was rare (one case). Similar rates of concurrent injury were found between females 15 (39.5%) and males 64 (33.2%), with neck injury the single most common in 24 (10.3%) concussions. Sixty-nine patients (29%) were admitted for observation or to await the results of scans. The majority of concussions occurred in match play (87.9%). Females were more likely injured in contested ball situations (63.2% vs 37.3%; P < 0.05). CONCLUSION: Concussion rates for community-level AF presentations to regional EDs were similar between genders. Serious head injury was rare, although hospital admission for observation was common. Concurrent injuries were common, with associated neck injury most often identified. Match play accounted for the majority of head injuries.

4.
Emerg Med Australas ; 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38649794

ABSTRACT

OBJECTIVE: To determine (i) the prevalence of overweight and obesity among children presenting to all EDs in a large regional Australian city and (ii) whether age, sex, socioeconomic status (SES) or hospital setting (public vs private) were associated with overweight and obesity. METHODS: This prospective observational study included children aged ≥2 and <18 years who presented to any of three EDs over an 18 month period who had their height and weight measured. Age, sex and residential postcode were collected. Weight category was determined by sex and age standardised body mass index (BMI) z-score. Weight category was assessed by sex, age, SES and hospital setting with chi-squared tests, and ordinal logistic regression with cluster sandwich error estimators. Results were reported using odds ratios (OR) with 95% confidence intervals (CI). RESULTS: Data were collected for 3827 children, of which 11.6% were obese and 19.8% overweight. The prevalence of obesity was highest in those aged 8-14 years and in those from lower SES postcodes. The likelihood of obesity was higher in the public than the private hospitals (OR 0.66, 95% CI 0.51-0.86), whereas the likelihood of overweight was similar (OR 1.00, 95% CI 0.83-1.22). CONCLUSIONS: Almost one-third of children who presented to EDs were overweight or obese. Obesity was particularly high in those aged 8-14 years and those from lower SES postcodes. In the evolving obesity crisis, the high proportion of children presenting to EDs above a healthy weight might represent an opportunity for EDs to identify and refer children for body weight and lifestyle management.

5.
Perfusion ; 39(1_suppl): 13S-22S, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38651575

ABSTRACT

INTRODUCTION: Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) improves end-organ perfusion in cardiogenic shock but may increase afterload, which can limit cardiac recovery. Left ventricular (LV) unloading strategies may aid cardiac recovery and prevent complications of increased afterload. However, there is no consensus on when and which unloading strategy should be used. METHODS: An online survey was distributed worldwide via the EuroELSO newsletter mailing list to describe contemporary international practice and evaluate heterogeneity in strategies for LV unloading. RESULTS: Of 192 respondents from 43 countries, 53% routinely use mechanical LV unloading, to promote ventricular recovery and/or to prevent complications. Of those that do not routinely unload, 65% cited risk of complications as the reason. The most common indications for unplanned unloading were reduced arterial line pulsatility (68%), pulmonary edema (64%) and LV dilatation (50%). An intra-aortic balloon pump was the most frequently used device for unloading followed by percutaneous left ventricular assist devices. Echocardiography was the most frequently used method to monitor the response to unloading. CONCLUSIONS: Significant variation exists with respect to international practice of ventricular unloading. Further research is required that compares the efficacy of different unloading strategies and a randomized comparison of routine mechanical unloading versus unplanned unloading.


Subject(s)
Extracorporeal Membrane Oxygenation , Humans , Extracorporeal Membrane Oxygenation/methods , Surveys and Questionnaires , Female , Male , Shock, Cardiogenic/therapy , Shock, Cardiogenic/physiopathology , Heart-Assist Devices
6.
Pest Manag Sci ; 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38527910

ABSTRACT

Transgenic, dicamba-resistant soybean and cotton were developed to enable farmers to combat weeds that had evolved resistance to the herbicide glyphosate. The dramatic increases in dicamba use these crops facilitated have led to serious problems, including the evolution of dicamba-resistant weeds and widespread damage to susceptible crops and farming communities. Disturbingly, this pattern of dicamba use has unfolded while the total herbicide applied to soybean has nearly doubled since 2006. Without substantive changes to agricultural policy and decision making, the next 'silver-bullet' agrotechnology will likely be no more than another step on the transgene-facilitated herbicide treadmill. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

7.
J Pediatr Gastroenterol Nutr ; 78(5): 1155-1160, 2024 May.
Article in English | MEDLINE | ID: mdl-38482943

ABSTRACT

Unsedated transnasal endoscopy (TNE) is an alternative method of examining the esophageal mucosa in pediatric patients with eosinophilic esophagitis (EoE), reducing cost, time, and risk associated with frequent surveillance esophagogastroduodenoscopies (EGD). Adequacy of transnasal esophageal biopsies for the evaluation of eosinophilic esophagitis histologic scoring system (EoEHSS) has not yet been evaluated. We compared procedure times, endoscopic findings, and EoEHSS scoring for EoE patients undergoing TNE versus standard EGD. Sixty-six TNE patients and 132 EGD controls matched for age (mean age 14.0 years) and disease status (29.3% active) were included. Compared to patients undergoing standard EGD, patients undergoing TNE spent 1.94 h less in the GI suite (p < 0.0001), with comparable occurrence rates of all visual endoscopic findings and most EoEHSS components. TNE serves as a useful tool for long-term disease surveillance, and consideration should be given to its use in clinical trials for EoE.


Subject(s)
Eosinophilic Esophagitis , Humans , Eosinophilic Esophagitis/diagnosis , Eosinophilic Esophagitis/pathology , Male , Adolescent , Female , Child , Endoscopy, Digestive System/methods , Biopsy/methods , Esophagoscopy/methods , Esophagus/pathology , Esophagus/diagnostic imaging , Case-Control Studies
8.
Circ Cardiovasc Interv ; 17(3): e013367, 2024 03.
Article in English | MEDLINE | ID: mdl-38410944

ABSTRACT

INTRODUCTION: Percutaneous coronary intervention for complex coronary disease is associated with a high risk of cardiogenic shock. This can cause harm and limit the quality of revascularization achieved, especially when left ventricular function is impaired at the outset. Elective percutaneous left ventricular unloading is increasingly used to mitigate adverse events in patients undergoing high-risk percutaneous coronary intervention, but this strategy has fiscal and clinical costs and is not supported by robust evidence. METHODS: CHIP-BCIS3 (Controlled Trial of High-Risk Coronary Intervention With Percutaneous Left Ventricular Unloading) is a prospective, multicenter, open-label randomized controlled trial that aims to determine whether a strategy of elective percutaneous left ventricular unloading is superior to standard care (no planned mechanical circulatory support) in patients undergoing nonemergent high-risk percutaneous coronary intervention. Patients are eligible for recruitment if they have severe left ventricular systolic dysfunction, extensive coronary artery disease, and are due to undergo complex percutaneous coronary intervention (to the left main stem with calcium modification or to a chronic total occlusion with a retrograde approach). Cardiogenic shock and acute ST-segment-elevation myocardial infarction are exclusions. The primary outcome is a hierarchical composite of all-cause death, stroke, spontaneous myocardial infarction, cardiovascular hospitalization, and periprocedural myocardial infarction, analyzed using the win ratio. Secondary outcomes include completeness of revascularization, major bleeding, vascular complications, health economic analyses, and health-related quality of life. A sample size of 250 patients will have in excess of 80% power to detect a hazard ratio of 0.62 at a minimum of 12 months, assuming 150 patients experience an event across all follow-up. CONCLUSIONS: To date, 169 patients have been recruited from 21 National Health Service hospitals in the United Kingdom, with recruitment expected to complete in 2024. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT05003817.


Subject(s)
Coronary Artery Disease , Myocardial Infarction , Percutaneous Coronary Intervention , Humans , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/therapy , Myocardial Infarction/etiology , Percutaneous Coronary Intervention/adverse effects , Prospective Studies , Quality of Life , Shock, Cardiogenic/diagnosis , Shock, Cardiogenic/therapy , Shock, Cardiogenic/etiology , State Medicine , Treatment Outcome , Randomized Controlled Trials as Topic , Multicenter Studies as Topic
9.
J Chem Phys ; 160(6)2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38341780

ABSTRACT

Understanding water dynamics at charged interfaces is of great importance in various fields, such as catalysis, biomedical processes, and solar cell materials. In this study, we implemented molecular dynamics simulations of a system of pure water interfaced with Au electrodes, on one side of which 4-mercaptobenzonitrile (4-MBN) molecules are adsorbed. We calculated time correlation functions of various dynamic quantities, such as the hydrogen bond status of the N atom of the adsorbed 4-MBN molecules, the rotational motion of the water OH bond, hydrogen bonds between 4-MBN and water, and hydrogen bonds between water molecules in the interface region. Using the Luzar-Chandler model, we analyzed the hydrogen bond dynamics between a 4-MBN and a water molecule. The dynamic quantities we calculated can be divided into two categories: those related to the collective behavior of interfacial water molecules and the H-bond interaction between a water molecule and the CN group of 4-MBN. We found that these two categories of dynamic quantities exhibit opposite trends in response to applied potentials on the Au electrode. We anticipate that the present work will help improve our understanding of the interfacial dynamics of water in various electrolyte systems.

10.
Sci Data ; 11(1): 200, 2024 Feb 13.
Article in English | MEDLINE | ID: mdl-38351049

ABSTRACT

Winter cover crop performance metrics (i.e., vegetative biomass quantity and quality) affect ecosystem services provisions, but they vary widely due to differences in agronomic practices, soil properties, and climate. Cereal rye (Secale cereale) is the most common winter cover crop in the United States due to its winter hardiness, low seed cost, and high biomass production. We compiled data on cereal rye winter cover crop performance metrics, agronomic practices, and soil properties across the eastern half of the United States. The dataset includes a total of 5,695 cereal rye biomass observations across 208 site-years between 2001-2022 and encompasses a wide range of agronomic, soils, and climate conditions. Cereal rye biomass values had a mean of 3,428 kg ha-1, a median of 2,458 kg ha-1, and a standard deviation of 3,163 kg ha-1. The data can be used for empirical analyses, to calibrate, validate, and evaluate process-based models, and to develop decision support tools for management and policy decisions.


Subject(s)
Edible Grain , Secale , Agriculture , Ecosystem , Edible Grain/growth & development , Seasons , Secale/growth & development , Soil , United States
11.
Article in English | MEDLINE | ID: mdl-38415869

ABSTRACT

OBJECTIVE: Currently, the relationship between parathyroidectomy and objective neuropsychiatric outcomes are not clearly defined. The purpose of this study is to perform the first ever Meta-analysis of preoperative and postoperative PHQ-9 and GAD-7 scores in patients with primary hyperparathyroidism undergoing parathyroidectomy with the goal of identifying a specific psychometric score that could be used as an indication for surgical intervention. DATA SOURCES: A comprehensive search of the literature was performed using PubMed, Embase, PsycINFO, Web of Science, and Ovid All EBM Reviews. REVIEW METHODS: Studies met inclusion criteria if they evaluated preoperative and postoperative PHQ-9 and/or GAD-7 scores in patients with primary hyperparathyroidism undergoing parathyroidectomy. Random effects Meta-analyses were used to analyze the compiled data. RESULTS: The literature search returned 1433 articles for initial review of which 6 (1105 participants) met criteria for inclusion and Meta-analysis. Meta-analysis revealed that primary hyperparathyroidism patients had significantly higher presurgical PHQ-9 scores when compared to control groups. Additionally, patients experienced a statistically significant and sustained decrease in PHQ-9 scores following parathyroidectomy. Notably, there was a dramatic decrease in the percentage of patients with PHQ-9 scores ≥10 (considered clinically significant for depression) following parathyroidectomy. CONCLUSION: Patients with primary hyperparathyroidism experience a statistically significant and sustained improvement in PHQ-9 scores following parathyroidectomy. Additionally, symptoms of anxiety and suicidal ideation appear to decrease after parathyroidectomy. We propose that a PHQ-9 score ≥10 could potentially be used as an indication for parathyroidectomy in patients with asymptomatic primary hyperparathyroidism.

12.
J Am Chem Soc ; 146(2): 1543-1553, 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38181505

ABSTRACT

Water inside biological ion channels regulates the key properties of these proteins, such as selectivity, ion conductance, and gating. In this article, we measure the picosecond spectral diffusion of amide I vibrations of an isotope-labeled KcsA potassium channel using two-dimensional infrared (2D IR) spectroscopy. By combining waiting time (100-2000 fs) 2D IR measurements of the KcsA channel including 13C18O isotope-labeled Val76 and Gly77 residues with molecular dynamics simulations, we elucidated the site-specific dynamics of water and K+ ions inside the selectivity filter of KcsA. We observe inhomogeneous 2D line shapes with extremely slow spectral diffusion. Our simulations quantitatively reproduce the experiments and show that water is the only component with any appreciable dynamics, whereas K+ ions and the protein are essentially static on a picosecond timescale. By analyzing simulated and experimental vibrational frequencies, we find that water in the selectivity filter can be oriented to form hydrogen bonds with adjacent or nonadjacent carbonyl groups with the reorientation timescales being three times slower and comparable to that of water molecules in liquid, respectively. Water molecules can reside in the cavity sufficiently far from carbonyls and behave essentially like "free" gas-phase-like water with fast reorientation times. Remarkably, no interconversion between these configurations was observed on a picosecond timescale. These dynamics are in stark contrast with liquid water, which remains highly dynamic even in the presence of ions at high concentrations.

13.
Mil Med ; 189(3-4): 475-480, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-36892849

ABSTRACT

INTRODUCTION: Because inadequate sleep impairs mission performance, the U.S. Army regards sleep as a core pillar of soldier readiness. There is an increasing incidence of obstructive sleep apnea (OSA) among active duty (AD) service members, which is a disqualifying condition for initial enlistment. Moreover, a new diagnosis of OSA in the AD population often prompts a medical evaluation board, and if symptomatic OSA proves refractory to treatment, this may result in medical retirement. Hypoglossal nerve stimulator implantation (HNSI) is a newer implantable treatment option, which requires minimal ancillary equipment to function and may provide a useful treatment modality to support AD service members while maintaining readiness in appropriate candidates. Because of a perception among AD service members that HNSI results in mandatory medical discharge, we aimed to evaluate the impact of HNSI on military career progression, maintenance of deployment readiness, and patient satisfaction. METHODS: The Department of Research Programs at the Walter Reed National Military Medical Center provided institutional review board approval for this project. This is a retrospective, observational study and telephonic survey of AD HNSI recipients. Military service information, demographics, surgical data, and postoperative sleep study results were collected from each patient.Additional survey questions assessed each service member's experience with the device. RESULTS: Fifteen AD service members who underwent HNSI between 2016 and 2021 were identified. Thirteen subjects completed the survey. The mean age was 44.8 years (range 33-61), and all were men. Six subjects (46%) were officers. All subjects maintained AD status following HNSI yielding 14.5 person-years of continued AD service with the implant. One subject underwent formal assessment for medical retention. One subject transferred from a combat role to a support role. Six subjects have since voluntarily separated from AD service following HNSI. These subjects spent an average of 360 (37-1,039) days on AD service. Seven subjects currently remain on AD and have served for an average of 441 (243-882) days. Two subjects deployed following HNSI. Two subjects felt that HSNI negatively affected their career. Ten subjects would recommend HSNI to other AD personnel. Following HNSI, of the eight subjects with postoperative sleep study data, five achieved surgical success defined as >50% reduction of apnea-hypopnea index and absolute apnea-hypopnea index value of <20. CONCLUSIONS: Hypoglossal nerve stimulator implantation for AD service members offers an effective treatment modality for OSA, which generally allows for the ability to maintain AD status, however: The impact on deployment readiness should be seriously considered and tailored to each service member based on their unique duties before implantation. Seventy-seven percent of HNSI patients would recommend it to other AD service members suffering from OSA.


Subject(s)
Military Personnel , Sleep Apnea, Obstructive , Male , Humans , Adult , Middle Aged , Female , Hypoglossal Nerve , Sleep Apnea, Obstructive/therapy , Sleep Apnea, Obstructive/epidemiology , Retrospective Studies , Personal Satisfaction
14.
Eur J Heart Fail ; 26(2): 302-310, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38152863

ABSTRACT

AIM: Heart failure with preserved ejection fraction (HFpEF) remains under-diagnosed in clinical practice despite accounting for nearly half of all heart failure (HF) cases. Accurate and timely diagnosis of HFpEF is crucial for proper patient management and treatment. In this study, we explored the potential of natural language processing (NLP) to improve the detection and diagnosis of HFpEF according to the European Society of Cardiology (ESC) diagnostic criteria. METHODS AND RESULTS: In a retrospective cohort study, we used an NLP pipeline applied to the electronic health record (EHR) to identify patients with a clinical diagnosis of HF between 2010 and 2022. We collected demographic, clinical, echocardiographic and outcome data from the EHR. Patients were categorized according to the left ventricular ejection fraction (LVEF). Those with LVEF ≥50% were further categorized based on whether they had a clinician-assigned diagnosis of HFpEF and if not, whether they met the ESC diagnostic criteria. Results were validated in a second, independent centre. We identified 8606 patients with HF. Of 3727 consecutive patients with HF and LVEF ≥50% on echocardiogram, only 8.3% had a clinician-assigned diagnosis of HFpEF, while 75.4% met ESC criteria but did not have a formal diagnosis of HFpEF. Patients with confirmed HFpEF were hospitalized more frequently; however the ESC criteria group had a higher 5-year mortality, despite being less comorbid and experiencing fewer acute cardiovascular events. CONCLUSIONS: This study demonstrates that patients with undiagnosed HFpEF are an at-risk group with high mortality. It is possible to use NLP methods to identify likely HFpEF patients from EHR data who would likely then benefit from expert clinical review and complement the use of diagnostic algorithms.


Subject(s)
Heart Failure , Humans , Stroke Volume , Ventricular Function, Left , Artificial Intelligence , Retrospective Studies , Prognosis
15.
Proc Natl Acad Sci U S A ; 120(52): e2314998120, 2023 Dec 26.
Article in English | MEDLINE | ID: mdl-38127983

ABSTRACT

We report the hydrogen-bonding dynamics of water to a nitrile-functionalized and plasmonic electrode surface as a function of applied voltage. The surface-enhanced two-dimensional infrared spectra exhibit hydrogen-bonded and non-hydrogen-bonded nitrile features in similar proportions, plus cross peaks between the two. Isotopic dilution experiments show that the cross peaks arise predominantly from chemical exchange between hydrogen-bonded and non-hydrogen-bonded nitriles. The chemical exchange rate depends upon voltage, with the hydrogen bond of the water to the nitriles breaking 2 to 3 times slower (>63 vs. 25 ps) under a positive as compared to a negative potential. Spectral diffusion created by hydrogen-bond fluctuations occurs on a ~1 ps timescale and is moderately potential-dependent. Timescales from molecular dynamics simulations agree qualitatively with the experiment and show that a negative voltage causes a small net displacement of water away from the surface. These results show that the voltage applied to an electrode can alter the timescales of solvent motion at its interface, which has implications for electrochemically driven reactions.

16.
bioRxiv ; 2023 Nov 17.
Article in English | MEDLINE | ID: mdl-38014355

ABSTRACT

Water inside biological ion channels regulates the key properties of these proteins such as selectivity, ion conductance, and gating. In this Article we measure the picosecond spectral diffusion of amide I vibrations of an isotope labeled KcsA potassium channel using two-dimensional infrared (2D IR) spectroscopy. By combining waiting time (100 - 2000 fs) 2D IR measurements of the KcsA channel including 13C18O isotope labeled Val76 and Gly77 residues with molecular dynamics simulations, we elucidated the site-specific dynamics of water and K+ ions inside the selectivity filter of KcsA. We observe inhomogeneous 2D lineshapes with extremely slow spectral diffusion. Our simulations quantitatively reproduce the experiments and show that water is the only component with any appreciable dynamics, whereas K+ ions and the protein are essentially static on a picosecond timescale. By analyzing simulated and experimental vibrational frequencies, we find that water in the selectivity filter can be oriented to form hydrogen bonds with adjacent, or non-adjacent carbonyl groups with the reorientation timescales being three times slower and comparable to that of water molecules in liquid, respectively. Water molecules can reside in the cavity sufficiently far from carbonyls and behave essentially like "free" gas-phase-like water with fast reorientation times. Remarkably, no interconversion between these configurations were observed on a picosecond timescale. These dynamics are in stark contrast with liquid water that remains highly dynamic even in the presence of ions at high concentrations.

17.
Proc Biol Sci ; 290(2011): 20231453, 2023 Nov 29.
Article in English | MEDLINE | ID: mdl-38018107

ABSTRACT

Soil legacy influences plant interactions with antagonists and below-ground mutualists. Plant-antagonist interactions can jeopardize plant-pollinator interactions, while soil mutualists can enhance plant-pollinator interactions. This suggests that soil legacy, either directly or mediated through plant symbionts, affects pollinators. Despite the importance of pollinators to natural and managed ecosystems, information on how soil legacy affects plant-pollinator interactions is limited. We assessed effects of soil management legacy (organic versus conventional) on floral rewards and plant interactions with wild pollinators, herbivores, beneficial fungi and pathogens. We used an observational dataset and structural equation models to evaluate hypothesized relationships between soil and pollinators, then tested observed correlations in a manipulative experiment. Organic legacy increased mycorrhizal fungal colonization and improved resistance to powdery mildew, which promoted pollinator visitation. Further, soil legacy and powdery mildew independently and interactively impacted floral traits and floral reward nutrients, which are important to pollinators. Our results indicate that pollination could be an overlooked consequence of soil legacy and suggests opportunity to develop long-term soil management plans that benefit pollinators and pollination.


Subject(s)
Ecosystem , Mycorrhizae , Soil , Flowers , Agriculture , Pollination , Crops, Agricultural
18.
JAMA Cardiol ; 8(12): 1154-1161, 2023 12 01.
Article in English | MEDLINE | ID: mdl-37878295

ABSTRACT

Importance: In the Revascularization for Ischemic Ventricular Dysfunction (REVIVED-BCIS2) trial, percutaneous coronary intervention (PCI) did not improve outcomes for patients with ischemic left ventricular dysfunction. Whether myocardial viability testing had prognostic utility for these patients or identified a subpopulation who may benefit from PCI remained unclear. Objective: To determine the effect of the extent of viable and nonviable myocardium on the effectiveness of PCI, prognosis, and improvement in left ventricular function. Design, Setting, and Participants: Prospective open-label randomized clinical trial recruiting between August 28, 2013, and March 19, 2020, with a median follow-up of 3.4 years (IQR, 2.3-5.0 years). A total of 40 secondary and tertiary care centers in the United Kingdom were included. Of 700 randomly assigned patients, 610 with left ventricular ejection fraction less than or equal to 35%, extensive coronary artery disease, and evidence of viability in at least 4 myocardial segments that were dysfunctional at rest and who underwent blinded core laboratory viability characterization were included. Data analysis was conducted from March 31, 2022, to May 1, 2023. Intervention: Percutaneous coronary intervention in addition to optimal medical therapy. Main Outcomes and Measures: Blinded core laboratory analysis was performed of cardiac magnetic resonance imaging scans and dobutamine stress echocardiograms to quantify the extent of viable and nonviable myocardium, expressed as an absolute percentage of left ventricular mass. The primary outcome of this subgroup analysis was the composite of all-cause death or hospitalization for heart failure. Secondary outcomes were all-cause death, cardiovascular death, hospitalization for heart failure, and improved left ventricular function at 6 months. Results: The mean (SD) age of the participants was 69.3 (9.0) years. In the PCI group, 258 (87%) were male, and in the optimal medical therapy group, 277 (88%) were male. The primary outcome occurred in 107 of 295 participants assigned to PCI and 114 of 315 participants assigned to optimal medical therapy alone. There was no interaction between the extent of viable or nonviable myocardium and the effect of PCI on the primary or any secondary outcome. Across the study population, the extent of viable myocardium was not associated with the primary outcome (hazard ratio per 10% increase, 0.98; 95% CI, 0.93-1.04) or any secondary outcome. The extent of nonviable myocardium was associated with the primary outcome (hazard ratio, 1.07; 95% CI, 1.00-1.15), all-cause death, cardiovascular death, and improvement in left ventricular function. Conclusions and Relevance: This study found that viability testing does not identify patients with ischemic cardiomyopathy who benefit from PCI. The extent of nonviable myocardium, but not the extent of viable myocardium, is associated with event-free survival and likelihood of improvement of left ventricular function. Trial Registration: ClinicalTrials.gov Identifier: NCT01920048.


Subject(s)
Heart Failure , Percutaneous Coronary Intervention , Ventricular Dysfunction, Left , Humans , Male , Aged , Female , Stroke Volume , Prospective Studies , Percutaneous Coronary Intervention/adverse effects , Follow-Up Studies , Ventricular Function, Left , Heart Failure/therapy , Heart Failure/complications , Ventricular Dysfunction, Left/complications
19.
Sci Rep ; 13(1): 17323, 2023 10 13.
Article in English | MEDLINE | ID: mdl-37833350

ABSTRACT

Cover crops are plants grown to provide regulating, supporting, and cultural ecosystem services in managed environments. In agricultural systems, weed suppression services from cover crops can be an important tool to promote sustainability as reliance on herbicides and tillage for weed management has caused pollution, biodiversity loss, and human health issues. However, to effectively use weed suppression services from cover crops, farmers must carefully select species that fit within their rotations and suppress their problematic weeds. Understanding how the relatedness between cover crops and weeds affects their interactions will help farmers select cover crops for targeted weed management. The phylogenetic distance between species reflects their relatedness and was studied through a series of field experiments that compared weed suppression in winter and summer cover crops with tilled controls. This study demonstrates that cover crops can reduce up to 99% of weed biomass and alter weed community structure by suppressing phylogenetically related weed species. Results also suggest that cover crop planting season can influence weed community structure since only overwintering treatments affected the phylogenetic distance of weed communities. In an applied context, these results help develop cover crop-based weed management systems, demonstrating that problematic weeds can be managed by selecting phylogenetically related cover crop species. More broadly, this study provides a framework for evaluating weed communities through a phylogenetic perspective, which provides new insight into plant interactions in agriculture.


Subject(s)
Ecosystem , Herbicides , Humans , Phylogeny , Agriculture/methods , Plant Weeds , Herbicides/pharmacology , Crops, Agricultural , Weed Control/methods
20.
Sci Rep ; 13(1): 17386, 2023 10 13.
Article in English | MEDLINE | ID: mdl-37833370

ABSTRACT

For neurological disorders and diseases, functional and anatomical connectomes of the human brain can be used to better inform targeted interventions and treatment strategies. Functional magnetic resonance imaging (fMRI) is a non-invasive neuroimaging technique that captures spatio-temporal brain function through change in blood-oxygen-level-dependent (BOLD) signals over time. FMRI can be used to study the functional connectome through the functional connectivity matrix; that is, Pearson's correlation matrix between time series from the regions of interest of an fMRI image. One approach to analysing functional connectivity is using partial least squares (PLS), a multivariate regression technique designed for high-dimensional predictor data. However, analysing functional connectivity with PLS ignores a key property of the functional connectivity matrix; namely, these matrices are positive definite. To account for this, we introduce a generalisation of PLS to Riemannian manifolds, called R-PLS, and apply it to symmetric positive definite matrices with the affine invariant geometry. We apply R-PLS to two functional imaging datasets: COBRE, which investigates functional differences between schizophrenic patients and healthy controls, and; ABIDE, which compares people with autism spectrum disorder and neurotypical controls. Using the variable importance in the projection statistic on the results of R-PLS, we identify key functional connections in each dataset that are well represented in the literature. Given the generality of R-PLS, this method has the potential to investigate new functional connectomes in the brain, and with future application to structural data can open up further avenues of research in multi-modal imaging analysis.


Subject(s)
Autism Spectrum Disorder , Connectome , Humans , Connectome/methods , Least-Squares Analysis , Brain/diagnostic imaging , Magnetic Resonance Imaging/methods
SELECTION OF CITATIONS
SEARCH DETAIL
...