Accelerated Screening of Protein-Ligand Interactions via Parallel T2-Weighted 19F-MRI.

In drug discovery, ligands are sought that modulate the (mal-)function of medicinally relevant target proteins. In order to develop new drugs, typically a multitude of potential ligands are initially screened for binding and subsequently characterized for their affinity. Nuclear magnetic resonance (NMR) is a well-established and highly sensitive technology for characterizing such interactions. However, it has limited throughput, because only one sample can be measured at a time. In contrast, magnetic resonance imaging (MRI) is inherently parallel and MR parameters can conveniently be encoded in its images, potentially offering increased sample throughput. We explore this application using a custom-built 9-fold sample holder and a 19F-MRI coil. With this setup, we show that ligand binding can be detected by T2-weighted 19F-MRI using 4-(trifluoromethyl)benzamidine (TFBA) and trypsin as the reporter ligand and target protein, respectively. Furthermore, we demonstrate that the affinity of nonfluorinated ligands can be determined in a competition format by monitoring the dose-dependent displacement of TFBA. By comparing 19F-T2-weighted MR images of TFBA in the presence of different benzamidine (BA) concentrations-all recorded in parallel-the affinity of BA could be derived. Therefore, this approach promises parallel characterization of protein-ligand interactions and increased throughput of biochemical assays, with potential for increased sensitivity when combined with hyperpolarization techniques.

Enhanced Predictability of Urea Crystallization by an Optimized Laser Repetition Rate.

Laser-induced crystallization is a novel alternative to classical methods for crystallizing organic molecules but requires a judicious choice of experimental parameters for the onset of crystallization to be predictable. This study investigated the impact of the laser repetition rate on the time delay from the start of the pulsed laser illumination to the initiation of crystallization, the so-called induction time. A supersaturated urea solution was irradiated with near-infrared (λ = 1030 nm) laser pulses of pulse duration τ = 5 ps at a pulse energy of approximately E = 340 µJ while varying the repetition rate from 10 to 20,000 Hz. The optimal rate discovered ranged from 500 Hz to 1 kHz, quantified by the measured induction time (median 2-5 s) and the mean probability of inducing a successful crystallization event (5 × 10-2%). For higher repetition rates (5-20 kHz), the mean probability dropped to 3 × 10-3%. The reduced efficiency at high repetition rates is likely due to an interaction between an existing thermocavitation bubble and subsequent pulses. These results suggest that an optimized pulse repetition rate can be a means to gain further control over the laser-induced crystallization process.

Community pharmacists' naloxone counseling: A theory-informed qualitative study.

BACKGROUND: Opioid-related overdose (ORO) deaths have reached a record high in the United States. Naloxone is an opioid antagonist that can rapidly reverse an opioid overdose. Pharmacists are in an ideal position to provide naloxone and related counseling, given their accessibility and expertise. However, minimal research is available on community pharmacists' naloxone counseling. OBJECTIVES: The aim of this study was to investigate Georgia community pharmacists' naloxone counseling as well as explore their attitudes, subjective norms, and perceived behavioral control toward counseling. METHODS: Semi-structured telephone interviews were conducted to elicit pharmacists' beliefs and practices regarding naloxone counseling. The interviews were guided by open-ended questions based on the theory of planned behavior (TPB). Thematic analysis was performed to identify the modal salient beliefs expressed by the pharmacists. The Consolidated Criteria for Reporting Qualitative Research was used to report the study findings. RESULTS: A total of 12 community pharmacists participated. Pharmacists held mixed attitudes toward naloxone counseling. While they recognized it as a vital part of their profession to prevent ORO deaths, they also expressed concerns about offending patients. Regarding normative beliefs, pharmacists identified several groups, including regulatory agencies (e.g., Board of Pharmacy, CDC), managers, news/media, patients, and doctors, influencing their provision of naloxone counseling. Facilitators to counseling included receiving naloxone training and having access to counseling guidelines and resources. Reimbursement issues, high costs of naloxone, and lack of patient awareness were the most commonly cited barriers. Pharmacists reported participating in counseling and providing information on identifying signs of opioid overdose and administering naloxone. CONCLUSIONS: The TPB is a useful framework for understanding community pharmacists' beliefs and practices regarding naloxone counseling. Capitalizing on facilitators and targeting barriers related to pharmacists' reimbursement issues, high costs of naloxone, and increasing patients' awareness of naloxone use and benefits may enhance pharmacists' naloxone counseling.

Mapping Health Disparities in 11 High-Income Nations.

Importance: Health care delivery faces a myriad of challenges globally with well-documented health inequities based on geographic location. Yet, researchers and policy makers have a limited understanding of the frequency of geographic health disparities. Objective: To describe geographic health disparities in 11 high-income countries. Design, Setting, and Participants: In this survey study, we analyzed results from the 2020 Commonwealth Fund International Health Policy (IHP) Survey-a nationally representative, self-reported, and cross-sectional survey of adults from Australia, Canada, France, Germany, the Netherlands, New Zealand, Norway, Sweden, Switzerland, the UK, and the US. Eligible adults older than age 18 years were included by random sampling. Survey data were compared for the association of area type (rural or urban) with 10 health indicators across 3 domains: health status and socioeconomic risk factors, affordability of care, and access to care. Logistic regression was used to determine the associations between countries with area type for each factor, controlling for individuals' age and sex. Main Outcomes and Measures: The main outcomes were geographic health disparities as measured by differences in respondents living in urban and rural settings in 10 health indicators across 3 domains. Results: There were 22 402 survey respondents (12 804 female [57.2%]), with a 14% to 49% response rate depending on the country. Across the 11 countries and 10 health indicators and 3 domains (health status and socioeconomic risk factors, affordability of care, access to care), there were 21 occurrences of geographic health disparities; 13 of those in which rural residence was a protective factor and 8 of those where rural residence was a risk factor. The mean (SD) number of geographic health disparities in the countries was 1.9 (1.7). The US had statistically significant geographic health disparities in 5 of 10 indicators, the most of any country, while Canada, Norway, and the Netherlands had no statistically significant geographic health disparities. The indicators with the most occurrences of geographic health disparities were in the access to care domain. Conclusions and Relevance: In this survey study of 11 high-income nations, health disparities across 10 indicators were identified. Differences in number of disparities reported by country suggest that health policy and decision makers in the US should look to Canada, Norway, and the Netherlands to improve geographic-based health equity.

Narrative minireview of the spatial epidemiology of substance use disorder in the United States: Who is at risk and where?

Drug overdose is the leading cause of death by injury in the United States. The incidence of substance use disorder (SUD) in the United States has increased steadily over the past two decades, becoming a major public health problem for the country. The drivers of the SUD epidemic in the United States have changed over time, characterized by an initial heroin outbreak between 1970 and 1999, followed by a painkiller outbreak, and finally by an ongoing synthetic opioid outbreak. The nature and sources of these abused substances reveal striking differences in the socioeconomic and behavioral factors that shape the drug epidemic. Moreover, the geospatial distribution of the SUD epidemic is not homogeneous. The United States has specific locations where vulnerable communities at high risk of SUD are concentrated, reaffirming the multifactorial socioeconomic nature of this epidemic. A better understanding of the SUD epidemic under a spatial epidemiology framework is necessary to determine the factors that have shaped its spread and how these patterns can be used to predict new outbreaks and create effective mitigation policies. This narrative minireview summarizes the current records of the spatial distribution of the SUD epidemic in the United States across different periods, revealing some spatiotemporal patterns that have preceded the occurrence of outbreaks. By analyzing the epidemic of SUD-related deaths, we also describe the epidemic behavior in areas with high incidence of cases. Finally, we describe public health interventions that can be effective for demographic groups, and we discuss future challenges in the study and control of the SUD epidemic in the country.

Lenz Lenses in a Cryoprobe: Boosting NMR Sensitivity Toward Environmental Monitoring of Mass-Limited Samples.

Nuclear magnetic resonance (NMR) spectroscopy is commonly employed in a wide range of metabolomic research. Unfortunately, due to its relatively low sensitivity, smaller samples become challenging to study by NMR. Cryoprobes can be used to increase sensitivity by cooling the coil and preamplifier, offering sensitivity improvements of ∼3 to 4x. Alternatively, microcoils can be used to increase mass sensitivity by improving sample filling and proximity, along with decreased electrical resistance. Unfortunately, combining the two approaches is not just technically challenging, but as the coil decreases, so does its thermal fingerprint, reducing the advantage of cryogenic cooling. Here, an alternative solution is proposed in the form of a Lenz lens inside a cryoprobe. Rather than replacing the detection coil, Lenz lenses allow the B1 field from a larger coil to be refocused onto a much smaller sample area. In turn, the stronger B1 field at the sample provides strong coupling to the cryocoil, improving the signal. By combining a 530 I.D. Lenz lens with a cryoprobe, sensitivity was further improved by 2.8x and 3.5x for 1H and 13C, respectively, over the cryoprobe alone for small samples. Additionally, the broadband nature of the Lenz lenses allowed multiple nuclei to be studied and heteronuclear two-dimensional (2D) NMR approaches to be employed. The sensitivity improvements and 2D capabilities are demonstrated on 430 nL of hemolymph and eight eggs (∼350 µm O.D.) from the model organismDaphnia magna. In summary, combining Lenz lenses with cryoprobes offers a relatively simple approach to boost sensitivity for tiny samples while retaining cryoprobe advantages.

Impact of healthcare capacity disparities on the COVID-19 vaccination coverage in the United States: A cross-sectional study.

Background: The impact of the COVID-19 vaccination campaign in the US has been hampered by a substantial geographical heterogeneity of the vaccination coverage. Several studies have proposed vaccination hesitancy as a key driver of the vaccination uptake disparities. However, the impact of other important structural determinants such as local disparities in healthcare capacity is virtually unknown. Methods: In this cross-sectional study, we conducted causal inference and geospatial analyses to assess the impact of healthcare capacity on the vaccination coverage disparity in the US. We evaluated the causal relationship between the healthcare system capacity of 2417 US counties and their COVID-19 vaccination rate. We also conducted geospatial analyses using spatial scan statistics to identify areas with low vaccination rates. Findings: We found a causal effect of the constraints in the healthcare capacity of a county and its low-vaccination uptake. Counties with higher constraints in their healthcare capacity were more probable to have COVID-19 vaccination rates ≤50, with 35% higher constraints in low-vaccinated areas (vaccination rates ≤ 50) compared to high-vaccinated areas (vaccination rates > 50). We also found that COVID-19 vaccination in the US exhibits a distinct spatial structure with defined "vaccination coldspots". Interpretation: We found that the healthcare capacity of a county is an important determinant of low vaccine uptake. Our study highlights that even in high-income nations, internal disparities in healthcare capacity play an important role in the health outcomes of the nation. Therefore, strengthening the funding and infrastructure of the healthcare system, particularly in rural underserved areas, should be intensified to help vulnerable communities. Funding: None.

Highly Fluorinated Peptide Probes with Enhanced In Vivo Stability for 19 F-MRI.

A labeling strategy for in vivo 19 F-MRI (magnetic resonance imaging) based on highly fluorinated, short hydrophilic peptide probes, is developed. As dual-purpose probes, they are functionalized further by a fluorophore and an alkyne moiety for bioconjugation. High fluorination is achieved by three perfluoro-tert-butyl groups, introduced into asparagine analogues by chemically stable amide bond linkages. d-amino acids and ß-alanine in the sequences endow the peptide probes with low cytotoxicity and high serum stability. This design also yielded unstructured peptides, rendering all 27 19 F substitutions chemically equivalent, giving rise to a single 19 F-NMR resonance with <10 Hz linewidth. The resulting performance in 19 F-MRI is demonstrated for six different peptide probes. Using fluorescence microscopy, these probes are found to exhibit high stability and long circulation times in living zebrafish embryos. Furthermore, the probes can be conjugated to bovine serum albumin with only amoderate increase in 19 F-NMR linewidth to ≈30 Hz. Overall, these peptide probes are hence suitable for in vivo 19 F-MRI applications.

Association Between Vaccination Coverage Disparity and the Dynamics of the COVID-19 Delta and Omicron Waves in the US.

Objective: The US recently suffered the fourth and most severe wave of the COVID-19 pandemic. This wave was driven by the SARS-CoV-2 Omicron, a highly transmissible variant that infected even vaccinated people. Vaccination coverage disparities have played an important role in shaping the epidemic dynamics. Analyzing the epidemiological impact of this uneven vaccination coverage is essential to understand local differences in the spread and outcomes of the Omicron wave. Therefore, the objective of this study was to quantify the impact of vaccination coverage disparity in the US in the dynamics of the COVID-19 pandemic during the third and fourth waves of the pandemic driven by the Delta and Omicron variants. Methods: This cross-sectional study used COVID-19 cases, deaths, and vaccination coverage from 2,417 counties. The main outcomes of the study were new COVID-19 cases (incidence rate per 100,000 people) and new COVID-19 related deaths (mortality rate per 100,000 people) at county level and the main exposure variable was COVID-19 vaccination rate at county level. Geospatial and data visualization analyses were used to estimate the association between vaccination rate and COVID-19 incidence and mortality rates for the Delta and Omicron waves. Results: During the Omicron wave, areas with high vaccination rates (>60%) experienced 1.4 (95% confidence interval [CI] 1.3-1.7) times higher COVID-19 incidence rate compared to areas with low vaccination rates (<40%). However, mortality rate was 1.6 (95% CI 1.5-1.7) higher in these low-vaccinated areas compared to areas with vaccination rates higher than 60%. As a result, areas with low vaccination rate had a 2.2 (95% CI 2.1-2.2) times higher case-fatality ratio. Geospatial clustering analysis showed a more defined spatial structure during the Delta wave with clusters with low vaccination rates and high incidence and mortality located in southern states. Conclusions: Despite the emergence of new virus variants with differential transmission potential, the protective effect of vaccines keeps generating marked differences in the distribution of critical health outcomes, with low vaccinated areas having the largest COVID-19 related mortality during the Delta and Omicron waves in the US. Vulnerable communities residing in low vaccinated areas, which are mostly rural, are suffering the highest burden of the COVID-19 pandemic during the vaccination era.

Implementation of a Vaccination Program Based on Epidemic Geospatial Attributes: COVID-19 Pandemic in Ohio as a Case Study and Proof of Concept.

Geospatial vaccine uptake is a critical factor in designing strategies that maximize the population-level impact of a vaccination program. This study uses an innovative spatiotemporal model to assess the impact of vaccination distribution strategies based on disease geospatial attributes and population-level risk assessment. For proof of concept, we adapted a spatially explicit COVID-19 model to investigate a hypothetical geospatial targeting of COVID-19 vaccine rollout in Ohio, United States, at the early phase of COVID-19 pandemic. The population-level deterministic compartmental model, incorporating spatial-geographic components at the county level, was formulated using a set of differential equations stratifying the population according to vaccination status and disease epidemiological characteristics. Three different hypothetical scenarios focusing on geographical subpopulation targeting (areas with high versus low infection intensity) were investigated. Our results suggest that a vaccine program that distributes vaccines equally across the entire state effectively averts infections and hospitalizations (2954 and 165 cases, respectively). However, in a context with equitable vaccine allocation, the number of COVID-19 cases in high infection intensity areas will remain high; the cumulative number of cases remained >30,000 cases. A vaccine program that initially targets high infection intensity areas has the most significant impact in reducing new COVID-19 cases and infection-related hospitalizations (3756 and 213 infections, respectively). Our approach demonstrates the importance of factoring geospatial attributes to the design and implementation of vaccination programs in a context with limited resources during the early stage of the vaccine rollout.

Integrated impedance sensing of liquid sample plug flow enables automated high throughput NMR spectroscopy.

A novel approach for automated high throughput NMR spectroscopy with improved mass-sensitivity is accomplished by integrating microfluidic technologies and micro-NMR resonators. A flow system is utilized to transport a sample of interest from outside the NMR magnet through the NMR detector, circumventing the relatively vast dead volume in the supplying tube by loading a series of individual sample plugs separated by an immiscible fluid. This dual-phase flow demands a real-time robust sensing system to track the sample position and velocities and synchronize the NMR acquisition. In this contribution, we describe an NMR probe head that possesses a microfluidic system featuring: (i) a micro saddle coil for NMR spectroscopy and (ii) a pair of interdigitated capacitive sensors flanking the NMR detector for continuous position and velocity monitoring of the plugs with respect to the NMR detector. The system was successfully tested for automating flow-based measurement in a 500 MHz NMR system, enabling high resolution spectroscopy and NMR sensitivity of 2.18 nmol s1/2 with the flow sensors in operation. The flow sensors featured sensitivity to an absolute difference of 0.2 in relative permittivity, enabling distinction between most common solvents. It was demonstrated that a fully automated NMR measurement of nine individual 120 µL samples could be done within 3.6 min or effectively 15.3 s per sample.

A survey of Alberta pharmacists' attitudes, comfort and perceived barriers to a community-based naloxone program.

BACKGROUND: Community pharmacists play an important role in the wellness of patients, families and friends affected by prescription and illicit opioid drugs. They are key partners of the Community Based Naloxone (CBN) Program in Alberta and similar programs across other Canadian jurisdictions. This publicly funded program is an evidence-based response to the opioid overdose crisis, facilitating access to and distribution of naloxone kits through pharmacies. The study aimed to describe Alberta community pharmacists' practices, training, comfort levels and views in dispensing naloxone kits through the CBN program and detail potential perceived barriers to program participation. METHODS: The study was conducted as a cross-sectional online survey of Alberta pharmacists. Data collected from the survey were descriptive and evaluated using Microsoft Excel. Fisher exact tests were used to study the associations in responses among several demographic characteristics and related to dispensing practices, pharmacists' beliefs and perceived barriers. RESULTS: A total of 255 responses were included in the final analysis, with 89.8% of pharmacists replying "yes" to CBN program participation. Pharmacists on average were "comfortable" dispensing naloxone to patients for varying indications, with 85% reporting always providing education when dispensing naloxone to an individual for the first time. About 41% of pharmacists reported no barriers to the program, with the most common perceived barriers being lack of time (29%), demand (20%) and funding (19%). CONCLUSION: Most community pharmacists who responded to the survey participate in the CBN program in Alberta. They held positive beliefs about their role in screening patients for the risk of opioid overdose and are confident in their abilities to recommend and educate on naloxone kits. Proactive screening appeared lower, however, and dispensing kits were potentially variable. Addressing factors such as time, funding for services and demand may help further pharmacist uptake and success of the program. Can Pharm J (Ott) 2021;154:xx-xx.

Real-Time NMR Monitoring of Spatially Segregated Enzymatic Reactions in Multilayered Hydrogel Assemblies*.

Compartmentalized chemical reactions at the microscale are important in biotechnology, yet monitoring the molecular content at these small scales is challenging. To address this challenge, we integrate a compact, reconfigurable reaction cell featuring electrochemical functionality with high-resolution NMR spectroscopy. We demonstrate the operation of this system by monitoring the activity of enzymes immobilized in chemically distinct layers within a multi-layered chitosan hydrogel assembly. As a benchmark, we observed the parallel activities of urease (Urs), catalase (Cat), and glucose oxidase (GOx) by monitoring reagent and product concentrations in real-time. Simultaneous monitoring of an independent enzymatic process (Urs) together with a cooperative process (GOx + Cat) was achieved, with chemical conversion modulation of the GOx + Cat process demonstrated by varying the order in which the hydrogel was assembled.

"Know your epidemic, know your response": Epidemiological assessment of the substance use disorder crisis in the United States.

The United States (U.S.) is currently experiencing a substance use disorders (SUD) crisis with an unprecedented magnitude. The objective of this study was to recognize and characterize the most vulnerable populations at high risk of SUD mortality in the U.S., and to identify the locations where these vulnerable population are located. We obtained the most recent available mortality data for the U.S. population aged 15-84 (2005-2017) from the Centers for Diseases and Prevention (CDC). Our analysis focused on the unintentional substance poisoning to estimate SUD mortality. We computed health-related comorbidities and socioeconomic association with the SUD distribution. We identified the most affected populations and conducted a geographical clustering analysis to identify places with increased concentration of SUD related deaths. From 2005-2017, 463,717 SUD-related deaths occurred in the United States. White population was identified with the highest SUD death proportions. However, there was a surge of the SUD epidemic in the Black male population, with a sharp increase in the SUD-related death rate since 2014. We also found that an additional average day of mental distress might increase the relative risk of SUD-related mortality by 39%. The geographical distribution of the epidemic showed clustering in the West and Mid-west regions of the U.S. In conclusion, we found that the SUD epidemic in the U.S. is characterized by the emergence of several micro-epidemics of different intensities across demographic groups and locations within the country. The comprehensive description of the epidemic presented in this study could assist in the design and implementation of targeted policy interventions for addiction mitigation campaigns.

Identification of Vulnerable Populations and Areas at Higher Risk of COVID-19-Related Mortality during the Early Stage of the Epidemic in the United States.

We characterized vulnerable populations located in areas at higher risk of COVID-19-related mortality and low critical healthcare capacity during the early stage of the epidemic in the United States. We analyze data obtained from a Johns Hopkins University COVID-19 database to assess the county-level spatial variation of COVID-19-related mortality risk during the early stage of the epidemic in relation to health determinants and health infrastructure. Overall, we identified highly populated and polluted areas, regional air hub areas, race minorities (non-white population), and Hispanic or Latino population with an increased risk of COVID-19-related death during the first phase of the epidemic. The 10 highest COVID-19 mortality risk areas in highly populated counties had on average a lower proportion of white population (48.0%) and higher proportions of black population (18.7%) and other races (33.3%) compared to the national averages of 83.0%, 9.1%, and 7.9%, respectively. The Hispanic and Latino population proportion was higher in these 10 counties (29.3%, compared to the national average of 9.3%). Counties with major air hubs had a 31% increase in mortality risk compared to counties with no airport connectivity. Sixty-eight percent of the counties with high COVID-19-related mortality risk also had lower critical care capacity than the national average. The disparity in health and environmental risk factors might have exacerbated the COVID-19-related mortality risk in vulnerable groups during the early stage of the epidemic.

Untuned broadband spiral micro-coils achieve sensitive multi-nuclear NMR TX/RX from microfluidic samples.

The low frequency plateau in the frequency response of an untuned micro-resonator permits broadband radio-frequency reception, albeit at the expense of optimal signal-to-noise ratio for a particular nucleus. In this contribution we determine useful figures of merit for broadband micro-coils, and thereby explore the parametric design space towards acceptable simultaneous excitation and reception of a microfluidic sample over a wide frequency band ranging from 13C to 1H, i.e., 125-500 MHz in an 11.74 T magnet. The detector achieves 37% of the performance of a comparably sized, tuned and matched resonator, and a linewidth of 17 ppb using standard magnet shims. The use of broadband detectors circumvents numerous difficulties introduced by multi-resonant RF detector circuits, including sample loading effects on matching, channel isolation, and field distortion.

Dynamics of the COVID-19 epidemic in urban and rural areas in the United States.

PURPOSE: There is a growing concern about the COVID-19 epidemic intensifying in rural areas in the United States (U.S.). In this study, we described the dynamics of COVID-19 cases and deaths in rural and urban counties in the U.S. METHODS: Using data from April 1 to November 12, 2020, from Johns Hopkins University, we estimated COVID-19 incidence and mortality rates and conducted comparisons between urban and rural areas in three time periods at the national level, and in states with higher and lower COVID-19 incidence rates. RESULTS: Results at the national level showed greater COVID-19 incidence rates in urban compared to rural counties in the Northeast and Mid-Atlantic regions of the U.S. at the beginning of the epidemic. However, the intensity of the epidemic has shifted to a rapid surge in rural areas. In particular, high incidence states located in the Mid-west of the country had more than 3,400 COVID-19 cases per 100,000 people compared to 1,284 cases per 100,000 people in urban counties nationwide during the third period (August 30 to November 12). CONCLUSIONS: Overall, the current epicenter of the epidemic is located in states with higher infection rates and mortality in rural areas. Infection prevention and control efforts including healthcare capacity should be scaled up in these vulnerable rural areas.