A linear SARS-CoV-2 DNA vaccine candidate reduces virus shedding in ferrets.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), has caused more than 760 million cases and over 6.8 million deaths as of March 2023. Vaccination has been the main strategy used to contain the spread of the virus and to prevent hospitalizations and deaths. Currently, two mRNA-based vaccines and one adenovirus-vectored vaccine have been approved and are available for use in the U.S. population. The versatility, low cost, and rapid production of DNA vaccines provide important advantages over other platforms. Additionally, DNA vaccines efficiently induce both B- and T-cell responses by expressing the antigen within transfected host cells, and the antigen, after being processed into peptides, can associate with MHC class I or II of antigen-presenting cells (APCs) to stimulate different T cell responses. However, the efficiency of DNA vaccination needs to be improved for use in humans. Importantly, in vivo DNA delivery combined with electroporation (EP) has been used successfully in the field of veterinary oncology, resulting in high rates of response after electrochemotherapy. Here, we evaluate the safety, immunogenicity, and protective efficacy of a novel linear SARS-CoV-2 DNA vaccine candidate delivered by intramuscular injection followed by electroporation (Vet-ePorator™) in ferrets. The linear SARS-CoV-2 DNA vaccine candidate did not cause unexpected side effects. Additionally, the vaccine elicited neutralizing antibodies and T cell responses on day 42 post-immunization using a low dose of the linear DNA construct in a prime-boost regimen. Most importantly, vaccination significantly reduced shedding of infectious SARS-CoV-2 through oral and nasal secretions in a ferret model.

A linear DNA encoding the SARS-CoV-2 receptor binding domain elicits potent immune response and neutralizing antibodies in domestic cats.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiologic agent of the COVID-19 pandemic, has been shown to infect a wide range of animal species, especially mammals, and besides human-to-human transmission, human-to-animal transmission has also been observed in some wild animals and pets, especially in cats. It has been demonstrated that cats are permissive to COVID-19 and are susceptible to airborne infections. Given the high transmissibility potential of SARS-CoV-2 to different host species and the close contact between humans and animals, it is crucial to find mechanisms to prevent the transmission chain and reduce the risk of spillover to susceptible species. Here, we show results from a clinical trial conducted in domestic cats to assess safety and immunogenicity of a linear DNA (linDNA) vaccine encoding the receptor-binding domain (RBD) from SARS-CoV-2 (Lin-COVID-eVax). Lin-COVID-eVax proved to be safe, with no significant adverse events, and was able to elicit both RBD-specific antibodies and T cells. Also, the linDNA vaccine induced neutralizing antibody titers against ancestral SARS-CoV-2 virus and its variants. These findings demonstrate the safety and immunogenicity of a genetic vaccine against COVID-19 administered to cats and strongly support the development of vaccines for preventing viral spread in susceptible species, especially those in close contact with humans.

Methanol synthesis from CO2 and H2 using supported Pd alloy catalysts.

A number of Pd based materials have been synthesised and evaluated as catalysts for the conversion of carbon dioxide and hydrogen to methanol, a useful platform chemical and hydrogen storage molecule. Monometallic Pd catalysts show poor methanol selectivity, but this is improved through the formation of Pd alloys, with both PdZn and PdGa alloys showing greatly enhanced methanol productivity compared with monometallic Pd/Al2O3 and Pd/TiO2 catalysts. Catalyst characterisation shows that the 1 : 1 ß-PdZn alloy is present in all Zn containing post-reaction samples, including PdZn/Ga2O3, with the Pd2Ga alloy formed for the Pd/Ga2O3 sample. The heat of mixing was calculated for a variety of alloy compositions with high values determined for both PdZn and Pd2Ga alloys, at ca. -0.6 eV per atom and ca. -0.8 eV per atom, respectively. However, ZnO is more readily reduced than Ga2O3, providing a possible explanation for the preferential formation of the PdZn alloy, rather than PdGa, when in the presence of Ga2O3.

Linear DNA amplicons as a novel cancer vaccine strategy.

BACKGROUND: DNA-based vaccines represent a simple, safe and promising strategy for harnessing the immune system to fight infectious diseases as well as various forms of cancer and thus are considered an important tool in the cancer immunotherapy toolbox. Nonetheless, the manufacture of plasmid DNA vaccines has several drawbacks, including long lead times and the need to remove impurities from bacterial cultures. Here we report the development of polymerase chain reaction (PCR)-produced amplicon expression vectors as DNA vaccines and their in vivo application to elicit antigen-specific immune responses in animal cancer models. METHODS: Plasmid DNA and amplicon expression was assessed both in vitro, by Hela cells transfection, and in vivo, by evaluating luciferase expression in wild-type mice through optical imaging. Immunogenicity induced by DNA amplicons was assessed by vaccinating wild-type mice against a tumor-associated antigen, whereas the antitumoral effect of DNA amplicons was evaluated in a murine cancer model in combination with immune-checkpoint inhibitors (ICIs). RESULTS: Amplicons encoding tumor-associated-antigens, such as telomerase reverse transcriptase or neoantigens expressed by murine tumor cell lines, were able to elicit antigen-specific immune responses and proved to significantly impact tumor growth when administered in combination with ICIs. CONCLUSIONS: These results strongly support the further exploration of the use of PCR-based amplicons as an innovative immunotherapeutic approach to cancer treatment.

The Critical Role of ßPdZn Alloy in Pd/ZnO Catalysts for the Hydrogenation of Carbon Dioxide to Methanol.

The rise in atmospheric CO2 concentration and the concomitant rise in global surface temperature have prompted massive research effort in designing catalytic routes to utilize CO2 as a feedstock. Prime among these is the hydrogenation of CO2 to make methanol, which is a key commodity chemical intermediate, a hydrogen storage molecule, and a possible future fuel for transport sectors that cannot be electrified. Pd/ZnO has been identified as an effective candidate as a catalyst for this reaction, yet there has been no attempt to gain a fundamental understanding of how this catalyst works and more importantly to establish specific design criteria for CO2 hydrogenation catalysts. Here, we show that Pd/ZnO catalysts have the same metal particle composition, irrespective of the different synthesis procedures and types of ZnO used here. We demonstrate that all of these Pd/ZnO catalysts exhibit the same activity trend. In all cases, the ß-PdZn 1:1 alloy is produced and dictates the catalysis. This conclusion is further supported by the relationship between conversion and selectivity and their small variation with ZnO surface area in the range 6-80 m2g-1. Without alloying with Zn, Pd is a reverse water-gas shift catalyst and when supported on alumina and silica is much less active for CO2 conversion to methanol than on ZnO. Our approach is applicable to the discovery and design of improved catalysts for CO2 hydrogenation and will aid future catalyst discovery.

Rapid authentication of pharmaceuticals via DNA tagging and field detection.

A small PCR-generated DNA fragment was introduced into a pharmaceutical grade ink as a molecular taggant, and the DNA tagged ink was delivered onto the surface of capsules by standard high-speed offset printing. The amount of DNA in the ink on each capsule is roughly 10-12 fold lower than that allowed as safe by the United States Food and Drug Administration (FDA) and the WHO with regards to acceptable limits of residual DNA. The printed ink on the capsule surface was sampled by swabbing, followed by direct analysis of the DNA-swab complex, without subsequent DNA purification. It was shown that DNA recovered from the ink by swabbing was suitable for PCR-CE analysis-a widely used method in forensic science and was also suitable for qPCR and isothermal DNA amplification, when coupled with portable devices similar to those used for environmental sampling and food safety testing. The data set a precedent: A small DNA fragment could be introduced as an excipient into a pharmaceutical application, and thereafter tracked through the pharmaceutical supply chain via forensic DNA authentication.

Predator-prey dynamics of bald eagles and glaucous-winged gulls at Protection Island, Washington, USA.

Bald eagle (Haliaeetus leucocephalus) populations in North America rebounded in the latter part of the twentieth century, the result of tightened protection and outlawing of pesticides such as DDT. An unintended consequence of recovery may be a negative impact on seabirds. During the 1980s, few bald eagles disturbed a large glaucous-winged gull (Larus glaucescens) colony on Protection Island, Washington, USA, in the Salish Sea. Breeding gull numbers in this colony rose nearly 50% during the 1980s and early 1990s. Beginning in the 1990s, a dramatic increase in bald eagle activity ensued within the colony, after which began a significant decline in gull numbers.To examine whether trends in the gull colony could be explained by eagle activity, we fit a Lotka-Volterra-type predator-prey model to gull nest count data and Washington State eagle territory data collected in most years between 1980 and 2016. Both species were assumed to grow logistically in the absence of the other.The model fits the data with generalized R 2 = 0.82, supporting the hypothesis that gull dynamics were due largely to eagle population dynamics.Point estimates of the model parameters indicated approach to stable coexistence. Within the 95% confidence intervals for the parameters, however, 11.0% of bootstrapped parameter vectors predicted gull colony extinction.Our results suggest that the effects of bald eagle activity on the dynamics of a large gull colony were explained by a predator-prey relationship that included the possibility of coexistence but also the possibility of gull colony extinction. This study serves as a cautionary exploration of the future, not only for gulls on Protection Island, but for other seabirds in the Salish Sea. Managers should monitor numbers of nests in seabird colonies as well as eagle activity within colonies to document trends that may lead to colony extinction.

The Effects of Secondary Oxides on Copper-Based Catalysts for Green Methanol Synthesis.

Catalysts for methanol synthesis from CO2 and H2 have been produced by two main methods: co-precipitation and supercritical anti-solvent (SAS) precipitation. These two methods are compared, along with the behaviour of copper supported on Zn, Mg, Mn, and Ce oxides. Although the SAS method produces initially active material with high Cu specific surface area, they appear to be unstable during reaction losing significant amounts of surface area and hence activity. The CuZn catalysts prepared by co-precipitation, however, showed much greater thermal and reactive stability than the other materials. There appeared to be the usual near-linear dependence of activity upon Cu specific area, though the initial performance relationship was different from that post-reaction, after some loss of surface area. The formation of the malachite precursor, as reported before, is important for good activity and stability, whereas if copper oxides are formed during the synthesis and ageing process, then a detrimental effect on these properties is seen.

The effect of sodium species on methanol synthesis and water-gas shift Cu/ZnO catalysts: utilising high purity zincian georgeite.

The effect of sodium species on the physical and catalytic properties of Cu/ZnO catalysts derived from zincian georgeite has been investigated. Catalysts prepared with <100 ppm to 2.1 wt% Na+, using a supercritical CO2 antisolvent technique, were characterised and tested for the low temperature water-gas shift reaction and also CO2 hydrogenation to methanol. It was found that zincian georgeite catalyst precursor stability was dependent on the Na+ concentration, with the 2.1 wt% Na+-containing sample uncontrollably ageing to malachite and sodium zinc carbonate. Samples with lower Na+ contents (<100-2500 ppm) remained as the amorphous zincian georgeite phase, which on calcination and reduction resulted in similar CuO/Cu particle sizes and Cu surface areas. The aged 2.1 wt% Na+ containing sample, after calcination and reduction, was found to comprise of larger CuO crystallites and a lower Cu surface area. However, calcination of the high Na+ sample immediately after precipitation (before ageing) resulted in a comparable CuO/Cu particle size to the lower (<100-2500 ppm) Na+ containing samples, but with a lower Cu surface area, which indicates that Na+ species block Cu sites. Activity of the catalysts for the water-gas shift reaction and methanol yields in the methanol synthesis reaction correlated with Na+ content, suggesting that Na+ directly poisons the catalyst. In situ XRD analysis showed that the ZnO crystallite size and consequently Cu crystallite size increased dramatically in the presence of water in a syn-gas reaction mixture, showing that stabilisation of nanocrystalline ZnO is required. Sodium species have a moderate effect on ZnO and Cu crystallite growth rate, with lower Na+ content resulting in slightly reduced rates of growth under reaction conditions.

Does sharing the electronic health record in the consultation enhance patient involvement? A mixed-methods study using multichannel video recording and in-depth interviews in primary care.

BACKGROUND: Sharing the electronic health-care record (EHR) during consultations has the potential to facilitate patient involvement in their health care, but research about this practice is limited. METHODS: We used multichannel video recordings to identify examples and examine the practice of screen-sharing within 114 primary care consultations. A subset of 16 consultations was viewed by the general practitioner and/or patient in 26 reflexive interviews. Screen-sharing emerged as a significant theme and was explored further in seven additional patient interviews. Final analysis involved refining themes from interviews and observation of videos to understand how screen-sharing occurred, and its significance to patients and professionals. RESULTS: Eighteen (16%) of 114 videoed consultations involved instances of screen-sharing. Screen-sharing occurred in six of the subset of 16 consultations with interviews and was a significant theme in 19 of 26 interviews. The screen was shared in three ways: 'convincing' the patient of a diagnosis or treatment; 'translating' between medical and lay understandings of disease/medication; and by patients 'verifying' the accuracy of the EHR. However, patients and most GPs perceived the screen as the doctor's domain, not to be routinely viewed by the patient. CONCLUSIONS: Screen-sharing can facilitate patient involvement in the consultation, depending on the way in which sharing comes about, but the perception that the record belongs to the doctor is a barrier. To exploit the potential of sharing the screen to promote patient involvement, there is a need to reconceptualise and redesign the EHR.

"How long does it take?" A mixed methods evaluation of computer-related work in GP consultations.

BACKGROUND: Systematic reviews have suggested that time spent on computer-related tasks increases consultation length. However, these reviews pre-date the current ubiquitous use of computers in U.K. general practice. OBJECTIVE: As part of a U.K. national study of the influence of information technology (IT) on the interaction between patients and healthcare professionals during consultations, we explored how IT functions affected time allocation and styles of computer use during general practitioner (GP) consultations. METHODS: We drew on multichannel video recording of consultations and measured consultation phases and the duration of computer-related tasks. We related measures of actual time to GP's interpretation of computer use elicited in qualitative interviews. RESULTS: Our sample included recordings of 112 consultations from 6 GPs in three practices. The computer was used for about one-third of the greater consultation. However, its use was concentrated pre- and post- the patient consultation. The workflow of consultation was exemplified through six computer use cases. Most functionality was accepted and accommodated within the consultation, though disruptive and time-consuming tasks were generally delegated to administrative staff. Recognised styles of computer use (minimal, block and conversational) were apparent, but applied very flexibly by GPs according to the nature of the consultation. CONCLUSIONS: In contrast to earlier reports, contemporary computer use does not appear to have lengthened consultations. GPs adopted different styles of computer use in different consultations, challenging classifications that seek to stereotype GP computer use. Designing systems that support this versatility require an understanding of the fluid application of computer use within consultation structure.

The role of DNA-stained currency in gang robberies within the United Kingdom.

Cash-and-valuables-in-transit (CViT) robberies have become a substantial problem-especially in the current global economy. Over £19.4 million were stolen in 2008 and £17.1 million in 2009 in the United Kingdom alone. The transportation of cash and valuable items between financial institutions has long been a target of robberies in the U.K. After a robbery has occurred, police collect evidence in the form of ink-stained currency. These stained notes are submitted for analysis. Samples are subjected to polymerase chain reaction in order to amplify any possible botanically derived DNA markers present on the notes. After amplification, capillary electrophoresis allows for the deciphering of the "DNA profile." The DNA profile is then linked to a particular cash box, and this information is compared with records of whether or not that box had been stolen. The cases below are three such instances where botanically marked currency was used to help solve robberies.

'Too much, too late': mixed methods multi-channel video recording study of computerized decision support systems and GP prescribing.

OBJECTIVE: Computerized decision support systems (CDSS) are commonly deployed to support prescribing, although over-riding of alerts by prescribers remains a concern. We aimed to understand how general practitioners (GPs) interact with prescribing CDSS in order to inform deliberation on how better to support prescribing decisions in primary care. MATERIALS AND METHODS: Quantitative and qualitative analysis of interactions between GPs, patients, and computer systems using multi-channel video recordings of 112 primary care consultations with eight GPs in three UK practices. RESULTS: 132 prescriptions were issued in the course of 73 of the consultations, of which 81 (61%) attracted at least one alert. Of the total of 117 alerts, only three resulted in the GP checking, but not altering, the prescription. CDSS provided information and safety alerts at the point of generating a prescription. This was 'too much, too late' as the majority of the 'work' of prescribing occurred prior to using the computer. By the time an alert appeared, the GP had formulated the problem(s), potentially spent several minutes considering, explaining, negotiating, and reaching agreement with the patient about the proposed treatment, and had possibly given instructions and printed an information leaflet. DISCUSSION: CDSS alerts do not coincide with the prescribing workflow throughout the whole GP consultation. Current systems interrupt to correct decisions that have already been taken, rather than assisting formulation of the management plan. CONCLUSIONS: CDSS are likely to be more acceptable and effective if the prescribing support is provided much earlier in the process of generating a prescription.

Is lidocaine Bier's block safe?

OBJECTIVES: To assess the safety profile of lidocaine Bier's block when compared with that of prilocaine. METHOD: A retrospective audit of patients undergoing Bier's block using 0.5% lidocaine during a 27-month period (April 2008-June 2010) at the Royal United Hospital Bath emergency department. RESULTS: 416 patients with sufficient data were included in the study; 360 women and 56 men. The mean patient age was 65 years. Complications were reported in 39 cases; transient hypotension/vasovagal episodes and transient mild bradycardia were most frequent. No patients required any medical intervention. There was no occurrence of anaphylaxis, convulsion, hypotensive episodes requiring medical intervention, collapse or death. CONCLUSION: No clinically significant morbidity or mortality as a consequence of lidocaine Bier's block was demonstrated in this audit.

Coping behaviour as an adaptation to stress: post-disturbance preening in colonial seabirds.

In humans, coping behaviour is an action taken to soothe oneself during or after a stressful or threatening situation. Some human behaviours with physiological functions also serve as coping behaviours, for example, comfort sucking in infants and comfort eating in adults. In birds, the behaviour of preening, which has important physiological functions, has been postulated to soothe individuals after stressful situations. We combine two existing modelling approaches - logistic regression and Darwinian dynamics - to explore theoretically how a behaviour with crucial physiological function might evolve into a coping behaviour. We apply the method to preening in colonial seabirds to investigate whether and how preening might be co-opted as a coping behaviour in the presence of predators. We conduct an in-depth study of the environmental correlates of preening in a large gull colony in Washington, USA, and we perform an independent field test for comfort preening by computing the change in frequency of preening in gulls that were alerted to a predator, but did not flee.

Mathematical modeling of appendicular bone growth in glaucous-winged gulls.

Development of locomotor activity is crucial in tetrapods. In birds, this development leads to different functions for hindlimbs and forelimbs. The emergence of walking and flying as very different complex behavior patterns only weeks after hatching provides an interesting case study in animal development. We measured the diaphyseal lengths and midshaft diameters of three wing bones (humerus, ulna, and carpometacarpus) and three leg bones (femur, tibiotarsus, and tarsometatarsus) of 79 juvenile (ages 0-42 days) and 13 adult glaucous-winged gulls (Larus glaucescens), a semiprecocial species. From a suite of nine alternative mathematical models, we used information-theoretic criteria to determine the best model(s) for length and diameter of each bone as a function of age; that is, we determined the model(s) that obtained the best tradeoff between the minimized sum of squared residuals and the number of parameters used to fit the model. The Janoschek and Holling III models best described bone growth, with at least one of these models yielding an R(2) > or = 0.94 for every dimension except tarsometatarsus diameter (R(2) = 0.87). We used the best growth models to construct accurate allometric comparisons of the bones. Early maximal absolute growth rates characterize the humerus, femur, and tarsometatarsus, bones that assume adult-type support functions relatively early during juvenile development. Leg bone lengths exhibit more rapid but less sustained relative growth than wing bone lengths. Wing bone diameters are initially smaller than leg bone diameters, although this relationship is reversed by fledging. Wing bones and the femur approach adult length by fledging but continue to increase in diameter past fledging; the tibiotarsus and tarsometatarsus approach both adult length and diameter by fledging. In short, the pattern of bone growth in this semiprecocial species reflects the changing behavioral needs of the developing organism.