Clopidogrel resistance is common in patients undergoing vascular and coronary interventions

Objectives “Clopidogrel resistance,” also defined as heightened platelet reactivity (HPR) while on clopidogrel therapy, may lead to a sub-optimal antiplatelet effect and a potential thrombotic event. There is limited literature addressing the prevalence of HPR in a large cohort of patients receiving either coronary or endovascular interventions. Methods In a large integrated healthcare system, patients with a P2Y12 reaction units (PRU) test were identified. HPR was defined as a PRU ≥ 200 during clopidogrel therapy. Vascular and coronary interventions were identified utilizing CPT codes, HPR prevalence was calculated, and Fischer’s exact test was used to determine significance. Results From an initial cohort of 2,405,957 patients (October 2014 to January 2020), we identified 3301 patients with PRU tests administered. Of these, 1789 tests had a PRU ≥ 200 (HPR overall prevalence, 54%). We then identified 1195 patients who underwent either an endovascular or coronary procedure and had a PRU measurement. This corresponded to 935 coronary and 260 endovascular interventions. In the coronary cohort, the HPR prevalence was 54% (503/935). In the vascular cohort, the HPR prevalence was 53% (137/260); there was no difference between cohorts in HPR prevalence ( p = 0.78). Conclusion “Clopidogrel resistance” or HPR was found to be present in nearly half of patients with cardiovascular disease undergoing intervention. Our data suggest HPR is more common in the cardiovascular patient population than previously appreciated. Evaluating patients for HPR is both inexpensive ($25) and rapid (< 10 min). Future randomized studies are warranted to determine whether HPR has a clinically detectable effect on revascularization outcomes.

Experimental and Molecular Docking Studies of Cyclic Diphenyl Phosphonates as DNA Gyrase Inhibitors for Fluoroquinolone-Resistant Pathogens

DNA gyrase and topoisomerase IV are proven to be validated targets in the design of novel antibacterial drugs. In this study, we report the antibacterial evaluation and molecular docking studies of previously synthesized two series of cyclic diphenylphosphonates (1a–e and 2a–e) as DNA gyrase inhibitors. The synthesized compounds were screened for their activity (antibacterial and DNA gyrase inhibition) against ciprofloxacin-resistant E.coli and Klebsiella pneumoniae clinical isolates having mutations (deletion and substitution) in QRDR region of DNA gyrase. The target compound (2a) that exhibited the most potent activity against ciprofloxacin Gram-negative clinical isolates was selected to screen its inhibitory activity against DNA gyrase displayed IC50 of 12.03 µM. In addition, a docking study was performed with inhibitor (2a), to illustrate its binding mode in the active site of DNA gyrase and the results were compatible with the observed inhibitory potency. Furthermore, the docking study revealed that the binding of inhibitor (2a) to DNA gyrase is mediated and modulated by divalent Mg2+ at good binding energy (–9.08 Kcal/mol). Moreover, structure-activity relationships (SARs) demonstrated that the combination of hydrazinyl moiety in conjunction with the cyclic diphenylphosphonate based scaffold resulted in an optimized molecule that inhibited the bacterial DNA gyrase by its detectable effect in vitro on gyrase-catalyzed DNA supercoiling activity.

Detection of Clenbuterol-Induced Changes in Heart Rate Using At-Home Recorded Smartwatch Data: Randomized Controlled Trial

Background Although electrocardiography is the gold standard for heart rate (HR) recording in clinical trials, the increasing availability of smartwatch-based HR monitors opens up possibilities for drug development studies. Smartwatches allow for inexpensive, unobtrusive, and continuous HR estimation for potential detection of treatment effects outside the clinic, during daily life. Objective The aim of this study is to evaluate the repeatability and sensitivity of smartwatch-based HR estimates collected during a randomized clinical trial. Methods The data were collected as part of a multiple-dose, investigator-blinded, randomized, placebo-controlled, parallel-group study of 12 patients with Parkinson disease. After a 6-day baseline period, 4 and 8 patients were treated for 7 days with an ascending dose of placebo and clenbuterol, respectively. Throughout the study, the smartwatch provided HR and sleep state estimates. The HR estimates were quantified as the 2.5th, 50th, and 97.5th percentiles within awake and asleep segments. Linear mixed models were used to calculate the following: (1) the intraclass correlation coefficient (ICC) of estimated sleep durations, (2) the ICC and minimum detectable effect (MDE) of the HR estimates, and (3) the effect sizes of the HR estimates. Results Sleep duration was moderately repeatable (ICC=0.64) and was not significantly affected by study day (P=.83), clenbuterol (P=.43), and study day by clenbuterol (P=.73). Clenbuterol-induced changes were detected in the asleep HR as of the first night (+3.79 beats per minute [bpm], P=.04) and in the awake HR as of the third day (+8.79 bpm, P=.001). The median HR while asleep had the highest repeatability (ICC=0.70). The MDE (N=12) was found to be smaller when patients were asleep (6.8 bpm to 11.7 bpm) than while awake (10.7 bpm to 22.1 bpm). Overall, the effect sizes for clenbuterol-induced changes were higher while asleep (0.49 to 2.75) than while awake (0.08 to 1.94). Conclusions We demonstrated the feasibility of using smartwatch-based HR estimates to detect clenbuterol-induced changes during clinical trials. The asleep HR estimates were most repeatable and sensitive to treatment effects. We conclude that smartwatch-based HR estimates obtained during daily living in a clinical trial can be used to detect and track treatment effects. Trial Registration Netherlands Trials Register NL8002; https://www.trialregister.nl/trial/8002

CRISPR-Cas9 mutagenesis and single gene reintegration suggests functional diversity within the Candida albicans TLO gene family

Candida albicans has between 10-15 Telomere-associated ORF family(TLO)genes, whereas its closest relative, Candida dubliniensis, has two. The Tlo proteins are components of the Mediator complex which plays an important role in transcriptional regulation. CRISPR-Cas9 mutagenesis was used to generate a TLOnull mutant of C. albicans. Phenotypic analysis of the mutant showed significantly reduced fitness, with major defects in growth rate, morphogenesis, stress resistance and virulence in a Galleria mellonellamodel. Clade representative TLOα1, TLOβ2 and TLOγ11constructs were reintroduced into the null mutant background to determine if members of the TLO gene family exhibit functional differences. The genes were reintroduced under the control of the TET1 and ENO1promoters. TLOα1and TLOβ2expression restored stress tolerance and growth rate, in some cases to the level of the WT. TLOβ2expression also showed a dramatic effect on morphology resulting in constitutive true hyphal growth. Moderate expression of TLOγ11 had no detectable effect on many of the phenotypes tested, however overexpression increased biofilm formation in Spider medium, and also conferred increased resistance to cell wall stressors. These data suggest that individual TLO genes have distinct functions and that the diversity within the TLO family may contribute to the relative success of C. albicans as a coloniser and pathogen of humans.

Test-retest reproducibility of in vivo magnetization transfer ratio and saturation index in mice at 9.4 Tesla

Background: Magnetization transfer saturation (MTsat) imaging was developed to reduce T1 dependence and improve specificity to myelin compared to the widely used MT ratio (MTR), while maintaining a feasible scan time. Knowledge of MTsat reproducibility is necessary to apply MTsat in preclinical neuroimaging. Purpose: To assess the test-retest reproducibility of MTR and MTsat in the mouse brain at 9.4 T and calculate sample sizes required to detect various effect sizes. Study Type: Prospective. Animal Model: C57Bl/6 Mouse Model (6 females and 6 males, aged 12 to 14 weeks). Field Strength/Sequence: Magnetization Transfer Imaging at 9.4 T. Assessment: All mice were scanned at two timepoints (5 days apart). MTR and MTsat maps were analyzed using mean region of interest (ROI), and whole brain voxel-wise analysis. Statistical Tests: Bland Altman plots assessed biases between test and retest measurements. Test retest reproducibility was evaluated via between and within-subject coefficients of variation (CV). Sample sizes required were calculated (at a 95 % significance level and power of 80 %), given various minimum detectable effect sizes, using both between and within-subject approaches. Results: Bland Altman plots showed negligible biases between test and retest sessions. ROI based and voxel-wise CVs revealed high reproducibility for both MTR (ROI: CVs < 8 %) and MTsat (ROI: CVs < 10 %). With a sample size of 6, changes on the order of 15% can be detected in MTR and MTsat, both between and within subjects, while smaller changes (6 to 8 %) require sample sizes of 10 to 15 for MTR, and 15 to 20 for MTsat. Data Conclusion: MTsat exhibits comparable reproducibility to MTR, while providing sensitivity to myelin with less T1 dependence than MTR. Our findings suggest both MTR and MTsat can detect moderate changes, common in pathologies, with feasible preclinical sample sizes. Keywords: magnetization transfer ratio, magnetization transfer saturation, reproducibility, preclinical rodent imaging

P-O15 “Knife to Skin” time: The invariable variable

Background The Covid-19 pandemic has affected all aspects of healthcare globally. Theatre utilisation assumes a substantial proportion of hospital resources, creating a streamlined pathway increases efficiency and productivity. With concerns regarding aerosol generating procedures, viral transmission to health care workers in theatre and patient pathways through the hospitals the covid-19 pandemic has added another dimension to the theatre pathway. The aim of this study was to quantify the impact of Covid-19 on the “knife to skin” (KTS) time and compare it to previous historical data (HD). Methods Retrospective analysis of real time theatre data was analysed for the first 12 months of the pandemic from 11th March 2020 to 11th March 2021. To try and minimise variability between different specialities and operations we picked one operation to study: Laparoscopic cholecystectomy (LC). Historical data was also gathered from the same time frame over the last 5 years (2015-2020) for comparison. Data collected included emergency or elective, time sent for patient, anaesthetic start time, knife to skin time and duration of operation. Comparison of means were analysed by One-way ANOVA tests and Student’s T-Test. Results 399 laparoscopic cholecystectomies were performed during the first year of the pandemic. KTS time was calculated as operation start time minus time sent for patient. Average time during the pandemic for emergency LC KTS was 56 minutes and 35 minutes for elective LC. Comparison of these times to HD revealed no statistical difference (Emergency LC 56 mins vs 58 mins p &gt; 0.05, Elective LC 35 mins vs 35 mins p &gt; 0.05). The anaesthetic time for emergency LC during the pandemic vs HD was 10 mins vs 14 mins (p &lt; 0.05), no statistical difference was found in the elective group, 16mins vs 14mins (p &gt; 0.05) Conclusions The Covid-19 pandemic has had no detectable effect on Knife to skin time as compared to our previous historical data. It seems the extra Covid 19 precautions involving PPE, pathways etc. have not affected theatre efficiency or utilisation. In fact, there was very little variance in KTS time over the six years studied (2015-2021) with very consistent levels for both elective and emergency procedures. The shorter anaesthetic time for emergency LC during the pandemic needs to be further investigated but one hypothesis is the unconscious or conscious decision to decrease the amount of preoxygenation to minimise aerosolisation.

Movement ecology of vulnerable lowland tapirs across a gradient of human disturbance

Animal movement is a key ecological process that is tightly coupled to local environmental conditions. While agriculture, urbanisation, and transportation infrastructure are critical to human socio-economic improvement, these have spurred substantial changes in animal movement across the globe with potential impacts on fitness and survival. Notably, however, human disturbance can have differential effects across species, and responses to human activities are thus largely taxa and context specific. As human disturbance is only expected to worsen over the next decade it is critical to better understand how species respond to human disturbance in order to develop effective, case-specific conservation strategies. Here, we use an extensive telemetry dataset collected over 22 years to fill a critical knowledge gap in the movement ecology of lowland tapirs (Tapirus terrestris) across a gradient of human disturbance within three biomes in southern Brazil: the Pantanal, Cerrado, and Atlantic Forest. From these data we found that the mean home range size across all monitored tapirs was 8.31 km2 (95% CI: 6.53 - 10.42), with no evidence that home range sizes differed between sexes nor age groups. Interestingly, although the Atlantic Forest, Cerrado, and Pantanal vary substantially in habitat composition, levels of human disturbance, and tapir population densities, we found that lowland tapir movement behaviour and space use were consistent across all three biomes. Human disturbance also had no detectable effect on lowland tapir movement. Lowland tapirs living in the most altered habitats we monitored exhibited movement behaviour that was comparable to that of tapirs living in a near pristine environment. Contrary to our expectations, we observed very little individual variability in lowland tapir space use and movement, and human impacts on the landscape also had no measurable effect on their movement. Lowland tapir movement behaviour thus appears to exhibit very little phenotypic plasticity. Crucially, the lack of any detectable response to anthropogenic disturbance suggests that human modified habitats risk being ecological traps for tapirs and this information should be factored into conservation actions and species management aimed towards protecting lowland tapir populations.

Diet and Nutrition of Adult Spalangia cameroni (Hymenoptera: Pteromalidae), a Parasitoid of Filth Flies

Most parasitoid wasps parasitize herbivorous insects, so nectar from flowers is readily available. However, parasitoid wasps are also an important component of the rich invertebrate communities at livestock facilities in large accumulations of manure, where flowers are largely absent. Little is known about adult parasitoid diet and nutrition in these communities. The present study examined this in Spalangia cameroni Perkins, a pupal parasitoid of filth flies. Like many parasitoid wasps, S. cameroni feed on host fluids, and in the laboratory readily feed on honey or a sucrose solution, which increases their longevity. Here adult longevity in the presence of six potential food sources, bovine manure, sorghum silage, bovine milk, buckwheat inflorescence (Polygonaceae), sweet alyssum inflorescence (Brassicaceae), or dandelion inflorescence (Asteraceae), was compared to that with water or honey. Only parasitoids given buckwheat lived as long as parasitoids given honey, and parasitoids given honey or buckwheat lived longer than parasitoids given water. Parasitoids readily ate buckwheat nectar, avoiding pollen grains. Diet affected the amount of free sugars, glycogen, and lipids in complex ways. Compared to parasitoids that were given just water, parasitoids with access to honey or sucrose had higher sugar and glycogen levels, but not detectably higher lipid levels. Access to buckwheat had no detectable effect on a parasitoid’s free sugar, glycogen, or lipid levels; however, then after 4 d with just water, sugar levels were lower and glycogen levels were higher compared to parasitoids that had been given access to only water the entire time.

Autobiographical Script-Driven Imagery Has No Detectable Effect on Emotion Regulation in Healthy Individuals

<b><i>Introduction:</i></b> Emotion regulation (ER), the ability to actively modulate one’s own emotion reactions, likely depends on the individual’s current emotional state. Here, we investigated whether negative emotions induced by an interpersonal autobiographic script affect the neuronal processes underlying ER. <b><i>Methods:</i></b> Twenty healthy participants were recruited and underwent functional magnetic resonance imaging (fMRI) during performance of distancing, a specific ER strategy, while viewing emotionally arousing pictures. Participants were instructed to either naturally experience (“permit” condition) or to actively downregulate (“regulate” condition) their emotional responses to the presented stimuli. Before each of the 4 runs in total, a neutral or negative autobiographical audio script was presented. The negative script comprised an emotionally negative event from childhood or adolescence that represented either emotional abuse or emotional neglect. The second event comprised an everyday neutral situation. We aimed at identifying the neural correlates of ER and their modulation by script-driven imagery. <b><i>Results:</i></b> fMRI analyses testing for greater responses in the “regulate” than the “permit” condition replicated previously reported neural correlates of ER in the right dorsolateral prefrontal cortex and the right inferior parietal lobule. A significant ER effect was also observed in the left orbitofrontal cortex. In the amygdala, we found greater responses in the “permit” compared to the “regulate” condition. We did not observe a significant modulation of the ER effects in any of these regions by the negative emotional state induced by autobiographical scripts. Bayesian statistics confirmed the absence of such modulations by providing marginal evidence for null effects. <b><i>Discussion:</i></b> While we replicated previously reported neural correlates of ER, we found no evidence for an effect of mood induction with individualized autobiographical scripts on the neural processes underlying ER in healthy participants.

Propolis supplementation affects performance, intestinal morphology, and bacterial population of broiler chickens

A meta-analysis was conducted to examine the effect of supplementing the diet of broiler chickens with propolis on growth, bacterial population of the intestine, antiviral serum concentration, intestinal morphology, and digestive enzyme activities in broiler chickens. Forty peer-reviewed articles that had been published between 2003 and 2019 were identified using the PRISMA protocol and included in the study. Data were analysed with mixed model methodology, in which the studies were considered random effects, whereas the level of supplemental propolis was considered a fixed effect. Responses to propolis supplementation in bodyweight (BW) and average daily gain (ADG) were quadratic, but average daily feed intake (ADFI) was not affected. Propolis supplementation improved feed conversion ratio (FCR) significantly as a linear function of the level of supplement. The optimum level of supplementation was between 256 and 262 mg/kg feed and produced maximum ADG and final BW. There was a tendency for mortality to decrease because of propolis supplementation. Propolis had no detectable effect on serum antiviral concentration, intestinal bacterial population or intestinal morphology. Among digestive enzymes, only sucrase increased linearly as propolis was increased. Thus, supplementation with propolis increased the growth performance of broiler chickens positively and the effect was dose dependent. This may have been partly because of an improvement in sucrase activity and other factors related to the nutritional content of propolis. Future study to evaluate specific bioactive compounds of propolis is therefore warranted.