Pharmacodynamic comparison of optimal platelet reactivity by multiple platelet function tests in Korean acute coronary syndrome patients with half-dose ticagrelor or prasugrel treatment

Background

East Asians treated with potent P2Y12 inhibitors, prasugrel or ticagrelor exhibit more potent platelet inhibition than clopidogrel. Whether half-dose de-escalation strategy would improve optimal platelet reactivity at maintenance in East Asian patients with acute coronary syndrome (ACS) remains uncertain.

Method

In de-escalation strategy single center study, eligible Korean ACS patients (n=96) were assigned to receive standard-dose ticagrelor (n=33), prasugrel (n=28), followed by half-dose reduction at 1 month for maintenance, and clopidogrel (n=35) as control. Platelet reactivity was measured by VerifyNow, light transmittance aggregometry (LTA) and multiple electrode aggregometry (MEA). The investigators aim to compare optimal platelet reactivity status (OPR, defined as 85–208 P2Y12 reaction unit [PRU] for VerifyNow (VN), 16%–47% for LTA and 19–46 U for MEA) among 3 different platelet function tests at 3 months post PCI.

Results

At 3 months, ticagrelor achieved significantly lower PRU (17 [6–51] vs. 95 [61–151] vs. 172 [111–204]) than prasugrel and clopidogrel, resulting OPR rate 10% vs. 57.7% vs. 60.0%, respectively. Similar results were observed at LTA method (2% [0–12] in ticagrelor vs. 18% [13–22] in prasugrel vs. 18% [11–30] in clopidogrel), with OPR rate 11.8% vs. 69.2% vs. 50.0%, respectively. However, platelet reactivity was similar by MEA method (16 [13–20] in ticagrelor vs. 17 [13–22] in prasugrel vs. 19 [14–28] in clopidogrel), with OPR rate 33.3% vs. 40.0% vs. 42.0%, respectively (all p>0.005). Among the three tests, resulting higher correlation between VN and LTA (r=0.745), MEA and LTA vs. MEA and VN showed lower correlations (r=0.412 and r=0.303). (Fig.)

Conclusion

In Korean ACS patients with half-dose de-escalation strategy after 1 month, OPR rate in ticagrelor is still rare during 3-month treatment by VN and LTA methods, however, prasugrel appears comparable to clopidogrel. VN/LTA might overestimate platelet function than MEA or MEA underestimate OPR rate than VN/LTA.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): National Research Foundation of Korea

Canadian perspective on managing multiple myeloma during the COVID-19 pandemic: lessons learned and future considerations

The coronavirus disease 2019 (covid-19) pandemic caused by the novel severe acute respiratory syndrome coronavirus 2 has necessitated changes to the way patients with chronic diseases are managed. Given that patients with multiple myeloma are at increased risk of covid-19 infection and related complications, national bodies and experts around the globe have made recommendations for risk mitigation strategies for those vulnerable patients. Understandably, because of the novelty of the virus, many of the proposed risk mitigation strategies have thus far been reactionary and cannot be supported by strong evidence. In this editorial, we highlight some of the risk mitigation strategies implemented at our institutions across Canada during the first wave of covid-19, and we discuss the considerations that should be made when managing patients during the second wave and beyond.

Controlling spin current polarization through non-collinear antiferromagnetism

The interconversion of charge and spin currents via spin-Hall effect is essential for spintronics. Energy-efficient and deterministic switching of magnetization can be achieved when spin polarizations of these spin currents are collinear with the magnetization. However, symmetry conditions generally restrict spin polarizations to be orthogonal to both the charge and spin flows. Spin polarizations can deviate from such direction in nonmagnetic materials only when the crystalline symmetry is reduced. Here, we show control of the spin polarization direction by using a non-collinear antiferromagnet Mn₃GaN, in which the triangular spin structure creates a low magnetic symmetry while maintaining a high crystalline symmetry. We demonstrate that epitaxial Mn₃GaN/permalloy heterostructures can generate unconventional spin-orbit torques at room temperature corresponding to out-of-plane and Dresselhaus-like spin polarizations which are forbidden in any sample with two-fold rotational symmetry. Our results demonstrate an approach based on spin-structure design for controlling spin-orbit torque, enabling high-efficient antiferromagnetic spintronics.

In the typical spin-hall effect, spin-current, charge current, and spin polarisation are all mutually perpendicular, a feature enforced by symmetry. Here, using an anti-ferromagnet with a triangular spin structure, the authors demonstrate a spin-hall effect without a perpendicular spin alignment.

Oral administration of alendronate and vitamin D3 for the treatment of chronic non-bacterial osteomyelitis of the jaw

Chronic non-bacterial osteomyelitis (CNO) is a rare and difficult-to-diagnose disease, especially when limited to the jaws. We report the case of a 5-year-old girl with spontaneous jaw pain and a large pre-auricular facial swelling overlying the angle of the mandible that was non-responsive to previous antibiotic and non-steroidal anti-inflammatory treatment. The diagnosis was confirmed as CNO following evaluation and workup by a multidisciplinary team. The patient exhibited a favourable response to oral alendronate sodium plus vitamin D3 combination treatment. We believe that alendronate sodium is an effective second-line drug for CNO.

[Association between tooth missing and non-alcoholic fatty liver disease]

Objective: To evaluate the association between the number of teeth missed and the prevalence of non-alcoholic fatty liver disease (NAFLD) in adults. Methods: A cross-sectional study was carried out in 26 983 adults from Tianjin Chronic Low-grade Systemic Inflammation and Health Cohort Study. The number of teeth missed (excluding third molars) was recorded and classified into four categories: 0, 1-, 3- and ≥6. NAFLD was diagnosed by at least two liver ultrasonography examinations. Adjusted multivariable logistic regression analysis was used to access the association between the number of missed teeth and NAFLD in adults. Results: The overall prevalence of NAFLD was 7 270 and the number of the subjects with at least one tooth missed was 9 667. The multivariable-adjusted ORs (95%CI) of NAFLD across the categories of tooth missing (0, 1-, 3- and ≥6) were as follows: 1.00, 1.04 (0.93-1.15), 1.08 (0.93-1.26) and 1.38 (1.09-1.76) (trend test P=0.030) in males; 1.00, 0.96 (0.82-1.12), 1.11 (0.91-1.35) and 1.22 (0.90-1.64) (trend test P=0.450) in females. Conclusion: The number of missed teeth was positively associated with a higher prevalence rate of NAFLD in males with over 6 teeth missed, but not in females.

Predictors and Barriers to Condom Use in the African Cohort Study

Consistent condom use is an inexpensive and efficacious HIV prevention strategy. Understanding factors associated with condom use and barriers to use can inform strategies to increase condom uptake. The ongoing African Cohort Study prospectively enrolls adults at 12 clinical sites in Uganda, Kenya, Tanzania, and Nigeria. At enrollment, participants are asked about condom use at last sex with a regular partner. Robust Poisson regression models were used to evaluate predictors of self-reported condom use. Participants who reported not using condoms were asked to provide reasons. From January 2013 to September 2019, 2482 participants reported having at least one regular sexual partner in the preceding 6 months. Of those, 1577 (63.5%) reported using a condom at last sex. Condom use was more common among older participants, males, HIV-infected participants, and those with an HIV-infected partner. Married participants, those with a partner of unknown HIV status, and those reporting alcohol use were less likely to report condom use at last sex. Condom use at last sex also varied significantly by clinical site. Partner disapproval or refusal to use a condom was a consistent driver of disparities in condom use among participants who were HIV infected, female, and aged 18-24 years. Effective HIV prevention programs should integrate condom education with the tools necessary to negotiate condom use with regular partners.

Genetic diversity and differentiation among Korean-Holstein, Hanwoo, and Uganda-Holstein breeds

The aim of this research was to assess genetic diversity of Korean-Holstein, Korean Hanwoo, and Ugandan-Holstein dairy cattle. DNA was extracted from either blood or hair of Korean-Holstein (n=74), Korean-Hanwoo (n=75) and Ugandan-Holstein (N=77) using AccuPrep® PCR purification kit. The DNA samples were amplified by multiplex polymerase chain reaction, using GeneTrackTM Hanwoo genotyping kit and assayed using ABI genetic analyser 3130XL. Number of alleles, expected heterozygosity (He), observed heterozygosity (Ho), and the polymorphism information content (PIC) were estimated from 10 microsatellite loci in the three breeds. In addition, F-statistics for each of the 10 microsatellites in the three cattle breeds were estimated using fstat version 2.9.3.2 computer program. GENETIX (v.4.02) was used to perform factorial correspondence analysis (FCA) from the allele frequencies and multi-locus clustering was done using STRUCTURE analyses. A total of 124 alleles were detected. The number of alleles per locus varied from eight (TGLA126) to 22 (TGLA122), with an overall mean of 12.2. Expected heterozygosity ranged from 0.617 (SPS115) to 0.854 (TGLA53) and averaged 0.761. Observed heterozygosity ranged from 0.6 (SPS115) to 0.859 (TGLA53); and averaged 0.761. The mean PIC was 0.723; and means of the F-statistics FIT, FST and FIS were 0.077, 0.076 and 0.001 respectively. Although FCA revealed clear differentiation of Uganda-Holstein, Korean-Holstein, and Hanwoo, clustering assignments showed genetic admixture between Ugandan dairy cattle (Uganda-Holstein) and Hanwoo. In conclusion, the allelic variation present at the 10 loci was sufficient to categorize these cattle into distinct breed groups. Keywords: dairy cattle, genetic differentiation, F-statistics, heterozygosity, microsatellite

Ectopic parathyroid adenoma in the submandibular region: a case report

Ectopic parathyroid adenomas that affect the submandibular region have not been widely reported. We describe a 34-year-old man who presented with a painless swelling of the submandibular region. The identification of hypercalcaemia encouraged us to engage a multidisciplinary team to evaluate further serum changes. Parathyroid hormone analysis, ^99mTc-methoxy-isobutyl-isonitrile (^99mTc-MIBI) scintigraphy, and single-photon emission computed tomography (SPECT-CT) were done to rule out hyperparathyroidism. Raised parathyroid hormone together with ^99mTc-MIBI and SPECT-CT examination were consistent with a tumour caused by the hyperparathyroidism. Removal of the lesion resulted in rapid improvement in serum calcium and parathyroid hormone, and the normalisation of the serum creatinine, concentrations. Histopathological analysis confirmed a parathyroid adenoma. We conclude that ectopic parathyroid adenomas should be considered as part of a differential diagnosis for tumours of the submandibular region.

Excessive daytime sleepiness with snoring or witnessed apnea is associated with handgrip strength: a population-based study

BACKGROUND

Sarcopenia is emerging as an important public health problem, and evidences have determined that poor sleep is associated with muscle strength, but the potential effects of excessive daytime sleepiness (EDS), snoring and witnessed apnea on handgrip strength have not been evaluated.

AIM

We aimed to examine the association between EDS, snoring, witnessed apnea and muscle strength in an adult population.

DESIGN

Cross-sectional study.

METHODS

This cross-sectional study comprised 19 434 adults. Handgrip strength was measured using a handheld digital dynamometer. EDS was assessed by Epworth Sleepiness Scale, snoring and witnessed apnea during sleep were reported through simple yes/no questions. Analysis of covariance was carried out to determine the association between EDS with snoring or witnessed apnea and muscle strength.

RESULTS

The means (95% confidence interval) for average handgrip strength/body weight (kg/kg) across symptoms categories were 0.396 (0.333-0.472), 0.393 (0.330-0.467), 0.396 (0.333-0.471) and 0.386 (0.325-0.460) (P < 0.0001), respectively. Similar results were observed with maximal handgrip strength/body weight (kg/kg).

CONCLUSIONS

Self-reported EDS accompanied with snoring or apnea is associated with lowest handgrip strength, independently of confounding factors. Whether improvement of EDS, snoring and apnea, can ameliorate age-associated decline in muscle strength warrants further studies.

Updates from the 2019 American Society of Clinical Oncology and European Hematology Association annual meetings: a Canadian perspective on high-risk cytogenetics in multiple myeloma

The 2019 annual meetings of the American Society of Clinical Oncology and the European Hematology Association took place, respectively, in Chicago, Illinois, 31 May-4 June, and in Amsterdam, Netherlands, 13-16 June. At the meetings, results from key studies on the treatment of patients with relapsed or refractory multiple myeloma with high-risk cytogenetics were presented. Our meeting report describes those studies and includes interviews with investigators and commentaries by Canadian hematologists about the potential impact on Canadian practice.

Liver kinase B1 suppresses the metastasis and angiogenesis of lung cancer: involvement of the Shh signaling pathway

Liver kinase B1 (LKB1) is revealed to have a close relationship with cancers. However, the underlying mechanism remains unclear. This study aimed to reveal the mechanism through which LKB1 performed its role in lung cancer. LKB1 shRNA and overexpression plasmid were employed to investigate the role of LKB1 in lung cancer in vitro and in vivo. The involvement of Shh signaling pathway was assessed by western blot. Silence of LKB1 promoted, while overexpression of LKB1 inhibited the migration, invasion and angiogenesis of lung cancer cells. Further study showed that Shh signaling pathway was suppressed by LKB1. Cyclopamine, a Shh signaling pathway inhibitor, reduced the effects of LKB1 silence, indicating that LKB1 inhibits the migration, invasion and angiogenesis through suppressing the Shh signaling pathway. In vivo study also showed that Shh signaling pathway was involved in the modulation of LKB1 on the metastasis and angiogenesis of lung cancer. Our study demonstrates that LKB1 inhibits the metastasis and angiogenesis of lung cancer through suppressing the Shh signaling pathway.

T1ρ MRI of the talar articular cartilage is increased in those with chronic ankle instability

OBJECTIVE

To determine if individuals with chronic ankle instability (CAI) demonstrate different talar cartilage T1ρ relaxation times compared to uninjured controls.

DESIGN

Fifteen CAI (21.13 ± 1.81 years, 4.00 ± 2.07 previous ankle sprains) and fifteen controls (21.07 ± 2.55 years, no previous ankle sprains) participated. CAI inclusion criteria was in accordance with the International Ankle Consortium guidelines. Greater T1ρ relaxation times were interpreted as greater degenerative changes. Participants were non-weight bearing for 30-minutes prior to scanning to unload the cartilage. Voxel by voxel T1ρ relaxation times were calculated from a five image sequence. Segmentation of the talar cartilage was performed manually using ITK-SNAP software. T1ρ relaxation time means and variability across the entire talus and in the anteromeidal, anterolateral, posteromedial, and posterolateral regions of interest (ROIs) were compared between groups using mean differences and effect sizes (ES) with their corresponding 95% confidence intervals (95%CI).

RESULTS

Individuals with CAI demonstrated higher T1ρ relaxation times (mean ± standard deviation) across the entire talus (CAI: 65.97 ± 10.45 ms, Control: 58.84 ± 7.68 ms; ES = 0.76, 95%CI = 0.02-1.50), in the anterolateral (ES = 1.00, 95%CI = 0.24-1.48), posteromedial (ES = 0.74, 95%CI = 0.01-1.49), and posterolateral region of interest (ES = 3.84, 95%CI = 2.63-5.04). The T1ρ relaxation time variability (mean ± standard deviation) also differed across the overall talus (CAI: 32.78 ± 4.06 ms, Control: 28.23 ± 4.45 ms; ES = 1.04, 95%CI = 0.28-1.80), in the anteriolateral, (ES = 1.07, 95%CI = 0.31, 1.84) and posteriolateral (ES = 1.00, 95%CI = 0.24-1.75) ROIs.

CONCLUSIONS

Individuals with CAI demonstrate greater T1ρ relaxation times and higher T1ρ variability compared to uninjured controls. This finding supports the existing literature illustrating early degenerative joint tissue changes consistent with early onset posttraumatic osteoarthritis in individuals with CAI.

[Impact of discontinuation of aspirin and clopidogrel before off-pump coronary artery bypass grafting on postoperative bleeding and transfusion requirement]

Objective: To investigate the influence of different discontinuation time of aspirin and clopidogrel before off-pump coronary artery bypass grafting (OPCABG) on postoperative bleeding and blood products transfusion requirement. Methods: Three hundred and fifty-three coronary artery disease patients who underwent OPCABG from January 2017 to January 2018 at Department of Cardiac Surgery, Zhongshan Hospital, Fudan University were retrospectively analysed. There were 268 males and 85 females, aged (66.0±9.1)years. All patients were divided into three groups: (1) guideline-recommended group: patients who discontinued clopidogrel for >5 days without discontinuing aspirin before surgery; (2) without discontinuing group: patients who discontinued clopidogrel for ≤5 days without discontinuing aspirin before surgery; (3) discontinuing group: patients who discontinued clopidogrel for >5 days with discontinuing aspirin before surgery. Postoperative bleeding recorded as chest tube drainage (CTD) volume and blood products transfusion requirement and perioperative complications were recorded. CTD volumes within 12 hours after surgery between groups were compared by Mann-Whitney U tests, CTD volumes after 12 hours postoperatively were compared by repeated measures analysis of variance and blood products transfusion and complications incidence were compared by χ(2) test or Fisher's precise test. Results: The 12 hours CTD volumes of guideline-recommended group, without discontinuing group, discontinuing group after surgery were 280(153) ml (M(Q(R))), 291(229) ml, 225(161) ml, respectively. There were no significant differences in postoperative 12 hours CTD volumes (P=0.865), red blood cells transfusion incidence (χ(2)=2.626, P=0.149) and fresh frozen plasma (FFP) transfusion incidence (χ(2)=1.258, P=0.324) between guideline-recommended group and without discontinuing group. However, the 12 hours CTD volumes were significantly higher in guideline-recommended group patients compared with disconutinuing group patients (U=5 247, P=0.002). No significant differences were observed in red blood cells (χ(2)=0.182, P=0.757) and FFP (χ(2)=0.083, P=0.839) transfusion rate between these two groups. Repeated measures analysis of variance indicated that when patients began to take antiplatelet drugs (aspirin and clopidogrel) after 12 hours postoperatively, the change of CTD volumes beyond 12 hours after surgery didn't differ either between guideline-recommended group and without discontinuing group (F=0.019, P=0.941) or between guideline-recommended group and discontinuing group (F=2.447,P=0.113). Besides, the incidence of perioperative arrhythmia was significantly higher in guideline-recommended group patients compared with without discontinuing group patients (4.8% vs. 0, χ(2)=5.073, P=0.038). Conclusions: OPCABG patients who discontinued aspirin before surgery had lower postoperative 12 hours CTD volumes but similar blood products transfusion rate and CTD volumes beyond 12 hours postoperatively compared with patients adhering to the current guideline-recommended protocol. And for patients who discontinued clopidogrel for ≤5 days, postoperative CTD volumes and blood products transfusion requirement were similar but the incidence of perioperative arrhythmia was significantly lower compared with guideline-treated patients.

Serum Stem Cell Factor Level Predicts Decline in Kidney Function in Healthy Aging Adults

BACKGROUND AND OBJECTIVES

Stem cell factor (SCF), the ligand of the c-kit receptor, actively participates in the organ reconstruction and fibrosis associated with various diseases, including kidney disease. However, it remains unclear whether SCF plays a role in kidney aging.

DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS

In the present study, we measured the serum SCF level, estimated glomerular filtration rate (eGFR), and other biological parameters in a Chinese Han group of 892 subjects, and explored the relationship between SCF level and renal function during aging; we sought to define novel biomarkers of kidney aging.

RESULTS

Multiple linear regression was used to select potential indicators of decline in renal function. Only age, SCF level, and 25% maximum expiratory flow (25% MEF) were significant predictors after redundancy analysis (|r| > 0.70 and P < 0.05). Multiple linear regression showed that the relationship among eGFR, SCF level, and age could be described as follows: eGFR = 154.486 - (0.846 × age) - (0.011 × SCF level).

CONCLUSIONS

We found no between-gender difference in the effect of SCF on kidney aging. In conclusion, the SCF level is an ideal biomarker of renal aging and may help to predict changes in eGFR during aging.

Isostructural metal-insulator transition in VO2

The metal-insulator transition in correlated materials is usually coupled to a symmetry-lowering structural phase transition. This coupling not only complicates the understanding of the basic mechanism of this phenomenon but also limits the speed and endurance of prospective electronic devices. We demonstrate an isostructural, purely electronically driven metal-insulator transition in epitaxial heterostructures of an archetypal correlated material, vanadium dioxide. A combination of thin-film synthesis, structural and electrical characterizations, and theoretical modeling reveals that an interface interaction suppresses the electronic correlations without changing the crystal structure in this otherwise correlated insulator. This interaction stabilizes a nonequilibrium metallic phase and leads to an isostructural metal-insulator transition. This discovery will provide insights into phase transitions of correlated materials and may aid the design of device functionalities.