Registered clinical trials investigating treatment with cell-derived extracellular vesicles: a scoping review.

BACKGROUND AIMS: Interest in cell-based therapy using extracellular vesicles (EVs) is intensifying, building upon promising preclinical research and a handful of published clinical studies. Registered clinical trials remain small, heterogeneous in design and underpowered to determine safety and efficacy on their own. A scoping review of registered studies can identify opportunities to pool data and perform meta-analysis. METHODS: Registered trials were identified by searching clinical trial databases (Clinicaltrials.gov, the World Health Organization International Clinical Trials Registry Platform and the Chinese Clinical Trial Registry) on June 10, 2022. RESULTS: Seventy-three trials were identified and included for analysis. Mesenchymal stromal cells (MSCs) were the most common cell type from which EVs were derived (49 studies, 67%). Among the 49 identified MSC-EV studies, 25 were controlled trials (51%) with a combined total of 3094 participants anticipated to receive MSC-derived EVs (2225 in controlled studies). Although EVs are being administered to treat a broad range of conditions, trials treating patients with coronavirus disease-2019 and/or acute respiratory distress syndrome were observed most commonly. Despite heterogeneity between studies, we anticipate that at least some of the studies could be combined in meaningful meta-analysis and that a combined sample size of 1000 patients would provide the ability to detect a ≥5% difference in mortality with MSC-EVs compared to controls and could be achieved by December 2023. CONCLUSIONS: This scoping review identifies potential barriers that may stall clinical translation of EV-based treatment, and our analysis calls for more standardized product characterization, use of quantifiable product quality attributes and consistent outcome reporting in future clinical trials.

The Willingness to get Vaccinated Against SARS-CoV-2 Virus among Southeast Asian Countries: Does the Vaccine Brand Matter?

The current study uses data surveyed with 2,500 respondents during August and September 2021 in Vietnam, Indonesia, the Philippines and Malaysia to examine the willingness to get vaccinated against SARS-CoV-2 virus with six COVID-19 vaccines. The willingness to get vaccinated varies according to the vaccine brands and selected influential factors. Particularly, the percentage of respondents who are willing to get vaccinated with Pfizer, Moderna and AstraZeneca dominates that of those who are willing to get vaccinated with Sinopharm, Janssen and Sputnik V vaccines. Results generated from the binary logistic regressions show that the impact of the selected influential factors on the willingness to get vaccinated varies in terms of magnitude and direction, and depending on the vaccine brands. The results indicate that additional scientific evidence on the efficacy and safety of the vaccines is essential for the respondents to decide whether to vaccinate or not. Such evidence can be made available in multiple formats and provided through appropriate channels and vaccination communication campaigns.

The Willingness of Parents to Vaccinate Their Children Aged from Five to under Twelve Years with COVID-19 Vaccines between February and March 2022 in Vietnam.

The current study used data surveyed with 5357 parents/guardians (parents would be used to represent both 'parents' and 'guardians' hereafter) between February and March 2022 in Vietnam to examine their willingness to vaccinate their children with current COVID-19 vaccines. It applied the multinomial logistic regression model to examine the association between the willingness of parents and selected influential factors. In addition, the reasons that made parent hesitant or unwilling to vaccinate their children were investigated. Moreover, it identified parents' preferences for vaccine origins. Approximately, 75.4% of the parents were willing, 21.3% were hesitant and 3.3% were unwilling to vaccinate their children. The most common reasons that made the parents hesitant or unwilling to vaccinate their children were their concerns about the vaccine safety, efficacy and immunity. The most and the second most preferred vaccines were those developed/originated in the US and EU, respectively. Parents who were more likely to vaccinate their children included those whose children were insured, who regularly vaccinated their children, who belonged to the vaccine priority groups, who possessed sufficient knowledge about the ways to prevent the virus or about the herd immunity, and who perceived that their children might be infected with the virus and whose children were afraid of needles. Parents who were less likely to vaccinate their children included those who were the family main income source, who had savings, and who had tertiary education or higher.

Savior Siblings Might Rescue Fetal Lethality But Not Adult Lymphoma in Irf2bp2-Null Mice.

Interferon regulatory factor 2 binding protein 2 (Irf2bp2), a co-repressor of Irf2, is required for fetal hepatic erythropoiesis through the expansion of erythromyeloid progenitors. Mice with germline ablation of the entire Irf2bp2 transcript produced no viable Irf2bp2-null pups in first litters. In subsequent litters, fewer than 1/3 of the expected Irf2bp2-null pups were born and half survived to adulthood. As in humans with somatic mutations in IRF2BP2, adult Irf2bp2-null mice developed lymphoma. Transcriptome profiling of liver, heart, and skeletal muscle from Irf2bp2-null adult mice revealed a predominant upregulation of interferon-responsive genes. Of interest, hematopoietic stem cell-enriched transcription factors (Etv6, Fli1, Ikzf1, and Runx1) were also elevated in Irf2bp2-null livers. Intriguingly, Irf2bp2-positive myeloid (but not lymphoid) cells were detected in the livers of adult Irf2bp2-null mice. In female Irf2bp2-null mice, these cells carried a Y chromosome while in male Irf2bp2-null livers, no cells with Barr bodies (inactivated X chromosomes) were detected, indicating that Irf2bp2-positive erythromyeloid cells might be acquired only from male siblings of prior litters by transmaternal microchimerism. These cells likely rescue the deficit in fetal erythropoiesis, but not adult-onset lymphomagenesis, caused by Irfb2p2 ablation.

Efficacy, safety, and immunogenicity of an inactivated, adjuvanted enterovirus 71 vaccine in infants and children: a multiregion, double-blind, randomised, placebo-controlled, phase 3 trial.

BACKGROUND: Children are susceptible to severe or fatal enterovirus 71 (EV71) infections. We aimed to evaluate the efficacy, safety, and immunogenicity of EV71vac, an aluminium phosphate-adjuvanted inactivated EV71 vaccine in children aged 2-71 months. METHODS: We did a randomised, double-blinded, placebo-controlled, phase 3 trial at five hospitals in Taiwan and two in Vietnam. Children aged 2-71 months were stratified by country and age, and randomly assigned (1:1) to receive two doses of EV71vac or placebo via intramuscular injection 56 days apart. Children aged 2-23 months received a third booster dose on day 366. The primary endpoint was the clinical efficacy of the total vaccinated cohort against EV71-associated diseases during the follow-up period, from 14 days after the second dose to when 15 cases of EV71 infections were confirmed in the per-protocol population. Our safety analysis included all participants who received at least one dose of EV71vac. This trial is registered with ClinicalTrials.gov, NCT03865238, and is complete. FINDINGS: Between April 23 and Dec 25, 2019, of 3663 children assessed, 3061 were randomly assigned, of whom 3049 were vaccinated: 1521 children in the EV71vac group and 1528 in the placebo group. By May 20, 2021, our primary efficacy analysis included 2959 children, with 1476 children in the EV71vac group and 1483 children in the placebo group. The vaccine efficacy of EV71vac was 96·8% (95% CI 85·5-100) against EV71 associated diseases (p<0·0001). The percentage of participants who reported solicited adverse events were similar in both groups: 865 (56·9%) in the EV71vac group and 852 (55·8%) in the placebo group. Almost all reported solicited adverse events were mild and self-limited. INTERPRETATION: EV71vac is safe, well-tolerated, and highly effective in preventing EV71 associated diseases in children aged 2-71 months. FUNDING: Medigen Vaccine Biologics and A+ Industrial Innovative R&D Program of the Ministry of Economic Affairs, Taiwan.

COVID-19 Vaccine Acceptance among ASEAN Countries: Does the Pandemic Severity Really Matter?

The current study uses data surveyed between August and September 2021 in four ASEAN (Association of South East Asian Nations) countries to identify drivers of COVID-19 vaccine acceptance with different levels of the pandemic severity. It also examines the impact of the drivers on vaccine acceptance. The results show that the number of respondents who accept vaccines significantly dominates that of those who do not. In addition, the number of respondents who get the vaccine if the pandemic becomes more severe dominates that of those if it becomes less severe. Results generated from the logistic regressions show that the impact of the drivers on the COVID-19 vaccine acceptance with different levels of the pandemic severity varies in terms of magnitude and direction. Practical recommendations are made based on the findings.

IRF2BP2 3'UTR Polymorphism Increases Coronary Artery Calcification in Men.

Interferon regulatory factor 2 binding protein 2 (IRF2BP2) suppresses the innate inflammatory response of macrophages. A 9-nucleotide deletion (rs3045215) in the 3' untranslated region (3'-UTR) of human IRF2BP2 mRNA confers risk of coronary artery disease (CAD) in the Ottawa Heart Genomics Study (OHGS). Here, we sought to identify regulatory mechanisms that may contribute to this risk. We tested how lipopolysaccharides (LPS) affects IRF2BP2 expression in human THP-1 macrophages and primary aortic smooth muscle cells (HAoSMC) genotyped for the deletion allele. Both cell types are implicated in coronary atherosclerosis. We also examined how the deletion affects interaction with RNA binding proteins (RBPs) to regulate IRF2BP2 expression. LPS altered allele-specific binding of RBPs in RNA gel shift assays with the THP-1 macrophage protein extracts. The RBP ELAVL1 suppressed the expression of a luciferase reporter carrying the 3'UTR of IRF2BP2 with the deletion allele. Other RBPs AUF1 or KHSRP did not confer such allele specific regulation. Since it is co-inherited with a risk variant for osteoporosis, a condition tied to arterial calcification, we examined the association of the deletion allele with coronary artery calcification in individuals who had undergone computed tomography angiography in the OHGS. In 323 individuals with a minimal burden of atherosclerosis (<30% coronary stenosis) and 138 CAD cases (>50% stenosis), Mendelian randomization revealed that the rs3045215 deletion allele significantly increased coronary artery calcification in men with minimal coronary stenosis. Thus, not only does the rs3045215 deletion allele predict atherosclerosis, but it also predisposes to early-onset calcification in men.

Redondoviridae: High Prevalence and Possibly Chronic Shedding in Human Respiratory Tract, But No Zoonotic Transmission.

Redondoviridae is a recently discovered DNA virus family consisting of two species, vientovirus and brisavirus. Here we used PCR amplification and sequencing to characterize redondoviruses in nasal/throat swabs collected longitudinally from a cohort of 58 individuals working with animals in Vietnam. We additionally analyzed samples from animals to which redondovirus DNA-positive participants were exposed. Redondoviruses were detected in approximately 60% of study participants, including 33% (30/91) of samples collected during episodes of acute respiratory disease and in 50% (29/58) of baseline samples (with no respiratory symptoms). Vientovirus (73%; 24/33) was detected more frequently in samples than brisaviruses (27%; 9/33). In the 23 participants with at least 2 redondovirus-positive samples among their longitudinal samples, 10 (43.5%) had identical redondovirus replication-gene sequences detected (sampling duration: 35-132 days). We found no identical redondovirus replication genes in samples from different participants, and no redondoviruses were detected in 53 pooled nasal/throat swabs collected from domestic animals. Phylogenetic analysis described no large-scale geographical clustering between viruses from Vietnam, the US, Spain, and China, indicating that redondoviruses are highly genetically diverse and have a wide geographical distribution. Collectively, our study provides novel insights into the Redondoviridae family in humans, describing a high prevalence, potentially associated with chronic shedding in the respiratory tract with lack of evidence of zoonotic transmission from close animal contacts. The tropism and potential pathogenicity of this viral family remain to be determined.

Exploring Cancer Patients' Experiences of an Online Mindfulness-Based Program: A Qualitative Investigation.

OBJECTIVE: Chronic neuropathic pain (CNP) is a common condition cancer survivors experience. Mindfulness training may be one approach to address the psychosocial factors associated with CNP. The purpose of this study was to understand patients' experiences in an 8-week online mindfulness-based program (MBP), including techniques and skills learned and applied, barriers to practice, and research experiences. METHODS: Nineteen participants who were part of a randomized controlled trial consented to participate in a telephone interview or submit written responses via email post-course. Interviews were transcribed and analyzed using the principles of Applied Thematic Analysis (ATA). RESULTS: Predominant themes identified in participant interviews included (1) common humanity, (2) convenience, (3) teacher resonance, (4) perceived relaxation and calm, (5) pain and stress management, (6) half-day session, and (7) mindful breathing. Participants also identified helpful strategies learned and implemented from the course, as well as barriers to practice, and key components of their experiences in a randomized controlled trial, including a sense of disconnection post-course and needing continued ongoing sessions, and the importance of the facilitators' skills in creating a comfortable and supportive space. CONCLUSIONS: An online group-based MBP may offer a more accessible resource and form of psychosocial intervention and support for cancer survivors living with CNP. Furthermore, the need and consideration for implementing ongoing group maintenance sessions to minimize participants' feelings of disconnect and abandonment post-course and post-study are warranted in future MBP development.

Annulus-Sparing Tetralogy of Fallot Repair: Low Risk and Benefits to Right Ventricular Geometry.

BACKGROUND: Annulus-sparing repair of tetralogy of Fallot (TOF) carries a potential increased risk of reoperation for restenosis and unproven benefits on right ventricular (RV) geometry. METHODS: Primary TOF repairs (n = 434) between 2000 and 2012 were studied using risk-adjusted parametric techniques. Progression of cardiac dimensions was analyzed using repeated measures regression using reports of all 2,103 echocardiograms undertaken throughout the study period, to a maximum follow-up of 13.7 years. RESULTS: Repair was at a mean age of 180 days: AS approach in 296 (68%) patients; and transannular patch in 138 (32%). Intraoperative revisions (for residual stenosis) were required in 135 patients (29%). There have been 4 deaths (survival 99%). Surgical reoperation for recurrent right ventricular outflow tract stenosis was occasionally required in both groups at comparable rates (transannular patch, 5 of 136 [4%]; annulus-sparing repair, 14 of 296 [5%]; p = 0.83). Larger increases in RV end-diastolic dimensions were evident in transannular patch patients versus annulus-sparing repair patients (p < 0.0001). Other risks for RV dilation included worse grade of postoperative pulmonary regurgitation, larger right ventricular end-diastolic dimension at the time of diagnosis, and higher operative weight (all p < 0.0001). Factors associated with successful annulus-sparing repair included (1) pulmonary annulus greater than 7 mm, right ventricular end-diastolic dimension greater than 1.2 cm, and tricuspid annulus greater than 1.4 cm (all preoperatively); and (2) right ventricular outflow tract diameter greater than 10 mm and right ventricular systolic pressure less than 50 mm Hg (both intraoperatively after repair). CONCLUSIONS: Pursuit of annulus-sparing repair strategies can lower the use of transannular patch to approximately 30% with low risk of reoperation for the patient. Annulus-sparing repair is associated with significantly reduced long-term RV dilation. Pulmonary valve enlargement to approximately 10 mm and right ventricular systolic pressure less than 50 mm Hg during annulus-sparing repair are associated with low risk of recurrent stenosis.

You're the Flight Surgeon. Arrythmogenic right ventricular cardiomyopathy.

Duong A. You're the flight surgeon: arrythmogenic right ventricular cardiomyopathy. Aerosp Med Hum Perform. 2015; 86(8):756-759.

Population structure and evolution of pathogenicity of Yersinia pseudotuberculosis.

Yersinia pseudotuberculosis is an enteric human pathogen but is widespread in the environment. Pathogenicity is determined by a number of virulence factors, including the virulence plasmid pYV, the high-pathogenicity island (HPI), and the Y. pseudotuberculosis-derived mitogen (YPM), a superantigen. The presence of the 3 virulence factors varies among Y. pseudotuberculosis isolates. We developed a multilocus sequence typing (MLST) scheme to address the population structure of Y. pseudotuberculosis and the evolution of its pathogenicity. The seven housekeeping genes selected for MLST were mdh, recA, sucA, fumC, aroC, pgi, and gyrB. An MLST analysis of 83 isolates of Y. pseudotuberculosis, representing 19 different serotypes and six different genetic groups, identified 61 sequence types (STs) and 12 clonal complexes. Out of 26 allelic changes that occurred in the 12 clonal complexes, 13 were mutational events while 13 were recombinational events, indicating that recombination and mutation contributed equally to the diversification of the clonal complexes. The isolates were separated into 2 distinctive clusters, A and B. Cluster A is the major cluster, with 53 STs (including Y. pestis strains), and is distributed worldwide, while cluster B is restricted to the Far East. The YPM gene is widely distributed on the phylogenetic tree, with ypmA in cluster A and ypmB in cluster B. pYV is present in cluster A only but is sporadically absent in some cluster A isolates. In contrast, an HPI is present only in a limited number of lineages and must be gained by lateral transfer. Three STs carry all 3 virulence factors and can be regarded as high-pathogenicity clones. Isolates from the same ST may not carry all 3 virulence factors, indicating frequent gain or loss of these factors. The differences in pathogenicity among Y. pseudotuberculosis strains are likely due to the variable presence and instability of the virulence factors.