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First report of Matryoshka RNA virus in an African-European migrant bird
Viruses are diverse biological entities found virtually in all environments on Earth. Their association with parasitic protozoans was shown in the late 1980’s, followed by evidence that these viruses can influence the treatment of infections as well as influence parasite virulence. Recently, Matryoshka RNA viruses (MaRNAV) were discovered in Plasmodium vivax infected patients in Malaysia, as well as in species of the closely related avian haemosporidian genera Leucocytozoon and Haemoproteus in Oceania and North America. However, they have not been reported in other continents so far. The aim of this study was thus to screen haemosporidian infected European birds (African migrants and residents) for the presence of MaRNAV. Whole blood samples from wild birds were collected in Lithuania in May 2023. Haemosporidian parasite infections were first assessed by microscopic examination and later confirmed via PCR. RNA was isolated and tested by Reverse Transcriptase (RT) PCR for the presence of MaRNAV. Of the 12 samples that were RT-PCR-positive, only one from a common whitethroat (Curruca communis) had a sequence with 63% similarity to MARNAV-2 found in Leucocytozoon infected birds from Oceania. Total RNA from this sample was sequenced, bioinformatically analyzed, and a new virus, MaRNAV-7, was identified. At the amino acid level, it is phylogenetically closely related to MaRNAV-2, MaRNAV-3 and MaRNAV-6 RdRp sequences, all found in Leucocytozoon infected birds. This is the first report of MaRNAV in an African-European haemosporidian infected bird, and a first step in understanding MaRNAV prevalence, distribution, and specificity. However, the effects that MaRNAV can have on the parasites, modulation of the host immune response and transmission rates remain unknown.
Health professionals’ competence for the provision of quality primary health care in Amhara region, Ethiopia
Background Though competent health professionals are essential for building strong and resilient health systems; there is a dearth of evidence on whether health professionals possess core competencies for providing quality primary health care in Ethiopia. Therefore, the aim of this study was to examine health professionals’ competence in the provision of quality primary health care in Amhara region, Ethiopia. Methods A mixed methods study design with pragmatic philosophical paradigm was conducted on, 846 (for quantitative) and 12 (for qualitative) selected, health professionals from June 1–July 30/2023. Health professionals’ competence was measured through six domains, adapted from the World Health Organization (WHO) global competency framework for universal health coverage. Quantitative and qualitative data were collected. Logistic regression modeling and thematic analysis were carried out. Results The response rate was 98%. As rated by themselves, only 116 (14%) health professionals were competent for all competencies. The rating for specific competency domains was slightly higher with a range of 21.7% (180) to 30.7% (255) of the professionals were competent in personal conduct and evidence informed practice domains, respectively. The qualitative findings support the competence gaps identified in health professionals’ survey. Educational status, training, taking licensure/ certificate of competence (COC) exam, training in public universities/colleges, high cumulative GPA and monthly salary above 10,000 ETB (177.84$) positively affected the rating of the competence. Conclusions The rate of health professional competence as judged by the health professionals themselves in the study area was very low. The qualitative findings also identified several competence problems. Progressive health professional development in the form of upward and in-service training, provision of licensure/COC exam, and learning in public universities/colleges positively impact professional competence. Therefore, the health and education systems together should strengthening upgrading and in-service training including CPD; licensure/COC exam; optimize the salary and strong regulation of private colleges.
Decoding <i>Pw1</i> Imprinting in the Postischemic Heart: A Novel Antifibrotic Strategy?
Heart Failure: A Century View, From Failure to Function
Stepwise Provisional Versus Systematic Dual-Stent Strategies for Treatment of True Left Main Coronary Bifurcation Lesions
BACKGROUND: The optimal coronary stenting technique for true left main bifurcation lesions is uncertain. EBC MAIN (European Bifurcation Club Left Main Trial) aimed to evaluate clinical outcomes of a stepwise provisional strategy compared with a systematic dual-stent approach. METHODS: EBC MAIN was a randomized, investigator-initiated, open-label, multicenter, parallel-group trial conducted across 35 hospitals in 11 European countries. A total of 467 participants undergoing percutaneous coronary intervention for unprotected true left main bifurcation lesions were randomly assigned to the stepwise provisional strategy (n=230) or an upfront dual-stent approach (n=237). The mean (SD) age was 71 (10) years and 23% of participants were women. The primary end point was a composite of major adverse cardiac events, defined as all-cause mortality, all myocardial infarction, or clinically driven target lesion revascularization. Events were adjudicated by an independent clinical events committee and all analyses were by the intention-to-treat principle. RESULTS: At 3 years, the primary end point occurred in 54 of 230 (23.5%) stepwise provisional and 70 of 237 (29.5%) dual-stent patients (hazard ratio, 0.75 [95% CI, 0.53–1.07]; P =0.11). There was no significant difference in all-cause mortality (10.0% versus 13.1%) or myocardial infarction (12.2% versus 11.0%). However, target lesion revascularization was significantly lower in the stepwise provisional group (8.3% versus 15.6%; hazard ratio, 0.50 [95% CI, 0.29–0.86]; P =0.013). In this population, the mean side vessel diameter by quantitative angiography was 2.9 mm, and median side vessel lesion length was 5 mm. Significant interactions were identified between the assigned bifurcation strategy and both side vessel diameter and lesion length with respect to the primary outcome ( P =0.009 and P =0.005, respectively), with smaller vessels (<3.25 mm diameter) and shorter lesions (<10 mm length) favoring the provisional approach. CONCLUSIONS: In a European population with true left main stem bifurcation coronary disease requiring intervention, there was no difference in major adverse cardiovascular events between stepwise provisional and systematic dual-stent strategies at 3 years. Target lesion revascularization was significantly less frequent with the stepwise provisional approach, which should be the default strategy for noncomplex left main bifurcation coronary intervention. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02497014.
Prevalence of Lipoprotein(a) Testing in a Contemporary Cohort
Activation of Imprinted Gene <i>PW1</i> Promotes Cardiac Fibrosis After Ischemic Injury
BACKGROUND: Cardiac fibrosis, characterized by excessive extracellular matrix (ECM) deposition in the myocardium, is an important target for heart disease treatments. Pw1 (paternally expressed gene 3) is an imprinted gene expressed from the paternal allele, and de novo purine biosynthesis (DNPB) is a crucial pathway for nucleotide synthesis. However, the roles of PW1 and DNPB in ECM production by cardiac fibroblasts during myocardial ischemia are not yet understood. METHODS: To induce myocardial damage, we performed left anterior descending coronary artery ligation. We generated Pw1 CreER-2A-eGFP and Pw1 2A-CreER knock-in mouse lines to evaluate the expression of the 2 Pw1 alleles in normal and injured hearts. Bisulfite sequencing was used to analyze the DNA methylation of the Pw1 imprinting control region. We identified the phosphoribosylformylglycinamidine synthase ( Pfas ) gene, encoding the DNPB enzyme PFAS, as a direct target of PW1 using chromatin immunoprecipitation sequencing and real-time quantitative polymerase chain reaction. The role of DNPB in ECM production and cardiac fibrosis after injury was examined in vitro using cultured cardiac fibroblasts and in vivo with Pfas -deficient mice. RESULTS: Our study demonstrates that myocardial infarction reduces DNA methylation at the imprinting control region of the maternally imprinted gene Pw1 , triggering a switch from monoallelic imprinting to biallelic expression of Pw1 in cardiac fibroblasts. In activated cardiac fibroblasts, increased Pw1 expression promotes purine biosynthesis and induces ECM production by transcriptionally activating the DNPB factor Pfas . We identified that DNPB is essential for ECM production in activated fibroblasts and that loss of Pfas in fibroblasts limits cardiac fibrosis and improves heart function after injury. CONCLUSIONS: This study demonstrates that Pw1 imprinting is disrupted after injury and reveals a novel role for the downstream target PFAS in ECM production and cardiac fibrogenesis. Targeting the PW1/PFAS signaling pathway presents a promising therapeutic strategy for improving cardiac repair after injury.
Long-Term Efficacy and Safety of Acoramidis in ATTR-CM: Initial Report From the Open-Label Extension of the ATTRibute-CM Trial
BACKGROUND: In the phase 3 randomized controlled study ATTRibute-CM (Efficacy and Safety of AG10 in Subjects With Transthyretin Amyloid Cardiomyopathy), acoramidis, a transthyretin stabilizer, demonstrated significant efficacy on the primary end point. Participants with transthyretin amyloid cardiomyopathy who completed ATTRibute-CM were invited to enroll in an open-label extension study (OLE). We report the efficacy and safety data of acoramidis in participants who completed ATTRibute-CM and enrolled in the ongoing OLE. METHODS: Participants who previously received acoramidis through month 30 in ATTRibute-CM continued to receive it (continuous acoramidis), and those who received placebo through month 30 were switched to acoramidis (placebo to acoramidis). Participants who received concomitant tafamidis in ATTRibute-CM were required to discontinue it to be eligible to enroll in the OLE. Clinical efficacy outcomes analyzed through month 42 included time to event for all-cause mortality (ACM) or first cardiovascular-related hospitalization (CVH), ACM alone, first CVH alone, ACM or recurrent CVH, change from baseline in NT-proBNP (N-terminal pro-B-type natriuretic peptide), 6-minute walk distance, serum transthyretin, and Kansas City Cardiomyopathy Questionnaire Overall Summary score. Safety outcomes were analyzed through month 42. RESULTS: Overall, 438 of 632 participants in ATTRibute-CM completed treatment, and 389 enrolled in the ongoing OLE (263 continuous acoramidis and 126 placebo to acoramidis). The hazard ratio for ACM or first CVH was 0.57 (95% CI, 0.46–0.72) at month 42 based on a stratified Cox proportional hazards model ( P <0.0001) favoring continuous acoramidis. Similar analyses were performed on ACM alone and first CVH alone, with hazard ratios of 0.64 (95% CI, 0.47–0.88) and 0.53 (95% CI, 0.41–0.69), respectively, at month 42. Treatment effects for NT-proBNP and 6-minute walk distance also favored continuous acoramidis. On initiation of open-label acoramidis in the placebo-to-acoramidis arm, there was a prompt increase in serum transthyretin. Quality of life assessed by Kansas City Cardiomyopathy Questionnaire Overall Summary score was well preserved in continuous-acoramidis participants compared with the placebo-to-acoramidis participants. No new clinically important safety issues were identified in this long-term evaluation. CONCLUSIONS: Early initiation and continuous use of acoramidis in the ATTRibute-CM study through month 42 of the ongoing OLE study were associated with sustained clinical benefits in a contemporary transthyretin amyloid cardiomyopathy cohort, with no clinically important safety issues newly identified. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04988386.
Rivaroxaban for 18 Months Versus 6 Months in Patients With Cancer and Acute Low-Risk Pulmonary Embolism: An Open-Label, Multicenter, Randomized Clinical Trial (ONCO PE Trial)
BACKGROUND: The optimal duration of anticoagulation therapy for patients with cancer and acute low-risk pulmonary embolism (PE) is clinically relevant, but evidence is lacking. Prolonged anticoagulation therapy could have a potential benefit for prevention of thrombotic events; however, it could also increase the risk of bleeding. METHODS: In a multicenter, open-label, adjudicator-blinded, randomized clinical trial at 32 institutions in Japan, we randomly assigned patients with cancer and acute low-risk PE of the simplified version of the Pulmonary Embolism Severity Index score of 1, in a 1:1 ratio, to receive either an 18-month or a 6-month rivaroxaban treatment. The primary end point was recurrent venous thromboembolism (VTE) at 18 months. The major secondary end point was major bleeding at 18 months according to the criteria of the International Society on Thrombosis and Hemostasis. The primary hypothesis was that an 18-month treatment was superior to a 6-month treatment in terms of the primary end point. RESULTS: From February 2021 to March 2023, 179 patients were randomized, and after the exclusion of one patient who withdrew consent, 178 were included in the intention-to-treat population: 89 patients in the 18-month rivaroxaban group and 89 in the 6-month rivaroxaban group. The mean age was 65.7 years; 47% of the patients were men, and 12% had symptoms of PE at baseline. The primary end point of recurrent VTE occurred in 5 of the 89 patients (5.6%) in the 18-month rivaroxaban group and in 17 of the 89 (19.1%) in the 6-month rivaroxaban group (odds ratio, 0.25 [95% CI, 0.09–0.72]; P =0.01). Among 22 recurrent VTE, 5 patients presented with a symptomatic recurrent VTE; recurrent PE occurred in 11 patients, including 2 with main and 4 with lobar PEs; and recurrent deep vein thrombosis was seen in 11 patients, including 3 with proximal deep vein thromboses. The major secondary end point of major bleeding occurred in 7 of the 89 patients (7.8%) in the 18-month rivaroxaban group and in 5 of the 89 patients (5.6%) in the 6-month rivaroxaban group (odds ratio, 1.43 [95% CI, 0.44–4.70]; P =0.55). CONCLUSIONS: In patients with cancer and acute low-risk PE of the simplified version of the Pulmonary Embolism Severity Index score of 1, the 18-month rivaroxaban treatment was superior to the 6-month rivaroxaban treatment with respect to recurrent VTE events. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04724460.
Letter by Teng et al Regarding Article, “LXRα Promotes Abdominal Aortic Aneurysm Formation Through UHRF1 Epigenetic Modification of miR-26b-3p”
Response by Guo et al to Letter Regarding Article, “LXRα Promotes Abdominal Aortic Aneurysm Formation Through UHRF1 Epigenetic Modification of miR-26b-3p”
Molecular patterns of matrix protein 1 (M1): A strong predictor of adaptive evolution in H9N2 avian influenza viruses
The H9N2 subtype of avian influenza virus (AIV) emerges as a significant member of the influenza A virus family. However, the varying degrees of epidemiological dominance among different lineages or clades of H9N2 AIVs have not been fully clarified. The matrix protein M1, a key structural component of the virion, plays a crucial role in maintaining the viral structure and lifecycle. To elucidate the intrinsic relationship between the genetic patterns of M1 and the adaptive dynamics of H9N2 AIVs, this study focused on the five major evolutionary patterns of M1 and conducted in vitro and in vivo investigations from the perspectives of vRNP release after viral uncoating, polymerase activity, mRNA and vRNA levels, the nuclear export of vRNPs, plasma membrane–binding capacity, proliferation capacity, growth competitiveness, and transmission potential. The results revealed a strong correlation between the epidemiological dominance of H9N2 AIVs and the specific patterns of M1, with M1 P5 standing out as particularly significant. This finding highlights the pivotal influence of the M1 gene patterns on the replication and transmission dynamics of H9N2 AIVs, thereby offering valuable insights into the mechanisms driving differences in adaptive evolution and shifts in epidemiological dominance within the H9N2 AIV population.
The synergistic effect of c-Myb hyperactivation and Pu.1 deficiency induces Pelger–Huët anomaly and promotes sAML
Approximately 30% of patients with myelodysplastic syndrome (MDS) progress to secondary acute myeloid leukemia (sAML) via accumulating gene mutations. Genomic analyses reveal a complex interplay among mutant genes, with co-occurring and mutually exclusive patterns. Hyperactivation of c-MYB and deficiency of PU.1 have been linked to myeloid disorders. We report a case of AML with concurrent PU.1 and c-MYB mutations, exhibiting early onset, high blast count, chemo-resistance, indicating high-risk features, along with elevated Pelger–Huët anomaly (PHA). However, the synergistic mechanism of c-MYB and PU.1 in sAML remains unclear. Using c-Myb-hyperactivation and Pu.1-deficient double-strain ( c-myb hyper ;pu.1 G242D/G242D ) zebrafish, we investigated MDS/sAML progression. Surprisingly, the double mutant exhibited a distinct type of neutrophil resembling clinical PHA cells and demonstrated a higher rate of MDS/sAML transformation. Further expression analysis revealed reduced lmnb1 expression in double-mutant zebrafish. Knockdown of lmnb1 resulted in PHA and increased blast cells, while overexpression of lmnb1 in c-myb hyper ;pu.1 G242D/G242D reduced PHA cell level. This suggests that c-Myb hyperactivation and Pu.1 deficiency synergistically reduce lmnb1 expression, inducing the development of PHA-like neutrophils and promoting MDS/sAML progression in zebrafish. Moreover, coadministration of cell cycle inhibitor cytarabine (Ara-C) and the differential inducer all-trans retinoic acid (ATRA) could effectively relieve the neutrophil expansion and PHA symptoms in c-myb hyper ;pu.1 G242D/G242D zebrafish. Our findings revealed that c-Myb hyperactivation and Pu.1 deficiency played a synergistic role in sAML development and suggests a phenotypic association between the emergence of PH-like cells and the transformation to sAML. Furthermore, c-myb hyper ;pu.1 G242D/G242D zebrafish might serve as a suitable sAML model for drug screening.
A numerically exact description of ultrafast vibrational decoherence in vibration-coupled electron transfer
Broadband pump–probe spectroscopy has been widely used to measure vibrational decoherence associated with the reaction coordinate in photoinduced ultrafast vibration-coupled electron transfer (VCET) reactions. These experiments provide insight into the interplay of intramolecular coordinates along the reaction coordinate. However, a general theoretical foundation for analyzing, and even for explaining rigorously, these data is lacking. In this work, we study vibrational decoherence in a model VCET reaction using the nearly exact time-dependent density matrix renormalization group simulation method. We explore how analyzing the density matrix with quantum information measures can help elucidate the evolution of vibrational coherence in simulations of dynamics. We examine how vibrational coherence is affected by electron transfer on the timescale of approximately 100 femtoseconds. Our results suggest that electron transfer, in the nonadiabatic model, changes the vibrational equilibrium position abruptly—an example of a “quantum quench” event. This explains the concomitant vibrational decoherence. We find that abrupt vibrational decoherence can be mitigated by wavepacket motion occurring on the timescale of the electron transfer.
Long-term B cell memory emerges at uniform relative rates in the human immune response
B cells generate pathogen-specific antibodies and play an essential role in providing adaptive protection against infection. Antibody genes are modified in evolutionary processes acting on the B cell populations within an individual. These populations proliferate, differentiate, and migrate to long-term niches in the body. However, the dynamics of these processes in the human immune system are primarily inferred from mouse studies. We addressed this gap by sequencing the antibody repertoire and transcriptomes from single B cells in four immune-rich tissues from six individuals. We find that B cells descended from the same pre-B cell (“lineages”) often colocalize within the same tissue, with the bone marrow harboring the largest excess of lineages without representation in other tissues. Within lineages, cells with different levels of somatic hypermutation are uniformly distributed among tissues and functional states. This suggests that the relative probabilities of localization and differentiation outcomes change negligibly during affinity maturation, and quantitatively agrees with a simple dynamical model of B cell differentiation. While lineages strongly colocalize, we find individual B cells nevertheless appear to make independent differentiation decisions. Proliferative antibody-secreting cells, however, deviate from these global patterns. These cells are often clonally expanded, their clones appear universally distributed among all sampled organs, and form lineages with an excess of cells of the same type. Collectively, our findings show the limits of peripheral blood monitoring of the immune repertoire, and provide a probabilistic model of the dynamics of antibody memory formation in humans.
Defects induce phase transition from dynamic to static rippling in graphene
Two-dimensional (2D) materials display nanoscale dynamic ripples that significantly impact their properties. Defects within the crystal lattice are the elementary building blocks to tailor the material’s morphology. While some studies have explored the link between defective structures and rippling dynamics in 2D materials, a comprehensive understanding of this relationship has yet to be achieved. Here, we address this using machine learning-driven molecular dynamics simulations. Specifically, we find that above a critical concentration of defects, free-standing graphene sheets undergo a dynamic transition from freely propagating to static ripples. Our computational approach captures the dynamics with atomic resolution, and reveals that the transition is driven by elastic interactions between defects. The strength of these interactions is found to vary across defect types and we identify a unifying set of principles driving the dynamic-to-static transition in 2D materials. Our work not only rationalizes puzzling experimental results for defective 2D materials, but also paves the way to design two-dimensional devices with tailored rippling dynamics. These insights could lay the foundations for a class of disorder-based catalytic and interfacial materials.
A degenerate telomerase RNA directs telomeric DNA synthesis in lepidopteran insects
Telomerase elongates telomeres to maintain chromosome stability in most eukaryotes. Despite extensive studies across eukaryotic kingdoms, the telomerase holoenzyme in arthropods remains poorly understood. In this study, we purify the telomerase ribonucleoprotein complex from the lepidopteran insect Spodoptera frugiperda (fall armyworm) and identify a copurified 135-nucleotide telomerase RNA (TR) component. This miniature S. frugiperda TR (sfTR), the smallest TR known to date, retains a universal pseudoknot structure and a structurally defined template. Despite its small size, sfTR assembles with the recombinant S. frugiperda telomerase reverse transcriptase (sfTERT) protein in vivo to reconstitute telomerase activity for the synthesis of insect telomeric DNA repeats (TTAGG)n. The sfTR gene, like other animal TR genes, features an snRNA-type RNA polymerase II promoter. Uniquely, the sfTR transcript harbors a 5′-7-methylguanosine (M 7 G) cap, as opposed to the more typical snRNA-type 2,2,7-trimethylguanosine (TMG) cap. The difference in 5′-cap is likely because sfTR lacks the H/ACA snoRNA biogenesis domain necessary for cap hypermethylation. Moreover, sfTR also lacks the CR4/5 regulatory domain that is indispensable in vertebrate TRs for telomerase activity. This degenerate sfTR complements an enigmatic sfTERT that is missing certain telomerase-specific elements yet catalytically active in the absence of sfTR. Thus, insects have evolved a simplified telomerase, consisting of a small noncoding RNA that retains only minimal attributes essential for telomerase function. The simplified insect telomerase demonstrates a plausible evolutionary pathway for the emergence of telomerase ribonucleoprotein complex, arising from an ancient reverse transcriptase associated with a simple templating RNA component in early eukaryotes.
Disruption of G3BP1 granules promotes mammalian CNS and PNS axon regeneration
Depletion or inhibition of core stress granule proteins, G3BP1 in mammals and TIAR-2 in Caenorhabditis elegans , increases the growth of spontaneously regenerating axons. Inhibition of G3BP1 by expression of its acidic or “B-domain” accelerates axon regeneration after nerve injury, bringing a potential therapeutic strategy for peripheral nerve repair. Here, we asked whether G3BP1 inhibition is a viable strategy to promote regeneration in injured mammalian central nervous system (CNS) where axons do not regenerate spontaneously. G3BP1 B-domain expression was found to promote axon regeneration in the transected spinal cord provided with a permissive peripheral nerve graft (PNG) as well as in crushed optic nerve. Moreover, a cell-permeable peptide (CPP) to a subregion of B-domain (rodent G3BP1 amino acids 190 to 208) accelerated axon regeneration after peripheral nerve injury and promoted regrowth of reticulospinal axons into the distal transected spinal cord through a bridging PNG. G3BP1 CPP promoted axon growth from rodent and human neurons cultured on permissive substrates, and this function required alternating Glu/Asp-Pro repeats that impart a unique predicted tertiary structure. The G3BP1 CPP disassembles axonal G3BP1, G3BP2, and FMRP, but not FXR1, granules and selectively increases axonal protein synthesis in cortical neurons. These studies identify G3BP1 granules as a key regulator of axon growth in CNS neurons and demonstrate that disassembly of these granules promotes retinal axon regeneration in injured optic nerve and reticulospinal axon elongation into permissive environments after CNS injury. This work highlights G3BP1 granule disassembly as a potential therapeutic strategy for enhancing axon growth and neural repair.