Improved production of the antidiabetic metabolite montbretin A in Nicotiana benthamiana: discovery, characterization, and use of Crocosmia shikimate shunt genes.

The plant-specialized metabolite montbretin A (MbA) is being developed as a new treatment option for type-2 diabetes, which is among the ten leading causes of premature death and disability worldwide. MbA is a complex acylated flavonoid glycoside produced in small amounts in below-ground organs of the perennial plant Montbretia (Crocosmia × crocosmiiflora). The lack of a scalable production system limits the development and potential application of MbA as a pharmaceutical or nutraceutical. Previous efforts to reconstruct montbretin biosynthesis in Nicotiana benthamiana (Nb) resulted in low yields of MbA and higher levels of montbretin B (MbB) and montbretin C (MbC). MbA, MbB, and MbC are nearly identical metabolites differing only in their acyl moieties, derived from caffeoyl-CoA, coumaroyl-CoA, and feruloyl-CoA, respectively. In contrast to MbA, MbB and MbC are not pharmaceutically active. To utilize the montbretia caffeoyl-CoA biosynthesis for improved MbA engineering in Nb, we cloned and characterized enzymes of the shikimate shunt of the general phenylpropanoid pathway, specifically hydroxycinnamoyl-CoA: shikimate hydroxycinnamoyl transferase (CcHCT), p-coumaroylshikimate 3'-hydroxylase (CcC3'H), and caffeoylshikimate esterase (CcCSE). Gene expression patterns suggest that CcCSE enables the predominant formation of MbA, relative to MbB and MbC, in montbretia. This observation is supported by results from in vitro characterization of CcCSE and reconstruction of the shikimate shunt in yeast. Using CcHCT together with montbretin biosynthetic genes in multigene constructs resulted in a 30-fold increase of MbA in Nb. This work advances our understanding of the phenylpropanoid pathway and features a critical step towards improved MbA production in bioengineered Nb.

iPSC-Based Modeling of Variable Clinical Presentation in Hypertrophic Cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac disease and a frequent cause of heart failure and sudden cardiac death. Our understanding of the genetic bases and pathogenic mechanisms underlying HCM has improved significantly in the recent past, but the combined effect of various pathogenic gene variants and the influence of genetic modifiers in disease manifestation are very poorly understood. Here, we set out to investigate genotype-phenotype relationships in 2 siblings with an extensive family history of HCM, both carrying a pathogenic truncating variant in the MYBPC3 gene (p.Lys600Asnfs*2), but who exhibited highly divergent clinical manifestations. METHODS: We used a combination of induced pluripotent stem cell (iPSC)-based disease modeling and CRISPR (clustered regularly interspersed short palindromic repeats)/Cas9 (CRISPR-associated protein 9)-mediated genome editing to generate patient-specific cardiomyocytes (iPSC-CMs) and isogenic controls lacking the pathogenic MYBPC3 variant. RESULTS: Mutant iPSC-CMs developed impaired mitochondrial bioenergetics, which was dependent on the presence of the mutation. Moreover, we could detect altered excitation-contraction coupling in iPSC-CMs from the severely affected individual. The pathogenic MYBPC3 variant was found to be necessary, but not sufficient, to induce iPSC-CM hyperexcitability, suggesting the presence of additional genetic modifiers. Whole-exome sequencing of the mutant carriers identified a variant of unknown significance in the MYH7 gene (p.Ile1927Phe) uniquely present in the individual with severe HCM. We finally assessed the pathogenicity of this variant of unknown significance by functionally evaluating iPSC-CMs after editing the variant. CONCLUSIONS: Our results indicate that the p.Ile1927Phe variant of unknown significance in MYH7 can be considered as a modifier of HCM expressivity when found in combination with truncating variants in MYBPC3. Overall, our studies show that iPSC-based modeling of clinically discordant subjects provides a unique platform to functionally assess the effect of genetic modifiers.

Self-Consistent Field Approach for the Variational Quantum Eigensolver: Orbital Optimization Goes Adaptive.

We present a self-consistent field (SCF) approach within the adaptive derivative-assembled problem-tailored ansatz variational quantum eigensolver (ADAPT-VQE) framework for efficient quantum simulations of chemical systems on near-term quantum computers. To this end, our ADAPT-VQE-SCF approach combines the idea of generating an ansatz with a small number of parameters, resulting in shallow-depth quantum circuits with a direct minimization of an energy expression that is correct to second order with respect to changes in the molecular orbital basis. Our numerical analysis, including calculations for the transition-metal complex ferrocene [Fe (C5H5)2], indicates that convergence in the self-consistent orbital optimization loop can be reached without a considerable increase in the number of two-qubit gates in the quantum circuit by comparison to a VQE optimization in the initial molecular orbital basis. Moreover, the orbital optimization can be carried out simultaneously within each iteration of the ADAPT-VQE cycle. ADAPT-VQE-SCF thus allows us to implement a routine analogous to the complete active space SCF, a cornerstone of state-of-the-art computational chemistry, in a hardware-efficient manner on near-term quantum computers. Hence, ADAPT-VQE-SCF paves the way toward a paradigm shift for quantitative quantum-chemistry simulations on quantum computers by requiring fewer qubits and opening up for the use of large and flexible atomic orbital basis sets in contrast to earlier methods that are predominantly based on the idea of full active spaces with minimal basis sets.

Implementing a pilot study of COVID-19 self-testing in high-risk populations and remote locations: results and lessons learnt.

BACKGROUND: Rapid antigen-detection tests for SARS-CoV-2 self-testing represent a useful tool for pandemic control and expanding access to community-level case screening. COVID-19 self-tests have been extensively used in high-income countries since 2021; however, their introduction and programmatic implementation in low- and middle-income countries was delayed. We aimed to identify and continuously improve a weekly COVID-19 self-testing model among staff at healthcare facilities and schools. METHODS: This mixed-methods, observational prospective study was conducted in 5 healthcare centres and 24 schools in Georgia, between June and December 2022. The study comprised the integration of COVID-19 self-testing into the national mandatory testing programme for high-risk groups, with primary distribution of self-tests among staff performed weekly, plus secondary distribution to their household members. These use cases were selected because NCDC was seeking to strengthen their already strong weekly testing programme, by investigating self-testing to ease the burden of testing in the healthcare system. Online surveys and semi-structured interviews were used for data collection. RESULTS: In total, 2156 participants were enrolled (1963 female, 72%). At baseline and mid- and end-points, 88%, 97% and 99%, respectively, of participants agreed/strongly agreed they would self-test. Similarly, the majority were willing to report their self-testing results (88%, 98% and 96% at baseline and mid- and end-points, respectively). Weekly reporting of test results to the national COVID-19 database was high during all the implementation. There were 622 COVID-19 positive results reported, and linked to care, from 601 individuals (282 participants and 319 household members). Findings from qualitative interviews showed great satisfaction with self-testing for its convenience, ease of use, trust in the results, no need to travel for diagnostics, and increased perception of safety. CONCLUSIONS: Our findings contribute to the evidence-base regarding self-testing strategies conducted via workplaces and secondary distribution to households. Willingness to perform a COVID-19 self-test increased after implementation. This pilot enhanced pandemic preparedness through expansion of the national self-testing reporting system, development of communications materials, changes in the national legal framework and coordination mechanisms, and improved perceptions around self-care in the community. The lessons learnt can inform operational aspects of the introduction and scale-up of self-care strategies.

Scaling up real networks by geometric branching growth.

Real networks often grow through the sequential addition of new nodes that connect to older ones in the graph. However, many real systems evolve through the branching of fundamental units, whether those be scientific fields, countries, or species. Here, we provide empirical evidence for self-similar growth of network structure in the evolution of real systems-the journal-citation network and the world trade web-and present the geometric branching growth model, which predicts this evolution and explains the symmetries observed. The model produces multiscale unfolding of a network in a sequence of scaled-up replicas preserving network features, including clustering and community structure, at all scales. Practical applications in real instances include the tuning of network size for best response to external influence and finite-size scaling to assess critical behavior under random link failures.

Quasi-Diamond Platelet-Shaped Zinc Oxide Nanostructures Display Enhanced Antibacterial Activity.

The current study compares the antibacterial activity of zinc oxide nanostructures (neZnO). For this purpose, two bacterial strains, Escherichia coli (ATCC 4157) and Staphylococcus aureus (ATCC 29213) were challenged in room light conditions with the aforementioned materials. Colloidal and hydrothermal methods were used to obtain the quasi-round and quasi-diamond platelet-shape nanostructures. Thus, the oxygen vacancy (VO ) effects on the surface of neZnO are also considered to assess its effects on antibacterial activity. The neZnO characterization was achieved by X-ray diffraction (XRD), a selected area electron diffraction (SAED) and Raman spectroscopy. The microstructural effects were monitored by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Furthermore, optical absorption ultraviolet visible spectrophotometry (UV-Vis) and X-ray photoelectron spectroscopy (XPS) analyses complement the physical characterization of these nanostructures; neZnO caused 50 % inhibition (IC50 ) at concentrations from 0.064 to 0.072 mg/mL for S. aureus and from 0.083 to 0.104 mg/mL for E. coli, indicating an increase in activity against S. aureus compared to E. coli. Consequently, quasi-diamond platelet-shaped nanostructures (average particle size of 377.6±10 nm) showed enhanced antibacterial activity compared to quasi-round agglomerated particles (average size of 442.8±12 nm), regardless of Vo presence or absence.

Immune cell kinetics and antibody response in COVID-19 patients with low-count monoclonal B-cell lymphocytosis.

Low-count monoclonal B-cell lymphocytosis (MBLlo ) has been associated with an underlying immunodeficiency and has recently emerged as a new risk factor for severe COVID-19. Here, we investigated the kinetics of immune cell and antibody responses in blood during COVID-19 of MBLlo versus non-MBL patients. For this study, we analyzed the kinetics of immune cells in blood of 336 COVID-19 patients (74 MBLlo and 262 non-MBL), who had not been vaccinated against SARS-CoV-2, over a period of 43 weeks since the onset of infection, using high-sensitivity flow cytometry. Plasma levels of anti-SARS-CoV-2 antibodies were measured in parallel by ELISA. Overall, early after the onset of symptoms, MBLlo COVID-19 patients showed increased neutrophil, monocyte, and particularly, plasma cell (PC) counts, whereas eosinophil, dendritic cell, basophil, and lymphocyte counts were markedly decreased in blood of a variable percentage of samples, and with a tendency toward normal levels from week +5 of infection onward. Compared with non-MBL patients, MBLlo COVID-19 patients presented higher neutrophil counts, together with decreased pre-GC B-cell, dendritic cell, and innate-like T-cell counts. Higher PC levels, together with a delayed PC peak and greater plasma levels of anti-SARS-CoV-2-specific antibodies (at week +2 to week +4) were also observed in MBLlo patients. In summary, MBLlo COVID-19 patients share immune profiles previously described for patients with severe SARS-CoV-2 infection, associated with a delayed but more pronounced PC and antibody humoral response once compared with non-MBL patients.

Real-life evidence about the use of intravenous brivaracetam in urgent seizures: The BRIV-IV study.

PURPOSE: Urgent seizures are a medical emergency for which new therapies are still needed. This study evaluated the use of intravenous brivaracetam (IV-BRV) in an emergency setting in clinical practice. METHODS: BRIV-IV was a retrospective, multicenter, observational study. It included patients ≥18 years old who were diagnosed with urgent seizures (including status epilepticus (SE), acute repetitive seizures, and high-risk seizures) and who were treated with IV-BRV according to clinical practice in 14 hospital centers. Information was extracted from clinical charts and included in an electronic database. Primary effectiveness endpoints included the rate of IV-BRV responder patients, the rate of patients with a sustained response without seizure relapse in 12 h, and the time between IV-BRV administration and clinical response. Primary safety endpoints were comprised the percentage of patients with adverse events and those with adverse events leading to discontinuation. RESULTS: A total of 156 patients were included in this study. The mean age was 57.7 ± 21.5 years old with a prior diagnosis of epilepsy for 57.1% of patients. The most frequent etiologies were brain tumor-related (18.1%) and vascular (11.2%) epilepsy. SE was diagnosed in 55.3% of patients. The median time from urgent seizure onset to IV treatment administration was 60.0 min (range: 15.0-360.0), and the median time from IV treatment to IV-BRV was 90.0 min (range: 30.0-2400.0). Regarding dosage, the mean bolus infusion was 163.0 ± 73.0 mg and the mean daily dosage was 195.0 ± 87.0 mg. A total of 77.6% of patients responded to IV-BRV (66.3% with SE vs. 91% other urgent seizures) with a median response time of 30.0 min (range: 10.0-60.0). A sustained response was achieved in 62.8% of patients. However, adverse events were reported in 14.7%, which were predominantly somnolence and fatigue, with 4.5% leading to discontinuation. Eighty-six percent of patients were discharged with oral brivaracetam. CONCLUSION: IV-BRV in emergency settings was effective, and tolerability was good for most patients. However, a larger series is needed to confirm the outcomes.

Alterations in Calcium Handling Are a Common Feature in an Arrhythmogenic Cardiomyopathy Cell Model Triggered by Desmosome Genes Loss.

Arrhythmogenic cardiomyopathy (ACM) is an inherited cardiac disease characterized by fibrofatty replacement of the myocardium. Deleterious variants in desmosomal genes are the main cause of ACM and lead to common and gene-specific molecular alterations, which are not yet fully understood. This article presents the first systematic in vitro study describing gene and protein expression alterations in desmosomes, electrical conduction-related genes, and genes involved in fibrosis and adipogenesis. Moreover, molecular and functional alterations in calcium handling were also characterized. This study was performed d with HL1 cells with homozygous knockouts of three of the most frequently mutated desmosomal genes in ACM: PKP2, DSG2, and DSC2 (generated by CRISPR/Cas9). Moreover, knockout and N-truncated clones of DSP were also included. Our results showed functional alterations in calcium handling, a slower calcium re-uptake was observed in the absence of PKP2, DSG2, and DSC2, and the DSP knockout clone showed a more rapid re-uptake. We propose that the described functional alterations of the calcium handling genes may be explained by mRNA expression levels of ANK2, CASQ2, ATP2A2, RYR2, and PLN. In conclusion, the loss of desmosomal genes provokes alterations in calcium handling, potentially contributing to the development of arrhythmogenic events in ACM.

An uncommon cause of digestive neoplasm: duodenal melanoma.

We present and discuss the case of one patient that presented to the emergency room with abdominal pain in the right hypochondrium radiated to epigastrium and low-grade fever with blood test that shows dissociated colesthasis therefore admitted in the gastroenterology service with choledocholithiasis suspicion. cholangioresonance performed with a sudden stenosis of the bile duct in its intrapancreatic portion due a tumor in the pancreatic head. CT without lessions in other parts of the body. Upper endoscopy shows an ulcerated growth in the papillary area whose biopsies found neoplastic proliferation with S100, SOX10, MelanA and HMB45 positivity.

Link Prediction with Continuous-Time Classical and Quantum Walks.

Protein-protein interaction (PPI) networks consist of the physical and/or functional interactions between the proteins of an organism, and they form the basis for the field of network medicine. Since the biophysical and high-throughput methods used to form PPI networks are expensive, time-consuming, and often contain inaccuracies, the resulting networks are usually incomplete. In order to infer missing interactions in these networks, we propose a novel class of link prediction methods based on continuous-time classical and quantum walks. In the case of quantum walks, we examine the usage of both the network adjacency and Laplacian matrices for specifying the walk dynamics. We define a score function based on the corresponding transition probabilities and perform tests on six real-world PPI datasets. Our results show that continuous-time classical random walks and quantum walks using the network adjacency matrix can successfully predict missing protein-protein interactions, with performance rivalling the state-of-the-art.

Oral and gastric microbiome in relation to gastric intestinal metaplasia.

Evidence suggests that Helicobacter pylori plays a role in gastric cancer (GC) initiation. However, epidemiologic studies on the specific role of other bacteria in the development of GC are lacking. We conducted a case-control study of 89 cases with gastric intestinal metaplasia (IM) and 89 matched controls who underwent upper gastrointestinal endoscopy at three sites affiliated with NYU Langone Health. We performed shotgun metagenomic sequencing using oral wash samples from 89 case-control pairs and antral mucosal brushing samples from 55 case-control pairs. We examined the associations of relative abundances of bacterial taxa and functional pathways with IM using conditional logistic regression with and without elastic-net penalty. Compared with controls, oral species Peptostreptococcus stomatis, Johnsonella ignava, Neisseria elongata and Neisseria flavescens were enriched in cases (odds ratios [ORs] = 1.29-1.50, P = .004-.01) while Lactobacillus gasseri, Streptococcus mutans, S parasanguinis and S sanguinis were under-represented (ORs = 0.66-0.76, P = .006-.042) in cases. Species J ignava and Filifactor alocis in the gastric microbiota were enriched (ORs = 3.27 and 1.43, P = .005 and .035, respectively), while S mutans, S parasanguinis and S sanguinis were under-represented (ORs = 0.61-0.75, P = .024-.046), in cases compared with controls. The lipopolysaccharide and ubiquinol biosynthesis pathways were more abundant in IM, while the sugar degradation pathways were under-represented in IM. The findings suggest potential roles of certain oral and gastric microbiota, which are correlated with regulation of pathways associated with inflammation, in the development of gastric precancerous lesions.

Values and preferences of the general population in Indonesia in relation to rapid COVID-19 antigen self-tests: A cross-sectional survey.

OBJECTIVES: Home diagnostics are essential to assist members of the general population become active agents of case detection. In Indonesia, a country with an over-burdened healthcare system, individuals could use rapid SARS-CoV-2 antigen tests to self-detect COVID-19. To assess the general population's values and attitudes towards SARS-CoV-2 self-testing, a survey was conducted in mid-2021 in Jakarta and the provinces of Banten and North Sulawesi. METHODS: This was a quantitative survey that approached respondents in >600 randomly selected street-points in the three study geographies in July-August 2021. A 35-item questionnaire was used to collect data on key variables, such as likelihood to use a SARS-CoV-2 self-test, willingness to pay for a self-test device, and likely actions following a positive self-test result. Bivariate and multivariate regression analyses were performed. RESULTS: Of 630 respondents (318 were female), 15.53% knew about COVID-19 self-testing, while 62.70% agreed with the idea of people being able to self-test at home, unassisted, for COVID-19. If self-tests were available in Indonesia, >60% of respondents would use them if they felt it necessary and would undertake regular self-testing for example weekly if recommended. Upon receiving a positive self-test result, most respondents would communicate it (86.03%), request post-test counselling (80.79%), self-isolate (97.46%), and/or warn their close contacts (90.48%). CONCLUSIONS: The use of rapid SARS-CoV-2 antigen detection tests for self-testing appears acceptable to a majority of the Indonesian public, to learn whether they have COVID-19. Self-testing should be prioritised to complement to an over-burdened healthcare system by helping the public, asymptomatic individuals included, become agents of change in epidemiological surveillance of SARS-CoV-2 in their communities.

Self-testing for SARS-CoV-2 in São Paulo, Brazil: results of a population-based values and attitudes survey.

BACKGROUND: Brazil is among the countries in South America where the COVID-19 pandemic has hit the general population hardest. Self-testing for SARS-CoV-2 infection is one of the community-based strategies that could help asymptomatic individuals at-risk of COVID-19, as well as those living in areas that are difficult for health personnel to reach, to know their infectious status and contribute to impeding further transmission of the virus. METHODS: A population-based survey was conducted in November 2021, to assess the acceptability of rapid SARS-CoV-2 antigen self-testing among the population of São Paulo. Survey respondents were approached at more than 400 different street-points that were randomly selected using a five-stage randomization process. A 35-item structured questionnaire was used. Dependent variables for our analyses were the likelihood to use and willingness to pay for self-testing, and the likelihood of taking preventive measures to prevent onward transmission of SARS-CoV-2 following a reactive self-test result. Bivariate and multivariate regression analyses were performed. RESULTS: Overall, 417 respondents (44.12% female) participated; 19.66% had previously had COVID-19 disease. A minority (9.59%) felt at high-risk of COVID-19. The majority of both females and males (73.91% and 60.09%, respectively) were in favor of the idea of SARS-CoV-2 self-testing. Overall, if self-tests were available, almost half of the sample would be very likely (n = 54, 12.95%) or likely (n = 151, 36.21%) to use one if they felt they needed to. Upon receiving a positive self-test result, the majority of respondents would communicate it (88.49%), request facility-based post-test counseling (98.32%), self-isolate (97.60%), and warn their close contacts (96.64%). CONCLUSION: Rapid SARS-CoV-2 antigen self-testing could be an acceptable screening tool in São Paulo. The population would be empowered by having access to a technology that would allow them to test, even if asymptomatic, when traveling, or going to work or school. If there is a surge in the incidence of cases, self-testing could be a good approach for mass case detection by Brazil's already overstretched Unified Health System.

Emergent entanglement structures and self-similarity in quantum spin chains.

We introduce an experimentally accessible network representation for many-body quantum states based on entanglement between all pairs of its constituents. We illustrate the power of this representation by applying it to a paradigmatic spin chain model, the XX model, and showing that it brings to light new phenomena. The analysis of these entanglement networks reveals that the gradual establishment of quasi-long range order is accompanied by a symmetry regarding single-spin concurrence distributions, as well as by instabilities in the network topology. Moreover, we identify the existence of emergent entanglement structures, spatially localized communities enforced by the global symmetry of the system that can be revealed by model-agnostic community detection algorithms. The network representation further unveils the existence of structural classes and a cyclic self-similarity in the state, which we conjecture to be intimately linked to the community structure. Our results demonstrate that the use of tools and concepts from complex network theory enables the discovery, understanding and description of new physical phenomena even in models studied for decades. This article is part of the theme issue 'Emergent phenomena in complex physical and socio-technical systems: from cells to societies'.

Assessing Spaniard men's willingness and determinants to use a male contraceptive pill.

OBJECTIVE: As the clinical trials to develop male contraceptive pills are underway, understanding men's attitudes towards this contraceptive method is transcendental. This research was conducted to identify the degree of willingness and the determinants to use male contraceptive pill among Spaniard men. METHODS: A sample of 402 Spaniards men was presented with 36 scenarios comprising four within-subject factors (cost of pills, pill efficacy, side effects and context). In each scenario, a man is asked by his partner to use the contraceptive pill. Participants indicated their own willingness to use the pill in each circumstance. RESULTS: Cluster analysis revealed that participants took one of seven different positions regarding their willingness to use a contraceptive pill: never agree (10%); mainly depends on pill efficacy (6%); mainly depends on side effects (10%); depends on side effects and efficacy (12%); depends on context and side effects (12%); quite always (25%); always agree (25%). Participants' willingness to use contraceptive pills was more pronounced in the case of mild side effects and higher pill efficacy. CONCLUSION: Fifty percent of participants would use the male pill regardless of the circumstances. Access to this contraceptive method, when available, can contribute to greater equity in reproductive rights of the population.

Values and preferences for hepatitis C self-testing among people who inject drugs in Kyrgyzstan.

BACKGROUND: The prevalence of hepatitis C virus (HCV) among people who inject drugs (PWID) continues to be a major public-health burden in this highly stigmatised population. To halt transmission of HCV, rapid HCV self-testing kits represent an innovative approach that could enable PWID to know their HCV status and seek treatment. As no HCV test has yet been licenced for self-administration, it is crucial to obtain knowledge around the factors that may deter or foster delivery of HCV self-testing among PWID in resource-constrained countries. METHODS: A qualitative study to assess values and preferences relating to HCV self-testing was conducted in mid-2020 among PWID in the Bishkek and Chui regions of Kyrgyzstan. Forty-seven PWID participated in 15 individual interviews, two group interviews (n = 12) and one participatory action-research session (n = 20). Responses were analysed using a thematic analysis approach with 4 predefined themes: awareness of HCV and current HCV testing experiences, and acceptability and service delivery preferences for HCV self-testing. Informants' insights were analysed using a thematic analysis approach. This research received local ethics approval. RESULTS: Awareness of HCV is low and currently PWID prefer community-based HCV testing due to stigma encountered in other healthcare settings. HCV self-testing would be accepted and appreciated by PWID. Acceptability may increase if HCV self-testing: was delivered in pharmacies or by harm reduction associations; was free of charge; was oral rather than blood-based; included instructions with images and clear information on the test's accuracy; and was distributed alongside pre- and post-testing counselling with linkage to confirmatory testing support. CONCLUSIONS: HCV self-testing could increase awareness of and more frequent testing for HCV infection among PWID in Kyrgyzstan. It is recommended that peer-driven associations are involved in the delivery of any HCV self-testing. Furthermore, efforts should be maximised to end discrimination against PWID at the healthcare institutions responsible for confirmatory HCV testing and treatment provision.

Values and preferences for hepatitis C self-testing among the general population and healthcare workers in Rwanda.

BACKGROUND: In 2018, Rwanda launched a 5-year hepatitis C virus (HCV) elimination plan as per the World Health Organization global targets to eliminate HCV by 2030. To improve awareness of HCV status, strategies are needed to ensure easy access to HCV testing by as-yet unreached populations. HCV-self-testing, an innovative strategy, could further increase HCV testing uptake. This assessment explores perceptions around HCV self-testing among members of the public and healthcare workers in Rwanda. METHODS: A qualitative study was undertaken in Masaka District Hospital, comprising individual interviews, group interviews and participatory action research (PAR) activities. Purposive and snowball sampling methods guided the selection of informants. Informed consent was obtained from all participants. A thematic analysis approach was used to analyse the findings. RESULTS: The participants comprised 36 members of the public and 36 healthcare workers. Informants appreciated HCV self-testing as an innovative means of increasing access to HCV testing, as well as an opportunity to test privately and subsequently autonomously decide whether to seek further HCV care. Informants further highlighted the need to make HCV self-testing services free of charge at the nearest health facility. Disadvantages identified included the lack of pre/post-test counselling, as well as the potential psychosocial harm which may result from the use of HCV self-testing. CONCLUSION: HCV self-testing is perceived to be an acceptable method to increase HCV testing in Rwanda. Further research is needed to assess the impact of HCV self-testing on HCV cascade of care outcomes.

Epigenetic Changes Governing Scn5a Expression in Denervated Skeletal Muscle.

The SCN5A gene encodes the α-subunit of the voltage-gated cardiac sodium channel (NaV1.5), a key player in cardiac action potential depolarization. Genetic variants in protein-coding regions of the human SCN5A have been largely associated with inherited cardiac arrhythmias. Increasing evidence also suggests that aberrant expression of the SCN5A gene could increase susceptibility to arrhythmogenic diseases, but the mechanisms governing SCN5A expression are not yet well understood. To gain insights into the molecular basis of SCN5A gene regulation, we used rat gastrocnemius muscle four days following denervation, a process well known to stimulate Scn5a expression. Our results show that denervation of rat skeletal muscle induces the expression of the adult cardiac Scn5a isoform. RNA-seq experiments reveal that denervation leads to significant changes in the transcriptome, with Scn5a amongst the fifty top upregulated genes. Consistent with this increase in expression, ChIP-qPCR assays show enrichment of H3K27ac and H3K4me3 and binding of the transcription factor Gata4 near the Scn5a promoter region. Also, Gata4 mRNA levels are significantly induced upon denervation. Genome-wide analysis of H3K27ac by ChIP-seq suggest that a super enhancer recently described to regulate Scn5a in cardiac tissue is activated in response to denervation. Altogether, our experiments reveal that similar mechanisms regulate the expression of Scn5a in denervated muscle and cardiac tissue, suggesting a conserved pathway for SCN5A expression among striated muscles.

MiR130b from Schlafen4+ MDSCs stimulates epithelial proliferation and correlates with preneoplastic changes prior to gastric cancer.

The myeloid differentiation factor Schlafen4 (Slfn4) marks a subset of myeloid-derived suppressor cells (MDSCs) in the stomach during Helicobacter-induced spasmolytic polypeptide-expressing metaplasia (SPEM). OBJECTIVE: To identify the gene products expressed by Slfn4+-MDSCs and to determine how they promote SPEM. DESIGN: We performed transcriptome analyses for both coding genes (mRNA by RNA-Seq) and non-coding genes (microRNAs using NanoString nCounter) using flow-sorted SLFN4+ and SLFN4- cells from Helicobacter-infected mice exhibiting metaplasia at 6 months postinfection. Thioglycollate-elicited myeloid cells from the peritoneum were cultured and treated with IFNα to induce the T cell suppressor phenotype, expression of MIR130b and SLFN4. MIR130b expression in human gastric tissue including gastric cancer and patient sera was determined by qPCR and in situ hybridisation. Knockdown of MiR130b in vivo in Helicobacter-infected mice was performed using Invivofectamine. Organoids from primary gastric cancers were used to generate xenografts. ChIP assay and Western blots were performed to demonstrate NFκb p65 activation by MIR130b. RESULTS: MicroRNA analysis identified an increase in MiR130b in gastric SLFN4+ cells. Moreover, MIR130b colocalised with SLFN12L, a human homologue of SLFN4, in gastric cancers. MiR130b was required for the T-cell suppressor phenotype exhibited by the SLFN4+ cells and promoted Helicobacter-induced metaplasia. Treating gastric organoids with the MIR130b mimic induced epithelial cell proliferation and promoted xenograft tumour growth. CONCLUSION: Taken together, MiR130b plays an essential role in MDSC function and supports metaplastic transformation.