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Monkeypox virus clade I is endemic in several central African countries and characterised by an increase in disease severity and mortality. Since October, 2023, a large-scale mpox outbreak has emerged in DR Congo, and in March, 2024, the first individuals with mpox were reported outside the endemic areas in Republic of the Congo. We aimed to provide insight into the epidemic by sequencing samples obtained from individuals with mpox in Republic of the Congo.

Très peu de travaux abordent la tuberculose (TB) pré- et ultrarésistante.

Due to its multiple features, including the ability to orchestrate remote communication between different tissues, the exosomes are the extracellular vesicles arousing the highest interest in the scientific community. Their size, established as an average of 30–150 nm, allows them to be easily uptaken by most cells. According to the type of cells-derived exosomes, they may carry specific biomolecular cargoes used to reprogram the cells they are interacting with. In certain circumstances, exosomes stimulate the immune response by facilitating or amplifying the release of foreign antigens-killing cells, inflammatory factors, or antibodies (immune activation). Meanwhile, in other cases, they are efficiently used by malignant elements such as cancer cells to mislead the immune recognition mechanism, carrying and transferring their cancerous cargoes to distant healthy cells, thus contributing to antigenic invasion (immune suppression). Exosome dichotomic patterns upon immune system regulation present broad advantages in immunotherapy. Its perfect comprehension, from its early biogenesis to its specific interaction with recipient cells, will promote a significant enhancement of immunotherapy employing molecular biology, nanomedicine, and nanotechnology.

Roadway transient electromagnetic method has been widely used in detecting mine water disaster ahead of roadway excavation face. Due to the strong mutual inductance between transmitting-receiving coils, the early-stage data obtained by this method are seriously distorted and the effective resolving time of transient electromagnetic (TEM) field is greatly lengthened, which leads to the shallow blind area of exploration. To improve the ability of transient electromagnetic testing system and to resolve short-range geoelectric abnormalities in front of the roadway excavation face, we provided the expression functions of the primary TEM field and the receiving system’s impulse response, restored the data recorded by instrument theoretically and compared the differences between the recorded data and the pure secondary TEM data. We found that the factors, including the increase in the current switch-off time, the decline in the receiving coils’ inherent resonant frequency, the enlargement in the mutual inductance between transmitting-receiving coils, and the mismatch in the receiving circuit’s damping resistance and so on, could significantly affect the early-stage TEM data, which results in a great delay in the effective resolving time. Based on the above findings, we improved the TEM testing system, compared the monitored data obtained using the original and improved testing system. It demonstrates that the improved testing system shortened the effective resolving time, which greatly enhanced the reliability of early-stage data and efficiently resolved the geoelectric abnormal zones closer to the roadway excavation face.

An effective control of malaria vectors requires an extensive knowledge of mechanisms underlying the resistance-phenotypes developed by these vectors against insecticides. We investigated Anopheles gambiaemosquitoes from Benin and Togo for their intensity of insecticide resistance and we discussed the involvement of genotyped mechanisms in the resistance-phenotypes observed. Three- to five-day-old adult mosquitoes emerged from field and laboratory An. gambiaelarvae were assayed using WHO tube intensity tests against various doses of deltamethrin: 1× (0.05%); 2× (0.1%); 5× (0.25%); 7.5× (0.375%) and those of pirimiphos-methyl: 0.5× (0.125%); 1× (0.25%). Members of An. gambiaecomplex were screened in field populations using polymerase chain reaction (PCR) assays. The presence of kdrR(1014F/1014S) and ace-1R(119S) mutations was also investigated using TaqMan and PCR-RFLP techniques, respectively. Anopheles gambiaefrom field were very resistant to deltamethrin, whereas KisKdr and AcerKdrKis strains displayed 100% mortality rates at 2× the diagnostic dose. In contrast, the field mosquitoes displayed a low resistance-intensity against 1× the diagnostic dose of pirimiphos-methyl, whereas AcerKis and AcerKdrKis strains showed susceptibility at 0.5× the diagnostic dose. Anopheles gambiae s.s., Anopheles coluzzii, and Anopheles arabiensiswere identified. Allelic frequencies of kdrR(1014F) and ace-1R(119S) mutations in the field populations varied from 0.65 to 1 and 0 to 0.84, respectively. The field An. gambiaedisplayed high-resistance levels against deltamethrin and pirimiphos-methyl when compared with those of the laboratory An. gambiae-resistant strains. These results exhibit the complexity of underlying insecticide resistance mechanisms in these field malaria vectors.Graphical AbstractThe field An. gambiaedisplayed high resistance levels against deltamethrin and pirimiphos-methyl when compared to those of the laboratory An. gambiaeresistant strains. These results exhibit the complexity of underlying insecticide resistance mechanisms in these field malaria vectors. Figure. (a) Deltamethrin and (b) pirimiphos-methyl exposures.

AbstractThe fungal pathogen Batrachochytrium dendrobatidis(Bd) is implicated in global declines of amphibian populations and has been documented in African specimens originally collected as far back as the 1930s. Numerous recent surveys focusing on regional pathogen prevalence have greatly increased the number of known occurrences of Bdin African species, but few studies have focused on continental distribution patterns. We analyzed all known positive occurrences of Bdin African amphibians to date, including newly reported data from Cameroon, the Democratic Republic of the Congo, Gabon, Namibia, and the Republic of the Congo. Records from both Namibia and the Republic of the Congo reported herein represent first positive occurrences for these countries. With this most comprehensive sampling of the African continent to date we identified patterns of Bd-positive occurrences associated with (1) location (i.e., biogeographic region, country), (2) taxonomy, (3) life history, and (4) threat of extinction. We used fine-grained (30 arc seconds) environmental niche models (ENMs) to predict the continental distribution of Bdand identify hotspots for the pathogen, including areas not previously modeled to have high suitability for the fungus, and areas of high amphibian biodiversity from which Bdhas not yet been documented. Our ENMs predicted that the environmentally suitable range of Bdencompasses vast areas of high amphibian biodiversity, including the Congo Basin and the Albertine Rift. Although our ENMs indicated that West Africa is environmentally suitable for Bd, the fungus has not been reported west of the Dahomey Gap. Likewise, the ENMs also identified regions across the Congo Basin and coastal Angola that are environmentally suitable for the pathogen but from which Bdhas not yet been reported, underscoring a need for Bdsurveys in these regions. Although amphibian declines in Africa have not been directly attributed to chytridiomycosis, Bdhas been detected in over one fifth of the most-threatened African amphibians. Given the presence of the hypervirulent Bdglobal panzootic lineage (BdGPL) in Africa, we believe that the threat of Bdas a novel pathogen may be underestimated and that focused research is urgently needed to identify which species are susceptible to Bd-driven declines.

In this article, an account is given of the planning and production of a corpus of Yilumbu. The primary focus of the article is on the presentation of the project background. Then the article also gives an account of the dictionary conceptualisation plan, i.e. the general preparation phase, the material acquisition phase, the material preparation phase, the material processing phase and the publishing preparation phase. The present research will only give an account of the dictionary conceptualisation plan as well as future work.

AbstractThe fungal pathogen Batrachochytrium dendrobatidis(Bd) is implicated in global declines of amphibian populations and has been documented in African specimens originally collected as far back as the 1930s. Numerous recent surveys focusing on regional pathogen prevalence have greatly increased the number of known occurrences of Bdin African species, but few studies have focused on continental distribution patterns. We analyzed all known positive occurrences of Bdin African amphibians to date, including newly reported data from Cameroon, the Democratic Republic of the Congo, Gabon, Namibia, and the Republic of the Congo. Records from both Namibia and the Republic of the Congo reported herein represent first positive occurrences for these countries. With this most comprehensive sampling of the African continent to date we identified patterns of Bd-positive occurrences associated with (1) location (i.e., biogeographic region, country), (2) taxonomy, (3) life history, and (4) threat of extinction. We used fine-grained (30 arc seconds) environmental niche models (ENMs) to predict the continental distribution of Bdand identify hotspots for the pathogen, including areas not previously modeled to have high suitability for the fungus, and areas of high amphibian biodiversity from which Bdhas not yet been documented. Our ENMs predicted that the environmentally suitable range of Bdencompasses vast areas of high amphibian biodiversity, including the Congo Basin and the Albertine Rift. Although our ENMs indicated that West Africa is environmentally suitable for Bd, the fungus has not been reported west of the Dahomey Gap. Likewise, the ENMs also identified regions across the Congo Basin and coastal Angola that are environmentally suitable for the pathogen but from which Bdhas not yet been reported, underscoring a need for Bdsurveys in these regions. Although amphibian declines in Africa have not been directly attributed to chytridiomycosis, Bdhas been detected in over one fifth of the most-threatened African amphibians. Given the presence of the hypervirulent Bdglobal panzootic lineage (BdGPL) in Africa, we believe that the threat of Bdas a novel pathogen may be underestimated and that focused research is urgently needed to identify which species are susceptible to Bd-driven declines.

Duchenne muscular dystrophy (DMD) is a lethal muscle-wasting disease currently without cure. We investigated the use of the PiggyBac transposon for full-length dystrophin expression in murine mesoangioblast (MABs) progenitor cells. DMD murine MABs were transfected with transposable expression vectors for full-length dystrophin and transplanted intramuscularly or intra-arterially into mdx/SCID mice. Intra-arterial delivery indicated that the MABs could migrate to regenerating muscles to mediate dystrophin expression. Intramuscular transplantation yielded dystrophin expression in 11%–44% of myofibers in murine muscles, which remained stable for the assessed period of 5 months. The satellite cells isolated from transplanted muscles comprised a fraction of MAB-derived cells, indicating that the transfected MABs may colonize the satellite stem cell niche. Transposon integration site mapping by whole-genome sequencing indicated that 70% of the integrations were intergenic, while none was observed in an exon. Muscle resistance assessment by atomic force microscopy indicated that 80% of fibers showed elasticity properties restored to those of wild-type muscles. As measured in vivo, transplanted muscles became more resistant to fatigue. This study thus provides a proof-of-principle that PiggyBac transposon vectors may mediate full-length dystrophin expression as well as functional amelioration of the dystrophic muscles within a potential autologous cell-based therapeutic approach of DMD.

Given an endofunctor F of an arbitrary category, any maximal element of the lattice of congruence relations on an F-coalgebra (A, a) is called a coatomic congruence relation on (A, a). Besides, a coatomic congruence relation K is said to be factor split if the canonical homomor-phism ν : AK → A∇Asplits, where ∇Ais the largest congruence relation on (A, a). Assuming that F is a covarietor which preserves regular monos, we prove under suitable assumptions on the underlying category that, every quotient coalgebra can be made extensional by taking the regular quotient of an F-coalgebra with respect to a coatomic and not factor split congruence relation or its largest congruence relation.

We studied the innate immune system of Cynomolgus monkeys (Macaca fascicularis) experimentally infected via the vaginal mucosae with a virulent simian immunodeficiency virus isolate SIVmac251. Animals were evaluated for their natural killer (NK) cell activity, and for their antibody-dependent cellular cytotoxicity. NK cells from SIVmac251-infected macaques show impaired NK cell activity compared to cells from uninfected animals. Subsequent treatment of NK cells with interferon-α(IFN-α) or interleukin-12 (IL-12) alone partially restored the NK activity. However, either treatment of NK cells with both IFN-αand IL-12 completely reversed the impairment of cytotoxicity induced by simian immunodeficiency virus (SIV) infection. Incubation of NK cells from infected but not from uninfected monkeys with IFN-αand IL-12 for 8 days increased the percentage of CD16+/CD56+cells twofold to fivefold and enhanced antibody-dependent cellular cytotoxicity (ADCC) activity. Thus IFN-αand IL-12 greatly enhance both the NK cell and ADCC activities of peripheral blood cells from SIVmac251-infected animals and increase the number of NK cells in longer term culture. The combined effect of IFN-αand IL-12 in enhancing NK cell activity may provide a novel therapeutic approach for the restoration of depressed NK cell activity observed in human immunodeficiency virus (HIV)-infected patients.