Baobab Index

Piezo2 channels are mechanosensors expressed in dorsal root ganglia and Merkel cells, and involved in proprioception and touch sensation. PIEZO2 pathogenic variants cause rare autosomal dominant and recessive disorders. Dominant forms include distal arthrogryposis type 3, 5, and Marden-Walker syndrome, whereas the recessive form corresponds to distal arthrogryposis with impaired proprioception and touch (DAIPT). Given the rarity of these conditions, additional reports are essential to refine their phenotypic characterization. We conducted a multicenter, retrospective study to identify patients with genetically confirmed PIEZO2-related disorders. We collected clinical data through a standardized assessment. Previously published cases were included when more detailed phenotypic information was available. We identified 44 individuals with a clinical diagnosis of PIEZO2-related disorders. Among them, we selected 42 patients with a confirmed molecular diagnosis. Sixteen of them (10 males and 6 females; median age at diagnosis: 8 years; range 0.9-14) carried biallelic pathogenic PIEZO2 variants. They typically presented with neonatal hypotonia and respiratory distress with feeding difficulties. Distal arthrogryposis was associated with a variable multisystemic involvement, including the musculoskeletal system with scoliosis, hip dislocation and laryngomalacia. Twenty-five patients (11 males and 14 females; median age at diagnosis: 7 years; range 0.3-39 years) carried monoallelic variants, exhibiting a broad phenotypic spectrum. An additional prenatal diagnosis (at 23 weeks of gestation) was reported among heterozygous cases. In our cohort, ten previously unpublished causative variants were identified. A systematic assessment of skeletal muscle involvement revealed a severe myofibrillar disarray in one case. This study provides a comprehensive and systematic phenotypic characterization of patients across the spectrum of PIEZO2-related disorders. Our findings support a clear clinical distinction between recessive and dominant forms. The clinical manifestations extend beyond the peripheral nervous system and the Merkel cells, suggesting a broader PIEZO2 tissue expression during early developmental stages. Dominant PIEZO2-related disorders are heterogeneous, ranging from mild to severe forms. Our study also suggests that many patients exhibit a respiratory involvement, emphasizing the need for regular respiratory follow-up in the long-term clinical management of both dominant and recessive forms.

Strigolactones are ecologically, developmentally, and physiologically important hormones, but much remains unknown about their evolution and role in non-model species. Sorghum is a globally important C4 cereal and exhibits natural variation in root-exuded strigolactones. Differences in sorghum strigolactone stereochemistry are associated with resistance to parasitic plants, but with evidence for potential trade-offs. We studied sorghum mutants of loci in the strigolactone biosynthetic pathway, CAROTENOID CLEAVAGE DIOXYGENASE 8 (SbCCD8b) and LOW GERMINATION STIMULANT 1 (LGS1), both previously shown to be Striga resistant by stimulating little germination of the parasite. SbCCD8b CRISPR-Cas9 deletions changed the accumulation of low abundance metabolites, reduced net carbon assimilation rate, altered root architecture and anatomy, and diminished the establishment and benefit of mycorrhizal symbionts. For Striga-resistant LGS1 CRISPR-Cas9 deletions, differentially expressed genes were enriched with promoter motifs that regulate stress response and growth pathways, net carbon assimilation rate was reduced, and the colonization of mycorrhizal symbionts was delayed. We additionally restored functional LGS1 into the RTx430 genetic background, which normally has the lgs1-2 natural deletion allele. While root exudates from LGS1 insertion mutants rescued Striga susceptibility, we did not see consistent rescue of other traits altered in LGS1 loss-of-function mutants. We hypothesize that epistasis with a neighboring strigolactone synthesis gene, which is rarely lost without concomitant loss of LGS1, may alter the phenotypic effects of LGS1 variation. Our study gives context to potential trade-offs associated with host resistance to parasitic plants and, more broadly, builds on the contribution of strigolactones in shaping sorghum physiological processes, growth, and development.

Arboviral surveillance in Africa is limited by fragmented diagnostic capacity and insufficient integration of molecular detection with genomic epidemiology, particularly in settings where dengue (DENV), Zika (ZIKV), and chikungunya (CHIKV) viruses co-circulate and present with overlapping clinical syndromes. We conducted a molecular surveillance study across multiple regions in Senegal, including samples collected from 367 individuals with febrile or nonfebrile illness. A tiered workflow was implemented using multiplex reverse transcription quantitative polymerase chain reaction (RT-qPCR) screening for DENV, ZIKV, and CHIKV, performed on a combination of individually tested samples (n = 43) and pooled samples (three individuals per pool). DENV RT-qPCR-positive samples were further characterized by RT recombinase polymerase amplification (RT-RPA) serotyping and genomic sequencing. Multiplex RT-qPCR revealed concurrent circulation of multiple arboviruses. Among individually tested samples, positivity rates were 20.9% (9/43) for DENV, 9.3% (4/43) for ZIKV, and 11.6% (5/43) for CHIKV. In pooled screening across all sites (108 pools), positivity rates were 18.5% for DENV (20/108), 5.6% for ZIKV (6/108), and 10.2% for CHIKV (11/108), indicating widespread arboviral transmission. DENV-1-4 serotyping by RT-RPA demonstrated complete concordance with RT-qPCR and identified exclusive circulation of DENV-2, enabling triage of samples for downstream genomic sequencing. Amplicon-based sequencing substantially improved genome recovery compared with metagenomic sequencing, yielding near-complete genomes in 77.8% (14/18) of RT-RPA-positive samples. Phylogenetic analyzes demonstrated that all sequences clustered within the DENV-2 cosmopolitan genotype (genotype II), lineage II-F.1.1, closely related to recent strains from West Africa and Asia. Time-resolved reconstruction suggested recent emergence (∼2022-2023) and rapid expansion, consistent with ongoing transmission and regional dissemination. These findings demonstrate co-circulation of DENV, ZIKV, and CHIKV in Senegal and provide evidence of recent expansion of DENV-2 within a globally connected transmission network. A tiered strategy integrating pooled molecular screening with RT-RPA triage and genomic sequencing offers a scalable framework for arboviral surveillance in resource-limited settings.

Norovirus is a leading cause of acute gastroenteritis worldwide due to its high contagiousness, widespread transmission, and the lack of treatment or vaccine. In Senegal, no routine community-level monitoring is performed, and most available data concern other enteric viruses, leaving a gap in understanding norovirus circulation. To assess the potential of wastewater surveillance as an early warning system, we analyzed the spatiotemporal circulation in Senegal of noroviruses using clinical and environmental data collected between 2020 and 2023, combining statistical and machine learning models, and comparing effective reproduction number R(t) estimates between genotypes and surveillance systems. Our data show that norovirus GII was the dominant genotype during the study period. In addition, a strong spatial heterogeneity in viral load was identified between wastewater collection sites, with high titers observed in several wastewater collection sites. Interestingly, peaks of viral load in environmental setting frequently preceded increases in reported clinical cases. Modeling data indicated more persistent circulation of norovirus GII than GI. Our findings also highlighted the influence of temporal, demographic, and clinical factors for viral loads in wastewater. Comparison of the effective reproduction number R(t) confirmed the descriptive data and highlighted a more persistent circulation for norovirus GII and a detection of R(t)'s increases in wastewater data prior to variation in clinical data, underscoring the usefulness of wastewater environmental surveillance as an early warning tool system for norovirus surveillance. Our study is noteworthy by representing the first countrywide application of wastewater-based epidemiology to monitor norovirus circulation across diverse geographic and demographic settings in Senegal. Noroviruses represent a major public health concern worldwide, particularly in low- and middle-income countries, such as Senegal where resources are limited. Monitoring noroviruses in wastewater is critical for early detection of outbreaks and tracking viral evolution, as these viruses are often underdiagnosed in clinical settings. In this study, we report on the spatiotemporal circulation of noroviruses in Senegal using clinical and environmental data collected over 4 years and combining modeling methods with estimation of epidemiological parameters. Our study provides the first countrywide data on the application of wastewater-based epidemiology to monitor noroviruses across diverse geographic and demographic settings in Senegal. Our data offer a proactive, cost-effective method to monitor public health trends and identify the presence of noroviruses within the population, offering an early warning system for community spread. The approach could be useful for the monitoring of other public health concerns in Senegal in the absence of routine clinical surveillance.

The first confirmation of chikungunya virus infection in Guinea is reported in the present study. The patient, a 68-year-old woman presumptively diagnosed with malaria and with no history of travel, was identified through a research project focused on the etiologies of febrile illnesses in Guinea. A whole-blood sample from the patient was analyzed using multiplex reverse-transcription polymerase chain reaction, yielding a positive result for chikungunya virus, and was subsequently sequenced. The near-complete genome sequence was most closely related to strains circulating that year in Senegal. The study data are noteworthy because, despite past serological evidence of transmission, active human infection with the chikungunya virus has not previously been observed in Guinea; its emergence is linked to the identification of Aedes vectors in Dalaba. Further clinical and entomological investigations are warranted, along with country-wide genomic surveillance of arboviruses to better understand risk factors that have driven the emergence of chikungunya in Guinea and prevent possible future epidemics.

Since the beginning of the COVID-19 pandemic, a large number of SARS-CoV-2 variants have emerged from the reference strain (Wuhan-Hu-1, NC_045512.2). Using these variants to understand the genetic diversity and temporal dynamics of SARS-CoV-2 in Niger is essential for developing and implementing effective public health interventions. SARS-CoV-2 detection was performed on nasopharyngeal samples collected from travelers and symptomatic patients at the National Reference Laboratory in Niger from March 2020 to March 2023 using RT-qPCR techniques. A subset of samples with a cycle threshold <28 were selected for whole-genome sequencing and genomic analysis, which included phylogenetic reconstruction to study the evolutionary relationships of SARS-CoV-2 variants detected in Niger. Among 286,872 samples from suspected cases tested, we confirmed 8266 positives for SARS-CoV-2, resulting in a positivity rate of 2.88%. Of the positive cases, 268 (3.24%) resulted in death and 5577 (67.48%) were travelers. All the WHO-designated Variants of Concern (VOCs), including Alpha B.1.1.7 (n = 2), Beta B.1.351 (n = 1), Delta B.1.617 (n = 20) and Omicron B.1.1.529 (n = 95) circulated in Niger during the study period. Among the Variants of Interest (VOIs) and Variants Under Monitoring (VUMs), the A27 lineage (n = 49) was the predominant virus detected and co-circulated with Eta lineage B.1.525 (n = 21). Phylogeographic analysis identified at least 60 independent introductions of SARS-CoV-2 into Niger, the majority of which were closely related to published sequences from other African countries (n = 25) and European countries (n = 24). Phylogenetic analysis of the four predominant variants revealed a temporal progression of SARS-CoV-2 lineages in Niger, with well-supported clades. A high number of mutations were observed, mainly located in the spike protein, ORF1a, and ORF1b genes. This study helps to understand the SARS-CoV-2 evolution and dynamics in Niger Republic, where diagnostic capacities and containment measures were challenging.

Evolving genomic diversity of Mycobacterium tuberculosis complex pathogens is poorly known in French Polynesia, a remote archipelago in the southern Pacific Ocean. A total of 321 mycobacteria sampled from 321 patients presenting pulmonary tuberculosis between 1998 and 2010 at the microbiology laboratory of the French Polynesia Hospital Centre in Tahiti were whole genome sequenced (WGS), disclosing three major M. tuberculosis sensu stricto sublineages: L4.4.1.1 S-type, L4.1.1.3 X-Type, and L4.1.2.1 Haarlem. Furthermore, 20 isolates were identified as nontuberculous mycobacteria, including Mycobacterium fortuitum, which accounted for 65% of the identified nontuberculous mycobacteria, as well as Mycobacterium paragordonae and Mycobacterium gordonae identified with M. tuberculosis in two samples. Two further isolates were potentially representative of novel species in the Mycobacterium and Actinomadura genera. In total, 43 isolates exhibited in silico predicted antibiotic resistance to first- and second-line antibiotics. Combined with previously published data, the data reported here indicate a 12-year trend of decreasing diversity among the M. tuberculosis population circulating in Tahiti and the seemingly unsuccessful implantation of a recently imported of East African-Indian sublineage (L1.2.1.2.1). These findings contrast with the long-term persistence and predominance of the X-type family with L4.1.1.3; the S-type family with L4.4.1.1 and L4.4.2; the Haarlem family with L4.1.2 and L4.1.2.1, and the LAM family with L4.3.3, L4.3.2, and L4.3.4.2. These observations suggest that in remote territories such as the French Polynesia archipelago M. tuberculosis may rapidly adapt to local ecosystems.

The application of next-generation sequencing (NGS) is rapidly expanding for antimicrobial resistance (AMR) surveillance and clinical decision-making. However, despite a high AMR burden, many low- and middle-income countries lack the infrastructure and technical capacity required to implement sequencing-based approaches. To address this gap and demonstrate the practical application of the technology, we compared the performance of nanopore sequencing combined with real-time analysis using the EPI2ME platform in a mobile laboratory with that of a hybrid sequencing approach integrating Illumina short reads and nanopore long reads. In this exploratory diagnostic evaluation study, 25 A total of 36 These findings support the feasibility of deploying nanopore sequencing in mobile suitcase laboratories to strengthen AMR surveillance in food production systems. Given its portability, rapid turnaround time, and minimal infrastructure requirements, the approach may also have broader applications for One Health based AMR surveillance, clinical decision-making, and outbreak investigations in resource-limited settings.

Radiotherapy r5emains a cornerstone of treatment for localized and locally advanced prostate cancer, yet substantial heterogeneity persists in oncological outcomes and treatment-related toxicity. Increasing evidence suggests that systemic inflammation, immune microenvironment characteristics, and tumor-specific molecular features contribute to these variations and may provide clinically relevant biomarkers. This narrative review summarizes current evidence regarding immunological and inflammatory biomarkers in prostate cancer treated with radiotherapy, focusing on their biological rationale, prognostic significance, predictive potential, and clinical applicability. Circulating biomarkers, including neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, C-reactive protein, fibrinogen, and cytokines such as IL-6 and TGF-β1, have been associated with oncological outcomes and toxicity in several studies. However, their interpretation remains limited by biological nonspecificity, methodological heterogeneity, variable cutoff definitions, and lack of prospective validation. Within the tumor microenvironment, immune cell populations, including CD8

Commensal mammals offer unique opportunities to study how human-mediated dispersal, admixture, and secondary contact shape genomic variation during range expansion, yet for one of the most successful invasive commensals globally, the western house mouse Mus musculus domesticus, invasion dynamics across Africa remain largely unexplored. Here, we present a large-scale population genomic analysis of 380 whole-genome sequences, including 303 newly sequenced low-coverage genomes, of which 216 are from 13 distinct African populations, enabling us to investigate how human-mediated dispersal and secondary contact with native species shape the genomic legacy of a commensal mammal invasion. Ancestry analyses reveal contributions from at least three major Eurasian source lineages contributing to African populations: an Iberian-West Asian lineage present in Morocco, Algeria, and Niger; a Mediterranean lineage represented in Tunisia; and a Northern European lineage dominant in West and Central Africa. Demographic inferences indicate both recent and ancient episodes of divergence and population contraction. In West and Central Africa, divergence times broadly overlap with European maritime expansion and colonial trade. In contrast, North African populations exhibit older coalescent signals, consistent with early participation in the western Mediterranean radiation. We also detect substantial introgression from the native Mus spretus into North African populations in regions of sympatry. Collectively, our results reveal that the African invasion of the house mouse was not a single demographic process but a mosaic of population-specific histories shaped by multiple introductions, shifting connectivity through time, admixture, and interspecific gene flow. These findings reinforce the importance of population-level perspectives in invasion genomics, especially for commensal mammals whose dispersal is closely tied to human movement, and establish the most extensive open genomic resource for wild African house mice.