Centre Hospitalier Universitaire de Martinique

MECOM encodes a developmental and haematopoietic transcription factor associated with a rare early-onset syndrome including bone marrow failure, skeletal and other congenital anomalies. Heterozygous de novo variants are the primary cause. We previously identified MECOM as a candidate gene for paediatric pulmonary arterial hypertension (PAH) using trio exome sequencing. To test the role of MECOM in paediatric PAH and further define the clinical phenotype of MECOM-associated syndrome, we queried GeneMatcher and screened rare disease databases for individuals with predicted deleterious MECOM variants. We analysed the clinical spectrum of patients, performed protein modelling of genetic variants and assessed cardiopulmonary expression. We identified 15 individuals with MECOM variants, including 11 unrelated probands and 8 de novo variants. 11 individuals had severe or mild thrombocytopenia, 9 had skeletal issues, 8 had cardiac anomalies, 6 had PAH and 10 had additional conditions. Three were diagnosed in utero and died in the neonatal period. All missense variants map to the zinc finger 6 or zinc finger 8/9 region, a known hotspot for MECOM-associated syndrome. Protein modelling predicted that both regions are DNA-binding, and that the variants may interfere with binding to a VEGFR2/KDR enhancer. Data from LungMAP showed that MECOM is primarily expressed in pulmonary arterial endothelial cells. Rare MECOM variants are associated with early-onset syndromic PAH. PAH monitoring should be considered for all individuals with rare MECOM variants. We speculate that the pathogenetic mechanism for PAH and cardiac defects may be impaired VEGFR2/KDR signalling.

In temporal lobe epilepsy (TLE), locally reduced glucose metabolism (i.e., hypometabolism) is indicative of the epileptogenic onset zone (EZ). Here, we investigate the potential value of resting-state fMRI (rs-fMRI) for localizing the EZ with fluorodeoxyglucose positron emission tomography (FDG-PET) as ground truth. Twelve PET-positive patients (34.1 ± 13.1 y; 5 females) with unilateral drug-resistant TLE were included. FDG-PET and rs-fMRI were acquired simultaneously at a hybrid 3T PET-MR scanner. Hypometabolic regions were identified on the FDG-PET images by a nuclear medicine expert. The FDG-PET images were compared with a clinical FDG-PET control dataset with normal glucose uptake distribution. The output z-score maps were thresholded at z < -2 to produce a binary mask of the significantly hypometabolic regions. The hypometabolism masks were mirrored onto the contralateral hemisphere for the asymmetry comparison. Regional homogeneity (ReHo), amplitude of low-frequency fluctuations (ALFF), and fractional ALFF (fALFF) were calculated from the rs-fMRI in conventional (0.01-0.1 Hz) and slow-3 (0.073-0.198 Hz) frequency bands. Asymmetry indices (AIs) were calculated using the ipsilateral and contralateral hypometabolic masks in the PET-positive subjects and assessed via the one-sample Wilcoxon test and Spearman correlation coefficients. The AIs of conventional fALFF were significantly lower in the hypometabolic zone (p < 0.05). A significant negative correlation was found between the AIs of FDG-PET and fALFF in the slow-3 band (r = -0.62; p < 0.05). Conventional and slow-3 band fALFF showed a potential to mimic the FDG-PET findings in terms of EZ localization. Further research with extended cohorts and histopathological validation is required to determine the clinical value.

L’évolution des critères de classification des spondyloarthrites a permis d’améliorer le repérage des formes précoces, mais leur application reste conditionnée par l’accès à l’imagerie (radiographie/IRM) et au typage HLA-B27. D’autre part, l’hétérogénéité dans la répartition ethnique de l’allèle HLA-B27 suggère que sa sous-représentation serait à l’origine d’une prévalence plus faible de la maladie dans des populations spécifiques. Ainsi, la moindre prévalence des spondyloarthrites dans les populations afrodescendantes est généralement attribuée à la faible prévalence du HLA-B27 dans ces populations. Cette revue met en perspective les données épidémiologiques, cliniques, biologiques et génétiques des spondyloarthrites dans les populations d’Afrique subsaharienne et dans la diaspora africaine noire. En Afrique subsaharienne, on constate une évolution dans le temps avec les cohortes qui ont augmenté en taille et un glissement des séries centrées sur la spondylarthrite ankylosante vers des spondyloarthrites dominées par les arthrites réactionnelles, les spondyloarthrites indifférenciées et parfois les arthrites liées au VIH. Sur le plan génétique, le HLA-B27 est peu fréquent en population générale d’Afrique subsaharienne, son association à la spondyloarthrite y apparaît modeste, et d’autres profils HLA—HLA-B14:03 et HLA-B57:03— sont rapportés. Dans la diaspora africaine noire, la positivité HLA-B27 reste plus faible chez les afrodescendants que chez les caucasiens. Sur le plan phénotypique, une sur-représentation des uvéites et une moindre prévalence du psoriasis sont rapportées. Les données comparatives sur la sévérité, essentiellement étasuniennes, restent contrastées et rapportent des disparités d’accès aux biothérapies entre afro-américains et caucasiens. La sous-représentation persistante des afrodescendants ainsi que l’absence de participation de l’Afrique subsaharienne dans les essais cliniques internationaux de la spondyloarthrite soulignent l’enjeu d’une recherche plus inclusive nécessaire à la génération de données robustes et représentatives de ces populations spécifiques. Although the evolution of classification criteria for spondyloarthritis has improved the identification of early disease, their implementation remains contingent on access to imaging (radiography or MRI) and HLA-B27 typing. Additionally, the hypothesis that ethnic variation in the distribution of HLA-B27 contributes to lower spondyloarthritis prevalence in specific populations has emerged. Consequently, the lower spondyloarthritis prevalence reported in populations of African ancestry is often attributed to the low population frequency of HLA-B27.This review provides context for the epidemiological, clinical, biological, and genetic data on spondyloarthritis in sub-Saharan Africa and among the Black African diaspora. In sub-Saharan Africa, published spondyloarthritis cohorts have increased in size over time. There has also been a shift from studies focusing predominantly on ankylosing spondylitis to studies dominated by reactive arthritis, undifferentiated spondyloarthritis, and, in some settings, HIV-associated arthritis. From a genetic standpoint, HLA-B27 is uncommon in the general sub-Saharan African population, and its association with spondyloarthritis appears modest. Alternative HLA signals, including HLA-B14:03 and HLA-B57:03, have also been reported. In the Black African diaspora, HLA-B27 positivity remains lower among individuals of African descent than among Caucasians. Several comparative studies report a higher frequency of uveitis and a lower prevalence of psoriasis. Evidence regarding disease severity, mostly from North America, is inconsistent, and disparities in access to biologic therapies have been documented between African American and Caucasian patients. Finally, the persistent underrepresentation of Afro-descendant populations and the absence of sub-Saharan Africa recruitment in spondyloarthritis clinical trials underscore the necessity of more inclusive research to produce representative and evidence-based data for these populations.

Central nervous system tumors present significant diagnostic and therapeutic challenges, as WHO histomolecular prognostic criteria are not always optimal. Decision-making increasingly relies on multidisciplinary team meetings (MDTs), which require highly qualified specialists. We aimed to assess available human resources and propose a framework for subregional collaboration through a West African neuro-oncology MDT. A multicenter descriptive study was conducted via an online questionnaire from April 13 to June 15, 2025, involving 35 healthcare professionals from nine West African countries. Participants included 45.7% neurosurgeons, over 57% with <3 years' experience. Most managed <100 patients/year, and 90% performed <100 tumor excisions. Awake surgery and stereotactic biopsy were rare. Access to chemotherapy, pathology, immunohistochemistry, and molecular biology was reported by 83%, 80%, 51%, and 14% of respondents, respectively. Median turnaround time was about 3 weeks for histopathology and about 1 month for immunohistochemistry. Clinical trial access was available to 26%. Neurosurgeon density was <1 per million inhabitants, peaking in Senegal (1 per 700,000). Only 34% reported functional MDTs. Nearly all participants (95%) supported establishing a subregional network with regular online MDTs (monthly or bimonthly) and a specialized interuniversity degree. MDTs are essential in neuro-oncology, enabling individualized therapeutic planning. Given critical workforce shortages in West Africa, a subregional collaborative MDT network could optimize patient care, enhance resource sharing, and standardize management across the region.

The complete mitochondrial genome of the invasive terrestrial nemertean Geonemertes pelaensis Semper, 1863 (Nemertea: Prosorhochmidae) was sequenced from two specimens collected in geographically distant French overseas territories-Martinique in the Caribbean and New Caledonia in the South-West Pacific. In both specimens, the mitogenome contained 13 protein-coding genes, two rRNA genes, and 21 tRNA genes, and was unusually large, approaching 32kb. The two genomes differed by only four single nucleotide polymorphisms and one indel. A comparison with 22 cox1 sequences available in GenBank confirmed this high level of genetic conservation, suggesting a recent introduction from related source populations. The extraordinary length of the mitogenome was largely attributable to two extended regions comprising only tRNA genes and long intergenic sequences. These results were contrasted with data from an unpublished SRA sequencing project (SRS20559370) of an unlocalized specimen identified as G. pelaensis; its reconstructed mitogenome was only 18kb in length (14kb shorter) and showed extensive sequence divergence. Phylogenetic analyses placed this specimen as the sister lineage to G. pelaensis, highlighting the need for further investigation of this taxon. In the Martinique specimen, several NUMTs (nuclear mitochondrial pseudogenes) were also detected, which could complicate future studies relying solely on Sanger sequencing. Sequencing additionally revealed prey DNA from the gut contents of both worms: the New Caledonian specimen had consumed an unidentified noctuid moth, while the Martinique specimen had likely fed on the invasive cockroach Periplaneta australasiae (Fabricius, 1775), itself an introduced species.

Chemoresistance remains a major obstacle to effective treatment and durable remission in leukemia patients. Although initial responses to chemotherapy are often favorable, relapse frequently occurs due to the emergence of drug-resistant malignant clones. Resistance mechanisms may be intrinsic or acquired and involve drug efflux, impaired apoptosis, enhanced DNA repair, epigenetic alterations, dysregulated signaling pathways, and microenvironmental interactions. A central mediator of multidrug resistance is the ATP-binding cassette (ABC) transporter family, particularly ABCB1 (also known as P-glycoprotein or MDR-1), which actively exports chemotherapeutic agents such as etoposide, doxorubicin, and vincristine, thereby reducing intracellular drug accumulation. Adult T-cell Leukemia/Lymphoma (ATLL), an aggressive malignancy caused by Human T-cell Leukemia Virus type 1 (HTLV-1), is characterized by poor prognosis and marked resistance to chemotherapy. Despite the recent approval of novel therapeutic agents, treatment outcomes remain unsatisfactory, largely due to both inherent and acquired chemoresistance. Overexpression of ABCB1 has been identified as a key mechanism contributing to multidrug resistance in ATLL. We compared the expression profiles of ABC transporter genes in CD8⁺-depleted peripheral blood mononuclear cells (PBMCs) from HTLV-1 asymptomatic carriers and patients with acute ATLL. To investigate the role of the viral transactivator Tax in regulating ABCB1 expression, we used HuT78 and JPX9 T-cell lines. Furthermore, Tax expression was reactivated in CD8⁺-depleted PBMCs from acute ATLL patients using valproic acid, and subsequent changes in ABCB1 expression and chemosensitivity to etoposide and doxorubicin were assessed. We found that ABCB1 expression was significantly upregulated in CD8⁺-depleted PBMCs from patients with acute ATLL compared to asymptomatic HTLV-1 carriers. In contrast, expression of the viral protein Tax in HuT78 and JPX9 cell lines resulted in decreased ABCB1 levels. Reactivation of Tax expression using valproic acid in primary ATLL samples confirmed that Tax downregulates ABCB1 expression. Importantly, Tax reactivation restored sensitivity of ATLL cells to chemotherapeutic agents, including etoposide and doxorubicin. Our findings identify ABCB1 overexpression as a major contributor to chemoresistance in acute ATLL and demonstrate that the viral protein Tax negatively regulates ABCB1 expression. These results suggest that reactivation of Tax may reduce drug efflux capacity and restore chemosensitivity in resistant ATLL cells. Collectively, this study provides a rationale for exploring a “Tax-based shock-andkill” strategy as a potential therapeutic approach to overcome chemoresistance in ATLL.

Galactia nummularia was rediscovered in 2021 in Saint Martin after a long absence of contemporary records. Recent occurrences have also been reported in Anguilla and Saint Barthélemy. Initially described from an incomplete specimen, the species appears to exhibit marked morphological variability in its leaves in response to ecological conditions, making its identification challenging. These new observations, supported by specimen collections, have allowed for an update of both its description and biogeographical status.

ObjectivesOlder adults transitioning to nursing homes face challenges in adapting to a new environment and imposed lifestyle changes. This study aimed to identify factors associated with poor nursing home adjustment and to assess their impact on 1-year mortality.Design and settingsThis study is a secondary analysis of the KArukera Study of Ageing in ‘Établissement d'Hébergement pour Personnes Agées Dépendantes’ (EHPAD) (KASEHPAD) cohort, a prospective observational study conducted over 1 year in six nursing homes in the French Caribbean.Participants159 older adults (aged 60 years or older) living in nursing homes who were able to complete the self-administered adaptation scale.Main outcome measuresNursing home adjustment was assessed at baseline using the adaptation scale for older adults to their residence (EAPAR). Bivariate analysis was used to assess associations between adjustment status and sociodemographic or clinical characteristics at baseline. Poisson regressions were used to assess the relationship between 1-year mortality and adjustment status.ResultsA total of 159 older adults (mean age: 79.6 years; male/female ratio: 84/75) were included. The mean length of stay was 4.1 years. Among older adults, 78 (49.1%) were classified as poorly adapted. Age, gender, education level, dependency, cognition and comorbidities were not significantly associated with poor adjustment. In contrast, depressive symptoms, lower social support, lower health-related quality of life, lower subjective quality of life, malnutrition and sleep disturbances were associated with poor adjustment. After 12 months, 14 deaths (17.9%) occurred in the poor adjustment group, compared with 4 (4.9%) in the no major adjustment difficulties group (adjusted relative risk for age, gender and baseline activities of daily living score=4.64 (95% CI 1.53 to 17.5; p=0011).ConclusionsIn a sample of older adults with moderate cognitive impairment, poor adjustment to nursing home was associated with depressive symptomatology and increased 1-year mortality. The issue of adjustment in nursing homes represents an emerging research area that warrants further investigation through dedicated interventional studies.Trial registration numberNCT04587466.