30 research outputs found
Global Retinoblastoma Presentation and Analysis by National Income Level.
Importance: Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale. Objectives: To report the retinoblastoma stage at diagnosis in patients across the world during a single year, to investigate associations between clinical variables and national income level, and to investigate risk factors for advanced disease at diagnosis. Design, Setting, and Participants: A total of 278 retinoblastoma treatment centers were recruited from June 2017 through December 2018 to participate in a cross-sectional analysis of treatment-naive patients with retinoblastoma who were diagnosed in 2017. Main Outcomes and Measures: Age at presentation, proportion of familial history of retinoblastoma, and tumor stage and metastasis. Results: The cohort included 4351 new patients from 153 countries; the median age at diagnosis was 30.5 (interquartile range, 18.3-45.9) months, and 1976 patients (45.4%) were female. Most patients (nâ=â3685 [84.7%]) were from low- and middle-income countries (LMICs). Globally, the most common indication for referral was leukocoria (nâ=â2638 [62.8%]), followed by strabismus (nâ=â429 [10.2%]) and proptosis (nâ=â309 [7.4%]). Patients from high-income countries (HICs) were diagnosed at a median age of 14.1 months, with 656 of 666 (98.5%) patients having intraocular retinoblastoma and 2 (0.3%) having metastasis. Patients from low-income countries were diagnosed at a median age of 30.5 months, with 256 of 521 (49.1%) having extraocular retinoblastoma and 94 of 498 (18.9%) having metastasis. Lower national income level was associated with older presentation age, higher proportion of locally advanced disease and distant metastasis, and smaller proportion of familial history of retinoblastoma. Advanced disease at diagnosis was more common in LMICs even after adjusting for age (odds ratio for low-income countries vs upper-middle-income countries and HICs, 17.92 [95% CI, 12.94-24.80], and for lower-middle-income countries vs upper-middle-income countries and HICs, 5.74 [95% CI, 4.30-7.68]). Conclusions and Relevance: This study is estimated to have included more than half of all new retinoblastoma cases worldwide in 2017. Children from LMICs, where the main global retinoblastoma burden lies, presented at an older age with more advanced disease and demonstrated a smaller proportion of familial history of retinoblastoma, likely because many do not reach a childbearing age. Given that retinoblastoma is curable, these data are concerning and mandate intervention at national and international levels. Further studies are needed to investigate factors, other than age at presentation, that may be associated with advanced disease in LMICs
Genesis and development of an interfluvial peatland in the central Congo Basin since the Late Pleistocene
No abstract available
Genesis and development of an interfluvial peatland in the central Congo Basin since the Late Pleistocene
The core collection fieldwork was funded by the Royal Society, to S.L.L., Philip Leverhulme Prize to S.L.L. and a NERC CASE award to S.L.L. and G.C.D. The laboratory analysis, data analysis and write-up was funded by CongoPeat, a NERC Large Grant (NE/R016860/1) to S.L.L., I.T.L., A.B., S.E.P., P.G., supporting D.H., G.T., G.C.D., W.H., G.E.B., and Y.E.B.; and NERC Radiocarbon Facility grant (alloc. no. 1688.0313 and 1797.0414) to I.T.L., S.L.L. and G.C.D. Y. G. was supported by the Agence Nationale de la Recherche (ANR) grant ANR-19-CE01-0022. E.S. was supported by the Deutsche Forschungsgemeinschaft (DFG) grant SCHE 903/19â1 and the DFG-Cluster of Excellence âThe Ocean in the Earth Systemâ at MARUM.The central Congo Basin contains the largest known peatland complex in the tropics. Here we present a detailed multi-proxy record from a peat core, CEN-17.4, from the centre of a 45 km wide interfluvial peatland (Ekolongouma), the first record of its kind from the central Congo peatlands. We use pollen, charcoal, sedimentological and geochemical data to reconstruct the site's history from the late Pleistocene to the present day. Peat began accumulating at the centre of the peatland âŒ19,600 cal BP (âŒ17,500â20,400 cal BP, 95% confidence interval), and between âŒ9500 (9430â9535 cal BP) and 10,500 (10,310â10,660 cal BP) cal BP towards the margins. Pollen data from the peatland centre show that an initial grass- and sedge-dominated vegetation, which burned frequently, was replaced by a Manilkara-type dominated flooded forest at âŒ12,640 cal BP, replaced in turn by a more mixed swamp forest at âŒ9670 cal BP. Mixed swamp forest vegetation has persisted to the present day, with variations in composition and canopy openness likely caused at least in part by changes in palaeo-precipitation. Stable isotope data (ÎŽDn-C29-v&icecorr) indicate a large reduction in precipitation beginning âŒ5000 and peaking âŒ2000 cal BP, associated with the near-complete mineralization of several metres of previously accumulated peat and with a transition to a drier, more heliophilic swamp forest assemblage, likely with a more open canopy. Although the peatland and associated vegetation recovered from this perturbation, the strong response to this climatic event underlines the ecosystem's sensitivity to changes in precipitation. We find no conclusive evidence for anthropogenic activity in our record; charcoal is abundant only in the Pleistocene part of the record and may reflect natural rather than anthropogenic fires. We conclude that autogenic succession and variation in the amount and seasonality of precipitation have been the most important drivers of ecological change in this peatland since the late Pleistocene.Publisher PDFPeer reviewe
Genesis and development of an interfluvial peatland in the central Congo Basin since the Late Pleistocene
The central Congo Basin contains the largest known peatland complex in the tropics. Here we present a detailed multi-proxy record from a peat core, CEN-17.4, from the centre of a 45 km wide interfluvial peatland (Ekolongouma), the first record of its kind from the central Congo peatlands. We use pollen, charcoal, sedimentological and geochemical data to reconstruct the site's history from the late Pleistocene to the present day. Peat began accumulating at the centre of the peatland âŒ19,600 cal BP (âŒ17,500â20,400 cal BP, 95% confidence interval), and between âŒ9500 (9430â9535 cal BP) and 10,500 (10,310â10,660 cal BP) cal BP towards the margins. Pollen data from the peatland centre show that an initial grass- and sedge-dominated vegetation, which burned frequently, was replaced by a Manilkara-type dominated flooded forest at âŒ12,640 cal BP, replaced in turn by a more mixed swamp forest at âŒ9670 cal BP. Mixed swamp forest vegetation has persisted to the present day, with variations in composition and canopy openness likely caused at least in part by changes in palaeo-precipitation. Stable isotope data (ÎŽDn-C29-v&icecorr) indicate a large reduction in precipitation beginning âŒ5000 and peaking âŒ2000 cal BP, associated with the near-complete mineralization of several metres of previously accumulated peat and with a transition to a drier, more heliophilic swamp forest assemblage, likely with a more open canopy. Although the peatland and associated vegetation recovered from this perturbation, the strong response to this climatic event underlines the ecosystem's sensitivity to changes in precipitation. We find no conclusive evidence for anthropogenic activity in our record; charcoal is abundant only in the Pleistocene part of the record and may reflect natural rather than anthropogenic fires. We conclude that autogenic succession and variation in the amount and seasonality of precipitation have been the most important drivers of ecological change in this peatland since the late Pleistocene
Palaeo-environmental data from the central Congo peatlands, Likouala Department, Republic of Congo
Compound-specific stable carbon and hydrogen isotopes of plant-wax derived long-chain n-alkanes of core CEN-17.4 Bulk organic parameters of core CEN-17.4 Rock-eval data of core CEN-17.4 Pollen data of core CEN-17.4 Rock-eval data of core EKG02 Rock-eval data of core EKG0