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1.
Sci Data ; 10(1): 327, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37236921

RESUMO

The Checklist of the Vascular Plants of the Republic of Guinea (CVPRG) is a specimen-based, expert-validated knowledge product, which provides a concise synthesis and overview of current knowledge on 3901 vascular plant species documented from Guinea (Conakry), West Africa, including their accepted names and synonyms, as well as their distribution and status within Guinea (indigenous or introduced, endemic or not). The CVPRG is generated automatically from the Guinea Collections Database and the Guinea Names Backbone Database, both developed and maintained at the Royal Botanic Gardens, Kew, in collaboration with the staff of the National Herbarium of Guinea. A total of 3505 indigenous vascular plant species are reported of which 3328 are flowering plants (angiosperms); this represents a 26% increase in known indigenous angiosperms since the last floristic overview. Intended as a reference for scientists documenting the diversity and distribution of the Guinea flora, the CVPRG will also inform those seeking to safeguard the rich plant diversity of Guinea and the societal, ecological and economic benefits accruing from these biological resources.


Assuntos
Magnoliopsida , Traqueófitas , Guiné , Plantas
2.
Front Plant Sci ; 13: 889988, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35909765

RESUMO

Convolvulaceae is a family of c. 2,000 species, distributed across 60 currently recognized genera. It includes species of high economic importance, such as the crop sweet potato (Ipomoea batatas L.), the ornamental morning glories (Ipomoea L.), bindweeds (Convolvulus L.), and dodders, the parasitic vines (Cuscuta L.). Earlier phylogenetic studies, based predominantly on chloroplast markers or a single nuclear region, have provided a framework for systematic studies of the family, but uncertainty remains at the level of the relationships among subfamilies, tribes, and genera, hindering evolutionary inferences and taxonomic advances. One of the enduring enigmas has been the relationship of Cuscuta to the rest of Convolvulaceae. Other examples of unresolved issues include the monophyly and relationships within Merremieae, the "bifid-style" clade (Dicranostyloideae), as well as the relative positions of Erycibe Roxb. and Cardiochlamyeae. In this study, we explore a large dataset of nuclear genes generated using Angiosperms353 kit, as a contribution to resolving some of these remaining phylogenetic uncertainties within Convolvulaceae. For the first time, a strongly supported backbone of the family is provided. Cuscuta is confirmed to belong within family Convolvulaceae. "Merremieae," in their former tribal circumscription, are recovered as non-monophyletic, with the unexpected placement of Distimake Raf. as sister to the clade that contains Ipomoeeae and Decalobanthus Ooststr., and Convolvuleae nested within the remaining "Merremieae." The monophyly of Dicranostyloideae, including Jacquemontia Choisy, is strongly supported, albeit novel relationships between genera are hypothesized, challenging the current tribal delimitation. The exact placements of Erycibe and Cuscuta remain uncertain, requiring further investigation. Our study explores the benefits and limitations of increasing sequence data in resolving higher-level relationships within Convolvulaceae, and highlights the need for expanded taxonomic sampling, to facilitate a much-needed revised classification of the family.

3.
PhytoKeys ; 136: 45-96, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31866738

RESUMO

An annotated checklist of the 271 strict-endemic taxa (235 species) and 387 near-endemic taxa (337 species) of vascular plants in Mozambique is provided. Together, these taxa constitute c. 9.3% of the total currently known flora of Mozambique and include five strict-endemic genera (Baptorhachis, Emicocarpus, Gyrodoma, Icuria and Micklethwaitia) and two near-endemic genera (Triceratella and Oligophyton). The mean year of first publication of these taxa is 1959, with a marked increase in description noted following the onset of the two major regional floristic programmes, the "Flora of Tropical East Africa" and "Flora Zambesiaca", and an associated increase in botanical collecting effort. New taxa from Mozambique continue to be described at a significant rate, with 20 novelties described in 2018. Important plant families for endemic and near-endemic taxa include Fabaceae, Rubiaceae and Euphorbiaceae s.s. There is a high congruence between species-rich plant families and endemism with the notable exceptions of the Poaceae, which is the second-most species rich plant family, but outside of the top ten families in terms of endemism, and the Euphorbiaceae, which is the seventh-most species rich plant family, but third in terms of endemism. A wide range of life-forms are represented in the endemic and near-endemic flora, with 49% being herbaceous or having herbaceous forms and 55% being woody or having woody forms. Manica Province is by far the richest locality for near-endemic taxa, highlighting the importance of the cross-border Chimanimani-Nyanga (Manica) Highlands shared with Zimbabwe. A total of 69% of taxa can be assigned to one of four cross-border Centres of Endemism: the Rovuma Centre, the Maputaland Centre sensu lato, and the two mountain blocks, Chimanimani-Nyanga and Mulanje-Namuli-Ribaue. Approximately 50% of taxa have been assessed for their extinction risk and, of these, just over half are globally threatened (57% for strict-endemics), with a further 10% (17% for strict-endemics) currently considered to be Data Deficient, highlighting the urgent need for targeted conservation of Mozambique's unique flora. This dataset will be a key resource for ongoing efforts to identify "Important Plant Areas - IPAs" in Mozambique, and to promote the conservation and sustainable management of these critical sites and species, thus enabling Mozambique to meet its commitments under the Convention on Biological Diversity (CBD).


ResumoApresenta-se a lista das plantas vasculares de Moçambique, que compreende 271 taxa endémicos (235 espécies) e 387 taxa quase-endémicos (337 espécies). Estes taxa constituem cerca de 9,3% da flora total actualmente conhecida em Moçambique e incluem cinco géneros estritamente endémicos (Baptorhachis, Emicocarpus, Gyrodoma, Icuria e Micklethwaitia) e dois géneros quase-endémicos (Triceratella e Oligophyton). O ano médio das primeiras publicações destes taxa é 1959. Um aumento significativo na descrição de espécies novas foi verificado, relacionado com o início de dois projectos regionais, a "Flora of Tropical East Africa" e a "Flora Zambesiaca", permitindo um esforço maior de colheitas botânicas. Novos taxa têm vindo a ser descritos a um ritmo significativo, com 20 novas espécies descritas em 2018 para a flora de Moçambique. As famílias Fabaceae, Rubiaceae e Euphorbiaceae, incluem importantes taxa endémicos e quase-endémicos. Existe uma estreita relação entre as famílias de plantas com elevado número de espécies e o grau de endemismo, excepção feita às Poaceae, que embora seja a segunda família mais rica em espécies não se posiciona no grupo das dez principais famílias em termos de endemismo. Por outro lado a família Euphorbiaceae, que é a sétima mais rica em espécies, posiciona-se em terceiro lugar quanto ao número de endemismo. A flora endémica apresenta diferentes formas de vida, sendo 49% das espécies herbáceas e 55% lenhosas. A Província de Manica é o local mais rico em taxa quase-endémicos, realçando assim a importância da área transfronteiriça Chimanimani-Nyanga (Manica) entre Moçambique e Zimbabwe. Refira-se ainda que 69% dos taxa encontra-se num dos quatro centros de endemismo transfronteiriços: o Centro do Rovuma, o Centro de Maputaland sensu lato e nas regiões montanhosas de Chimanimani-Nyanga e Mulanje-Namuli-Ribáuè. Cerca de 50% dos taxa foram avaliados quanto ao risco de extinção, estando mais da metade ameaçados globalmente (57% de endemismos) e 10% (17% de endemismos) foram incluídos na categoria Informação Insuficiente (DD), revelando que a maioria das plantas endémicas de Moçambique necessitam de conservação urgente. Este estudo fornece novos dados indispensáveis à identificação das "Áreas Importantes de Plantas ­ IPAs" em Moçambique, contribuindo ainda para implementar as estratégias de conservação anteriormente estabelecidas pela Convenção sobre a Diversidade Biológica (CBD).

4.
PhytoKeys ; 133: 115-132, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31662617

RESUMO

Synsepalum chimanimani S.Rokni & I.Darbysh., sp. nov., a small tree endemic to the forests of the southern foothills of the Chimanimani Mountains of Mozambique and Zimbabwe, is described and illustrated. The differences in morphology and distribution between the new species and the related S. kaessneri and S. muelleri, with which it has been confused, are clarified. The new species is globally Endangered due to ongoing habitat loss within its restricted range. The botanical importance and conservation of the Chimanimani foothills is also discussed, and they are highlighted as a candidate Important Plant Area.

5.
Diabetes ; 61(3): 683-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22315309

RESUMO

The incidence of type 1 diabetes has increased rapidly over recent decades, particularly in young children. We aimed to determine whether this rise was associated with changes in patterns of humoral islet autoimmunity at diagnosis. Autoantibodies to insulin (IAA), GAD (GADA), islet antigen-2 (IA-2A), and zinc transporter 8 (ZnT8A) were measured by radioimmunoassay in sera collected from children and young adults with newly diagnosed type 1 diabetes between 1985 and 2002. The influence of date of diagnosis on prevalence and level of autoantibodies was investigated by logistic regression with adjustment for age and HLA class II genetic risk. Prevalence of IA-2A and ZnT8A increased significantly over the period studied, and this was mirrored by raised levels of IA-2A, ZnT8A, and IA-2ß autoantibodies (IA-2ßA). IAA and GADA prevalence and levels did not change. Increases in IA-2A, ZnT8A, and IA-2ßA at diagnosis during a period of rising incidence suggest that the process leading to type 1 diabetes is now characterized by a more intense humoral autoimmune response. Understanding how changes in environment or lifestyle alter the humoral autoimmune response to islet antigens should help explain why the incidence of type 1 diabetes is increasing and may suggest new strategies for preventing disease.


Assuntos
Autoanticorpos/sangue , Diabetes Mellitus Tipo 1/imunologia , Adolescente , Adulto , Proteínas de Transporte de Cátions/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Imunofenotipagem , Lactente , Modelos Logísticos , Masculino , Transportador 8 de Zinco
6.
J Clin Endocrinol Metab ; 97(2): 632-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22162482

RESUMO

CONTEXT: Antibodies to islet autoantigens are detectable many years before clinical onset of type 1 diabetes and can be used to identify individuals at increased risk of diabetes. Zinc transporter 8 is a recently identified islet autoantigen. OBJECTIVE: Our aim was to determine whether addition of zinc transporter 8 autoantibodies (ZnT8A) improved prediction of type 1 diabetes in a well-characterized cohort of islet cell antibody (ICA)-positive first-degree relatives. We were particularly interested in the role of ZnT8A in prediction in antibody-positive relatives with intermediate and low overall risk of diabetes. PARTICIPANTS AND METHODS: ZnT8A were assayed in baseline samples from 526 ICA-positive first-degree relatives randomized in the European Nicotinamide Diabetes Intervention Trial. Antibodies to insulin, glutamate decarboxylase, islet antigen-2 (IA-2A) and IA-2ß (IA-2ßA), and human leukocyte antigen type had been previously determined. Risk of diabetes was assessed by survival analysis. RESULTS: Of 221 ZnT8A-positive individuals, 113 developed diabetes during follow-up (5-yr cumulative risk, 55%). In multivariate models based on other autoantibodies, ZnT8A improved prediction in relatives at low genetic risk of diabetes (P = 0.030) and over age 20 yr (P = 0.026), but not in those with ICA alone or with one additional autoantibody (P = 0.696), IA-2A-negative relatives (P = 0.361), those at high or intermediate genetic risk, or younger relatives. CONCLUSIONS: ZnT8A are useful additional risk markers in relatives at low genetic risk of diabetes and older individuals, but they add relatively little in younger populations because of the precise prediction possible with current autoantibody combinations.


Assuntos
Autoanticorpos/fisiologia , Proteínas de Transporte de Cátions/imunologia , Diabetes Mellitus Tipo 1/diagnóstico , Técnicas de Diagnóstico Endócrino , Família , Adolescente , Adulto , Autoanticorpos/sangue , Criança , Estudos de Coortes , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/imunologia , Europa (Continente) , Feminino , Seguimentos , Humanos , Masculino , Niacinamida/uso terapêutico , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto Jovem , Transportador 8 de Zinco
7.
J Immunol Methods ; 362(1-2): 199-203, 2010 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-20833177

RESUMO

Insulin autoantibodies (IAA) are usually the first risk-markers detected during the type 1 diabetes prodrome, but precise measurement is difficult as insulin binding is often low. Non-specific binding (NSB) of (125)I-labelled insulin necessitates competitive displacement with unlabelled insulin to demonstrate specificity. NSB varies with different batches of label, suggesting that it is caused by impurities in the label. Addition of bovine serum albumin (BSA) can reduce NSB, so we investigated whether BSA antibodies cause lack of specificity in IAA assays. Samples from patients with newly-diagnosed type 1 diabetes, healthy schoolchildren previously found to have raised (125)I-insulin binding (≥ 0.4 units) and IAA-negative schoolchildren were re-assayed for IAA by radiobinding microassay using commercial (125)I-insulin with and without 1g/dl BSA added to the buffer. Of 100 patients, 68 were IAA-positive on re-assay with BSA compared to 72 without BSA (p=0.125). Of 154 schoolchildren who previously had raised (125)I-insulin binding, only 45 had (125)I-insulin binding ≥ 0.4 units on re-assay with BSA compared to 90 without BSA (p<0.001). Following competitive displacement with unlabelled insulin, 40 were IAA-positive with BSA compared to 48 without BSA (p=0.02). No IAA-negative schoolchildren were IAA-positive on re-assay. Levels of NSB were associated with antibodies binding (125)I-BSA and purification of labelled insulin reduced NSB. Addition of BSA to assay buffer improves the screening efficiency of the IAA assay without reducing disease sensitivity in patients. High titre BSA antibodies interfere with IAA measurement because of (125)I-BSA present in some insulin labels. Improved purification of insulin labels should obviate the need for competitive displacement.


Assuntos
Autoanticorpos/imunologia , Diabetes Mellitus Tipo 1/imunologia , Insulina/imunologia , Soroalbumina Bovina/imunologia , Adolescente , Adulto , Animais , Autoanticorpos/sangue , Bovinos , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/sangue , Humanos , Lactente , Masculino , Radioimunoensaio , Soroalbumina Bovina/química
8.
J Immunol Methods ; 351(1-2): 75-9, 2009 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-19837075

RESUMO

Autoantibodies to islet antigen 2 (IA-2A) are important markers for predicting diabetes in children and young adults. Harmonization of IA-2A assay measurement is essential if results from different laboratories are to be compared. We investigated whether sodium azide, a bacteriostatic agent added to some assays, could affect IA-2A binding and thereby contribute to differences in IA-2A measurement between laboratories. Addition of 0.1% azide to assay buffer was found to reduce median IA-2A binding of 18 selected sera from IA-2A positive patients with type 1 diabetes and their relatives by 41% (range, 78 to -33%, p<0.001). The effect on binding was epitope specific; median IA-2A binding by 14 sera with antibodies to the protein tyrosine phosphatase region of IA-2 was reduced by 48% (range, 11 to 78%, p<0.001), while binding by 4 sera with antibodies specific to only the juxtamembrane region of IA-2 showed no change (median increase 16% (range 6 to 33%, p=0.125). When the Tween-20 concentration was reduced from 1% to 0.15% the median reduction in IA-2A binding with azide by the 18 sera was only 10% (range, -12 to 41%, p<0.001). Tween-20 also exerted an independent effect, since median IA-2A binding increased by 23% (range 3% to 86%, p<0.001) when Tween-20 concentration was reduced from 1% to 0.15% in the absence of azide. We conclude that common assay reagents such as azide and Tween-20 can strongly influence IA-2A binding in an epitope-related manner, and their use may explain some of the differences between laboratories in IA-2A measurement.


Assuntos
Diabetes Mellitus Tipo 1/diagnóstico , Epitopos/metabolismo , Ensaio Radioligante , Proteínas Tirosina Fosfatases Classe 8 Semelhantes a Receptores/imunologia , Proteínas Tirosina Fosfatases Classe 8 Semelhantes a Receptores/metabolismo , Autoanticorpos/sangue , Azidas , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/imunologia , Epitopos/imunologia , Humanos , Polissorbatos , Ligação Proteica , Reprodutibilidade dos Testes
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