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1.
Ann Bot ; 132(2): 293-318, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37439499

RESUMO

BACKGROUND AND AIMS: The Lythraceae are a mainly subtropical to tropical family of the order Myrtales with 28 currently accepted genera and approximately 600 species. There is currently no well-supported phylogenetic and biogeographical hypothesis of the Lythraceae incorporating all currently accepted genera, which we sought to provide. METHODS: Plastomes of representative species of 18 distinct Lythraceae genera were sequenced and annotated. Together with existing sequences, plastomes of all 28 currently accepted genera in the Lythraceae were brought together for the first time. The plastomes were aligned and a Bayesian phylogenetic hypothesis was produced. We then conducted a time-calibrated Bayesian analysis and a biogeographical analysis. KEY RESULTS: Plastome-based Bayesian and maximum-likelihood phylogenetic trees are generally congruent with recent nuclear phylogenomic data and resolve two deeply branching major clades in the Lythraceae. One major clade concentrates shrubby and arboreal South American and African genera that inhabit seasonally dry environments, with larger, often winged seeds, adapted to dispersal by the wind. The second major clade concentrates North American, Asian, African and several near-cosmopolitan herbaceous, shrubby and arboreal genera, often inhabiting humid or aquatic environments, with smaller seeds possessing structures that facilitate dispersal by water. CONCLUSIONS: We hypothesize that the Lythraceae dispersed early in the Late Cretaceous from South American to North American continents, with subsequent expansion in the Late Cretaceous of a North American lineage through Laurasia to Africa via a boreotropical route. Two later expansions of South American clades to Africa in the Palaeocene and Eocene, respectively, are also hypothesized. Transoceanic dispersal in the family is possibly facilitated by adaptations to aquatic environments that are common to many extant genera of the Lythraceae, where long-distance dispersal and vicariance may be invoked to explain several remarkable disjunct distributions in Lythraceae clades.


Assuntos
Lythraceae , Filogenia , Filogeografia , Teorema de Bayes , África
2.
New Phytol ; 233(1): 534-545, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34537964

RESUMO

The genus Manihot, with around 120 known species, is native to a wide range of habitats and regions in the tropical and subtropical Americas. Its high species richness and recent diversification only c. 6 million years ago have significantly complicated previous phylogenetic analyses. Several basic elements of Manihot evolutionary history therefore remain unresolved. Here, we conduct a comprehensive phylogenomic analysis of Manihot, focusing on exhaustive sampling of South American taxa. We find that two recently described species from northeast Brazil's Atlantic Forest were the earliest to diverge, strongly suggesting a South American common ancestor of Manihot. Ancestral state reconstruction indicates early Manihot diversification in dry forests, with numerous independent episodes of new habitat colonization, including into savannas and rainforests within South America. We identify the closest wild relatives to Manihot esculenta, including the crop cassava, and we quantify extensive wild introgression into the cassava gene pool from at least five wild species, including Manihot glaziovii, a species used widely in breeding programs. Finally, we show that this wild-to-crop introgression substantially shapes the mutation load in cassava. Our findings provide a detailed case study for neotropical evolutionary history in a diverse and widespread group, and a robust phylogenomic framework for future Manihot and cassava research.


Assuntos
Manihot , Evolução Biológica , Pool Gênico , Manihot/genética , Filogenia , América do Sul
3.
Artigo em Inglês | MEDLINE | ID: mdl-23133318

RESUMO

BACKGROUND: Osteoporosis and cardiovascular disease are interconnected entities with pathophysiological similarities. Bisphosphonates are therapeutic options available for resorptive bone diseases; however, experimental evidence has demonstrated a role for bisphosphonates in the inhibition of atherogenesis. METHODS: A systematic review of the vascular effects of bisphosphonates on atherosclerosis was performed. Vascular effects were evaluated by the thickening of the intima-media of carotid arteries and calcification of the coronary and aorta arteries. Electronic databases PubMed, The Cochrane Library, and Embase from January 1980 to May 2011 were searched. RESULTS: Of 169 potentially relevant articles, 9 clinical trials were selected. Two articles showed the benefit of the use of etidronate (-0.038 mm, P < 0.005) and alendronate (-0.025 mm, P < 0.05) on carotid artery intima-media thickening (CIMT) after one year. One article found no changes associated with the use of alendronate. The use of risedronate was associated with a reduction of plaque score on the carotid arteries (decrease of 1% at 1 year, P = 0.015). Of those studies that evaluated the effect on coronary artery calcification (CAC), the results are conflicting: one study showed no changes with use of etidronate and in another, etidronate resulted in inhibition of the process of CAC after 1 year of follow-up (-372 mm(3) in CAC score, P < 0.01). Three studies showed positive effects of etidronate on the aortic calcificaton (AC) score, showing no effect with use of ibandronate, and another showed a inhibition in the progression of the abdominal AC score with use of risendronate (P = 0.043). CONCLUSION: Bisphosphonates seem to have an inhibitory effect on the atherosclerotic process; however, larger placebo-controlled studies are needed to better clarify this issue.

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