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1.
Plants (Basel) ; 13(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38931086

RESUMO

Discussing homology relationships among secretory structures remains a relatively underexplored area in botanical research. These structures are widely dispersed within Malpighiales, one of the largest orders of eudicots. Within Malpighiales, both extranuptial and nuptial nectaries are present, and they do not seem homoplastic or share evolutionary connections. Particularly in Malpighiaceae, extensive research has focused on the ecological interactions mediated by glands. Botanists largely agree that elaiophores in sepals of Neotropical Malpighiaceae have evolved from extrafloral nectaries on leaves. However, the evolutionary origin of elaiophores has yet to be thoroughly examined, particularly in comparison to outgroups. This study provides empirical evidence on the ontogeny of elaiophores and investigates their evolutionary origins and homology relationships across different lineages of Malpighiales using comparative anatomy. Our findings suggest that elaiophores are likely homologous to extranuptial nectaries found in sepals of other Malpighiales lineages, originating from nectaries on leaves. This discussion is a starting point for future studies exploring the evolution of nectaries found in flowers, whether extranuptial or nuptial, and their potential origins from nectaries in vegetative organs such as leaves. Understanding these relationships could shed light on the selective pressures influencing floral morphologies.

2.
Molecules ; 28(8)2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37110673

RESUMO

Carbonyl compounds are widely explored in medicinal inorganic chemistry and have drawn attention due to their signaling functions in homeostasis. Carbon-monoxide-releasing molecules (CORMs) were developed with the purpose of keeping the CO inactive until its release in the intracellular environment, considering its biological relevance. However, for therapeutic applications, the mechanisms of photorelease and which electronic and structural variations influence its rates must be fully understood. In this work, four ligands containing a pyridine, a secondary amine, and a phenolic group with different substituents were used to prepare new Mn(I) carbonyl compounds. Structural and physicochemical characterization of these complexes was carried out and confirmed the proposed structures. X-ray diffractometry structures obtained for the four organometallic compounds revealed that the substituents in the phenolic ring promote only negligible distortions in their geometry. Furthermore, UV-Vis and IR kinetics showed the direct dependence of the electron-withdrawing or donating ability of the substituent group, indicating an influence of the phenol ring on the CO release mechanism. These differences in properties were also supported by theoretical studies at the DFT, TD-DFT, and bonding situation analyses (EDA-NOCV). Two methods were used to determine the CO release constants (kCO,old and kCO,new), where Mn-HbpaBr (1) had the greatest kCO by both methods (Kco,old = 2.36 × 10-3 s-1 and kCO,new = 2.37 × 10-3 s-1). Carbon monoxide release was also evaluated using the myoglobin assay, indicating the release of 1.248 to 1.827 carbon monoxides upon light irradiation.

3.
Sensors (Basel) ; 22(19)2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36236784

RESUMO

The purpose of this review is to aggregate technical information on existent optomechanical eye models (OME) described in the literature, for image quality assessment in different applications. Several physical eye models have been reviewed from peer-reviewed papers and patent applications. A typical eye model includes an artificial cornea, an intraocular lens or other lens to simulate the crystalline lens, an aperture as the pupil, and a posterior retinal surface, which may be connected to a light sensor. The interior of the eye model may be filled with a fluid to better emulate physiological conditions. The main focus of this review is the materials and physical characteristics used and the dimensional aspects of the main components including lenses, apertures, chambers, imaging sensors and filling medium. Various devices are described with their applications and technical details, which are systematically tabulated highlighting their main characteristics and applications. The models presented are detailed and discussed individually, and the features of different models are compared when applicable, highlighting strengths and limitations. In the end there is a brief discussion about the potential use of artificial eye models for industrial applications.


Assuntos
Lentes Intraoculares , Córnea , Humanos , Pupila/fisiologia
4.
PeerJ ; 10: e12937, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35194527

RESUMO

We describe three new species of Malpighiaceae that are endemic to central Brazil and related to the Heteropterys pannosa complex, a group of xylopodiferous, unbranched subshrubs with fruit in mericarps that have a strongly reduced or no dorsal wing. Heteropterys tocantinensis is more common in eastern Tocantins State and on the border with Bahia State, and there are a few records from Mato Grosso State. Heteropterys veadeirensis is restricted to northern Goiás State and H. walteri has a wider distribution, occurring in some municipalities in northern Goiás and southern Tocantins. Additionally, we also provide detailed redescriptions of H. pannosa and H. rosmarinifolia, the two previously known species in this complex. All species are considered Endangered (EN) based on IUCN criteria, especially due to the low area of occupancy. Illustrations, distribution maps, and information about phenology and habitat are also provided for all taxa.


Assuntos
Malpighiaceae , Animais , Brasil , Ecossistema
5.
Biodivers Data J ; 10: e75910, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35095296

RESUMO

BACKGROUND: The Atlantic Forest is one of the most threatened biomes in the world. Despite that, this biome still includes many areas that are poorly known floristically, including several protected areas, such as the "Floresta Nacional do Rio Preto" ("Flona do Rio Preto"), located in the Brazilian State of Espírito Santo. This study used a published vascular plant species list for this protected area from the "Catálogo de Plantas das Unidades de Conservação do Brasil" as the basis to synthesise the species richness, endemism, conservation and new species occurrences found in the "Flona do Rio Preto". NEW INFORMATION: The published list of vascular plants was based on field expeditions conducted between 2018 and 2020 and data obtained from herbarium collections available in online databases. Overall, 722 species were documented for the "Flona do Rio Preto", 711 of which are native to Brazil and 349 are endemic to the Atlantic Forest. In addition, 60 species are geographically disjunct between the Atlantic and the Amazon Forests. Most of the documented species are woody and more than 50% of these are trees. Twenty-three species are threatened (CR, EN and VU), while five are Data Deficient (DD). Thirty-two species are new records for the State of Espírito Santo. Our results expand the knowledge of the flora of the Atlantic Forest and provide support for the development of new conservation policies for this protected area.

6.
PhytoKeys ; 181: 49-64, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34566447

RESUMO

Tovomitopsis Planch. & Triana is a Brazilian Atlantic Forest endemic genus composed of two species: T.paniculata (Spreng.) Planch. & Triana and T.saldanhae Engl. An investigation was conducted to clarify the nomenclatural history of Tovomitopsis. We report the results of this investigation, provide an updated description of the genus, and propose lectotypes for T.paniculata and its synonyms: Tovomitafoliosa C.Presl and Tovomitapaniculata Cambess. We also propose lectotypes for T.saldanhae and for the new synonym Clusiaangustifolia Engl.

7.
Front Plant Sci ; 12: 638650, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33613613

RESUMO

Plastid DNA sequence data have been traditionally widely used in plant phylogenetics because of the high copy number of plastids, their uniparental inheritance, and the blend of coding and non-coding regions with divergent substitution rates that allow the reconstruction of phylogenetic relationships at different taxonomic ranks. In the present study, we evaluate the utility of the plastome for the reconstruction of phylogenetic relationships in the pantropical plant family Ochnaceae (Malpighiales). We used the off-target sequence read fraction of a targeted sequencing study (targeting nuclear loci only) to recover more than 100 kb of the plastid genome from the majority of the more than 200 species of Ochnaceae and all but two genera using de novo and reference-based assembly strategies. Most of the recalcitrant nodes in the family's backbone were resolved by our plastome-based phylogenetic inference, corroborating the most recent classification system of Ochnaceae and findings from a phylogenomic study based on nuclear loci. Nonetheless, the phylogenetic relationships within the major clades of tribe Ochnineae, which comprise about two thirds of the family's species diversity, received mostly low support. Generally, the phylogenetic resolution was lowest at the infrageneric level. Overall there was little phylogenetic conflict compared to a recent analysis of nuclear loci. Effects of taxon sampling were invoked as the most likely reason for some of the few well-supported discords. Our study demonstrates the utility of the off-target fraction of a target enrichment study for assembling near-complete plastid genomes for a large proportion of samples.

8.
Nat Prod Res ; 35(22): 4715-4719, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31916461

RESUMO

Palicourea species has been used in folk medicine in the treatment of some diseases including cancer and inflammatory disorders. This work aimed to evaluate the in vitro antiproliferative and in vivo topical anti-inflammatory activities of the methanolic extract, fractions and two major alkaloids isolated from Palicourea minutiflora. Methanolic extract, non-alkaloidal and alkaloidal fractions exhibited strong growth inhibition for ovarian cell lines (OVCAR-3, GI50 = 3.8 at 16.3 µg mL-1) and the vincosamide alkaloid revealed selective effect on the growth of glioma cell lines (U251, GI50 = 33.0 µg mL-1) compared with doxorubicin (DOX, GI50 = 0.42 and 0.025 µg mL-1, respectively) anticancer drug. Methanolic extract, fractions and strictosidinic acid showed significant inhibitory effect with 62.7% at 77.5% (p < 0.05) to ear edema induced by croton oil and 81% at 100% (p < 0.05) to myeloperoxidase assay compared with indomethacin (positive control) 68.4% and 91.3% (p < 0.05), respectively.


Assuntos
Alcaloides , Neoplasias Ovarianas , Rubiaceae , Alcaloides/farmacologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Edema/induzido quimicamente , Edema/tratamento farmacológico , Humanos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
9.
Inorg Chem ; 59(18): 13078-13090, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32902965

RESUMO

The new luminescent carbonyl compounds [Mn(Oxa-H)(CO)3Br] (1) and [Mn(Oxa-NMe2)(CO)3Br] (2) were synthesized and fully characterized. Complexes 1 and 2 showed CO release under blue light (λ453). Spectroscopic techniques and TD-DFT and SOC-TD-DFT calculations indicated that 1 and 2 release the Oxa-H and Oxa-NMe2 coligands in addition to the carbonyl ligands, increasing the luminescence during photoinduction.

11.
PLoS One ; 15(7): e0235561, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32634141

RESUMO

BACKGROUND: The active extravasation of contrast on CT angiography (CTA) in primary intracerebral hemorrhages (ICH) is recognized as a predictive factor for ICH expansion, unfavorable outcomes and mortality. However, few studies have been conducted on the setting of traumatic brain injury (TBI). PURPOSE: To perform a literature systematic review and meta-analysis of the association of contrast extravasation on cerebral hemorrhagic contusion expansion, neurological outcomes and mortality. DATA SOURCES: The PubMed, Cochrane Library, Medline, Scielo, VHL and IBECS databases up to September 21, 2019, were searched for eligible studies. STUDY SELECTION: A total of 505 individual titles and abstracts were identified and screened. A total of 36 were selected for full text analysis, out of which 4 fulfilled all inclusion and exclusion criteria. DATA ANALYSIS: All 4 studies yielded point estimates suggestive of higher risk for hematoma expansion with contrast extravasation and the summary RR was 5.75 (95%CI 2.74-10.47, p<0.001). Contrast extravasation was also associated with worse neurological outcomes (RR 3.25, 95%CI 2.24-4.73, p<0.001) and higher mortality (RR 2.77, 95%CI 1.03-7.47, p = 0.04). DATA SYNTHESIS: This study is a Systematic Review and Meta-Analysis revealed the extravasation of contrast is a useful imaging sign to predict hematoma expansion, worse neurological outcomes and higher mortality. LIMITATIONS: Only four articles were selected. CONCLUSIONS: The extravasation of contrast in the setting of TBI is a useful imaging sign to predict hematoma expansion, worse neurological outcomes and higher mortality.


Assuntos
Lesões Encefálicas Traumáticas/patologia , Hemorragia Cerebral/diagnóstico , Extravasamento de Materiais Terapêuticos e Diagnósticos/mortalidade , Lesões Encefálicas Traumáticas/complicações , Hemorragia Cerebral/etiologia , Hemorragia Cerebral/mortalidade , Angiografia por Tomografia Computadorizada , Extravasamento de Materiais Terapêuticos e Diagnósticos/diagnóstico por imagem , Mortalidade Hospitalar , Humanos , Risco , Sensibilidade e Especificidade
12.
Biodivers Data J ; 8: e50837, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508509

RESUMO

BACKGROUND: Brazil is one of the most biodiverse countries in the world, with about 37,000 species of land plants. Part of this biodiversity is within protected areas. The development of online databases in the last years greatly improved the available biodiversity data. However, the existing databases do not provide information about the protected areas in which individual plant species occur. The lack of such information is a crucial gap for conservation actions. This study aimed to show how the information captured from online databases, cleaned by a protocol and verified by taxonomists allowed us to obtain a comprehensive list of the vascular plant species from the "Parque Nacional do Itatiaia", the first national park founded in Brazil. All existing records in the online database JABOT (15,100 vouchers) were downloaded, resulting in 11,783 vouchers identified at the species level. Overall, we documented 2,316 species belonging to 176 families and 837 genera of vascular plants in the "Parque Nacional do Itatiaia". Considering the whole vascular flora, 2,238 species are native and 78 are non-native. NEW INFORMATION: The "Parque Nacional do Itatiaia" houses 13% of the angiosperm and 37% of the fern species known from the Brazilian Atlantic Forest. Amongst these species, 82 have been cited as threatened, following IUCN categories (CR, EN or VU), seven are data deficient (DD) and 15 have been classified as a conservation priority, because they are only known from a single specimen collected before 1969.

13.
Acta amaz ; 50(2): 149-154, abr - jun. 2020.
Artigo em Inglês | LILACS | ID: biblio-1118395

RESUMO

Although the number of recently described Tovomita species is relatively high, much more remains to be done, given that each new survey of representative Amazonian collections reveals many potentially undescribed taxa. In the treatment for Tovomita published in Flora of the Venezuelan Guayana, at least six distinct morphotypes did not match any previously described species. Here we recognize morphotype "D" as a new endemic species from Cerro de la Neblina. Additionally, we provide an identification key to the Tovomita species in Venezuela. (AU)


Assuntos
Ecossistema Amazônico , Clusiaceae , Venezuela
14.
Mol Phylogenet Evol ; 149: 106844, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32325194

RESUMO

Several centers of endemism have been proposed for Melastomataceae, particularly in Amazonia and Atlantic Forest. Despite the high degree of human-caused degradation in the last 500 years, the Atlantic Forest still presents some of the largest levels of diversity and endemism across all angiosperms. With several recently described species in the last decade, the knowledge on Bertolonia's distribution and morphological characterization has changed, with most new species found in northern Atlantic Forest and with different flower color patterns than the species from southern Atlantic Forest. We first tested the monophyly of the genus sampling over 85% of its species to generate a reliable phylogenetic hypothesis. Afterwards, we used Bertolonia as a model group to study distribution patterns and morphological evolution of lineages in the Atlantic Forest. Bertolonia is particularly interesting to address such questions because it is endemic to this domain, with species distributed either in the southern, central or northern portions of the Atlantic Forest. The second step of our work aimed to respond (1) Do closely related species endemic to Atlantic Forest tend to have similar distributions and share similar morphological traits? and (2) Are floral traits more conserved within clades than vegetative characters? We hypothesize that both (1) and (2) are true due to the low dispersal ability and consequent microendemic distribution of most species in the genus. Our results confirm the veracity of the proposed hypotheses. Three major groups were recovered in our analysis: marmorata, formosa and nymphaeifolia clades. Most species that occur in northern Atlantic Forest were recovered in the marmorata clade. Most species distributed in central Atlantic Forest were recovered in the formosa clade, and the ones from the southern Atlantic Forest in the nymphaeifolia clade. A similar pattern was recovered with reproductive characters reconstructed across the phylogeny. Generally, species with pink petals and cream-colored anthers with an extrorse pore occur in northern Atlantic Forest, and species with white petals and yellow anthers with an introrse or apical pore tend to occur in southern Atlantic Forest. Some vegetative characters also have evolutionary congruence and are restricted to one or few lineages, while other characters, such as the texture of the leaf blade surface, have a strong taxonomic value and are useful to identify species, but are not homologous. Our analysis also indicates that the division between southern and northern Atlantic Forest could also be related to ancient events, not only linked with recent phylogeographic patterns. Moreover, we suggest that the orientation of the anther pore in Bertolonia could be related with diversity of species and stability of its populations. In summary, we corroborate, based on the evolutionary history of Bertolonia, that closely related species endemic to Atlantic Forest tend to have similar distributions and share similar morphological floral traits.


Assuntos
Flores/anatomia & histologia , Florestas , Melastomataceae/anatomia & histologia , Melastomataceae/classificação , Filogenia , Teorema de Bayes , Biodiversidade , Brasil , Fenótipo , Filogeografia , Pigmentação/genética
15.
Doc Ophthalmol ; 140(2): 103-113, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31571070

RESUMO

PURPOSE: To investigate the effect of different hydrophilic and rigid gas-permeable contact lens (CL) materials on multifocal electroretinography (mfERG). METHODS: The mfERG was recorded in 18 healthy subjects with RETI-port/scan21™: 11 subjects underwent mfERG recording wearing two different hydrophilic CLs with different water contents in a randomized order (1 silicone hydrogel-Comfilcon A, 48%EWC, and 1 hydrogel-Omafilcon A, 62% EWC) and 7 other subjects wore a hydrophobic rigid gas-permeable scleral lens (SL)-Hexafocon A. Control measures were recorded without CL in both groups. mfERG recordings were performed with a stimulus array pattern of 103-scaled hexagons displayed on a 19-inch RGB monitor at 28 cm distance at a frame rate of 60 Hz. The amplitude (nV), implicit time and response density (nV/deg2) of the first-order kernel components N1, P1 and N2 were evaluated for the total mfERG response and for the response averages of 4 quadrants and of 6 successive concentric rings. Subjects were optically corrected for the working distance of ERG display. RESULTS: Hydrophobic material significantly decreased the P1 amplitude of the total mfERG response, at Rings 3, 4 and 6 and Quadrant 4 (> 53.77 ± 43.2 nV; P ≤ 0.050), as well as the total (- 71.59 ± 50.68 nV) and Ring 6 (- 104.76 ± 79.88 nV) N2 amplitude (P ≤ 0.043). N1, P1 and N2 peak times suffered significant changes with both hydrophilic CL (P ≤ 0.050). Omafilcon A significantly increased P1 amplitude of Ring 5 and N2 amplitude of Ring 4, when compared to baseline (52.40 ± 71.87 nV; P = 0.036) and to Comfilcon A (39.51 ± 48.63 nV; P = 0.023), respectively. CONCLUSIONS: Hydrophobic CL slightly attenuated the strength of the mfERG signal, especially at the middle to peripheral retinal areas, while hydrophilic CL slightly changed the implicit time of the response. Different hydrophilic CL materials might affect the mfERG response differently. When considering the measurement of mfERG obtained with a CL in place, researchers should bear in mind that some changes can be related to CL material.


Assuntos
Lentes de Contato Hidrofílicas , Lentes de Contato , Hidrogéis , Retina/fisiologia , Silicones , Adulto , Eletrorretinografia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Biodivers Data J ; 8: e59664, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33424242

RESUMO

BACKGROUND: Brazilian protected areas are essential for plant conservation in the Atlantic Forest domain, one of the 36 global biodiversity hotspots. A major challenge for improving conservation actions is to know the plant richness, protected by these areas. Online databases offer an accessible way to build plant species lists and to provide relevant information about biodiversity. A list of land plants of "Parque Nacional do Caparaó" (PNC) was previously built using online databases and published on the website "Catálogo de Plantas das Unidades de Conservação do Brasil." Here, we provide and discuss additional information about plant species richness, endemism and conservation in the PNC that could not be included in the List. We documented 1,791 species of land plants as occurring in PNC, of which 63 are cited as threatened (CR, EN or VU) by the Brazilian National Red List, seven as data deficient (DD) and five as priorities for conservation. Fifity-one species were possible new ocurrences for ES and MG states. NEW INFORMATION: "Parque Nacional do Caparaó" houses 8% of the land plant species endemic to the Brazilian Atlantic Forest, including 6% of its angiosperms, 31% of its lycophytes and ferns and 14% of its avascular plants. Twelve percent of the threatened species listed for the State of Espírito Santo and 7% listed for the State of Minas Gerais are also protected by PNC. Surprisingly, 79% of the collections analysed here were carried out in Minas Gerais, which represents just 21% of the total extension of the Park. The compiled data uncover a huge botanical collection gap in this federally-protected area.

17.
PLoS One ; 14(9): e0222561, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31527912

RESUMO

The stereotyped floral morphology of Neotropical Malpighiaceae species-zygomorphic and calyx with oil glands-is correlated with oil-bee pollination. In contrast, the floral trends of the Paleotropical lineages are actinomorphy and lack of calyx glands, probably due to the absence of oil-collecting bees. The Paleotropical genus Acridocarpus is an exception because of its zygomorphic, gland-bearing flowers. Glands throughout Acridocarpus inflorescences were morphoanatomically evaluated to verify the occurrence of patterns related to species and geographic distribution. Herbarium (25 species) and fresh samples of A. longifolius were processed according to standard anatomical techniques. To verify the presence of glucose and protein, strip tests were applied to the exudate. Fresh samples were fixed and submitted to histochemical tests. Based on the occurrence, number and placement of glands, three distribution patterns were recognized on the bracteole and ten on the calyx. Bract, bracteole and sepal glands have a typical nectary structure with a palisade-like epidermis and vascularized parenchyma. Glands were classified as short-stalked, sessile or immersed. Histochemical tests performed on bract and sepal glands of A. longifolius were positive for proteins, polysaccharides and phenolic compounds, and negative for oil compounds. Glucose and protein were detected in the exudate. These results allow us to recognize the glands in Acridocarpus inflorescences as nectaries. This comprehensive morphoanatomical study helps to clarify the correlation between patterns of floral morphology and secretion consumers, as well as to better understand floral evolution in Malpighiaceae across their dispersal events.


Assuntos
Flores/anatomia & histologia , Malpighiaceae/anatomia & histologia , Animais , Abelhas , Evolução Biológica , Néctar de Plantas/análise , Polinização/fisiologia
18.
Am J Bot ; 106(9): 1156-1172, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31517989

RESUMO

PREMISE: Laticifers have evolved multiple times in angiosperms and have been interpreted as a key innovation involved in plant defense mechanisms. In Malpighiaceae, laticifers were previously known from a single lineage of trees and shrubs, the Galphimia clade, but with detailed anatomical analyses here, we show that their distribution is broader in the family, also encompassing large clades of lianas. METHODS: From 15 genera, 70 species of Malpighiaceae were surveyed through careful anatomical ontogenetic analysis of roots, stems, and leaves and detailed histochemical tests to elucidate the nature of laticifers and latex in the family. RESULTS: Articulated anastomosing laticifers were encountered in roots, stems, and leaves of two distantly related megadiverse genera of Malpighiaceae lianas: Stigmaphyllon (stigmaphylloid clade) and Tetrapterys s.s. (tetrapteroid clade). From the apex downward, in Stigmaphyllon the laticifers are derived from the procambium and from the cambium during its early activity and are present in the outermost part of the vascular cylinder of stems and leaves and in the pericycle of roots, whereas in Tetrapterys s.s. they are derived from the ground meristem, procambium, and cambium throughout the plant body and are present in the cortex and pith, either the pericycle in roots or the outermost part of the vascular system in stems and leaves, and the primary and secondary phloem. CONCLUSIONS: Laticifers seem to have evolved at least three times independently in Malpighiaceae, once in a lineage of trees and shrubs and twice in two distantly related megadiverse lianescent lineages. Laticifer evolution in Malpighiaceae is homoplastic and may be related to increases in species diversification.


Assuntos
Malpighiaceae , Látex , Meristema , Filogenia , Folhas de Planta
19.
Dalton Trans ; 48(17): 5574-5584, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30941385

RESUMO

Three new manganese carbonyl compounds with heavy atom donors were synthesized and their potential use as photoCORMS was evaluated. Interestingly, all compounds had an elusive binding mode, in which the ligands adopted a κ2-X coordination (where X = S or Se), confirmed both by X-ray crystallography and IR spectroscopy. The stability of the title compounds in the dark was determined by monitoring the changes in the UV spectra of the compounds in both dichloromethane and acetonitrile. These studies show that in coordinating solvents there is an exchange of the bromide bonded to the metal centre by a solvent molecule, which is evidenced by the changes in the UV and IR spectra and by DFT analysis. EDA and natural bond order analyses were conducted to evaluate the influence of the heavy atom donors in the first coordination sphere of the compounds. Photoexcitation at 380 nm demonstrated that all compounds showed release of all three COs, as seen in the photoproducts detected by IR spectroscopy. Furthermore, CO release was observed when the photoCORMs were incubated with living cells, and we observed a CO-dependent inhibition of cell viability.

20.
Mol Phylogenet Evol ; 134: 142-151, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30743062

RESUMO

Clusieae is an exclusively Neotropical tribe in the family Clusiaceae sensu stricto. Although tribes within Clusiaceae are morphologically and phylogenetically well-delimited, resolution among genera within these tribes remains elusive. The tribe Clusieae includes an estimated ∼500 species distributed among five genera: Chrysochlamys, Clusia, Dystovomita, Tovomita, and Tovomitopsis. In this study, we used nearly complete plastid genomes from 30 exemplar Clusieae species representing all genera recognized, plus two outgroups to infer the phylogeny of the tribe using Maximum Likelihood and Bayesian Inference. For comparison, we also inferred a phylogeny from the nuclear Internal Transcribed Spacer (ITS) region using the same methods. Our study corroborates earlier findings that Clusia is monophyletic while Tovomita is not. It also provides additional support to the hypothesis that Chrysochlamys and Tovomitopsis are not closely related despite gross morphological similarity. Tovomita is divided into three distantly related clades: (i) core Tovomita (including the type T. guianensis), (ii) T. croatii, and (iii) the T. weddelliana species complex. Members of the T. weddelliana complex are isolated from the core Tovomita, and placed in a well-supported clade that is sister to a clade composed of Chrysochlamys plus Clusia. Tovomita croatii is nested within Chrysochlamys. We propose taxonomic revisions to accommodate our phylogenetic findings, including the description of the new genus Arawakia, which includes the 18 species formerly recognized in the T. weddelliana species complex. Lectotypes are also designated for nine species (i.e., Arawakia angustata, A. lanceolata, A. lingulata, A. longicuneata, A. macrocarpa, A. oblanceolata, A. pithecobia, A. rhizophoroides, and A. weddelliana), and a taxonomic key for the identification of the six genera of Clusieae recognized is presented.


Assuntos
Clusiaceae/genética , Genomas de Plastídeos , Teorema de Bayes , Clusiaceae/anatomia & histologia , Flores/anatomia & histologia , Frutas/anatomia & histologia , Funções Verossimilhança , Filogenia
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