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1.
Mycologia ; 116(3): 418-430, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38530332

RESUMO

In 1895 and 2001, rust fungi affecting Licania trees (Chrysobalanchaceae) in Brazil were described as Uredo licaniae by Hennings in the state of Goiás and as Phakopsora tomentosae by Ferreira et al. in the state of Amazonas, respectively. Recently, a Licania rust fungus collected close to the Amazonian type location sharing symptoms with the former two species was subjected to morphological examinations and molecular phylogenetic analyses using 28S nuc rDNA (ITS2-28S) and cytochrome c oxidase subunit III (CO3) gene sequences. Since the original type specimen of Ph. tomentosae is considered lost, we carefully reviewed the type description and questioned the identity of the telium, which justified the description of the fungus as a Phakopsora species. Furthermore, the additional revision of the type material described by Hennings revealed that Ph. tomentosae is a synonym of U. licaniae. Based on the morphological examinations, disease symptoms, and shared hosts, we concluded that the newly collected material is conspecific with U. licaniae. However, the phylogenetic analyses rejected allocation in Phakopsora and instead assigned the Licania rust fungus in a sister relationship with Austropuccinia psidii (Sphaerophragmiaceae), the causal agent of the globally invasive myrtle rust pathogen. We therefore favored a recombination of U. licaniae (syn. Ph. tomentosae) into Austropuccinia and proposed the new name Austropuccina licaniae for the second species now identified for this genus. The fungus shares conspicuous symptoms with A. psidii, causing often severe infections of growing leaves and shoots that lead to leaf necrosis, leaf shedding, and eventually to the dieback of entire shoots. In view of the very similar symptoms of its aggressively invasive sister species, we briefly discuss the current state of knowledge about A. licaniae and the potential risks, and the opportunity of its identification.


Assuntos
Basidiomycota , DNA Fúngico , Filogenia , Doenças das Plantas , Basidiomycota/genética , Basidiomycota/classificação , Basidiomycota/isolamento & purificação , Doenças das Plantas/microbiologia , DNA Fúngico/genética , Brasil , Análise de Sequência de DNA , RNA Ribossômico 28S/genética , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Árvores/microbiologia
2.
Mycologia ; 115(6): 802-812, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37862601

RESUMO

Two Cerrado rust fungi, Phakopsora rossmaniae and Aplopsora hennenii, described in 1993 and 1995 and originally assigned to families Phakopsoraceae and Ochropsoraceae, respectively, were subjected to molecular phylogenetic analyses using fragments of the nuc 28S and 18S rDNA and mitochondrial cytochrome c oxidase subunit 3 (CO3) gene. Although both taxa were morphologically well placed in their original genera, they were shown to belong in a strongly supported new lineage within the Raveneliineae distant from the Phakopsoraceae and Ochropsoraceae. Therefore, we properly treated this lineage as the new genus Cerradopsora now harboring C. rossmaniae (type species) and C. hennenii. However, this novel phakopsoroid genus remains in uncertain familial position without support to be included in any of the families that share space within the Raveneliineae.


Assuntos
Basidiomycota , Humanos , Filogenia , DNA Fúngico/genética , Basidiomycota/genética , DNA Ribossômico/genética
3.
Mycologia ; 115(2): 263-276, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36912901

RESUMO

The multicellular discoid convex teliospore heads represent a prominent generic feature of the genus Ravenelia. However, recent molecular phylogenetic work has shown that this is a convergent trait, and that this genus does not represent a natural group. In 2000, a rust fungus infecting the Caesalpinioid species Cenostigma macrophyllum (= C. gardnerianum) was described as Ravenelia cenostigmatis. This species shows some rare features, such as an extra layer of sterile cells between the cysts and the fertile teliospores, spirally ornamented urediniospores, as well as strongly incurved paraphyses giving the telia and uredinia a basket-like appearance. Using freshly collected specimens of Rav. cenostigmatis and Rav. spiralis on C. macrophyllum, our phylogenetic analyses based on the nuc 28S, nuc 18S, and mt CO3 (cytochrome c oxidase subunit 3) gene sequences demonstrated that these two rust fungi belong in a lineage within the Raveneliineae that is distinct from Ravenelia s. str. Besides proposing their recombination into the new genus Raveneliopsis (type species R. cenostigmatis) and briefly discussing their potentially close phylogenetic affiliations, we suggest that five other Ravenelia species that are morphologically and ecologically close to the type species of Raveneliopsis, i.e., Rav. corbula, Rav. corbuloides, Rav. parahybana, Rav. pileolarioides, and Rav. Striatiformis, may be recombined pending new collections and confirmation through molecular phylogenetic analyses.


Assuntos
Basidiomycota , Fabaceae , Brasil , Filogenia , Basidiomycota/genética
4.
Mycologia ; 114(5): 868-886, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35913839

RESUMO

The genus Cerradoa (type species Cerradoa palmaea) was established in 1978 by Hennen and Ono and named after the Brazilian Cerrado biome. The holotype collected in Planaltina, Federal District, Brazil, belonged to the first rust fungus reported on palms (Arecaceae). For decades, the status of Cerradoa as a distinct genus has been regarded as doubtful, representing a synonym of Edythea (Uropyxidaceae) starting with the second edition of the Illustrated Genera of Rust Fungi in 1983. Our molecular phylogenetic analyses, as well as our morphological investigations, allowed us to reject this synonymy, leading to the reinstatement of Cerradoa within the Pucciniaceae. Cerradoa, together with morphologically similar genera such as the newly established Pseudocerradoa with two species (Ps. paullula and Ps. rhaphidophorae) infecting araceous hosts, the fern rust Desmella, and also P. engleriana, could not be assigned to any of the seven identified major lineages within the Pucciniaceae. Edythea, instead of being maintained as a member of the Uropyxidaceae, was herein placed in Pucciniaceae, shown phylogenetically in close relationship to Cumminsiella mirabilissima, both infecting the Berberidaceae. Additionally, our extensive phylogenetic analyses add guidance for future taxonomic revisions in the highly polyphyletic genus Puccinia and other established taxa within the family Pucciniaceae.


Assuntos
Filogenia , Brasil
5.
Zoo Biol ; 40(4): 280-287, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33739467

RESUMO

Biological resource banks represent valuable tools for the conservation of species vulnerable to extinction, such as the jaguar. Cryobanks of skins have the potential to safeguard rare genotypes, allowing the potential exploitation of biological samples in animal multiplication technologies and the study of genetic variability. Determination of the most suitable skin regions for tissue conservation can help increase the efficiency of cryobanks and the storage of biological samples. To this end, we evaluated the effects of vitrification of skin tissues from the ear, caudal, and femoral regions of a post-mortem jaguar belonging to a zoo in Brazil. Non-vitrified and vitrified samples were evaluated and compared using quantitative methods, focusing on skin thickness, cell quantification, number of perinuclear halos, collagen and elastic density, and proliferative activity. No differences were observed in skin thickness, number of perinuclear halos, elastic density, and proliferative activity between non-vitrified and vitrified tissues in skin from any region. However, vitrified tissues derived from femoral skin showed a reduction in the number of fibroblasts, epidermal cells and collagen density compared to non-vitrified tissues. In summary, the ear and caudal regions provided the best conservation of somatic tissues derived from jaguars, and skin samples from these regions are therefore the most suitable for the formation of cryobanks.


Assuntos
Criopreservação/veterinária , Panthera/fisiologia , Fenômenos Fisiológicos da Pele , Pele/anatomia & histologia , Manejo de Espécimes , Vitrificação , Animais , Orelha , Cauda
6.
Plants (Basel) ; 8(11)2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31671821

RESUMO

Brazil and Argentina have a combined soybean area of 53.6 million hectares, which accounts for over half of the total global production. The soybean crop in South America extends from latitude 8-10° S to 32-36° S. Such a vast, almost contiguous area imposes a serious sanitary risk to the crop. Currently, the prevalence of anthracnose is increasing, with recurring reports of severe epidemics and expressive yield losses. Soybean anthracnose is mainly associated with Colletotrichum truncatum, although other Colletotrichum species have also been reported as causal agents of this disease. Knowledge about the morphological, cultural, and molecular variability of C. truncatum in South America is crucial for disease management. Here, we present data on the molecular, morphological, biological, cultural, and pathogenicity of C. truncatum isolates collected in Brazil and Argentina. Light microscopy and randomly-amplified polymorphic DNA (RAPD) analysis were used for estimating the variability of isolates. Colletotrichum truncatum displayed three types of conidiogenesis, viz. conidial formation from conidiogenous cells on hyphal extremities, in conidiomas in acervuli, and directly from fertile setae (a mechanism yet-unreported for C. truncatum). RAPD profiling was effective in revealing the genetic diversity among C. truncatum isolates. The intra-group similarity was greater among the Argentinian isolates when compared to the Brazilian group. Furthermore, the results indicated a strong correlation between geographical origin and molecular grouping, with the exclusive or semi-exclusive assembling of Brazilian and Argentinian isolates in distinct clades. Finally, a preliminary account of the reaction of soybean accessions to C. truncatum is also included.

7.
Diabetes Care ; 36(8): 2233-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23564917

RESUMO

OBJECTIVE: Medical nutrition therapy based on the control of the amount and distribution of carbohydrates (CHO) is the initial treatment for gestational diabetes mellitus (GDM), but there is a need for randomized controlled trials comparing different dietary strategies. The purpose of this study was to test the hypothesis that a low-CHO diet for the treatment of GDM would lead to a lower rate of insulin treatment with similar pregnancy outcomes compared with a control diet. RESEARCH DESIGN AND METHODS: A total of 152 women with GDM were included in this open, randomized controlled trial and assigned to follow either a diet with low-CHO content (40% of the total diet energy content as CHO) or a control diet (55% of the total diet energy content as CHO). CHO intake was assessed by 3-day food records. The main pregnancy outcomes were also assessed. RESULTS: The rate of women requiring insulin was not significantly different between the treatment groups (low CHO 54.7% vs. control 54.7%; P = 1). Daily food records confirmed a difference in the amount of CHO consumed between the groups (P = 0.0001). No differences were found in the obstetric and perinatal outcomes between the treatment groups. CONCLUSIONS: Treatment of women with GDM using a low-CHO diet did not reduce the number of women needing insulin and produced similar pregnancy outcomes. In GDM, CHO amount (40 vs. 55% of calories) did not influence insulin need or pregnancy outcomes.


Assuntos
Diabetes Gestacional/dietoterapia , Dieta com Restrição de Carboidratos , Adulto , Glicemia/metabolismo , Diabetes Gestacional/tratamento farmacológico , Feminino , Humanos , Insulina/uso terapêutico , Cetose/urina , Gravidez , Resultado da Gravidez
8.
J Pediatr Gastroenterol Nutr ; 54(1): 48-54, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21832955

RESUMO

OBJECTIVES: The aim of the study was to characterize a group of 11 pediatric patients, ages 3 to 13 years, affected by Wilson disease (WD) in the island of Gran Canaria, Spain. PATIENTS AND METHODS: Genetic, biochemical, and pathological features, together with their response to treatment and clinical evolution, have been analyzed for this group of patients. RESULTS: Genetically, the group was rather homogeneous, with an extremely high prevalence of the L708P mutation (4 homozygotes and 5 heterozygotes). Despite being initially screened because of asymptomatic hypertransaminemia, all of the patients presented with some degree of liver damage that was never accompanied by any neurological manifestation. Hepatic damage was most severe in a compound heterozygote with a novel mutation, G1266W, affecting a motif in the ATP7B polypeptide that is greatly conserved in similar proteins among metazoans. Ceruloplasmin and copper serum levels, together with the determination of hepatic copper content, were found to be of great diagnostic value, whereas urine copper measurements were found to be much less conclusive. All of the patients responded well to treatment with D-penicillamine with no documented adverse reactions. CONCLUSIONS: The patients in Gran Canaria constitute, overall, one of the largest groups of patients with WD with a high incidence of a single mutation, allowing us to define the early clinical symptoms and the evolution of the disease in patients carrying the ATP7B L708P mutant allele, and the study of WD in a genetically homogeneous background.


Assuntos
Adenosina Trifosfatases/genética , Proteínas de Transporte de Cátions/genética , Cobre/metabolismo , Degeneração Hepatolenticular/genética , Fígado/patologia , Mutação , Adolescente , Ceruloplasmina/metabolismo , Quelantes/uso terapêutico , Criança , Pré-Escolar , ATPases Transportadoras de Cobre , Progressão da Doença , Feminino , Genótipo , Degeneração Hepatolenticular/metabolismo , Degeneração Hepatolenticular/patologia , Humanos , Fígado/metabolismo , Masculino , Penicilamina/uso terapêutico
9.
Mol Ecol Resour ; 9(3): 874-6, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-21564774

RESUMO

Colossoma macropomum is a keystone species of the Amazon floodplain, and is an important but severely overexploited commercial species. To provide tools for addressing ecological and conservation questions, we developed 14 highly polymorphic microsatellite markers that had between four and 21 alleles per locus in the 25 tested individuals. With the exception of comparisons involving the locus Cm1F5 that also showed heterozygosity deficiency, no pairs of loci were at linkage disequilibrium. Many of the microsatellite loci were also variable in three other serrasalmid species which span the phylogenetic depth of the Serrasalmidae.

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