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1.
Food Chem ; 308: 125601, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31670190

RESUMO

The aim of this work was to analyse the hypotensive effect of amaranth protein/peptides on spontaneously hypertensive rats (SHR). The mechanism of action of these peptides was studied in vivo and ex vivo. We also tested the effect of protection against gastrointestinal digestion (GID) exerted by an O:W emulsion on the integrity of the antihypertensive peptides. All samples tested produced a decrease in blood pressure (SBP). The animals treated with emulsion (GE) and emulsion + peptide (GE+VIKP) showed the most significant reduction in the SBP (42 ±â€¯2 mmHg and 35 ±â€¯2 mmHg, respectively). The results presented suggest that after GID, a variety of peptides with biological activities were released or were resistant to this process. These peptides play a role in the regulation of the SBP by acting on plasma ACE, plasma renin and the vascular system. These results support the use of amaranth protein/peptides in the elaboration of functional foods for hypertensive individuals.


Assuntos
Amaranthus/química , Anti-Hipertensivos/farmacologia , Hipertensão/tratamento farmacológico , Peptídeos/farmacologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Animais , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Masculino , Peptídeos/uso terapêutico , Proteínas de Plantas/farmacologia , Proteínas de Plantas/uso terapêutico , Ratos , Ratos Endogâmicos SHR
2.
Front Plant Sci ; 10: 303, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30949188

RESUMO

Late Neogene and Quaternary climatic oscillations have greatly shaped the genetic structure of the Mediterranean Basin flora, with mountain plant species tracking warm interglacials/cold glacials by means of altitudinal shifts instead of broad latitudinal ones. Such dynamics may have enhanced population divergence but also secondary contacts. In this paper, we use a case example of subsection Willkommia of Centaurea (comprising three narrowly distributed endemic species, Centaurea gadorensis, C. pulvinata, and C. sagredoi) to test for reticulate evolution and recurrent hybridizations between nearby populations. For this, we combine analyses of genetic diversity and structuring, gene flow and spatial correlation, and ecological niche modeling. Our results support the contention that the current genetic structure of the three species is the result of historical gene flow at sites of secondary contact during the glacial periods, followed by isolation after the retraction of populations to the middle-upper areas of the mountains during the interglacial periods. The extent and direction of the gene flow was determined largely by the location of the populations on mountainsides oriented toward the same valley or toward different valleys, suggesting the intermountain valleys as the areas where secondary contacts occurred.

3.
J Exp Bot ; 69(5): 983-996, 2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29190388

RESUMO

Pollen wall exine is usually deposited non-uniformly on the pollen surface, with areas of low exine deposition corresponding to pollen apertures. Little is known about how apertures form, with the novel Arabidopsis INP1 (INAPERTURATE POLLEN1) protein currently being the only identified aperture factor. In developing pollen, INP1 localizes to three plasma membrane domains and underlies formation of three apertures. Although INP1 homologs are found across angiosperms, they lack strong sequence conservation. Thus, it has been unclear whether they also act as aperture factors and whether their sequence divergence contributes to interspecies differences in aperture patterns. To explore the functional conservation of INP1 homologs, we used mutant analysis in maize and tested whether homologs from several other species could function in Arabidopsis. Our data suggest that the INP1 involvement in aperture formation is evolutionarily conserved, despite the significant divergence of INP1 sequences and aperture patterns, but that additional species-specific factors are likely to be required to guide INP1 and to provide information for aperture patterning. To determine the regions in INP1 necessary for its localization and function, we used fragment fusions, domain swaps, and interspecific protein chimeras. We demonstrate that the central portion of the protein is particularly important for mediating the species-specific functionality.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Pólen/crescimento & desenvolvimento , Sequência de Aminoácidos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Evolução Biológica , Pólen/genética , Pólen/metabolismo , Alinhamento de Sequência , Especificidade da Espécie
4.
Behav Pharmacol ; 28(7): 582-585, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28704275

RESUMO

Major depression is one of the most common affective disorders caused by schizophrenia. The administration of N-methyl-D-aspartate receptor antagonists, such as ketamine, can reproduce the negative and affective symptoms of this disorder in animals. Preclinical studies have shown that 5-HT6 receptor (5-HT6R) agonists and antagonists have a considerable antipsychotic response. The aim of the present study was to evaluate the effect of an acute treatment with an agonist, E-6837, and an antagonist, SB-271046, of 5-HT6R on the immobility induced in mice by a subchronic ketamine regimen (5 days; 10 mg/kg/day, intraperitoneal). Repeated ketamine administration alone increased the immobility time in the forced-swimming test and the tail-suspension test. E-6837 at 10 and 20 mg/kg caused a significant reduction of immobility in the tail-suspension test and forced-swimming test, respectively. Interestingly, SB-271046 (10 mg/kg) also elicited an antidepressant-like effect in both tests. The current findings suggest an important role for these 5-HT6R ligands as mood modulators. However, it is necessary to explore the physiological mechanisms involved in this process in greater detail.


Assuntos
Indóis/farmacologia , Receptores de Serotonina/metabolismo , Sulfonamidas/farmacologia , Tiofenos/farmacologia , Animais , Antidepressivos/farmacologia , Antipsicóticos/farmacologia , Depressão/tratamento farmacológico , Transtorno Depressivo Maior/tratamento farmacológico , Modelos Animais de Doenças , Elevação dos Membros Posteriores/métodos , Ketamina/farmacologia , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Esquizofrenia/tratamento farmacológico , Natação/fisiologia
5.
Rev. colomb. cardiol ; 24(3): 298-298, mayo-jun. 2017. graf
Artigo em Espanhol | LILACS-Express | ID: biblio-900531

RESUMO

Resumen La enfermedad de Erdheim-Chester es una histiocitosis celular diferente a la histiocitosis de Langerhans, de origen incierto. Se caracteriza por una implicación multi-orgánica debida a la infiltración de los histiocitos CD68+/CD1a-, en forma de xantogranulomas, que afectan principal y comúnmente a la metáfisis y diáfisis de huesos largos. El diagnóstico se realiza mediante biopsia, donde se revelan histiocitos CD68+/CD1a-, carencia de proteína S, y presencia de gránulos de Birbeck. Se ha subestimado la implicación cardiovascular. Reportamos un caso de un varón de 67 años con la enfermedad de Erdheim-Chester e infarto de miocardio agudo, debido a implicación coronaria, además de enfermedad ósea, vascular, pituitaria y retroperitoneal. Revisamos la literatura relevante y describimos el tratamiento clínico de estos pacientes.


Abstract Erdheim-Chester disease is a non-Langerhans cell histiocytosis of uncertain origin. It is characterized by multiorgan involvement due to infiltration of CD68+/CD1a- histiocytes, in the form of xantogranulomas, most commonly affecting the metaphysis and diaphysis of long bones. The diagnosis is made by biopsy showing CD68+/CD1ahistiocytes, lack of S protein and Birbeck granules. Cardiovascular involvement is underestimated. We report a case of a 67 year-old man with Erdheim-Chester disease and acute myocardial infarction due to coronary involvement, in addition to bone, vascular, pituitary and retroperitoneal disease. We review relevant literature and describe the clinical management of these patients.

6.
Clín. investig. arterioscler. (Ed. impr.) ; 29(2): 98-102, mar.-abr. 2017. ilus
Artigo em Espanhol | IBECS | ID: ibc-161021

RESUMO

La lipoproteína (a) [Lp(a)] es una lipoproteína definida por presentar una apolipoproteína específica, la apoA, unida a la apoB-100 por diversos tipos de enlaces químicos, entre ellos un puente disulfuro. A pesar de que su mecanismo aterogénico no es completamente conocido, está demostrada su importancia en el desarrollo de ateroesclerosis prematura, mostrando múltiples estudios su papel como factor de riesgo cardiovascular asociado a enfermedad coronaria e ictus. Presentamos el caso de una paciente con diagnóstico de arteritis de Takayasu en la que se detectó una elevación masiva de Lp(a), y abordamos las implicaciones diagnósticas y terapéuticas que tuvo este hallazgo


Lipoprotein (a) [Lp(a)] is a lipoprotein defined by presenting a specific apolipoprotein, ApoA, linked to the ApoB-100 by different types of chemical bonds, including a disulfide bridge. Despite their atherogenic mechanism is not fully understood, its importance has been demonstrated in the development of premature aterosclerosis. Multiple studies have shown its role as a cardiovascular risk factor associated with heart disease and stroke. We report the case of a patient with a diagnosis of Takayasu arteritis in which a massive elevation of Lp(a) was detected. We emphasize its diagnostic and therapeutic implications


Assuntos
Humanos , Feminino , Adulto , Arterite de Takayasu/complicações , Hiperlipoproteinemias/complicações , Arteriosclerose/diagnóstico , Diagnóstico Diferencial , Hipertensão/complicações
7.
Clin Investig Arterioscler ; 29(2): 98-102, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28188021

RESUMO

Lipoprotein (a) [Lp(a)] is a lipoprotein defined by presenting a specific apolipoprotein, ApoA, linked to the ApoB-100 by different types of chemical bonds, including a disulfide bridge. Despite their atherogenic mechanism is not fully understood, its importance has been demonstrated in the development of premature aterosclerosis. Multiple studies have shown its role as a cardiovascular risk factor associated with heart disease and stroke. We report the case of a patient with a diagnosis of Takayasu arteritis in which a massive elevation of Lp(a) was detected. We emphasize its diagnostic and therapeutic implications.


Assuntos
Aterosclerose/patologia , Lipoproteína(a)/sangue , Arterite de Takayasu/patologia , Adulto , Aterosclerose/sangue , Aterosclerose/diagnóstico , Doenças Cardiovasculares/etiologia , Angiografia por Tomografia Computadorizada , Feminino , Humanos , Fatores de Risco , Arterite de Takayasu/sangue , Arterite de Takayasu/diagnóstico
8.
Int J Pharm ; 517(1-2): 50-57, 2017 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-27915007

RESUMO

Quercetin has been identified as a promising compound with a neuroprotective potential against age-related neurodegenerative diseases such as Alzheimer's disease (AD). Nevertheless, the clinical application of quercetin is hampered by its low oral bioavailability. The aim of this work was to evaluate the capability of nanoencapsulated quercetin in zein nanoparticles (NPQ), that significantly improves the oral absorption and bioavailability of the flavonoid, as potential oral treatment for AD. For this purpose, SAMP8 mice were orally treated for two months with either NPQ (25mg/kg every 48h) or a solution of quercetin (Q; 25mg/kg daily). NPQ displayed a size of 260nm and a payload of about 70µg/mg. For Q, no significant effects were observed in animals. On the contrary, the oral administration of NPQ improved the cognition and memory impairments characteristics of SAMP8 mice. These observations appeared to be related with a decreased expression of the hippocampal astrocyte marker GFAP. Furthermore, significant levels of quercetin were quantified in the brain of mice treated with nanoparticles. These findings highlight the potential of zein nanoparticles to promote the oral absorption of quercetin as well as the therapeutic potential of this flavonoid in AD pathogenesis.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Comportamento Animal/efeitos dos fármacos , Portadores de Fármacos/química , Atividade Motora/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Quercetina/uso terapêutico , 2-Hidroxipropil-beta-Ciclodextrina , Administração Oral , Doença de Alzheimer/psicologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Modelos Animais de Doenças , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos Endogâmicos , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/farmacocinética , Tamanho da Partícula , Quercetina/administração & dosagem , Quercetina/farmacocinética , Teste de Desempenho do Rota-Rod , Zeína/química , beta-Ciclodextrinas/química
9.
J Plant Res ; 129(6): 1085-1096, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27590132

RESUMO

Studies of pollen wall development produce a great deal of morphological data that supplies useful information regarding taxonomy and systematics. We present the exine development of Euptelea and Pteridophyllum, two taxa whose pollen wall development has never previously been studied using transmission electron microscopy. Both genera are representatives of the two earliest-diverging families of the order Ranunculales and their pollen data are important for the diagnosis of the ancestral pollen features in eudicots. Our observations show these genera are defined by having microechinate microreticulate exine ornamentation, perforate tectum, columellate morphology of the infratectum and the existence of a foot layer and endexine. The presence of lamellations is detected during the early stages of development in the nexine of both genera, especially in the apertures. Euptelea presents remains of the primexine layer during the whole maturation process, a very thin foot layer, and a laminate exinous oncus in the apertural region formed by ectexine and endexine elements. Pteridophyllum has a thicker tectum than Euptelea, a continuous foot layer and a thicker endexine. In the apertures, the exinous oncus is formed by islets and granules of endexine, in contrast to the Euptelea apertures. The secretory tapetum produces orbicules in both genera, but they have different morphology and electron-density. Comparisons with pollen data from related orders and families confirm the ancestral states for the pollen of eudicots proposed in previous studies: reticulate and echinate surfaces, columellate infractectum and a thin foot layer relative to the thickness of the ectexine. According to our observations, we propose considering the possibility of a polymorphic state for the aperture number in the ancestor of Ranunculales, and suggest the development of orbicules as the ancestral state in this order.


Assuntos
Evolução Biológica , Magnoliopsida/crescimento & desenvolvimento , Pólen/crescimento & desenvolvimento , Fumariaceae/crescimento & desenvolvimento , Fumariaceae/ultraestrutura , Magnoliopsida/ultraestrutura , Microscopia Eletrônica de Transmissão , Pólen/ultraestrutura , Especificidade da Espécie
10.
Behav Pharmacol ; 27(5): 485-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27035065

RESUMO

Some types of schizophrenia have been associated with repetitive movements lacking specific purpose, also known as stereotyped behavior. Dopamine agonists (D2) and noncompetitive N-methyl-D-aspartate receptor antagonists (e.g. ketamine) have been administered in rodent models to induce stereotyped behavior that resembles some motor symptoms of schizophrenia. Recently, a relationship has been found between 5-HT6 receptors (5-HT6Rs) and dopaminergic activity. The present study evaluates the effect of ketamine (5 and 10 mg/kg), alone and in combination with the 5-HT6R agonist E-6837, on the climbing behavior of male mice. Ketamine was administered with an acute (1 day) and subchronic (5 day) scheme. Later, these doses and schemes were combined with an acute scheme of E-6837 (5 and 10 mg/kg). With both the acute and the subchronic schemes, ketamine increased climbing behavior at a dose of 10 mg/kg, and this effect was reversed by E-6837 (at 5 and 10 mg/kg). The present results suggest that there is an interaction between N-methyl-D-aspartate and 5-HT6 receptors in the regulation of climbing behavior. Further research is necessary to provide more evidence on this interaction.


Assuntos
Comportamento Animal/efeitos dos fármacos , Indóis/farmacologia , Ketamina/farmacologia , Comportamento Estereotipado/efeitos dos fármacos , Sulfonamidas/farmacologia , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Esquema de Medicação , Antagonistas de Aminoácidos Excitatórios/administração & dosagem , Antagonistas de Aminoácidos Excitatórios/farmacologia , Indóis/administração & dosagem , Ketamina/administração & dosagem , Masculino , Camundongos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de Serotonina/efeitos dos fármacos , Receptores de Serotonina/metabolismo , Esquizofrenia/tratamento farmacológico , Esquizofrenia/fisiopatologia , Agonistas do Receptor de Serotonina/administração & dosagem , Agonistas do Receptor de Serotonina/farmacologia , Sulfonamidas/administração & dosagem
12.
Med. clín (Ed. impr.) ; 146(3): 117-120, feb. 2016. tab
Artigo em Espanhol | IBECS | ID: ibc-147824

RESUMO

Fundamento y objetivo: El bexaroteno es un rexinoide sintético selectivo del receptor X aprobado para el tratamiento sistémico del linfoma cutáneo de células T. Durante el tratamiento es muy frecuente la aparición de hipotiroidismo e hiperlipidemia mixta grave, siendo ambos efectos adversos reversibles y dependientes de la dosis. La elevación del colesterol LDL y los triglicéridos (hasta unos niveles aumentados que incluso se han asociado a pancreatitis en algunos casos) está ampliamente descrita (al igual que sucede con otros retinoides), siendo el descenso del colesterol HDL menos conocido. Revisamos nuestra experiencia con el uso de bexaroteno. Material y métodos: Se presenta una serie de 3 casos de pacientes tratados con bexaroteno en los que, además de sufrir los efectos adversos bien conocidos, se observó un grave descenso del colesterol HDL. Resultados: Los 3 pacientes estudiados presentaron complicaciones metabólicas en forma de hipotiroidismo central e hiperlipidemia mixta grave, con especial énfasis en el marcado descenso que experimentaron nuestros pacientes (descenso medio > 83%) en las cifras de colesterol HDL. El tratamiento hipolipidemiante y hormonal sustitutivo con levotiroxina dio lugar a una mejoría de los parámetros, sin llegar a alcanzarse los objetivos. Conclusiones: El bexaroteno produce, como efectos secundarios predecibles, una hiperlipidemia mixta grave con descenso marcado de los niveles de colesterol HDL e hipotiroidismo central, los cuales son reversibles y dependientes de la dosis. Se incluye una reflexión sobre los posibles mecanismos etológicos e implicaciones de este fenómeno (AU)


Background and objective: Bexarotene is a synthetic selective X receptor rexinoide approved for the systemic treatment of cutaneous T-cell lymphoma. During treatment is very frequent the occurrence of hypothyroidism and severe mixed hyperlipidemia, both are reversibles and dose-dependent adverse events. Increase of triglycerides and LDL-cholesterol level (up to even higher levels have been associated with pancreatitis in some cases) is widely described (as is the case with other retinoids) but decrease in HDL-cholesterol is poored know. We review our experience with the use of bexarotene. Material and methods: We present a serie of 3 clinical report of patients treated with bexarotene in whose, in addition to these well-known adverse event, a serious lowering of HDL-cholesterol was observed. Results: The 3 patients studied had metabolic complications like central hypothyroidism and severe mixed hyperlipidemia; with special emphasis on the sharp fall (mean decrease > 83%) in the HDL-cholesterol level. Cholesterol lowering medication and substitutive hormonal replacement with levotiroxine resulted in an improvement of the biochimical parameters without reaching the correct goals. Conclusions: Bexarotene produce as predictable side effects severe mixed hyperlipidemia with marked decrease in HDL-cholesterol levels and central hypothyroidism, being the both reversible and dose-dependent. A reflection on the possible aetiological mechanisms and implications of this phenomenon are included (AU)


Assuntos
Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Idoso , Linfoma Cutâneo de Células T/complicações , Linfoma Cutâneo de Células T/diagnóstico , Tetra-Hidronaftalenos/efeitos adversos , Tetra-Hidronaftalenos/uso terapêutico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/complicações , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , HDL-Colesterol , Tiroxina/uso terapêutico , Hipotireoidismo/induzido quimicamente , Hipotireoidismo/complicações , Hiperlipidemias/induzido quimicamente , Hiperlipidemias/complicações , Testes de Função Tireóidea/tendências
14.
Med Clin (Barc) ; 146(3): 117-20, 2016 Feb 05.
Artigo em Espanhol | MEDLINE | ID: mdl-26688184

RESUMO

BACKGROUND AND OBJECTIVE: Bexarotene is a synthetic selective X receptor rexinoide approved for the systemic treatment of cutaneous T-cell lymphoma. During treatment is very frequent the occurrence of hypothyroidism and severe mixed hyperlipidemia, both are reversibles and dose-dependent adverse events. Increase of triglycerides and LDL-cholesterol level (up to even higher levels have been associated with pancreatitis in some cases) is widely described (as is the case with other retinoids) but decrease in HDL-cholesterol is poored know. We review our experience with the use of bexarotene. MATERIAL AND METHODS: We present a serie of 3 clinical report of patients treated with bexarotene in whose, in addition to these well-known adverse event, a serious lowering of HDL-cholesterol was observed. RESULTS: The 3 patients studied had metabolic complications like central hypothyroidism and severe mixed hyperlipidemia; with special emphasis on the sharp fall (mean decrease>83%) in the HDL-cholesterol level. Cholesterol lowering medication and substitutive hormonal replacement with levotiroxine resulted in an improvement of the biochimical parameters without reaching the correct goals. CONCLUSIONS: Bexarotene produce as predictable side effects severe mixed hyperlipidemia with marked decrease in HDL-cholesterol levels and central hypothyroidism, being the both reversible and dose-dependent. A reflection on the possible aetiological mechanisms and implications of this phenomenon are included.


Assuntos
Antineoplásicos/efeitos adversos , Hiperlipidemias/induzido quimicamente , Hipotireoidismo/induzido quimicamente , Micose Fungoide/tratamento farmacológico , Síndrome de Sézary/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Tetra-Hidronaftalenos/efeitos adversos , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bexaroteno , HDL-Colesterol/sangue , Terapia Combinada , Humanos , Hiperlipidemias/sangue , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Hipotireoidismo/sangue , Hipotireoidismo/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Transplante de Células-Tronco de Sangue Periférico , Radioterapia Adjuvante , Terapia de Salvação , Neoplasias Cutâneas/radioterapia , Neoplasias Cutâneas/terapia , Tetra-Hidronaftalenos/administração & dosagem , Tiroxina/uso terapêutico
15.
Appl Plant Sci ; 3(11)2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26649267

RESUMO

PREMISE OF THE STUDY: We characterize 10 microsatellite loci in the endangered fern Vandenboschia speciosa (Hymenophyllaceae), enabling studies on the genetic population structure of this Macaronesian-European species using DNA hypervariable markers. METHODS AND RESULTS: Ten primer sets were developed and tested on 47 individuals in a total of two Iberian populations of V. speciosa. The primers amplified di- and hexanucelotide repeats. The number of alleles ranged from two to eight, and the expected heterozygosity ranged from 0.107 to 0.807 among the populations analyzed. CONCLUSIONS: The 10 microsatellite markers developed will be useful in characterizing the genetic diversity of V. speciosa and understanding its population structure (including the possible structure between sporophyte and gametophyte phases) and biogeographic history, and will provide important genetic data for the conservation of this species.

16.
Mol Phylogenet Evol ; 88: 75-92, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25862377

RESUMO

Fumitories (subfamily Fumarioideae, Papaveraceae) represent, by their wide mainly northern temperate distribution (also present in South Africa) a suitable plant group to use as a model system for studying biogeographical links between floristic regions of the Northern Hemisphere and also the Southern Hemisphere Cape region. However, the phylogeny of the entire Fumarioideae subfamily is not totally known. In this work, we infer a molecular phylogeny of Fumarioideae, which we use to interpret the biogeographical patterns in the subfamily and to establish biogeographical links between floristic regions, such as those suggested by its different inter- and intra-continental disjunctions. The tribe Hypecoeae is the sister group of tribe Fumarieae, this latter holding a basal grade of monotypic or few-species genera with bisymmetric flowers, and a core group, Core Fumarieae, of more specious rich genera with zygomorphic flowers. The biogeographical analysis shows a subfamily that originated in East Asia at the end of the Early Cretaceous. From here, ancestral range expansions followed three different directions, one at the beginning of the Late Cretaceous by the ancestor of tribe Hypecoeae towards central Asia, and two during the Cretaceous-Palaeogene transition towards western North America and Indochina by the ancestor of the tribe Fumarieae. The ancestor of Core Fumarieae expanded its range from East Asia into the Himalayas before to the middle Eocene. The uplifts of the Qinghai-Tibetan Plateau together with the zonal climate pattern of the Palaeogene are suggested to be responsible both for the accelerated diversification rate resulting in the origin of the basal lineages of Core Fumarieae as well as for the westward migration of the ancestor of Fumarieae s.str. into the Irano-Turanian region. From here, this latter group reached South Africa during late Eocene and Mediterranean basin during Oligocene. There were two colonization waves of the Mediterranean following two different routes: a northern route during the early Oligocene by the subtribe Sarcocapninae, probably facilitated by the land bridge resulting of the Mediterranean microplate accretion; and a southern route into North Africa, through the Gomphotherium land bridge, taken by the subtribe Fumariinae between late Oligocene and middle Miocene.


Assuntos
Papaveraceae/classificação , Filogenia , Evolução Biológica , Clima , Fenômenos Geológicos , Papaveraceae/genética , Filogeografia
17.
Psiquiatr. biol. (Internet) ; 22(1): 5-11, ene.-abr. 2015. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-136572

RESUMO

Diversos antagonistas del receptor N-metil-D-aspartato (RNMDA) como la fenciclidina o la ketamina estudiados en roedores han permitido inducir alteraciones cognitivas similares a las observadas en la esquizofrenia. Casualmente, uno de los receptores a serotonina, el 5-HT6, ha cobrado interés en la búsqueda de nuevos fármacos con propiedades procognitivas. Con la finalidad de comprender mejor la interacción de ambos receptores (NMDA y 5-HT6) en la regulación cognitiva se realizó una revisión exhaustiva en la literatura. Varios estudios con esquemas agudos o subcrónicos de los antagonistas NMDA en roedores fueron evaluados en distintas pruebas, en donde se encontró deterioro cognitivo. Fue común que el esquema agudo de diversos fármacos serotoninérgicos 5-HT6 revirtiera el deterioro cognitivo inducido por la administración previa de los antagonistas del RNMDA. Por el contrario y sorprendentemente, la inyección aguda y combinada tanto de los antagonistas NMDA como de los fármacos serotoninérgicos 5-HT6 lograron fortalecer la memoria. El esquema subcrónico de los antagonistas NMDA representa el modelo más integrador para el estudio de las alteraciones cognitivas asociadas a la esquizofrenia. Aunque el deterioro y el efecto procognitivo mediados por estos receptores pudieran ser explicados mediante la regulación conjunta que ejercen ambos receptores sobre la liberación de distintos neurotransmisores como el glutamato, es una situación compleja que se requiere continuar investigando para fundamentar mejor estas ideas (AU)


Diverse antagonists of the NMDA receptor studied in rodents, such as phencyclidine or ketamine, have enabled researchers to induce cognitive changes similar to those found in schizophrenia. Interestingly, one of the serotonin receptors, 5-HT6, has attracted much attention for the development of new drugs with pro-cognitive properties. With the aim of better understanding the interaction of both NMDA and 5-HT6 in cognitive regulation, an exhaustive review of the literature was carried out. Various studies have found cognitive impairment, evaluated in rodents using different tests, after applying acute or sub-chronic schemes of NMDA antagonists. An acute scheme of applying different serotogenic 5-HT6 receptors has often reversed the cognitive impairment induced by the previous administration of NMDA antagonists. Surprisingly, an acute injection of a combination of suboptimal doses of NMDA and 5-HT6 antagonists resulted in strengthening memory. The sub-chronic scheme of NMDA antagonists represents the most reliable model for the study of cognitive changes associated with schizophrenia. Cognitive impairment, as well as a pro-cognitive effect mediated by NMDA and 5-HT6, may be explained by a joint regulation of these receptors to modulate the release of distinct neurotransmitters, such as glutamate. This represents a complex interaction that requires ongoing research to clarify the mechanisms at play (AU)


Assuntos
Animais , Masculino , Feminino , Camundongos , Ratos , N-Metilaspartato/administração & dosagem , N-Metilaspartato/efeitos adversos , N-Metilaspartato/análise , Receptores de N-Metil-D-Aspartato/uso terapêutico , Esquizofrenia/diagnóstico , Esquizofrenia/terapia , Glutamatos/uso terapêutico , Serotonina/uso terapêutico , Ketamina/uso terapêutico , Disfunção Cognitiva/complicações , Disfunção Cognitiva/psicologia , Terapia Cognitivo-Comportamental/métodos , Terapia Cognitivo-Comportamental/tendências , Modelos Animais , Psiquiatria Biológica/métodos , Psiquiatria Biológica/tendências
18.
New Phytol ; 206(3): 1172-83, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25557021

RESUMO

Tragopogon includes two classic examples of recently formed allopolyploid species in North America: T. mirus and T. miscellus. Older Tragopogon allotetraploids from Eurasia offer ideal taxa for comparing the longer term outcomes of allopolyploidy. To help resolve the ancestry of one of these older polyploids, phylogenetic analyses of multiple populations of the allotetraploid T. castellanus (2n = 24) and its putative diploid parents, T. crocifolius and T. lamottei, were conducted using sequences from nuclear (internal transcribed spacer, ITS; and alcohol dehydrogenase 1A, Adh) and plastid (trnT-trnL spacer, trnL intron, trnL-trnF spacer and rpl16 intron) loci. Fluorescence in situ hybridization (FISH) and genomic in situ hybridization (GISH) were used to investigate the chromosomal constitution of T. castellanus. Our data confirm that the widely distributed T. crocifolius and the Iberian endemic, T. lamottei, are the diploid parents of T. castellanus, and that this polyploid formed at least three times. One group of populations of T. castellanus is distinct in exhibiting two pairs of rearranged chromosomes. These data suggest that some of the chromosomal variants that originate in young polyploids (here, an intergenomic translocation) may become fixed in populations, contributing to novelty in older polyploid lineages. The geographical distributions of the allopolyploids and parents are also complex, with allotetraploid populations being disjunct from one or both of the most closely related diploid parental populations.


Assuntos
Asteraceae/genética , Cromossomos de Plantas , Filogenia , Tetraploidia , Asteraceae/fisiologia , Evolução Biológica , Ecossistema , Hibridização In Situ , Cariotipagem , Dados de Sequência Molecular , Espanha
19.
J Plant Res ; 127(5): 575-83, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25030895

RESUMO

In a previous work, we characterized the HinfI satellite DNA family in the subtribe Centaureinae (Cardueae) demonstrating that a "library" of eight HinfI subfamilies would exist in the common ancestor of all Centaureinae, which were differentially amplified in different lineages. Now, we extend our study by analyzing a total of 219 additional repeats from fifteen species belonging to Carlininae, Echinopsinae and Carduinae, and comparing them to those of Centaureinae. Most HinfI sequences belonged to the subfamily II, although a few sequences of other subfamilies were detected in some species. Additionally, a new subfamily characteristic of several Carduinae species was discovered. Although phylogenetic trees grouped sequences by subfamily affinity instead of species provenance, when comparing repeats of the same subfamily, the degree of divergence between any pair of sequences was related to the evolutionary distance between the species compared in most cases. Exceptions were in comparisons between sequences of some Centaureinae species, and between sequences of some Carduinae species and those of Centaureinae. Our results demonstrate that: (1) At least nine HinfI subfamilies would exist in the common ancestor of Cardueae, each one differentially amplified in different lineages; (2) After differential spreading, sequences of each subfamily evolved concertedly through molecular drive, resulting in the gradual divergence of repeats between different species; (3) The rate to which concerted evolution occurred was different between lineages according to the evolutionary history of each one.


Assuntos
Asteraceae/genética , Evolução Biológica , DNA de Plantas/genética , DNA Satélite/genética , Família Multigênica , Sequências Repetitivas de Ácido Nucleico/genética
20.
Mol Phylogenet Evol ; 77: 195-215, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24784974

RESUMO

The Centaurea group is part of the Circum-Mediterranean Clade (CMC) of genus Centaurea subgenus Centaurea, a mainly Mediterranean plant group with more than 200 described species. The group is traditionally split on morphological basis into three sections: Centaurea, Phalolepis and Willkommia. This division, however, is doubtful, especially in light of molecular approaches. In this study we try to resolve this phylogenetic problem and to consolidate the circumscription and delimitation of the entire group against other closely related groups. We analyzed nuclear (internal transcribed spacer of the ribosomal genes) and chloroplast (rpl32-trnL intergenic spacer) DNA regions for most of the described species of the Centaurea group using phylogenetic and network approaches, and we checked the data for recombination. Phylogeny was used to reconstruct the evolution of the lacerate-membranaceous bract appendages using parsimony. The magnitude of incomplete lineage sorting was tested estimating the effective population sizes. Molecular dating was performed using a Bayesian approach, and the ancestral area reconstruction was conducted using the Dispersal-Extinction-Cladogenesis method. Monophyly of the Centaurea group is confirmed if a few species are removed. Our results do not support the traditional sectional division. There is a high incongruence between the two markers and between genetic data and morphology. However, there is a clear relation between geography and the structure of the molecular data. Diversification in the Centaurea group mainly took place during the Pliocene and Pleistocene. The ancestral area infered for the Circum-Mediterranean Clade of Centaurea is the Eastern Mediterranean, whereas for the Centaurea group it is most likely NW-Africa. The large incongruencies, which hamper phylogenetic reconstruction, are probably the result of introgression, even though the presence of incomplete lineage sorting as an additional factor cannot be ruled out. Convergent evolution of morphological traits may have led to incongruence between morphology-based, traditional systematics and molecular results. Our results also cast major doubts about current species delimitation.


Assuntos
Centaurea/genética , Filogenia , África , Teorema de Bayes , Centaurea/anatomia & histologia , DNA de Plantas/genética , Especiação Genética , Filogeografia , Recombinação Genética , Análise de Sequência de DNA
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