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1.
Am J Bot ; 104(11): 1717-1728, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29170248

RESUMO

PREMISE OF THE STUDY: American amphitropical disjunction (AAD) is an important but understudied New World biogeographic pattern in which related plants occur in extratropical North America and South America, but are absent in the intervening tropics. Subtribe Amsinckiinae (Boraginaceae) is one of the richest groups of plants displaying the AAD pattern. Here, we infer a time-calibrated molecular phylogeny of the group to evaluate the number, timing, and directionality of AAD events, which yields generalizable insights into the mechanism of AAD. METHODS: We perform a phylogenomic analysis of 139 samples of subtribe Amsinckiinae and infer divergence times using two calibration schemes: with only fossil calibrations and with fossils plus a secondary calibration from a recent family level analysis. Biogeographic analysis was performed in the R package BioGeoBEARS. KEY RESULTS: We document 18 examples of AAD in the Amsinckiinae. Inferred divergence times of these AAD examples were strongly asynchronous, ranging from Miocene (17.1 million years ago [Ma]) to Pleistocene (0.33 Ma), with most (12) occurring <5 Ma. Four events occurred 10-5 Ma, during the second rise of the Andes. All AAD examples had a North America to South America directionality. CONCLUSIONS: Second only to the hyperdiverse Poaceae in number of documented AAD examples, the Amsinckiinae is an ideal system for the study of AAD. Asynchronous divergence times support the hypothesis of long-distance dispersal by birds as the mechanism of AAD in the subtribe and more generally. Further comparative phylogenomic studies may permit biogeographic hypothesis testing and examination of the relationship between AAD and fruit morphology, reproductive biology, and ploidy.


Assuntos
Boraginaceae/genética , Dispersão Vegetal , Animais , Aves , Boraginaceae/fisiologia , Fósseis , América do Norte , Filogenia , Filogeografia , América do Sul
2.
PhytoKeys ; 197: 149-164, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36760673

RESUMO

In an earlier molecular phylogenetic study, a sample of what was originally identified as Cryptanthahispida (Boraginaceae) from Chile, grouped with species of the genus Johnstonella. This sample was subsequently shown not to be C.hispida, but an undescribed species, endemic to the dry Puna of Chile. This new species is described here as Johnstonellapunensis, along with a key to all South American species of the genus. Johnstonellapunensis resembles other members of that genus in having an ovate fruit shape, ovate nutlets and a long style that extends beyond the nutlets. It is unusual in the genus in having a non-tuberculate, dimpled to rugulose nutlet surface sculpturing. Its closest relative within the genus is likely the South American J.diplotricha.


ResumenEn un estudio filogenético molecular anterior, una muestra que originalmente se identificó como Cryptanthahispida (Boraginaceae) de Chile se agrupaba con especies del género Johnstonella. Posteriormente se demostró que esta muestra no era C.hispida sino una especie no descrita, endémica de la Puna seca de Chile. Esta nueva especie se describe aquí como Johnstonellapunensis, junto con una clave para todas las especies sudamericanas del género. Johnstonellapunensis se parece a otros miembros del género por tener un fruto de forma ovadа, clusas ovadas y un estilo largo que sobrepasa las clusas. Es inusual en el género que la clusa tenga una superficie no tuberculada, sino que rugulosa formando hoyuelos. Su pariente más cercano dentro del género es probablemente la especie sudamericana J.diplotricha.

3.
PhytoKeys ; 181: 29-47, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34557054

RESUMO

During the preparation of the treatment of the genus Cryptantha Lehmann ex G. Don for South America, numerous names were identified as needing typification to stabilize their nomenclature. As a result, lectotypes are designated for 11 names and second-step lectotypes for 20 names. Furthermore, supporting information about the type material of the basionyms of four Cryptantha names already typified by Johnston (Eritrichiumtalquinum Phil., Eritrichiumdimorphum Phil., Eritrichiumcarrizalense Phil., and Eritrichiumsubamplexicaule Phil.) is provided.

4.
Neurosci Lett ; 357(3): 232-4, 2004 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-15003292

RESUMO

Immunocytochemistry was used to demonstrate the presence of beta-endorphin and alpha-MSH, and in situ hybridisation was used to study the presence of pro-opiomelanocortin (POMC) mRNA, in spinal motoneurones, up to 8 days following the administration of a single dose of acrylamide in mice. The proportions of POMC-mRNA positive neurones, beta-endorphin-immunoreactive neurones and alpha-MSH-immunoreactive neurones were significantly increased in the treated animals compared to controls. It seems likely that upregulation of the POMC gene precedes acrylamide-induced neuropathy.


Assuntos
Acrilamida/administração & dosagem , Regulação da Expressão Gênica/efeitos dos fármacos , Neurônios Motores/efeitos dos fármacos , Pró-Opiomelanocortina/metabolismo , Acrilamida/farmacologia , Animais , Contagem de Células/métodos , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Masculino , Camundongos , Neurônios Motores/metabolismo , Pró-Opiomelanocortina/genética , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Medula Espinal/citologia , Medula Espinal/efeitos dos fármacos , Fatores de Tempo , Regulação para Cima , alfa-MSH/metabolismo , beta-Endorfina/metabolismo
5.
Mar Environ Res ; 54(3-5): 543-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12408614

RESUMO

The Mersey estuary is the most contaminated estuary in British waters. Detailed studies are underway on the pathology of flounder (Platichthys flesus) from the Mersey and on flounder from the nearby, but less contaminated, Dee estuary. Flounder breed offshore but spend a lot of time in the estuaries, penetrating into freshwater. These flatfish are in close contact with sediments and will be exposed to exenobiotic stored in the sediments. Plaice (Pleuronectes platessa) are flatfish which enter the Mersey with the tidal flow but spend less time in the estuary than flounder and are less likely to show evidence of pollutant exposure. Over 20 plaice were collected from the Mersey. Samples of the liver, kidney and gonad were fixed in 10% formal saline, processed into paraffin wax and 5 microm sections cut and stained with haematoxylin and eosin. Liver changes consisted of variable amounts of glycogen/lipid storage product, minor perivenular and perivascular fibrosis, and helminth parasitisation. No tumours or foci of cellular alteration, necrosis and inflammation were seen. In the gonad only changes consistent with normal gonadal cycling was seen. These studies provide evidence that plaice show little or no evidence of toxic pathological damage resulting from their stay in the estuary.


Assuntos
Exposição Ambiental , Linguado , Gônadas/patologia , Rim/patologia , Fígado/patologia , Poluentes Químicos da Água/efeitos adversos , Animais , Inglaterra , Feminino , Gônadas/química , Rim/química , Fígado/química , Cirrose Hepática/etiologia , Cirrose Hepática/veterinária , Masculino
6.
Appl Plant Sci ; 2(12)2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25506521

RESUMO

PREMISE OF THE STUDY: As systematists grapple with how to best harness the power of next-generation sequencing (NGS), a deluge of review papers, methods, and analytical tools make choosing the right method difficult. Oreocarya (Boraginaceae), a genus of 63 species, is a good example of a group lacking both species-level resolution and genomic resources. The use of Geneious removes bioinformatic barriers and makes NGS genome skimming accessible to even the least tech-savvy systematists. • METHODS: A combination of de novo and reference-guided assemblies was used to process 100-bp single-end Illumina HiSeq 2000 reads. A subset of 25 taxa was used to test the suitability of genome skimming for future systematic studies in recalcitrant lineages like Oreocarya. • RESULTS: The nuclear ribosomal cistron, the plastome, and 12 mitochondrial genes were recovered from all 25 taxa. All data processing and phylogenomic analyses were performed in Geneious. We report possible future multiplexing levels and published low-copy nuclear genes represented within de novo contigs. • DISCUSSION: Genome skimming represents a much-improved primary data collection over PCR+Sanger sequencing when chloroplast DNA (cpDNA), nuclear ribosomal DNA (nrDNA), and mitochondrial DNA (mtDNA) are the target sequences. This study details methods that plant systematists can employ to study their own taxa of interest.

7.
Ecotoxicol Environ Saf ; 58(3): 324-34, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15223258

RESUMO

Three different physiological parameters were assessed to determine their potential for serving as biomarkers to predict abnormally elevated vitellogenin (VTG) production in male and immature flounder. Whereas abnormally elevated mean VTG plasma concentrations clearly distinguished the Mersey and Dee flounder studied, the results showed no significant differences in estrogen receptor binding capacity or binding affinity between the two groups. Hepatocyte proliferation was not found to be a "biomarker of effect" that could specifically be used to assess an increase in VTG-related proliferation. Nevertheless, immunohistochemical staining for proliferating cell nuclear antigen did show a significantly higher proliferative activity in the livers of Mersey flounder than that in Dee flounder. Sperm motility also was not found to be a biomarker of effect linked to an abnormal elevation of VTG plasma concentration. The results (higher sperm quality in terms of motility in Mersey flounder) were unexpected but interesting.


Assuntos
Estrogênios/toxicidade , Linguado/metabolismo , Hepatócitos/efeitos dos fármacos , Receptores de Estrogênio/metabolismo , Vitelogeninas/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/análise , Biomarcadores/sangue , Divisão Celular/efeitos dos fármacos , Exposição Ambiental , Monitoramento Ambiental , Feminino , Linguado/sangue , Hepatócitos/química , Hepatócitos/metabolismo , Masculino , Receptores de Estrogênio/análise , Água do Mar , Motilidade dos Espermatozoides/efeitos dos fármacos , Fatores de Tempo , Reino Unido , Vitelogeninas/sangue , Xenobióticos/toxicidade
8.
Ecotoxicol Environ Saf ; 58(3): 356-64, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15223260

RESUMO

Vitellogenin (VTG) plasma concentrations were measured in flounder (Platicthys flesus L.) caught in two neighbouring UK estuaries between autumn 1997 and summer 2000. As found in previous studies, male and immature female flounder that were caught in the Mersey, but not in the Dee, had abnormally elevated concentrations of VTG in their plasma-evidence of the presence of natural and synthetic estrogens and/or xenoestrogens in the Mersey. The present study reveals a marked seasonal cycle in VTG concentrations in males. In late spring and summer, male flounder in the Mersey have relatively low concentrations of VTG (microg mL(-1) range). However, in mid-winter, mean concentrations were as high as 5 mg mL(-1). There is also evidence that there was a lessening in the degree of estrogenic endocrine disruption between 1996-1997 (the period of the initial studies on the Mersey) and 1998-2000 (the period covered by the present study). Only 0.5% of the fish contained ovotestes (intersex condition).


Assuntos
Estrogênios não Esteroides/toxicidade , Linguado/metabolismo , Vitelogeninas/sangue , Poluentes Químicos da Água/toxicidade , Xenobióticos/toxicidade , Fatores Etários , Animais , Biomarcadores/sangue , Transtornos do Desenvolvimento Sexual/induzido quimicamente , Exposição Ambiental , Monitoramento Ambiental , Feminino , Linguado/anormalidades , Linguado/sangue , Masculino , Estações do Ano , Água do Mar , Fatores Sexuais , Fatores de Tempo , Reino Unido
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