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1.
Mol Phylogenet Evol ; 142: 106659, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639525

RESUMO

A major goal of phylogenetic systematics is to understand both the patterns of diversification and the processes by which these patterns are formed. Few studies have focused on the ancient, species-rich Magnoliales clade and its diversification pattern. Within Magnoliales, the pantropically distributed Annonaceae are by far the most genus-rich and species-rich family-level clade, with c. 110 genera and c. 2,400 species. We investigated the diversification patterns across Annonaceae and identified traits that show varied associations with diversification rates using a time-calibrated phylogeny of 835 species (34.6% sampling) and 11,211 aligned bases from eight regions of the plastid genome (rbcL, matK, ndhF, psbA-trnH, trnL-F, atpB-rbcL, trnS-G, and ycf1). Twelve rate shifts were identified using BAMM: in Annona, Artabotrys, Asimina, Drepananthus, Duguetia, Goniothalamus, Guatteria, Uvaria, Xylopia, the tribes Miliuseae and Malmeeae, and the Desmos-Dasymaschalon-Friesodielsia-Monanthotaxis clade. TurboMEDUSA and method-of-moments estimator analyses showed largely congruent results. A positive relationship between species richness and diversification rate is revealed using PGLS. Our results show that the high species richness in Annonaceae is likely the result of recent increased diversification rather than the steady accumulation of species via the 'museum model'. We further explore the possible role of selected traits (habit, pollinator trapping, floral sex expression, pollen dispersal unit, anther septation, and seed dispersal unit) in shaping diversification patterns, based on inferences of BiSSE, MuSSE, HiSSE, and FiSSE analyses. Our results suggest that the liana habit, the presence of circadian pollinator trapping, androdioecy, and the dispersal of seeds as single-seeded monocarp fragments are closely correlated with higher diversification rates; pollen aggregation and anther septation, in contrast, are associated with lower diversification rates.


Assuntos
Annonaceae/classificação , Annonaceae/genética , Biodiversidade , Genoma de Planta , Filogenia , Plastídeos/genética
2.
J Pharm Sci ; 73(9): 1290-3, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6491953

RESUMO

An ion-pairing liquid chromatographic method with UV detection is described for the determination of minoxidil in bulk drug, compressed tablet, and topical solution formulations. The chromatographic system consists of a microparticulate octadecylsilica column and a mobile phase composed of sodium dioctylsulfosuccinate in aqueous methanol (pH 3). The bulk drug and the topical solution samples are prepared by the dissolution of the drug in internal standard solution. Sample preparation for the compressed tablet formulation involves dissolving the drug from an aliquot of pulverized sample and centrifuging to remove insoluble excipients. Quantitative recovery of minoxidil from formulation excipients was demonstrated; assay precision was less than 1% CV.


Assuntos
Minoxidil/análise , Pirimidinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Concentração de Íons de Hidrogênio , Soluções , Comprimidos
4.
Mol Ecol Resour ; 9(3): 864-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-21564771

RESUMO

The bluntnose minnow (Pimephales notatus) is abundant and widespread with a broad ecological niche. This species is also sexually dimorphic with strong competition between males during the mating season. We developed two genomic libraries enriched for microsatellite repeats - one dinucleotide and one tetranucleotide - and isolated 48 putative, novel microsatellite loci. Of those, we present 35 polymorphic and statistically independent microsatellite markers with two to 18 alleles per locus and heterozygosities ranging from 0.04 to 1. These markers will be useful for future behavioural, ecological, evolutionary and mating system studies using P. notatus.

5.
Mol Ecol Resour ; 9(1): 251-4, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21564618

RESUMO

The central stoneroller (Campostoma anomalum) is an abundant, widespread and sexually dimorphic stream minnow that is a useful model for mating system studies as well as a sentinel species for understanding population-level processes for fishes in headwater communities. We developed one genomic library enriched for dinucleotide repeats and isolated 48 putative, novel microsatellite loci. Of those, we present 32 polymorphic and independent microsatellite markers with 3 to 16 alleles per locus and heterozygosity ranging from 0.23 to 0.95. Hence, these markers will be useful for future behavioural, ecological and evolutionary studies using C. anomalum.

6.
Mol Ecol Resour ; 8(6): 1483-5, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21586083

RESUMO

The genus Etheostoma is a species-rich and ecologically important group of fishes in North America. The orangethroat darter (Etheostoma spectabile) is widely distributed and abundant in headwater streams throughout the central Midwest, and is an excellent model for ecological and mating system studies. We developed 23 novel, polymorphic, and independent microsatellite loci for E. spectabile. We found from two to 14 alleles per locus, and observed heterozygosities ranged from 0.39 to 1.0. These markers, in combination with others isolated from Etheostoma taxa, will be useful for ecological and evolutionary studies in the genus.

7.
Clin Chem ; 24(10): 1690-9, 1978 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29720

RESUMO

We report the kinetics of the reactions of unconjugated bilirubin and conjugated bilirubin with p-diazobenzene sulfonic acid in aqueous media. Our studies confirm that each reaction proceeds in two steps and that the second step is catalyzed by sulfanilic acid. In the presence of an excess of p-diazobenzenesulfonic acid and in the absence of sulfanilic acid, the reaction for either unconjugated or conjugated bilirubin proceeds in two successive first-order steps, the second step being much the slower. This study emphasizes the first step in the reaction for each species and includes data on the effects of p-diazobenzenesulfonic acid, albumin, benzoate, and caffeine concentrations, pH in the range from 4 to 12, and temperature. Mechanisms proposed for reactions with and without caffeine are used to develop rate equations, and the kinetic data are used to evaluate rate constants, acid dissociation constants for the different bilirubin species, and formation constants for bilirubin-caffeine complex species that are proposed.


Assuntos
Compostos Azo , Benzenossulfonatos , Bilirrubina , Bilirrubina/análogos & derivados , Cafeína , Fenômenos Químicos , Química , Compostos de Diazônio , Concentração de Íons de Hidrogênio , Cinética , Albumina Sérica , Espectrofotometria , Ácidos Sulfanílicos
8.
Clin Chem ; 24(10): 1700-7, 1978 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29721

RESUMO

This paper describes a fast kinetic method for the simultaneous determination of unconjugated and conjugated bilirugin in the same reaction solution. A stopped-flow mixing system with a stabilized photometer and small computer is used to mix sample and reagent rapidly and to record 250 data points during a 700-ms reaction time, and a regression program is used to resolve these kinetic data into the concentrations of unconjugated and conjugated bilirubin. Data are reported for synthetic single and two-component samples and for serum samples. Kinetic results for synthetic mixtures and serum samples are compared with results obtained by a conventional two-step procedure. Regression equations show good linearity between kinetically determined absorbance changes and concentration, good agreement between taken and found values for total, unconjugated, and conjugated bilirubin for synthetic samples in human serum albumin, and a good correlation between kinetic and equilibrium results for these species in sera. Regression slopes for kinetic vs. equilibrium assay results for total, unconjugated, and conjugated bilirubins in sera were 1.01 +/- 0.05, 1.04 +/- 0.03 and 0.91 +/- 0.04, respectively, with intercepts of 6.6,--2.7, and 3.8 micromol/liter, and standard errors of estimate of 28, 14, and 20 micromol/liter. These data reflect uncertainties in both the kinetic and equilibrium methods.


Assuntos
Bilirrubina/análogos & derivados , Bilirrubina/análise , Bilirrubina/sangue , Humanos , Concentração de Íons de Hidrogênio , Cinética , Modelos Químicos , Espectrofotometria
9.
J Chromatogr ; 316: 461-72, 1984 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-6530422

RESUMO

A detector for liquid chromatography based on light-scattering was evaluated to determine its application to pharmaceutical analysis. It performed adequately as a mass detector in liquid-solid chromatography of steroids, since response factors were equal to within 20%. The detection limit was approximately 0.5 micrograms. In reversed-phase chromatography response factors varied from 0.13 to 1.0 because of partial vaporization of some steroids. Stable baselines were obtained in gradient elution chromatography, but response varied with solvent composition. This detector was useful for determining impurities in bulk pharmaceuticals.


Assuntos
Esteroides/análise , Cromatografia Líquida/métodos , Luz , Tamanho da Partícula , Espalhamento de Radiação , Temperatura
10.
J Chromatogr ; 202(1): 99-106, 1980 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-7217248

RESUMO

A reversed-phase ion-pairing high-performance liquid chromatographic procedure with refractive index or UV 214 nm detection was developed for the separation of clindamycin, clindamycin B, and 7-epiclindamycin. The chromatographic retention behavior of these compounds on an octadecylsilane column was investigated as a function of pairing-ion, mobile phase composition, and pH. The method was applied to the determination of clindamycin in bulk drug and in a number of pharmaceutical formulations. The relative standard deviations for all assays was in the 0.5-2% range.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Clindamicina/isolamento & purificação
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