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1.
Zookeys ; 1175: 5-162, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37636532

RESUMEN

The parasitoid wasp genus Alphomelon Mason, 1981 is revised, based on a combination of basic morphology (dichotomous key and brief diagnostic descriptions), DNA barcoding, biology (host data and wasp cocoons), and distribution data. A total of 49 species is considered; the genus is almost entirely Neotropical (48 species recorded from that region), but three species reach the Nearctic, with one of them extending as far north as 45° N in Canada. Alphomelon parasitizes exclusively Hesperiinae caterpillars (Lepidoptera: Hesperiidae), mostly feeding on monocots in the families Arecaceae, Bromeliaceae, Cannaceae, Commelinaceae, Heliconiaceae, and Poaceae. Most wasp species parasitize either on one or very few (2-4) host species, usually within one or two hesperiine genera; but some species can parasitize several hosts from up to nine different hesperiine genera. Among species with available data for their cocoons, roughly half weave solitary cocoons (16) and half are gregarious (17); cocoons tend to be surrounded by a rather distinctive, coarse silk (especially in solitary species, but also distinguishable in some gregarious species). Neither morphology nor DNA barcoding alone was sufficient on its own to delimit all species properly; by integrating all available evidence (even if incomplete, as available data for every species is different) a foundation is provided for future studies incorporating more specimens, especially from South America. The following 30 new species are described: cruzi, itatiaiensis, and palomae, authored by Shimbori & Fernandez-Triana; and adrianguadamuzi, amazonas, andydeansi, calixtomoragai, carolinacanoae, christerhanssoni, diniamartinezae, duvalierbricenoi, eldaarayae, eliethcantillanoae, gloriasihezarae, guillermopereirai, hazelcambroneroae, josecortesi, keineraragoni, luciarosae, manuelriosi, mikesharkeyi, osvaldoespinozai, paramelanoscelis, paranigriceps, petronariosae, ricardocaleroi, rigoi, rostermoragai, sergioriosi, and yanayacu, authored by Fernandez-Triana & Shimbori.

2.
Gigascience ; 112022 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-35482490

RESUMEN

BACKGROUND: Traditional biomonitoring approaches have delivered a basic understanding of biodiversity, but they cannot support the large-scale assessments required to manage and protect entire ecosystems. This study used DNA metabarcoding to assess spatial and temporal variation in species richness and diversity in arthropod communities from 52 protected areas spanning 3 Canadian ecoregions. RESULTS: This study revealed the presence of 26,263 arthropod species in the 3 ecoregions and indicated that at least another 3,000-5,000 await detection. Results further demonstrate that communities are more similar within than between ecoregions, even after controlling for geographical distance. Overall α-diversity declined from east to west, reflecting a gradient in habitat disturbance. Shifts in species composition were high at every site, with turnover greater than nestedness, suggesting the presence of many transient species. CONCLUSIONS: Differences in species composition among their arthropod communities confirm that ecoregions are a useful synoptic for biogeographic patterns and for structuring conservation efforts. The present results also demonstrate that metabarcoding enables large-scale monitoring of shifts in species composition, making it possible to move beyond the biomass measurements that have been the key metric used in prior efforts to track change in arthropod communities.


Asunto(s)
Artrópodos , Ecosistema , Animales , Artrópodos/genética , Biodiversidad , Canadá , Código de Barras del ADN Taxonómico/métodos
3.
Plant Dis ; 105(6): 1666-1676, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33147122

RESUMEN

Four clades of Plasmopara viticola isolated from wild and cultivated Vitis species were described in 2013. Only P. viticola clades riparia and aestivalis have been detected in eastern Canada. To increase our understanding of the epidemiology of these clades of P. viticola, airborne sporangia were monitored with spore samplers at two experimental vineyards from 2015 to 2018 and at 11, 14, and 15 commercial vineyards in 2016, 2017, and 2018, respectively. At each vineyard and in each year, airborne sporangia were assessed three times weekly from grapevine budbreak to harvest. To accurately monitor airborne inoculum, a specific and sensitive quantitative PCR assay for simultaneous quantification of P. viticola clades riparia and aestivalis was developed. At the experimental site, in the vineyard planted with the hybrid grape variety Chancellor, mostly P. viticola clade riparia was detected. In vineyards planted with multiple grape varieties, airborne sporangia of P. viticola clade riparia were prevalent at the beginning of the season, whereas P. viticola clade aestivalis was mostly detected from midseason to harvest. At the commercial sites, airborne sporangia of P. viticola clade riparia were more prevalent in 2016, whereas P. viticola clade aestivalis was more prevalent in 2017 and 2018. The only significant difference between the inoculum progress curves was the time at which 50% of the seasonal inoculum was reached, with an average for the 3 years of 100.8 and 117.9 days since 1 May for P. viticola clade riparia and clade aestivalis, respectively. When airborne sporangium concentrations were expressed as the proportion of the two clades, in general, the proportion of clade aestivalis to that of clade riparia was low at the beginning of the season and increased to reach approximately 0.9 to 1.0 at the end of the season. These results suggest that both clades of P. viticola coexist, but that clade aestivalis is predominant and that downy mildew epidemics caused by P. viticola clade riparia occur 2 to 3 weeks before those caused by clade aestivalis.


Asunto(s)
Oomicetos , Vitis , Granjas , Oomicetos/genética , Enfermedades de las Plantas , Reacción en Cadena de la Polimerasa , Vitis/genética
4.
Am J Hypertens ; 33(3): 243-251, 2020 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-31730171

RESUMEN

BACKGROUND: Studies have shown that self-monitoring of blood pressure (BP) is effective when combined with co-interventions, but its efficacy varies in the presence of some co-morbidities. This study examined whether self-monitoring can reduce clinic BP in patients with hypertension-related co-morbidity. METHODS: A systematic review was conducted of articles published in Medline, Embase, and the Cochrane Library up to January 2018. Randomized controlled trials of self-monitoring of BP were selected and individual patient data (IPD) were requested. Contributing studies were prospectively categorized by whether they examined a low/high-intensity co-intervention. Change in BP and likelihood of uncontrolled BP at 12 months were examined according to number and type of hypertension-related co-morbidity in a one-stage IPD meta-analysis. RESULTS: A total of 22 trials were eligible, 16 of which were able to provide IPD for the primary outcome, including 6,522 (89%) participants with follow-up data. Self-monitoring was associated with reduced clinic systolic BP compared to usual care at 12-month follow-up, regardless of the number of hypertension-related co-morbidities (-3.12 mm Hg, [95% confidence intervals -4.78, -1.46 mm Hg]; P value for interaction with number of morbidities = 0.260). Intense interventions were more effective than low-intensity interventions in patients with obesity (P < 0.001 for all outcomes), and possibly stroke (P < 0.004 for BP control outcome only), but this effect was not observed in patients with coronary heart disease, diabetes, or chronic kidney disease. CONCLUSIONS: Self-monitoring lowers BP regardless of the number of hypertension-related co-morbidities, but may only be effective in conditions such obesity or stroke when combined with high-intensity co-interventions.


Asunto(s)
Monitoreo Ambulatorio de la Presión Arterial , Presión Sanguínea , Hipertensión/diagnóstico , Hipertensión/terapia , Autocuidado , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Hipertensión/epidemiología , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Multimorbilidad , Valor Predictivo de las Pruebas , Pronóstico , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Factores de Tiempo
5.
Mol Ecol Resour ; 16(3): 809-22, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26602739

RESUMEN

DNA sequences offer powerful tools for describing the members and interactions of natural communities. In this study, we establish the to-date most comprehensive library of DNA barcodes for a terrestrial site, including all known macroscopic animals and vascular plants of an intensively studied area of the High Arctic, the Zackenberg Valley in Northeast Greenland. To demonstrate its utility, we apply the library to identify nearly 20 000 arthropod individuals from two Malaise traps, each operated for two summers. Drawing on this material, we estimate the coverage of previous morphology-based species inventories, derive a snapshot of faunal turnover in space and time and describe the abundance and phenology of species in the rapidly changing arctic environment. Overall, 403 terrestrial animal and 160 vascular plant species were recorded by morphology-based techniques. DNA barcodes (CO1) offered high resolution in discriminating among the local animal taxa, with 92% of morphologically distinguishable taxa assigned to unique Barcode Index Numbers (BINs) and 93% to monophyletic clusters. For vascular plants, resolution was lower, with 54% of species forming monophyletic clusters based on barcode regions rbcLa and ITS2. Malaise catches revealed 122 BINs not detected by previous sampling and DNA barcoding. The insect community was dominated by a few highly abundant taxa. Even closely related taxa differed in phenology, emphasizing the need for species-level resolution when describing ongoing shifts in arctic communities and ecosystems. The DNA barcode library now established for Zackenberg offers new scope for such explorations, and for the detailed dissection of interspecific interactions throughout the community.


Asunto(s)
Biota , Código de Barras del ADN Taxonómico/métodos , Ecosistema , Animales , Regiones Árticas , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Complejo IV de Transporte de Electrones/genética , Groenlandia , Filogenia , Plantas , Ribulosa-Bifosfato Carboxilasa/genética
6.
Transfus Clin Biol ; 22(3): 107-11, 2015 Aug.
Artículo en Francés | MEDLINE | ID: mdl-26049675

RESUMEN

Red blood cell units are stored up to 42 days post-collection. The standard policy of blood banks is to deliver the oldest units in order to limit blood wastage. Many caregivers believe that giving fresh rather than old units can improve the outcome of their transfused patients. The ABLE study aims to check if the transfusion of red blood cell units stored seven days or less (fresh arm) improve the outcome of transfused critically ill adults compared to patients who received units delivered according to the standard delivery policy (control arm). From March 2009 to May 2014, 1211 patients were allocated to the fresh arm, 1219 to the control arm (length of storage: 6.1 ± 4.9 and 22.0 ± 8.4 days respectively, P<0.001). The primary outcome measure was 90-day all-cause mortality post-randomisation: there were 448 deaths (37.0%) in the fresh arm and 430 (35.3%) in the control arm (absolute risk difference: 1.7%; 95% confidence interval: -2.1% to 5.5%). In a survival analysis, the risk of death was higher in the fresh arm (hazard ratio: 1.1; 95%CI: 0.9 to 1.2), but the difference was not statistically significant (P=0.38). The same trend against the fresh arm was observed with all but one secondary outcome measures. The conclusion is that the transfusion of red blood cell units stored seven days or less does not improve the outcome of critically ill adults compared to the transfusion of units stored about three weeks (22.0 ± 8.4 days).


Asunto(s)
Conservación de la Sangre/métodos , Enfermedad Crítica/terapia , Envejecimiento Eritrocítico , Transfusión de Eritrocitos , Adulto , Canadá/epidemiología , Cuidados Críticos/métodos , Enfermedad Crítica/mortalidad , Grupos Diagnósticos Relacionados , Europa (Continente)/epidemiología , Femenino , Mortalidad Hospitalaria , Humanos , Masculino , Factores de Tiempo , Resultado del Tratamiento
7.
PLoS One ; 9(7): e101385, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25004106

RESUMEN

BACKGROUND: Many studies have shown the suitability of sequence variation in the 5' region of the mitochondrial cytochrome c oxidase I (COI) gene as a DNA barcode for the identification of species in a wide range of animal groups. We examined 471 species in 147 genera of Hemiptera: Auchenorrhyncha drawn from specimens in the Canadian National Collection of Insects to assess the effectiveness of DNA barcoding in this group. METHODOLOGY/PRINCIPAL FINDINGS: Analysis of the COI gene revealed less than 2% intra-specific divergence in 93% of the taxa examined, while minimum interspecific distances exceeded 2% in 70% of congeneric species pairs. Although most species are characterized by a distinct sequence cluster, sequences for members of many groups of closely related species either shared sequences or showed close similarity, with 25% of species separated from their nearest neighbor by less than 1%. CONCLUSIONS/SIGNIFICANCE: This study, although preliminary, provides DNA barcodes for about 8% of the species of this hemipteran suborder found in North America north of Mexico. Barcodes can enable the identification of many species of Auchenorrhyncha, but members of some species groups cannot be discriminated. Future use of DNA barcodes in regulatory, pest management, and environmental applications will be possible as the barcode library for Auchenorrhyncha expands to include more species and broader geographic coverage.


Asunto(s)
Código de Barras del ADN Taxonómico , Hemípteros/clasificación , Hemípteros/genética , Animales , ADN Mitocondrial , Evolución Molecular , Genes de Insecto , Variación Genética
8.
Mol Ecol Resour ; 14(3): 508-18, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24299419

RESUMEN

In this study, we evaluated the efficacy of various primers for the purpose of DNA barcoding old, pinned museum specimens of blackflies (Diptera: Simuliidae). We analysed 271 pinned specimens representing two genera and at least 36 species. Due to the age of our material, we targeted overlapping DNA fragments ranging in size from 94 to 407 bp. We were able to recover valid sequences from 215 specimens, of which 18% had 500- to 658-bp barcodes, 36% had 201- to 499-bp barcodes and 46% had 65- to 200-bp barcodes. Our study demonstrates the importance of choosing suitable primers when dealing with older specimens and shows that even very short sequences can be diagnostically informative provided that an appropriate gene region is used. Our study also highlights the lack of knowledge surrounding blackfly taxonomy, and we briefly discuss the need for further phylogenetic studies in this socioeconomically important family of insects.


Asunto(s)
Código de Barras del ADN Taxonómico/métodos , Cartilla de ADN/genética , Simuliidae/clasificación , Simuliidae/genética , Animales , Complejo IV de Transporte de Electrones/genética , Proteínas de Insectos/genética , Datos de Secuencia Molecular , Museos , Filogenia , Simuliidae/enzimología
10.
Mol Ecol Resour ; 13(2): 168-76, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23228011

RESUMEN

Microgastrine wasps are among the most species-rich and numerous parasitoids of caterpillars (Lepidoptera). They are often host-specific and thus are extensively used in biological control efforts and figure prominently in trophic webs. However, their extraordinary diversity coupled with the occurrence of many cryptic species produces a significant taxonomic impediment. We present and release the results of 8 years (2004-2011) of DNA barcoding microgastrine wasps. Currently they are the best represented group of parasitoid Hymenoptera in the Barcode of Life Data System (BOLD), a massive barcode storage and analysis data management site for the International Barcoding of Life (iBOL) program. There are records from more than 20 000 specimens from 75 countries, including 50 genera (90% of the known total) and more than 1700 species (as indicated by Barcode Index Numbers and 2% MOTU). We briefly discuss the importance of this DNA data set and its collateral information for future research in: (1) discovery of cryptic species and description of new taxa; (2) estimating species numbers in biodiversity inventories; (3) clarification of generic boundaries; (4) biological control programmes; (5) molecular studies of host-parasitoid biology and ecology; (6) evaluation of shifts in species distribution and phenology; and (7) fostering collaboration at national, regional and world levels. The integration of DNA barcoding with traditional morphology-based taxonomy, host records, and other data has substantially improved the accuracy of microgastrine wasp identifications and will significantly accelerate further studies on this group of parasitoids.


Asunto(s)
Código de Barras del ADN Taxonómico , Filogenia , Avispas/clasificación , Avispas/genética , Animales , Secuencia de Bases , Datos de Secuencia Molecular , Análisis de Secuencia de ADN
11.
Mol Ecol ; 20(8): 1772-80, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21366747

RESUMEN

We employ molecular methods to profile the diet of the little brown bat, Myotis lucifugus, and describe spatial and temporal changes in diet over their maternity season. We identified 61 prey species of insects and 5 species of arachnid. The largest proportion of prey (∼32%) were identified as species of the mass-emerging Ephemeroptera (mayfly) genus Caenis. Bats roosting in agricultural settings had lower dietary richness than those occupying a roost located on a forest fragment in a conservation area. We detected temporal fluctuations in diet over the maternity season. Dipteran (fly) species dominated the diet early in the season, replaced later by species of mayfly. Because our methodology provides species-level identification of prey, we were able to isolate environmental indicator species in the diet and draw conclusions about the location and type of their foraging habitat and the health of these aquatic systems. The species detected suggested that the bats use variable habitats; members of one agricultural roost foraged on insects originating in rivers or streams while those in another agricultural roost and the forest roost fed on insects from pond or lake environments. All source water for prey was of fair to good quality, though no species detected are intolerant of pollution thus the habitat cannot be classified as pristine. Our study outlines a model system to investigate the abiotic and biotic interactions between habitat factors through this simple food chain to the top predator.


Asunto(s)
Quirópteros/fisiología , Dieta/veterinaria , Ecosistema , Cadena Alimentaria , Animales , Arácnidos/genética , Insectos/genética , Conducta Predatoria
12.
Mol Ecol Resour ; 11(1): 60-71, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21429101

RESUMEN

DNA barcoding has been adopted as a global bio-identification system for animals in recent years. A major national programme on DNA barcoding of fish and marine life was initiated in India by the authors during 2006 and 115 species of marine fish covering Carangids, Clupeids, Scombrids, Groupers, Sciaenids, Silverbellies, Mullids, Polynemids and Silurids representing 79 Genera and 37 Families from the Indian Ocean have been barcoded for the first time using cytochrome c oxidase I gene (COI) of the mtDNA. The species were represented by multiple specimens and a total of 397 sequences were generated. After amplification and sequencing of 707 base pair fragment of COI, primers were trimmed which invariably generated a 655 base pair barcode sequence. The average Kimura two parameter (K2P) distances within species, genera, families, orders were 0.30%, 6.60%, 9.91%, 16.00%, respectively. In addition to barcode-based species identification system, phylogenetic relationships among the species have also been attempted. The neighbour-joining tree revealed distinct clusters in concurrence with the taxonomic status of the species.


Asunto(s)
Código de Barras del ADN Taxonómico/métodos , Peces/clasificación , Filogenia , Animales , ADN Mitocondrial/genética , Complejo IV de Transporte de Electrones/genética , Proteínas de Peces/genética , Peces/genética , India , Datos de Secuencia Molecular
13.
Bull Entomol Res ; 101(4): 429-34, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21272395

RESUMEN

Although DNA barcode coverage has grown rapidly for many insect orders, there are some groups, such as scale insects, where sequence recovery has been difficult. However, using a recently developed primer set, we recovered barcode records from 373 specimens, providing coverage for 75 species from 31 genera in two families. Overall success was >90% for mealybugs and >80% for armored scale species. The G·C content was very low in most species, averaging just 16.3%. Sequence divergences (K2P) between congeneric species averaged 10.7%, while intra-specific divergences averaged 0.97%. However, the latter value was inflated by high intra-specific divergence in nine taxa, cases that may indicate species overlooked by current taxonomic treatments. Our study establishes the feasibility of developing a comprehensive barcode library for scale insects and indicates that its construction will both create an effective system for identifying scale insects and reveal taxonomic situations worthy of deeper analysis.


Asunto(s)
Código de Barras del ADN Taxonómico , Hemípteros/genética , Animales , Complejo IV de Transporte de Electrones/genética , Femenino , Hemípteros/clasificación , Masculino
14.
Mol Ecol Resour ; 10(4): 606-14, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21565065

RESUMEN

Species identification of earthworms is usually achieved by careful observation of morphological features, often sexual characters only present in adult specimens. Consequently, juveniles or cocoons are often impossible to identify, creating a possible bias in studies that aim to document species richness and abundance. DNA barcoding, the use of a short standardized DNA fragment for species identification, is a promising approach for species discrimination. When a reference library is available, DNA-based identification is possible for all life stages. In this study, we show that DNA barcoding is an unrivaled tool for high volume identification of juvenile earthworms. To illustrate this advance, we generated DNA barcodes for specimens of Lumbricus collected from three temperate grasslands in western France. The analysis of genetic distances between individuals shows that juvenile sequences unequivocally match DNA barcode clusters of previously identified adult specimens, demonstrating the potential of DNA barcoding to provide exhaustive specimen identification for soil ecological research.

15.
Mol Ecol ; 18(24): 5161-79, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19912535

RESUMEN

A major question in our understanding of eukaryotic biodiversity is whether small bodied taxa have cosmopolitan distributions or consist of geographically localized cryptic taxa. Here, we explore the global phylogeography of the freshwater cladoceran Polyphemus pediculus (Linnaeus, 1761) (Crustacea, Onychopoda) using two mitochondrial genes, cytochrome c oxidase subunit I and 16s ribosomal RNA, and one nuclear marker, 18s ribosomal RNA. The results of neighbour-joining and Bayesian phylogenetic analyses reveal an exceptionally pronounced genetic structure at both inter- and intra-continental scales. The presence of well-supported, deeply divergent phylogroups across the Holarctic suggests that P. pediculus represents an assemblage of at least nine, largely allopatric cryptic species. Interestingly, all phylogenetic analyses support the reciprocal paraphyly of Nearctic and Palaearctic clades. Bayesian inference of ancestral distributions suggests that P. pediculus originated in North America or East Asia and that European lineages of Polyphemus were established by subsequent intercontinental dispersal events from North America. Japan and the Russian Far East harbour exceptionally high levels of genetic diversity at both regional and local scales. In contrast, little genetic subdivision is apparent across the formerly glaciated regions of Europe and North America, areas that historical demographic analyses suggest that were recolonized just 5500-24 000 years ago.


Asunto(s)
Cladóceros/genética , Evolución Molecular , Variación Genética , Filogenia , Animales , Teorema de Bayes , ADN Mitocondrial/genética , Complejo IV de Transporte de Electrones/genética , Agua Dulce , Genética de Población , Geografía , Haplotipos , Dinámica Poblacional , ARN Ribosómico 16S/genética , ARN Ribosómico 18S/genética , Alineación de Secuencia , Análisis de Secuencia de ADN , Zooplancton/genética
16.
J Fish Biol ; 74(2): 329-56, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20735564

RESUMEN

FISH-BOL, the Fish Barcode of Life campaign, is an international research collaboration that is assembling a standardized reference DNA sequence library for all fishes. Analysis is targeting a 648 base pair region of the mitochondrial cytochrome c oxidase I (COI) gene. More than 5000 species have already been DNA barcoded, with an average of five specimens per species, typically vouchers with authoritative identifications. The barcode sequence from any fish, fillet, fin, egg or larva can be matched against these reference sequences using BOLD; the Barcode of Life Data System (http://www.barcodinglife.org). The benefits of barcoding fishes include facilitating species identification, highlighting cases of range expansion for known species, flagging previously overlooked species and enabling identifications where traditional methods cannot be applied. Results thus far indicate that barcodes separate c. 98 and 93% of already described marine and freshwater fish species, respectively. Several specimens with divergent barcode sequences have been confirmed by integrative taxonomic analysis as new species. Past concerns in relation to the use of fish barcoding for species discrimination are discussed. These include hybridization, recent radiations, regional differentiation in barcode sequences and nuclear copies of the barcode region. However, current results indicate these issues are of little concern for the great majority of specimens.


Asunto(s)
Código de Barras del ADN Taxonómico , Animales , ADN Mitocondrial/genética , Complejo IV de Transporte de Electrones/genética , Peces/genética , Genes Mitocondriales , Especificidad de la Especie
17.
J Fish Biol ; 74(2): 377-402, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20735566

RESUMEN

The freshwater fish fauna of Mexico and Guatemala is exceptionally diverse with >600 species, many endemic. In this study, patterns of sequence divergence were analysed in representatives of this fauna using cytochrome c oxidase subunit 1 (COI) DNA barcodes for 61 species in 36 genera. The average divergence among conspecific individuals was 0.45%, while congeneric taxa showed 5.1% divergence. Three species of Poblana, each occupying a different crater lake in the arid regions of Central Mexico, have had a controversial taxonomic history but are usually regarded as endemics to a single lake. They possess identical COI barcodes, suggesting a very recent history of isolation. Representatives of the Cichlidae, a complex and poorly understood family, were well discriminated by barcodes. Many species of Characidae seem to be young, with low divergence values (<2%), but nevertheless, clear barcode clusters were apparent in the Bramocharax-Astyanax complex. The symbranchid, Opisthernon aenigmaticum, has been regarded as a single species ranging from Guatemala to Mexico, but it includes two deeply divergent barcode lineages, one a possible new endemic species. Aside from these special cases, the results confirm that DNA barcodes will be highly effective in discriminating freshwater fishes from Central America and that a comprehensive analysis will provide new important insights for understanding diversity of this fauna.


Asunto(s)
Código de Barras del ADN Taxonómico , Peces/genética , Variación Genética , Animales , ADN Mitocondrial/genética , Complejo IV de Transporte de Electrones/genética , Evolución Molecular , Peces/clasificación , Agua Dulce , Guatemala , México , Filogenia , Análisis de Secuencia de ADN , Especificidad de la Especie
18.
Mol Ecol Resour ; 9 Suppl s1: iv-vi, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-21564959
19.
Mol Ecol Resour ; 8(6): 1189-201, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21586006

RESUMEN

A 658-bp fragment of mitochondrial DNA from the 5' region of the mitochondrial cytochrome c oxidase 1 (COI) gene has been adopted as the standard DNA barcode region for animal life. In this study, we test its effectiveness in the discrimination of over 300 species of aphids from more than 130 genera. Most (96%) species were well differentiated, and sequence variation within species was low, averaging just 0.2%. Despite the complex life cycles and parthenogenetic reproduction of aphids, DNA barcodes are an effective tool for identification.

20.
Vox Sang ; 93(1): 1-11, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17547559

RESUMEN

BACKGROUND AND OBJECTIVE: Identifying factors that can predict adults at high risk of receiving red blood cell transfusion during coronary artery bypass graft (CABG) surgery may aid in more efficient blood banking practices and may tailor blood conservation strategies for these adult patients. The objective was to identify clinical factors associated with increased red cell transfusion in adults undergoing CABG surgery. METHODS: A systematic review of the MEDLINE and HealthSTAR databases from 1966 to December 2005 was conducted. Citations containing the medical subject heading or textwords 'coronary artery bypass graft', 'CABG' and 'cardiovascular surgery' were combined with the medical subject headings or textwords 'transfusion' and 'blood transfusion'. RESULTS: A total of 2461 abstracts were retrieved. Twenty-one studies met the inclusion/exclusion criteria. Transfusion rates ranged from 7 to 97%. Several variables were identified that were associated with increased red cell transfusion rates including older age, female sex, low haemoglobin concentration or haematocrit value, renal insufficiency and urgent/emergent surgery. The strongest risk factor was the urgency of surgery (urgent or emergent surgery), which was associated with a 4x to 8x increase in transfusion rates compared to elective surgery. Increasing age and female sex increased the likelihood of transfusion by 1x to 3x and 2x, respectively. CONCLUSIONS: Increasing patient age, female sex, lower preoperative haemoglobin levels, as well as the urgency of the CABG surgery were associated with higher transfusion rates. Identifying risk factors for transfusion may allow for targeted use of blood conservation strategies, improved efficiency in blood utilization and informing adults at risk of transfusion.


Asunto(s)
Bancos de Sangre , Conservación de la Sangre , Puente de Arteria Coronaria , Transfusión de Eritrocitos , Eritrocitos , Adulto , Factores de Edad , Femenino , Hematócrito , Hemoglobinas , Humanos , MEDLINE , Masculino , Educación del Paciente como Asunto , Factores de Riesgo , Factores Sexuales , Factores de Tiempo
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