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2.
Arch Insect Biochem Physiol ; 102(2): e21604, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31328823

RESUMEN

Benzoylphenyl ureas inhibit chitin synthesis and interfere with the molting process in arthropods. In this study, the effect of diflubenzuron on third-instar larvae of Aedes aegypti was evaluated. The susceptibility to the product was determined, and the alterations generated were shown through light and electron microscopy. LC50 and LC90 were 0.23 and 0.47 ppm, respectively. The main alterations observed were the incapacity to complete the molt, a reduction of mobility, the fragmentation of the old cuticle, a division of the body segments that was not evident, and the deformation of the caudal structures. Images of the ultrastructure are included, where breaking zones in the cuticle were observed, separation of the cuticle, the epidermis and the muscles, and these latter with a disorganized arrangement. In low concentrations, from 0.15 ppm, diflubenzuron causes alterations in the behavior and morphology of Ae. aegypti.

3.
Zootaxa ; 4375(3): 358-370, 2018 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-29690076

RESUMEN

Comadia redtenbacheri (Hammerschmidt) (Agave Red Worm) is the only member of the family Cossidae that has been described as a phytophagous specialist of the plant genus Agave, which is mainly distributed in México. A new extraction protocol adapted from Stewart Via (1993) has been implemented for sequencing the COI gene from samples collected in five states of the North Central (Querétaro and Zacatecas), South Central (Estado de México) and East Central (Hidalgo and Tlaxcala) regions of México with the purpose of contributing to delineation of the species. A Maximum Likelihood (ML) tree based on these COI sequences as well as COI sequences from other Cossinae species was developed to complement the existing morphological and taxonomic approaches to delineation of this species. As expected, our Comadia samples cluster together within a monophyletic clade that includes four C. redtenbacheri sequences previously reported. This group seems to be consistent with our reconstruction, which is supported by a bootstrap value of over 99%. The closely related branches associated with the latter group include organisms known to be the plant and tree borers of the Cossinae subfamily. The COI sequences from our samples were analyzed to determine the percentage of identity among the C. redtenbacheri in a first attempt to detect differences in the sequence that matches a particular region of México.


Asunto(s)
Lepidópteros , Agave , Animales , México , Filogenia
4.
Microb Pathog ; 109: 162-168, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28578091

RESUMEN

Argemone mexicana, Taraxacum officinale, Ruta chalepensis and Tagetes filifolia are plants with deworming potential. The purpose of this study was to evaluate methanolic extracts of aerial parts of these plants against Haemonchus contortus eggs and infective larvae (L3) and identify compounds responsible for the anthelmintic activity. In vitro probes were performed to identify the anthelmintic activity of plant extracts: egg hatching inhibition (EHI) and larvae mortality. Open column Chromatography was used to bio-guided fractionation of the extract, which shows the best anthelmintic effect. The lethal concentration to inhibit 50% of H. contortus egg hatching or larvae mortality (LC50) was calculated using a Probit analysis. Bio-guided procedure led to the recognition of an active fraction (TF11) mainly composed by 1) quercetagitrin, 2) methyl chlorogenate and chlorogenic acid. Quercetagitrin (1) and methyl chlorogenate (2) did not show an important EHI activity (3-14%) (p < 0.05); however, chlorogenic acid (3) showed 100% of EHI (LC50 248 µg/mL) (p < 0.05). Chlorogenic acid is responsible of the ovicidal activity and it seems that, this compound is reported for the first time with anthelmintic activity against a parasite of importance in sheep industry.


Asunto(s)
Antihelmínticos/farmacología , Argemone/química , Haemonchus/efectos de los fármacos , Larva/efectos de los fármacos , Extractos Vegetales/farmacología , Ruta/química , Tagetes/química , Taraxacum/química , Animales , Ácido Clorogénico/análogos & derivados , Ácido Clorogénico/farmacología , Huevos , Cara/parasitología , Dosificación Letal Mediana , México , Infecciones por Nematodos , Extractos Vegetales/química , Metabolismo Secundario , Ovinos , Enfermedades de las Ovejas/tratamiento farmacológico , Enfermedades de las Ovejas/parasitología
5.
J Invertebr Pathol ; 113(3): 232-6, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23623900

RESUMEN

Solenopsis invicta virus 1 (SINV-1) was found regularly and prevalently in S. invicta. In sampled locations where S. invicta and S. geminata are sympatric (specifically, Gainesville, FL and Travis, TX), SINV-1 was detected in S. geminata. Conversely, in areas in which S. geminata and S. invicta are allopatric, SINV-1 was not detected in S. geminata; these locations included north Australia (n=12), southern Mexico (n=107), Hawaii (n=48), Taiwan (n=12), and the Johnston Atoll (n=6). A similar relationship was observed for S. richteri. In areas in which S. invicta and S. richteri were sympatric, SINV-1 was detected in the S. richteri population, but in areas in which S. invicta and S. richteri were allopatric, SINV-1 was not detected. These occurrences suggest that S. invicta is the host of predilection, or preferred host for SINV-1, and that the congenerics, S. geminata and S. richteri serve as either accidental, reservoir, or transfer hosts. The minus genome strand of SINV-1 was detected in S. geminata and S. richteri indicating that these species may serve as functional hosts capable of supporting SINV-1 replication. SINV-1 was not detected in S. xyloni regardless of its proximity to S. invicta. These results suggest that SINV-1 may be an example of pathogen spillover or pollution.


Asunto(s)
Hormigas/virología , Interacciones Huésped-Patógeno , Virus de Insectos/fisiología , Animales , Geografía , Replicación Viral
6.
J Invertebr Pathol ; 105(3): 279-88, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20691187

RESUMEN

Kneallhazia solenopsae is a pathogenic microsporidium that infects the fire ants Solenopsis invicta and Solenopsis richteri in South America and the USA. In this study, we analyzed the prevalence and molecular diversity of K. solenopsae in fire ants from North and South America. We report the first empirical evidence of K. solenopsae infections in the tropical fire ant, Solenopsis geminata, and S. geminata×Solenopsis xyloni hybrids, revealing an expanded host range for this microsporidium. We also analyzed the molecular diversity at the 16S ribosomal RNA gene in K. solenopsae from the ant hosts S.invicta, S. richteri, S. geminata and S. geminata×S. xyloni hybrids from North America, Argentina and Brazil. We found 22 16S haplotypes. One of these haplotypes (WD_1) appears to be widely distributed, and is found in S. invicta from the USA and S. geminata from southern Mexico. Phylogenetic analyses of 16S sequences revealed that K. solenopsae haplotypes fall into one of two major clades that are differentiated by 2-3%. In some cases, multiple K. solenopsae haplotypes per colony were found, suggesting either an incomplete homogenization among gene copies within the 16S gene cluster or multiple K. solenopsae variants simultaneously infecting host colonies.


Asunto(s)
Hormigas/microbiología , Microsporidios/genética , Microsporidiosis/epidemiología , Animales , Secuencia de Bases , Genes Fúngicos/genética , Haplotipos , Microsporidia no Clasificados/genética , Microsporidiosis/genética , Datos de Secuencia Molecular , América del Norte , Filogenia , Prevalencia , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
7.
J Invertebr Pathol ; 96(1): 18-27, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17412359

RESUMEN

Studies were conducted to examine the phenology, geographic distribution, and host specificity of the Solenopsis invicta virus-1 (SINV-1). Two genotypes examined, SINV-1 and -1A, exhibited similar seasonal prevalence patterns. Infection rates among colonies of S. invicta in Gainesville, Florida, were lowest from early winter (December) to early spring (April) increasing rapidly in late spring (May) and remaining high through August before declining again in the fall (September/October). Correlation analysis revealed a significant relationship between mean monthly temperature and SINV-1 (p<0.0005, r=0.82) and SINV-1A (p<0.0001, r=0.86) infection rates in S. invicta colonies. SINV-1 was widely distributed among S. invicta populations. The virus was detected in S. invicta from Argentina and from all U.S. states examined, with the exception of New Mexico. SINV-1 and -1A were also detected in other Solenopsis species. SINV-1 was detected in Solenopsis richteri and the S. invicta/richteri hybrid collected from northern Alabama and Solenopsis geminata from Florida. SINV-1A was detected in S. geminata and Solenopsis carolinensis in Florida and the S. invicta/richteri hybrid in Alabama. Of the 1989 arthropods collected from 6 pitfall trap experiments from Gainesville and Williston, Florida, none except S. invicta tested positive for SINV-1 or SINV-1A. SINV-1 did not appear to infect or replicate within Sf9 or Dm-2 cells in vitro. The number of SINV-1 genome copies did not significantly increase over the course of the experiment, nor were any cytopathic effects observed. Phylogenetic analyses of SINV-1/-1A nucleotide sequences indicated significant divergence between viruses collected from Argentina and the U.S.


Asunto(s)
Hormigas/virología , Genoma Viral , Interacciones Huésped-Parásitos/fisiología , Infecciones por Picornaviridae/epidemiología , Picornaviridae/genética , Secuencia de Aminoácidos , Animales , Datos de Secuencia Molecular , Filogenia , Infecciones por Picornaviridae/veterinaria , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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