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41.
42.
Rodríguez-Sánchez C Sittenfeld A Janzen DH Espinoza AM 《Revista de biología tropical》2006,54(2):265-271
Bacillus thuringiensis (Bt) synthesizes crystalline inclusions that are toxic to caterpillars (Lepidoptera) and other orders of invertebrates. Materials associated with 37 caterpillars from 16 species, collected while feeding on 15 different species of host plants in dry, cloud and rain forests located in the Area de Conservación Guanacaste in northwestern Costa Rica, were examined for the presence of Bt. From a total of 101 derived samples, 25 Bt isolates were cultured: 56% from host plant leaves, 8% from caterpillar guts and 36% from caterpillar fecal pellets. Bt was isolated from at least one sample in 38% of the systems constituted by the food plant, gut and fecal pellets corresponding to a single caterpillar. Four different morphologies of crystalline inclusions were observed, with bipyramidal and irregular crystal morphologies being the most prevalent. 相似文献
43.
When attacked, many decapod crustaceans perform tailflips, which are triggered by a neural circuit that includes lateral giant interneurons, medial giant interneurons, and fast flexor motor giant neurons (MoGs). Slipper lobsters (Scyllaridae) lack these giant neurons, and it has been hypothesized that behavioral (e.g., digging) and morphological (e.g., flattening and armor) specializations in this group caused the loss of escape-related giant neurons. To test this hypothesis, we examined a species of spiny lobster, Panulirus argus. Spiny lobsters belong to the sister taxon of the scyllarids, but they have a more crayfish-like morphology than scyllarids and were predicted to have escape-related giant neurons. Ventral nerve cords of P. argus were examined using paraffin-embedded sections and cobalt backfills. We found no escape-related giant neurons and no large axon profiles in the dorsal region of the nerve cord of P. argus. Cobalt backfills showed one fewer fast flexor motor neuron than in species with MoGs and none of the fast flexor motor neurons show any of the anatomical specializations of MoGs. This suggests that all palinuran species lack this giant escape circuit, and that the loss of rapid escape behavior preceded, and may have driven, alternative predator avoidance and anti-predator strategies in palinurans. 相似文献
44.
Morales-Bozo I Rojas G Ortega-Pinto A Espinoza I Soto L Plaza A Lozano C Urzúa B 《Gerodontology》2012,29(2):e1103-e1112
doi: 10.1111/j.1741‐2358.2012.00626.x Evaluation of the efficacy of two mouthrinses formulated for the relief of xerostomia of diverse origin in adult subjects Objective: To evaluate the efficacy of two new mouthrinses in the reduction of xerostomía‐associated symptomatology. Background: Xerostomia is a common chronic health condition that affects a great number of adults and significantly deteriorates quality of life, such that treatment is necessary. Materials and methods: Sixty‐seven adult subjects of both sexes presenting xerostomia of diverse origin were selected. Mouthrinses were tested using a double‐blind, randomized, cross‐over clinical trial with an intervining wash out period. Results: The 100% of subjects presented sensation of dry mouth, and 86% stated sensation of thick saliva. Burning tongue sensation, need to drink liquids to swallow and the sensation of swallowing difficulty were recorded in more than 50% of the patients. The most frequent pathologies in the sample were depression, arthritis, and arterial hypertension. Results of the clinical tests showed that mouthrinse 1 relieves sensation of dry mouth, need to drink liquids, and swallowing difficulty. In contrast, mouthrinse 2 relieves only latter two symptoms. Both rinses were more effective in relieving xerostomía‐associated symptomatology in patients taking 3 or more medicines simultaneously. Conclusion: Both mouthrinses were effective in relieving various xerostomia symptoms, could be distributed at a low cost, thereby improving the quality of life of population affected. 相似文献
45.
46.
Espinoza Ldel C Huguet T Julier B 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(4):739-754
Medicago truncatula, as a model species, is useful to study the genetic control of traits of agronomic interest in legumes species. Aerial morphogenesis
is a key component of forage and seed yield. It was measured in four mapping populations originating from five parental lines.
Single and multi-population quantitative trait locus (QTL) detections were carried out. A large variation was observed within
populations and transgressive segregation was noted. Most traits showed high heritabilities in all seasons. Length of primary
branches (LPB, cm) was positively correlated to branch elongation rate (BER, cm day−1) and aerial dry matter (ADM, g). Flowering time (FT, °C day−1) showed negative correlations with length of main stem (LMS, cm) and BER. One hundred and forty-one QTLs for BER, LMS, FT,
LPB, diameter of primary branches (DPB), number of primary branches (NPB), number of nodes (NI) and ADM were identified and
localized over all eight chromosomes. Single and multi-population analyses showed that the most important regions for aerial
morphogenetic traits were chromosomes 1, 2, 7 and 8. Multi-population analysis revealed three regions of major QTLs affecting
aerial morphogenetic traits (LPB, LMS, NPB, BER and FT). A region involved in flowering time variation was revealed on chromosome
6 on a single population. These results were used to identify candidate genes that could control variation for aerial morphogenesis
traits in this species and in related crop legume species. 相似文献
47.
Rodríguez ES Pose AG Moltó MP Espinoza AS Zamora PA Pedroso MS 《Biotechnology journal》2012,7(8):1049-1053
The production of recombinant proteins in the milk of non-transgenic goats can be achieved by transducing the mammary gland with recombinant adenoviral vectors. However, this process involves several regulatory issues. The current study evaluates the biosafety of this production system. We present a preliminary biosafety profile based on detection of adenoviral particles in different body fluids and the antibody response after adenoviral transduction of the goat mammary gland. In addition, two methods of adenoviral inactivation in milk were tested. Although adenoviral particles were detected in the milk until day 4 after transduction, they were absent in serum, saliva, urine and feces. Anti-adenovirus antibodies were detected in serum and milk. The virus inactivation methods neutralized adenoviral particles and preserved the immunological identity of the recombinant protein. These results support the idea of a safe production of recombinant proteins using adenoviral vectors. 相似文献
48.
Despite numerous endometrial cancer cell lines, little is know about the progression and transition of primary cultured endometrial tumours. Herein, a stage I grade III endometrial adenocarcinoma was maintained in primary culture and the phenotypic and protein expression changes were observed in relation to passage number. At early passage numbers, cultured human endometrial cancer (CHEC) cells displayed classic epithelial cell morphology, growing in groups in a glandular structure and staining positive for cytokeratin. However, with increasing passage number, CHEC cells changed in morphology to display a stromal phenotype which was accompanied by a significant reduction in cytokeratin and increases in alpha-actin and vimentin expression. Simultaneous culture of stromal cells isolated from the original tumour failed to show the same morphological characteristics or protein expression patterns. We further characterised CHEC cells through a screening of cancer related proteins, among others, caveolin-1 and Tissue factor in comparison with established cancer cell lines and corresponding non-cancerous cells. This report demonstrates that endometrial adenocarcinoma cells in culture can undergo phenotypic and protein expression changes reminiscent of epithelial-mesenchymal transition. This work suggests that primary tumours and cell lines displaying stromal morphologies may have undergone epithelial-mesenchymal transition from an adenocarcinoma origin. 相似文献
49.
L. A. Siena M. E. Sartor F. Espinoza C. L. Quarin J. P. A. Ortiz 《Sexual plant reproduction》2008,21(3):205-215
Gametophytic apomixis is an asexual mode of reproduction by seeds. This trait is present in several plant families and is
strongly associated with polyploidy. Paspalum rufum is a forage grass with sexual self-incompatible diploids (2n = 2x = 20) and aposporous-apomictic pseudogamous tetraploids (2n = 4x = 40). In previous work embryological observations of the diploid genotype Q3754 showed 8.8–26.8% of the ovaries having one
meiotic plus an aposporous-like embryo sac, suggesting some capability for apomictic reproduction. The objective of this work
was to characterize progenies derived from Q3754 to determine if aposporous sacs were functional and generated progenies via
apomixis at the diploid level. Re-examination of Q3754 ovaries showed that 12.5% of them contained one sexual plus an aposporous
sac confirming previous results. Progeny tests were carried out on two experimental families (H1 and S1) employing heterozygous RAPD marker loci. Family H1 was obtained crossing Q3754 with a natural diploid genotype (Q3861) and S1 derived from the induced self-pollination of Q3754. Genetic analysis of H1 showed that all individuals derived from sexual reproduction. However, 5 out of 95 plants from S1 showed the same heterozygous state as the mother plant for 14 RAPD loci suggesting a clonal origin. Further experiments,
designed to test the functionality of aposporous sacs by flow cytometric analyses, were carried out on a third family (M1) obtained by crossing Q3754 with the tetraploid plant Q3785. Histograms of 20 M1 plants showed 15 diploids (75%), 4 triploids (20%) and 1 tetraploid (5%). Triploids and the tetraploid may have originated
from functional aposporous embryo sacs. Likewise, the reconstruction of the developmental route of 40 individual seeds demonstrated
that 11 of them (27.5%) derived from fertilized aposporic sacs. The results presented in this work indicate that gametophytic
apomixis is effectively expressed at the diploid level in Paspalum rufum and could be the foundation of a recurrent auto-polyploidization process in the species. 相似文献
50.
M Amparo Andrade Mar Siles-Lucas José Luis Pérez Arellano Cristina Pou Barreto Basilio Valladares Elsa Espinoza Antonio Muro 《Nitric oxide》2005,13(4):217-225
Dirofilaria immitis is a worldwide filarial nematode causing heartworm disease in dogs and cats. Several mosquito species, which are able to feed both on humans and animals, can transmit this parasite. Inflammatory progression of host tissues induced by parasites are mediated by several molecules, including nitric oxide (NO), which usually exerts deleterious effects on parasites and occasionally on the host. We analyze the in vitro effect of total D. immitis adult worm somatic antigens on na?ve rat alveolar macrophage NO production and further separation of parasite proteins to define specific D. immitis somatic molecules influencing host cell NO secretion. Additionally, we address the possible influence of Wolbachia spp. on the in vitro production of NO by macrophages. Our results demonstrate that D. immitis adult worm soluble antigens are able to specifically induce NO production from host macrophages. Furthermore, we demonstrated that this effect is due to nematode antigens rather than to defined components (LPS and metabolic molecules) derived from its endosymbiont, Wolbachia spp. In addition, we were able to isolate and identify one of the parasite specific components from the DiSo extract, denominated DiID35.3 and putatively belonging to the Immunoglobulin Superfamily Protein (ISP) group, triggering NO release from macrophages in a dose-dependent and specific manner. 相似文献