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21.
G. Taret M. Sevilla V. Wornoayporn A. Islam S. Ahmad C. Caceres A. S. Robinson M. J. B. Vreysen 《Journal of Applied Entomology》2010,134(3):207-215
The codling moth Cydia pomonella (Linnaeus) (Lepidoptera: Tortricidae) is a serious pest of pome fruit worldwide and the sterile insect technique (SIT) provides an environmentally acceptable approach for its control. As the pest is present in both the southern and northern hemispheres it would be possible for a rearing facility in the northern hemisphere to supply sterile moths to an SIT programme in the southern hemisphere during the northern winter and vice versa. This could greatly improve the economics of moth production and the running costs of rearing facilities. However in order to develop this concept, it is important to assess if populations of codling moth from different geographical regions share mating compatibility. Twelve different laboratory and field populations from both hemispheres were sampled and field cage bisexual mating compatibility tests were carried out between selected combinations. The index of sexual isolation (ISI) and the female and male relative performance index (FRPI and MRPI, respectively) were calculated for each mating combination. In only two of the combinations was there a slight but significant deviation from random mating. There were also some significant differences in mating duration between the homotypic matings and the duration of a particular homotypic mating seemed to depend on the origin of the other population in the cage. It was concluded that there exist no barriers to mating between populations of codling moth from many parts of the world and that it would be feasible for sterile moths to be shipped from one rearing facility to SIT programmes in other parts of the world. 相似文献
22.
Peter L. Irwin Michael D. Sevilla James J. Shieh 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》1984,805(2):186-190
Electron spin resonance linewidth measurements have been made on intact cell walls exchanged with various combinations of Mn2+ and Ca2+. These experiments were performed to find the Mn2+ nearest-neighbor distance and thereby determine whether carboxylate-Mn2+ complexes potentiate ion association at adjacent sites on cell wall polyuronides. Our results show that as the fraction of available binding sites occupied by Mn2+ increased from 2% to 27%, the nearest-neighbor distance parameter decreased only from 14 to 11 Å. These distances are close to polyuronide interanionic spacings. The small change in the distance parameter with concentration is evidence for sequential rather than random binding. Competitive ion-exchange with Ca2+ was found to reduce the Mn2+ spin-spin line broadening at similar total bound Mn2+ concentrations. This is expected only if Ca2+ competes at adjacent sites. The data presented offer strong support for the hypothesis that carboxylate groups near already occupied sites have a greater affinity for divalent cations than other sites along the polyuronide main chain. 相似文献
23.
Mice deficient in involucrin, envoplakin, and periplakin have a defective epidermal barrier 总被引:2,自引:0,他引:2
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Sevilla LM Nachat R Groot KR Klement JF Uitto J Djian P Määttä A Watt FM 《The Journal of cell biology》2007,179(7):1599-1612
The cornified envelope is assembled from transglutaminase cross-linked proteins and lipids in the outermost epidermal layers and is essential for skin barrier function. Involucrin, envoplakin, and periplakin form the protein scaffold on which the envelope assembles. To examine their combined function, we generated mice deficient in all three genes. The triple knockouts have delayed embryonic barrier formation and postnatal hyperkeratosis (abnormal accumulation of cornified cells) resulting from impaired desquamation. Cornified envelopes form but are ultrastructurally abnormal, with reduced lipid content and decreased mechanical integrity. Expression of proteases is reduced and the protease inhibitor, serpina1b, is highly upregulated, resulting in defective filaggrin processing and delayed degradation of desmoglein 1 and corneodesmosin. There is infiltration of CD4+ T cells and a reduction in resident γδ+ T cells, reminiscent of atopic dermatitis. Thus, combined loss of the cornified envelope proteins not only impairs the epidermal barrier, but also changes the composition of T cell subpopulations in the skin. 相似文献
24.
Fernando L Hernando Esther Calvo Ana Abad Andoni Ramírez Aitor Rementería María J Sevilla José Pontón 《International microbiology》2007,10(2):103-108
Antigens from Candida albicans blastoconidia and germ tubes were identified by two-dimensional electrophoresis and Western blotting and characterized by microsequencing, reactivity with concanavalin A, and a panel of human sera. Antigens identified included a polydispersed area in the acidic high-molecular-mass regions of blastoconidium and germ-tube extracts, and 16 antigens varying in molecular masses and isoelectric points (pIs). The majority of the detected antigens, especially those in the polydispersed region, showed mannosyl groups, as determined by concanavalin A reactivity. Antibodies present in sera from patients with invasive candidiasis showed high reactivity with a number of antigens not detected with sera from blood donors. Eight of the 16 antigens could be identified by reactivity with monoclonal antibodies or by microsequencing. Five antigens showed homology with five enzymes previously described as antigens in C. albicans: enolase, phosphoglycerate kinase, malate dehydrogenase, and two isoforms of the fructose biphosphate aldolase. However, to our knowledge, this is the first report of the immunogenic activity of a kexin precursor, a mitochondrial complex I chaperone, and a diacylglycerol kinase catalytic domain from C. albicans. Antigens described in this study may be of potential interest for the serodiagnosis of invasive candidiasis. 相似文献
25.
Iker Irisarri Miguel Vences Diego San Mauro Frank Glaw Rafael Zardoya 《BMC evolutionary biology》2011,11(1):114
Background
Evolutionary novelties often appear by conferring completely new functions to pre-existing structures or by innovating the mechanism through which a particular function is performed. Sound production plays a central role in the behavior of frogs, which use their calls to delimit territories and attract mates. Therefore, frogs have evolved complex vocal structures capable of producing a wide variety of advertising sounds. It is generally acknowledged that most frogs call by moving an air column from the lungs through the glottis with the remarkable exception of the family Pipidae, whose members share a highly specialized sound production mechanism independent of air movement.Results
Here, we performed behavioral observations in the poorly known African pipid genus Pseudhymenochirus and document that the sound production in this aquatic frog is almost certainly air-driven. However, morphological comparisons revealed an indisputable pipid nature of Pseudhymenochirus larynx. To place this paradoxical pattern into an evolutionary framework, we reconstructed robust molecular phylogenies of pipids based on complete mitochondrial genomes and nine nuclear protein-coding genes that coincided in placing Pseudhymenochirus nested among other pipids.Conclusions
We conclude that although Pseudhymenochirus probably has evolved a reversal to the ancestral non-pipid condition of air-driven sound production, the mechanism through which it occurs is an evolutionary innovation based on the derived larynx of pipids. This strengthens the idea that evolutionary solutions to functional problems often emerge based on previous structures, and for this reason, innovations largely depend on possibilities and constraints predefined by the particular history of each lineage.26.
27.
Background
The gene transformer-2, which is involved in sex determination, has been studied in Drosophila, Musca, Ceratitis, Anastrepha and Lucilia. All these members of Diptera belong to the suborder Brachycera. In this work, it is reported the isolation and characterisation of genes transformer-2 of the dipterans Sciara ocellaris and Bradysia coprophila (formerly Sciara coprophila), which belong to the much less extensively analysed Sciaridae Family of the Suborder Nematocera, which is paraphyletic with respect to Suborder Brachycera. 相似文献28.
Lonardo E Hermann PC Mueller MT Huber S Balic A Miranda-Lorenzo I Zagorac S Alcala S Rodriguez-Arabaolaza I Ramirez JC Torres-Ruíz R Garcia E Hidalgo M Cebrián DÁ Heuchel R Löhr M Berger F Bartenstein P Aicher A Heeschen C 《Cell Stem Cell》2011,9(5):433-446
Nodal and Activin belong to the TGF-β superfamily and are important regulators of embryonic stem cell fate. Here we investigated whether Nodal and Activin regulate self-renewal of pancreatic cancer stem cells. Nodal and Activin were hardly detectable in more differentiated pancreatic cancer cells, while cancer stem cells and stroma-derived pancreatic stellate cells markedly overexpressed Nodal and Activin, but not TGF-β. Knockdown or pharmacological inhibition of the Nodal/Activin receptor Alk4/7 in cancer stem cells virtually abrogated their self-renewal capacity and in vivo tumorigenicity, and reversed the resistance of orthotopically engrafted cancer stem cells to gemcitabine. However, engrafted primary human pancreatic cancer tissue with a substantial stroma showed no response due to limited drug delivery. The addition of a stroma-targeting hedgehog pathway inhibitor enhanced delivery of the Nodal/Activin inhibitor and translated into long-term, progression-free survival. Therefore, inhibition of the Alk4/7 pathway, if combined with hedgehog pathway inhibition and gemcitabine, provides a therapeutic strategy for targeting cancer stem cells. 相似文献
29.
Garrido JM Sevilla IA Beltrán-Beck B Minguijón E Ballesteros C Galindo RC Boadella M Lyashchenko KP Romero B Geijo MV Ruiz-Fons F Aranaz A Juste RA Vicente J de la Fuente J Gortázar C 《PloS one》2011,6(9):e24905
Tuberculosis (TB) caused by Mycobacterium bovis and closely related members of the Mycobacterium tuberculosis complex continues to affect humans and animals worldwide and its control requires vaccination of wildlife reservoir species such as Eurasian wild boar (Sus scrofa). Vaccination efforts for TB control in wildlife have been based primarily on oral live BCG formulations. However, this is the first report of the use of oral inactivated vaccines for controlling TB in wildlife. In this study, four groups of 5 wild boar each were vaccinated with inactivated M. bovis by the oral and intramuscular routes, vaccinated with oral BCG or left unvaccinated as controls. All groups were later challenged with a field strain of M. bovis. The results of the IFN-gamma response, serum antibody levels, M. bovis culture, TB lesion scores, and the expression of C3 and MUT genes were compared between these four groups. The results suggested that vaccination with heat-inactivated M. bovis or BCG protect wild boar from TB. These results also encouraged testing combinations of BCG and inactivated M. bovis to vaccinate wild boar against TB. Vaccine formulations using heat-inactivated M. bovis for TB control in wildlife would have the advantage of being environmentally safe and more stable under field conditions when compared to live BCG vaccines. The antibody response and MUT expression levels can help differentiating between vaccinated and infected wild boar and as correlates of protective response in vaccinated animals. These results suggest that vaccine studies in free-living wild boar are now possible to reveal the full potential of protecting against TB using oral M. bovis inactivated and BCG vaccines. 相似文献
30.