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Absence of the phasmid was demonstrated with the transmission electron microscope in immature third-stage (M3) and fourth-stage (M4) males and mature fifth-stage males (M5) of Heterodera schachtii, M3 and M4 of Verutus volvingentis, and M5 of Cactodera eremica. This absence was supported by the lack of phasmid staining with Coomassie blue and cobalt sulfide. All phasmid structures, except the canal and ampulla, were absent in the postpenetration second-stage juvenile (J2) of H. schachtii. The prepenetration V. volvingentis J2 differs from H. schachtii by having only a canal remnant and no ampulla. This and parsimonious evidence suggest that these two types of phasmids probably evolved in parallel, although ampulla and receptor cavity shape are similar. Absence of the male phasmid throughout development might be associated with an amphimictic mode of reproduction. Phasmid function is discussed, and female pheromone reception ruled out. Variations in ampulla shape are evaluated as phylogenetic character states within the Heteroderinae and putative phylogenetic outgroup Hoplolaimidae. 相似文献
3.
Phylogenetic characters for Heteroderinae Luc. et al., 1988 are evaluated in Meloidodera which is believed to have primarily ancestral characters. Phasmid ultrastructure is observed in second-stage juveniles (J2), third-stage juvenile males, fourth-stage juvenile males, and fifth-stage males of Meloidodera floridensis and M. charis. Phasmid secretion occurs inside the egg before the J1-J2 molt. Before J2 hatch, concentric lamellar membranes occur within the sheath and socket cells. Some membranes become lamellae of the sheath cell plasma membrane; others become multilamellar bodies. During early molting, plasma membrane lamellae disappear and a distal dendrite segment appears in a rudimentary canal. After the molt, the distal dendrite is not present within the canal. The phylogenetic utility of phasmid features is discussed. In both species the ampulla shape and size between molts are stable features in juveniles and males. The posthatch J2 sheath cell receptor cavity may vary in a species specific manner, but comparative morphology requires precise timing after hatch. 相似文献
4.
O. Limaj M. Ortolani V. Giliberti A. Di Gaspare F. Mattioli S. Lupi 《Plasmonics (Norwell, Mass.)》2013,8(2):851-858
We studied surface plasmon sensors based on micrometric metal meshes by optical transmission spectroscopy as a function of the angle of incidence. The mesh period was set to 2 μm for operation at mid-infrared wavelengths. Metal meshes on dielectric substrates were compared to suspended meshes obtained with a lift-off-free fabrication process, which reduces plasmon damping and increases the quality factor up to 25. We have numerically calculated the electric field distribution of “dark” quadrupole-like modes and found that the suspended mesh provides an enhanced interaction volume extending up to hundreds of nanometers in free space. Our sensors have been experimentally tested and they exhibited a sensitivity up to 1.4?·?10?3?nm?1, at least 1 order of magnitude better than standard mid-infrared absorption spectroscopy. 相似文献
5.
Giovanni Astuti Sandro Pratesi Angelino Carta Lorenzo Peruzzi 《Plant Species Biology》2020,35(2):130-137
We found functionally male individuals in an otherwise hermaphroditic population of Tulipa pumila (Liliaceae) located in Tuscany (central Italy). We investigated the sex ratio of this population, followed by morphometric analyses of the scape, leaves and flowers, and tests on pollen germinability and seed number and mass, in order to infer which sexual strategy produced the observed co-occurrence of male and hermaphrodite individuals. We found that sex ratio deviated from 1:1, and functionally male individuals showed a smaller plant size and a reduced pollen fitness (germinability and siring ability) compared to hermaphrodites. These findings point to a resource-dependent sexual allocation strategy, probably associated with gender diphasy. 相似文献
6.
Bonanomi Giuliano Zotti Maurizio Cesarano Gaspare Sarker Tushar C. Saulino Luigi Saracino Antonio Idbella Mohamed Agrelli Diana D’Ascoli Rosaria Rita Angelo Adamo Paola Allevato Emilia 《Plant and Soil》2021,460(1-2):263-280
Plant and Soil - Data about woody debris (WD) decomposition are very scarce for the Mediterranean basin. The specific aim of this work is to explore the relationships between WD traits with the... 相似文献
7.
A potentiated cooperation of carbonic anhydrase IX and histone deacetylase inhibitors against cancer
Jessica Ruzzolini Elena Andreucci Silvia Peppicelli Francesca Bianchini Fabrizio Carta 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):391-397
Abstract The emergence of tumour recurrence and resistance limits the survival rate for most tumour-bearing patients. Only, combination therapies targeting pathways involved in the induction and in the maintenance of cancer growth and progression might potentially result in an enhanced therapeutic efficacy. Herein, we provided a prospective combination treatment that includes suberoylanilide hydroxamic acid (SAHA), a well-known inhibitor of histone deacetylases (HDACs), and SLC-0111, a novel inhibitor of carbonic anhydrase (CA) IX. We proved that HDAC inhibition with SAHA in combination with SLC-0111 affects cell viability and colony forming capability to greater extent than either treatment alone of breast, colorectal and melanoma cancer cells. At the molecular level, this therapeutic regimen resulted in a synergistically increase of histone H4 and p53 acetylation in all tested cell lines. Overall, our findings showed that SAHA and SLC-0111 can be regarded as very attractive combination providing a potential therapeutic strategy against different cancer models. 相似文献
8.
Maria A. De Marco Stefano Porru Paolo Cordioli Bruno M. Cesana Ana Moreno Laura Calzoletti Lebana Bonfanti Arianna Boni Antonio Scotto Di Carlo Cecilia Arici Angela Carta Maria R. Castrucci Isabella Donatelli Paola Tomao Vittoria M. Peri Livia Di Trani Nicoletta Vonesch 《PloS one》2013,8(2)
Background
Pigs play a key epidemiologic role in the ecology of influenza A viruses (IAVs) emerging from animal hosts and transmitted to humans. Between 2008 and 2010, we investigated the health risk of occupational exposure to swine influenza viruses (SIVs) in Italy, during the emergence and spread of the 2009 H1N1 pandemic (H1N1pdm) virus.Methodology/Principal Findings
Serum samples from 123 swine workers (SWs) and 379 control subjects (Cs), not exposed to pig herds, were tested by haemagglutination inhibition (HI) assay against selected SIVs belonging to H1N1 (swH1N1), H1N2 (swH1N2) and H3N2 (swH3N2) subtypes circulating in the study area. Potential cross-reactivity between swine and human IAVs was evaluated by testing sera against recent, pandemic and seasonal, human influenza viruses (H1N1 and H3N2 antigenic subtypes). Samples tested against swH1N1 and H1N1pdm viruses were categorized into sera collected before (n. 84 SWs; n. 234 Cs) and after (n. 39 SWs; n. 145 Cs) the pandemic peak. HI-antibody titers ≥10 were considered positive. In both pre-pandemic and post-pandemic peak subperiods, SWs showed significantly higher swH1N1 seroprevalences when compared with Cs (52.4% vs. 4.7% and 59% vs. 9.7%, respectively). Comparable HI results were obtained against H1N1pdm antigen (58.3% vs. 7.7% and 59% vs. 31.7%, respectively). No differences were found between HI seroreactivity detected in SWs and Cs against swH1N2 (33.3% vs. 40.4%) and swH3N2 (51.2 vs. 55.4%) viruses. These findings indicate the occurrence of swH1N1 transmission from pigs to Italian SWs.Conclusion/Significance
A significant increase of H1N1pdm seroprevalences occurred in the post-pandemic peak subperiod in the Cs (p<0.001) whereas SWs showed no differences between the two subperiods, suggesting a possible occurrence of cross-protective immunity related to previous swH1N1 infections. These data underline the importance of risk assessment and occupational health surveillance activities aimed at early detection and control of SIVs with pandemic potential in humans. 相似文献9.
10.
Castelli MP Ferraro L Mocci I Carta F Carai MA Antonelli T Tanganelli S Cignarella G Gessa GL 《Journal of neurochemistry》2003,87(3):722-732
Two gamma-hydroxybutyric acid (GHB) analogues, trans-gamma-hydroxycrotonic acid (t-HCA) and gamma-(p-methoxybenzyl)-gamma-hydroxybutyric acid (NCS-435) displaced [3H]GHB from GHB receptors with the same affinity as GHB but, unlike GHB, failed to displace [3H]baclofen from GABAB receptors. The effect of the GHB analogues, GHB and baclofen, on G protein activity and hippocampal extracellular glutamate levels was compared. While GHB and baclofen stimulated 5'-O-(3-[35S]thiotriphospate) [35S]GTPgammaS binding both in cortex homogenate and cortical slices, t-HCA and NCS-435 were ineffective up to 1 mm concentration. GHB and baclofen effect was suppressed by the GABAB antagonist CGP 35348 but not by the GHB receptor antagonist NCS-382. Perfused into rat hippocampus, 500 nm and 1 mm GHB increased and decreased extracellular glutamate levels, respectively. GHB stimulation was suppressed by NCS-382, while GHB inhibition by CGP 35348. t-HCA and NCS-435 (0.1-1000 microm) locally perfused into hippocampus increased extracellular glutamate; this effect was inhibited by NCS-382 (10 microm) but not by CGP 35348 (500 microm). The results indicate that GHB-induced G protein activation and reduction of glutamate levels are GABAB-mediated effects, while the increase of glutamate levels is a GHB-mediated effect. Neither t-HCA nor NCS-435 reproduced GHB sedative/hypnotic effect in mice, confirming that this effect is GABAB-mediated. The GHB analogues constitute important tools for understanding the physiological role of endogenous GHB and its receptor. 相似文献