30 research outputs found

    Biology of a leaf miner (Coleoptera) on Liaoningocladus boii (Coniferales) from the Early Cretaceous of northeastern China and the leaf-mining biology of possible insect culprit clades

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    Specimens of the broad-leaved conifer, Liaoningocladus boii Sun, Zheng & Mei 2000 were evaluated from the mid Early Cretaceous Yixian Formation occurring overwhelmingly at Dawangzhangzi, Liaoning Province, NE China. Arthropod-mediated plant damage types (DTs) were categorized for 343 specimens of this host; one of these DTs represented a distinctive leaf-mine, DT280, established as Fossafolia offae Ding, Labandeira & Ren, ichnogen. et ichnosp. nov. A comparison of DT280 to analogous modern leaf mines was based on: (1) leaf-mine features observed in modern leaf mines; (2) likelihood of a particular leaf-mine culprit lineage being present, given phylogenetic evidence; and (3) body fossils of the candidate culprit occurring in the same or a spatiotemporally proximal deposit. Evidence from these three and other sources of information indicate the most likely miner of F. offae was an extinct species of Buprestidae (Coleoptera), perhaps similar to modern leaf-mining tribe Trachyini. Much less likely affiliations were Mordellidae, Chrysomelidae and Curculionoidea. Fossafolia offae leaf mines were produced by a larva that consisted of four instars, engaged in full-depth tissue feeding, partitioned into a linear, earlier-phase mine with a distinctive frass trail and a more blotch-like, later-phase mine. Adults of this leaf miner likely fed on L. boii, producing linear patches of intercostal window feeding, assigned to DT103, or less likely, may have been a pollinator. The adult female likely laid eggs singly into leaf tissues between adjacent major veins, resulting in DT101 ovipositional damage. This study provides for the use of multiple damage-types to document life-history feeding traits for a single herbivore species. Consequently, we introduce the damage-type suite concept to refer to two or more different damage types genetically linked to the same culprit herbivore that issue from different developmental stages (larvae, adult), or are produced by different tissue-penetrating insect organs (ovipositors, mouthparts). In addition, we provide a basis for using three types of general evidence necessary to elucidate identification of the culprit

    Corneal Sub-Basal Nerve Plexus Regeneration Pattern following Implantable Collamer Lens Implantation for Myopia: A Prospective Longitudinal In Vivo Confocal Microscopy Study

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    Implantable Collamer Lens (ICL) surgery has increasingly been adopted for myopia correction in recent decades. This study, employing in vivo confocal microscopy (IVCM), aimed to assess the impact of corneal incision during ICL surgery on the corneal sub-basal nerve plexus (SNP) and adjacent immune dendritiform cells (DCs). In this longitudinal study, eyes from 53 patients undergoing ICL surgery were assessed preoperatively and postoperatively over a twelve-month period. Quantification of seven SNP parameters was performed using ACCMetrics V.2 software. Ultimately, the final analysis was restricted to one eye from each of the 37 patients who completed a minimum of three months’ postoperative follow-up. Preoperative investigations revealed a positive correlation of DC density with patient age and a negative association with corneal nerve fiber density (CNFD). Additionally, both DCs and CNFD were positively linked to spherical equivalent refraction (SER) and inversely related to axial length (AL). Intriguingly, preoperative DC density demonstrated an indirect relationship with both baseline and postoperative CNFD changes. Post-surgery, an initial surge in DC density was observed, which normalized subsequently. Meanwhile, parameters like CNFD, corneal nerve fiber length (CNFL), and corneal nerve fractal dimension (CNFrD) initially showed a decline following surgery. However, at one-year follow-up, CNFL and CNFrD displayed significant recovery, while CNFD did not return to its baseline level. This study thus delineates the regeneration pattern of SNP and alterations in DC density post-ICL surgery, highlighting that CNFD in the central cornea does not completely revert to preoperative levels within a year. Given these findings, practitioners are advised to exercise caution in older patients, those with high myopia, or elevated preoperative DCs who may undergo delayed SNP regeneration

    Histone deacetylase inhibitor 2-hexyl-4-pentynoic acid enhances hydroxyurea therapeutic effect in triple-negative breast cancer cells

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    Triple-negative breast cancer (TNBC) treatment has only limited effect, and it causes a significant number of deaths. Histone deacetylase inhibitors (HDACis) are emerging as promising anti-tumor agents in many types of cancers. We thus hypothesized that 2-hexyl-4-pentynoic acid (HPTA), a novel HDACi, could sensitize TNBC to hydroxyurea (HU, a ribonucleotide reductase inhibitor). In the present study, we investigated the effect of HPTA, alone or in combination with HU on cell survival, DNA double-strand breaks (DSBs), key homologous recombination (HR) repair proteins and cell cycle progression in MDA-MB-468 and MDA-MB-231 human TNBC cell lines. HPTA and HU synergistically inhibited the survival of TNBC cell lines and resulted in the accumulation of DNA double-strand breaks (DSBs). HPTA can sensitize TNBC cells to HU by inhibiting replication protein A2 (RPA2) hyperphosphorylation-mediated HR repair, and lessen cell accumulation in S-phase by inhibiting ATR-CHK1 signaling pathway. Taken together, our data suggested that HPTA enhances HU therapeutic effect by blocking the HR repair and regulating cell cycle progression in TNBC

    Theoretical Prediction of Structural, Mechanical, and Thermophysical Properties of the Precipitates in 2xxx Series Aluminum Alloy

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    We presented a theoretical study for the structural, mechanical, and thermophysical properties of the precipitates in 2xxx series aluminum alloy by applying the widely used density functional theory of Perdew-Burke-Ernzerhof (PBE). The results indicated that the most thermodynamically stable structure refers to the Al3Zr phase in regardless of its different polymorphs, while the formation enthalpy of Al5Cu2Mg8Si6 is only -0.02 eV (close to zero) indicating its metastable nature. The universal anisotropy index of AU follows the trend of: Al2Cu > Al2CuMg ≈ Al3Zr_D022 ≈ Al20Cu2Mn3 > Al3Fe ≈ Al6Mn > Al3Zr_D023 ≈ Al3Zr_L12 > Al7Cu2Fe > Al3Fe2Si. The thermal expansion coefficients (TECs) were calculated based on Quasi harmonic approximation (QHA); Al2CuMg shows the highest linear thermal expansion coefficient (LTEC), followed by Al3Fe, Al2Cu, Al3Zr_L12 and others, while Al3Zr_D022 is the lowest one. The calculated data of three Al3Zr polymorphs follow the order of L12 > D023 > D022, all of them show much lower LTEC than Al substance. For multi-phase aluminum alloys, when the expansion coefficient of the precipitates is quite different from the matrix, it may cause a relatively large internal stress, or even produce cracks under actual service conditions. Therefore, it is necessary to discuss the heat misfit degree during the material design. The discrepancy between a-Al and Al2CuMg is the smallest, which may decrease the heat misfit degree between them and improve the thermal shock resistant behaviors

    Collagen Extracted from Bigeye Tuna (<i>Thunnus obesus</i>) Skin by Isoelectric Precipitation: Physicochemical Properties, Proliferation, and Migration Activities

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    Collagen was extracted from bigeye tuna (Thunnus obesus) skins by salting-out (PSC-SO) and isoelectric precipitation (PSC-IP) methods. The yield of the PSC-IP product was approximately 17.17% (dry weight), which was greater than the yield obtained from PSC-SO (14.14% dry weight). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis indicated that collagen from bigeye tuna skin belongs to collagen type I. Inductively coupled plasma mass spectrometry results indicate that the heavy metal abundance in PSC-IP was lower than the maximum acceptable amounts according to Chinese regulatory standards. In addition, results from a methylthiazolyldiphenyl-tetrazolium bromide assay and an in vitro scratch assay demonstrated that PSC-IP could promote the proliferation and migration of NIH-3T3 fibroblasts. Overall, results suggest PSC-IP could be used to rapidly extract collagen from marine by-products instead of traditional salting-out methods. Collagen from bigeye tuna skin may also have strong potential for cosmetic and biomedical applications

    Green Synthesis of Large-Scale Highly Ordered Core@Shell Nanoporous Au@Ag Nanorod Arrays as Sensitive and Reproducible 3D SERS Substrates

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    We present a simple green synthetic approach to large-scale and highly ordered arrays of vertical nanoporous Au nanorods, with an ultrathin Ag-layer in situ electrodeposited on each nanoporous Au nanorod (denoted as core@shell nanoporous Au@Ag nanorod). As both the nanopores within each nanorod and the gaps between the neighboring nanorods create three-dimensional (3D) “hot spots” homogeneously distributed throughout the whole substrate, the core@shell nanoporous Au@Ag nanorod arrays were proved to be sensitive and reproducible surface-enhanced Raman scattering (SERS) substrates. Not only universal probe molecules (rhodamine 6G, R6G) but also nonadsorbing molecules (polychlorinated biphenyls, PCBs) have been detected by using the substrates. After mono-6-thio-β-cyclodextrin (HS-β-CD) was modified to efficiently capture more PCBs molecules, the detection limit of PCBs was further reduced to 5.35 × 10<sup>–7</sup> M. As a trial of practical application, R6G and PCBs with different molar ratios in their mixed solutions were identified, and two congeners of PCBs in their mixture could also be distinguished, showing great potentials in real-time simultaneous detection of multiple pollutants
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