1,766 research outputs found

    In silico genetic robustness analysis of microRNA secondary structures: potential evidence of congruent evolution in microRNA

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Robustness is a fundamental property of biological systems and is defined as the ability to maintain stable functioning in the face of various perturbations. Understanding how robustness has evolved has become one of the most attractive areas of research for evolutionary biologists, as it is still unclear whether genetic robustness evolved as a direct consequence of natural selection, as an intrinsic property of adaptations, or as congruent correlate of environment robustness. Recent studies have demonstrated that the stem-loop structures of microRNA (miRNA) are tolerant to some structural changes and show thermodynamic stability. We therefore hypothesize that genetic robustness may evolve as a correlated side effect of the evolution for environmental robustness.</p> <p>Results</p> <p>We examine the robustness of 1,082 miRNA genes covering six species. Our data suggest the stem-loop structures of miRNA precursors exhibit a significantly higher level of genetic robustness, which goes beyond the intrinsic robustness of the stem-loop structure and is not a byproduct of the base composition bias. Furthermore, we demonstrate that the phenotype of miRNA buffers against genetic perturbations, and at the same time is also insensitive to environmental perturbations.</p> <p>Conclusion</p> <p>The results suggest that the increased robustness of miRNA stem-loops may result from congruent evolution for environment robustness. Potential applications of our findings are also discussed.</p

    Prevalence of allergic rhinitis among adults in urban and rural areas of China : a population-based cross-sectional survey

    Get PDF
    Purpose: The aim of the present study was to compare the prevalence of self-reported and confirmable allergic rhinitis (AR) with positive skin prick test (SPT) results among adults living in urban and rural areas of China. Methods: Adults from a community in Beijing and a village in Baoding were selected as representative urban and rural dwellers, respectively. All eligible residents were enrolled from the population register and received a face-to-face interview using modified validated questionnaires. Equal sets of randomly selected self-reporting AR-positive and AR-negative participants who responded to the questionnaires were also investigated using skin prick tests. Results: A total of 803 participants in the rural area and a total of 1,499 participants in the urban area completed the questionnaires, with response rates being 75.9% and 81.5% respectively. The prevalence of self-reported AR of the rural area (19.1%) was significantly higher than that of the urban area (13.5%). The elementary school of educational level increased the risk of having AR (adjusted OR=2.198, 95% CI=1.072-2.236). The positive SET rates among subjects with self-reported AR in the rural and urban areas were 32.5% and 53.3%, respectively; the confirmable AR prevalence of 6.2% and 7.2% among the rural and urban adults, respectively. Conclusions: The prevalence of confirmable AR is similar between rural and urban areas in China, although there is a higher prevalence of self-reported AR in the former

    4-(1H-Pyrazol-3-yl)pyridine–terephthalic acid–water (2/1/2)

    Get PDF
    In the title compound, 2C8H7N3·C8H6O4·2H2O, the pyridine and pyrazole rings are approximately coplanar, the dihedral angle between them being 4.69 (9)°. The asymmetric unit consists of half of the terephthalic acid (an inversion centre generates the other half of the mol­ecule), one 4-(1H-pyrazol-3-yl)pyridine (4pp) mol­ecule and one water mol­ecule. In the crystal, two 4pp and one terephthalic acid mol­ecules form a linear three-molecule unit as a result of O—H⋯N hydrogen bonds. These units are further assembled into a three-dimensional network by two types of hydrogen bonds, viz. O—H⋯O and N—H⋯O

    TeMO: Towards Text-Driven 3D Stylization for Multi-Object Meshes

    Full text link
    Recent progress in the text-driven 3D stylization of a single object has been considerably promoted by CLIP-based methods. However, the stylization of multi-object 3D scenes is still impeded in that the image-text pairs used for pre-training CLIP mostly consist of an object. Meanwhile, the local details of multiple objects may be susceptible to omission due to the existing supervision manner primarily relying on coarse-grained contrast of image-text pairs. To overcome these challenges, we present a novel framework, dubbed TeMO, to parse multi-object 3D scenes and edit their styles under the contrast supervision at multiple levels. We first propose a Decoupled Graph Attention (DGA) module to distinguishably reinforce the features of 3D surface points. Particularly, a cross-modal graph is constructed to align the object points accurately and noun phrases decoupled from the 3D mesh and textual description. Then, we develop a Cross-Grained Contrast (CGC) supervision system, where a fine-grained loss between the words in the textual description and the randomly rendered images are constructed to complement the coarse-grained loss. Extensive experiments show that our method can synthesize high-quality stylized content and outperform the existing methods over a wide range of multi-object 3D meshes. Our code and results will be made publicly availabl

    DNMT3a in the hippocampal CA1 is crucial in the acquisition of morphine self‐administration in rats

    Get PDF
    Drug‐reinforced excessive operant responding is one fundamental feature of long-lasting addiction‐like behaviors and relapse in animals. However, the transcriptional regulatory mechanisms responsible for the persistent drug‐specific (not natural rewards) operant behavior are not entirely clear. In this study, we demonstrate a key role for one of the de novo DNA methyltransferase, DNMT3a, in the acquisition of morphine self‐administration (SA) in rats. The expression of DNMT3a in the hippocampal CA1 region but not in the nucleus accumbens shell was significantly up‐regulated after 1‐ and 7‐day morphine SA (0.3 mg/kg/infusion) but not after the yoked morphine injection. On the other hand, saccharin SA did not affect the expression of DNMT3a or DNMT3b. DNMT inhibitor 5‐aza‐2‐deoxycytidine (5‐aza) microinjected into the hippocampal CA1 significantly attenuated the acquisition of morphine SA. Knockdown of DNMT3a also impaired the ability to acquire the morphine SA. Overall, these findings suggest that DNMT3a in the hippocampus plays an important role in the acquisition of morphine SA and may be a valid target to prevent the development of morphine addiction. Includes Supplemental informatio

    Effect of Dihuang rougui decoction on ovariectomyinduced osteoporosis in rats

    Get PDF
    Purpose: To investigate the effect of Dihuang Rougui Decoction (DRD) on ovariectomy-induced osteoporosis in rats.Methods: Female Sprague-Dawley rats were randomly assigned to a  normal group (control) and five ovariectomy (OVX) subgroups: OVX with vehicle (OVX), OVX with positive control drug (alendronate sodium tablets, 1.6 mg/kg/week), and OVX + DRD (75, 150 or 300 mg/kg/day). After the rats were subjected to ovariectomy for 4 weeks, fosamax or DRD were administered daily (orally) for 16 weeks. The bone mineral density (BMD) of the L4 vertebrae and right femurs of the rats was evaluated. Serum hormones estradiol (E2), follicle-stimulating  hormone (FSH) and luteinizing hormone (LH) levels and serum alkaline phosphatase (ALP), osteocalcin (OC) and telopeptides of collagen type I (CTx) levels of the rats were determined. The bone tissue morphology of the rats was examined by microscopy.Results: The results show that DRD dose-dependently inhibited bone  mineral density (BMD) reduction of L4 vertebrae and femurs (both p &lt; 0.05). DRD significantly increased serum E2, FSH and LH levels (p &lt; 0.05) in the osteoporotic rats, and significantly lowered serum ALP, CTx and OC concentrations, compared to OVX group (p &lt; 0.01). Compared with OVX model group, bone trabeculae in all three DRD groups and nilestriol groups were wider, and the space and connections markedly increased. Furthermore, the medullary cavity reduced in size.Conclusion: These findings indicate that DRD mitigates OVX-induced  osteoporosis in rats, and thus, the decoction has a potential for clinical  management of osteoporosis patients.Keywords: Dihuang Rougui decoction, Osteoporosis, Ovariectomy, Bone mineral density, Serum bone marker, Bone tissue morpholog
    corecore