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In this paper, we prove that the ratio of the modulus of the iterates of two points in an escaping Fatou component could be bounded even if the orbit of the component contains a sequence of annuli whose moduli tend to infinity, and this cannot happen when the maximal modulus of the meromorphic function is uniformly large enough. In this way we extend certain related results for entire functions to meromorphic functions with infinitely many poles. [ABSTRACT FROM AUTHOR]

Inflammation and metabolic disorders are crucial factors that induce type 2 diabetes mellitus (T2DM). Lophatherum gracile Brongn. (L. gracile) has been popularly consumed as folk medicine and dietary supplement for the treatment of fever and inflammatory-associated diseases. Flavonoids are the major constituents of L. gracile with various pharmacological effects. However, the protective effects of flavonoids from leaves of L. gracile against T2DM, as well as the potential mechanisms, were not yet elucidated. In the present study, the total flavonoid content of L. gracile (LGBF) with higher flavonoid content and pancreas lipase inhibitory activity was extracted and screened from the leaves of L. gracile. Twelve flavonoid compounds were identified in LGBF by liquid LC-MS analysis. Network pharmacology identified seven potential flavonoid compounds and 10 core targets associated with T2DM. GO and KEGG pathway enrichment analysis indicated that PI3K/AKT and inflammation-related pathways might occupy core status. Molecular docking results showed that the active constituents of LGBF had a good binding activity with key targets. Furthermore, high-fat diet (HFD) and streptozotocin (STZ)-induced diabetic mice were developed and treated with LGBF for experimental validation. The data showed that LGBF intervention potently improved the lipid profiles and insulin sensitivity of HFD and STZ-induced mice. Hepatic inflammation and lipid accumulation were also partially reversed by LGBF intervention. Further assays confirmed that LGBF administration significantly increased PI3K and AKT phosphorylation, while reducing IL-1β expression and NF-κB P65 phosphorylation in the liver of mice. In conclusion, LGBF administration could relieve liver damage in diabetic mice via regulating PI3K/AKT and NF-κB pathways. [ABSTRACT FROM AUTHOR]

Autophagy is one of the underlying causes of resistance to many antitumor drugs, including cisplatin (DDP). The low‐density lipoprotein receptor (LDLR) is a regulator of ovarian cancer (OC) progression. However, whether LDLR regulates DDP resistance in OC via autophagy‐related pathways remains unclear. LDLR expression was measured by quantitative real‐time PCR, western blot (WB) and IHC staining. A Cell Counting Kit 8 assay was employed to evaluate DDP resistance and cell viability, and flow cytometry was used to assess apoptosis. WB analysis was employed to evaluate the expression of autophagy‐related proteins and PI3K/AKT/mTOR signaling pathway proteins. The autophagolysosomes and the fluorescence intensity of LC3 were observed by transmission electron microscopy and immunofluorescence staining, respectively. A xenograft tumor model was established to explore the role of LDLR in vivo. LDLR was highly expressed in OC cells, which was correlated with disease progression. In DDP‐resistant OC cells, high LDLR expression was related to DDP resistance and autophagy. Downregulation of LDLR repressed autophagy and growth in DDP‐resistant OC cell lines by activating the PI3K/AKT/mTOR pathway, and these effects were eliminated by an mTOR inhibitor. In addition, LDLR knockdown also reduced OC tumor growth by suppressing autophagy associated with the PI3K/AKT/mTOR pathway. LDLR promoted autophagy‐mediated DDP resistance in OC associated with the PI3K/AKT/mTOR pathway, indicating that LDLR might be a new target to prevent DDP resistance in OC patients. [ABSTRACT FROM AUTHOR]

Since the halo orbits in the vicinity of the collinear libration points have a strong hyperbolic character, it is possible to use their stable manifold for the transfer from the Earth. However, for halo orbits of small amplitude, the stable manifold could not approach the Earth, direct transfer from the parking orbit around the earth to the stable manifold is impossible. Nevertheless, with a halo orbit insertion maneuver, the perturbed manifold could approach the earth. This paper proposes a method that combines the differential correction method and the genetic algorithm to minimize the halo orbit insertion maneuver velocity. The method takes advantage of both the global convergence behavior of the genetic algorithm and the quick local convergence behavior of the differential correction method. Numerical simulation shows that the method has a good convergence behavior.

The synthesis of a series of novel C2 symmetrical chiral ketones and their activities in catalytic asymmetric epoxidations are described. The first cyclic ketone obtained from the process acted as the ideal template for the introduction of chiral elements. Results also showed that the ester groups that provide rigid and C2 symmetric structures to the cyclic ketones significantly influence the effectiveness of asymmetric epoxidations.