A Transformable and Bulky Methacrylate Monomer That Enables the Synthesis of an MMA-nBA Alternating Copolymer: Sequence-Dependent Self-Healing Properties.

In this study, we designed a methacrylate molecule with an alkyl-substituted trichloro salicylic acid pendant as a transformable bulky monomer to enable the synthesis of an alternating copolymer of methyl methacrylate (MMA) and n-butyl acrylate (nBA). The adamantyl-substituted methacrylate monomer (1-Ad) showed very low homopolymerization propensity in radical polymerizations, but afforded the alternating copolymer with nBA via copolymerization. The 1-Ad units in the resultant copolymer were quantitatively and selectively transformed into MMA via transesterification with methanol to yield the alternating copolymer of MMA and nBA. Its alternating sequence was clearly demonstrated by a structural analysis via 13 C NMR spectroscopy as well as the low reactivity ratios for the 1-Ad and nBA pair. Finally, we verified the superior self-healing ability of the alternating copolymer compared to that of the corresponding 1 : 1 statistical copolymer.

Synergetic improvement in the mechanical properties of polyurethanes with movable crosslinking and hydrogen bonds.

Polyurethane (PU) materials with movable crosslinking were prepared by a typical two-step synthetic process using an acetylated γ-cyclodextrin (TAcγCD) diol compound. The soft segment of PU is polytetrahydrofuran (PTHF), and the hard segment consists of hexamethylene diisocyanate (HDI) and 1,3-propylene glycol (POD). The synthesized PU materials exhibited the typical mechanical characteristics of a movable crosslinking network, and the presence of hydrogen bonds from the urethane bonds resulted in a synergistic effect. Two kinds of noncovalent bond crosslinking increased the Young's modulus of the material without affecting its toughness. Fourier transform infrared spectroscopy and X-ray scattering measurements were performed to analyze the effect of introducing movable crosslinking on the internal hydrogen bond and the microphase separation structure of PU, and the results showed that the carbonyl groups on TAcγCD could form hydrogen bonds with the PU chains and that the introduction of movable crosslinking weakened the hydrogen bonds between the hard segments of PU. When stretched, the movable crosslinking of the PU materials suppressed the orientation of polymer chains (shish-kebab orientation) in the tensile direction. The mechanical properties of the movable crosslinked PU materials show promise for future application in the industrial field.

Clinical value of microRNA-378a-3p in sepsis and its role in sepsis-induced inflammation and cardiac dysfunction.

This study explored the clinical meaning of miR-378a-3p in sepsis and its influence on sepsis-induced inflammation and cardiac dysfunction. Serum levels of miR-378a-3p were detected by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR). The Receiver Operating Characteristic (ROC) curve was used to evaluate its diagnostic value. The effects of miR-378a-3p on inflammation and cardiac function were evaluated by monitoring left ventricular systolic pressure (LVSP), left ventricular and end-diastolic pressure (LVEDP), maximum rate of change in left ventricular pressure (± dp/dtmax) and detecting the levels of troponin I (cTnI), creatine kinase isoenzyme MB (CK-MB), tumor necrosis factor-a (TNF-a), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß) via enzyme linked immunosorbent assay (ELISA). Serum miR-378a-3p was increased in sepsis patients and rat model. ROC curve indicated that miR-378a-3p might have diagnostic significance for sepsis miR-378a-3p antagomir improved the cardiac function by upregulating the levels of LVSP and ± dp/dtmax, and decreasing the levels of LVEDP, cTnI and CK-MB in rat model. miR-378a-3p antagomir also significantly alleviated the inflammatory responseby down-regulating the expression of TNF-a, IL-6, and IL-1ß. Besides, logistics regression analysis illustrated that miR-378a-3p was an independent influencing factor for the onset of cardiac dysfunction in sepsis. miR-378a-3p has the potential as a diagnostic biomarker for sepsis and decreasing the level of miR-378a-3p had the ability to ameliorate cardiac dysfunction and inflammatory response caused by sepsis.

Self-Healing Thermoplastic Polyurethane Linked via Host-Guest Interactions.

High toughness with self-healing ability has become the ultimate goal in materials research. Herein, thermoplastic polyurethane (TPU) was linked via host-guest (HG) interactions to increase its mechanical properties and self-healing ability. TPU linked via HG interactions was prepared by the step-growth bulk polymerization of hexamethylene diisocyanate (HDI), tetraethylene glycol (TEG), and HG interactions between permethylated amino ßCD (PMeAmßCD) and adamantane amine (AdAm). TPU linked with 10 mol% of HG interactions (HG(10)) showed the highest rupture stress and fracture energy (GF) of 11 MPa and 25 MJ·m-3, which are almost 40-fold and 1500-fold, respectively, higher than those of non-functionalized TEG-based TPU (PU). Additionally, damaged HG(10) shows 87% recovery after heated for 7 min at 80 °C, and completely cut HG(10) shows 80% recovery after 60 min of reattachment at same temperature. The HG interactions in TPU are an important factor in stress dispersion, increasing both its mechanical and self-healing properties. The TPU linked via HG interactions has great promise for use in industrial materials in the near future.

Effects of blood glucose, blood lipids and blood pressure control on recovery of patients with gastric cancer complicated with metabolic syndrome after radical gastrectomy.

This study aimed to investigate the effects of blood glucose, blood lipids and blood pressure control on recovery of patients with gastric cancer complicated with metabolic syndrome (MS) after radical gastrectomy. A total of 150 patients with gastric cancer, who were treated in Daqing Longnan Hospital from November, 2015 to May, 2017, were enrolled in this study. The patients were divided into the MS group (80 cases) and non-MS group (70 cases). Patients in the MS group were given corresponding drugs to control blood pressure, blood lipids and blood glucose, while patients in the non-MS group were not treated with those drugs. Patients in the MS group were divided into the normal and abnormal groups according to the levels of blood glucose, blood lipids and blood pressure. Moreover, occurrences of complications were compared between the normal and abnormal groups. Before surgery, blood glucose, blood lipids and blood pressure in the MS group were significantly higher than those in the non-MS group (p<0.05). One month after operation, blood glucose, blood lipids and blood pressure of the MS group decreased significantly compared to those before operation (p<0.05). Incidence of complications at 1 and 3 months after operation was significantly lower in the normal groups than that in the corresponding abnormal groups (p<0.05). Postoperative recovery was significantly better in the normal groups than that in the corresponding abnormal groups (p<0.05). Logistic regression analysis showed that the incidence of postoperative complications was related to fasting blood glucose, 2 h postprandial blood glucose, glycosylated hemoglobin, total triglycerides (TGs), LDL, mean blood pressure and BMI (p<0.05). The results show that, control of blood glucose, blood lipids and blood pressure in patients with gastric cancer complicated with MS after radical gastrectomy can reduce the incidence of postoperative complications and promote postoperative recovery.