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The chemiluminescence (CL) reaction of acyclovir (ACV)–potassium permanganate, with formaldehyde as an enhancer, was investigated by the flow‐injection system, and a new method is reported for the determination of ACV on the basis of the reaction. The method is rapid, effective and simple for the determination of acyclovir in the range 0.2–80 mg/L, with a limit of detection of 0.06 mg/L (3 S:N), a relative standard deviation (RSD) of 3.7% for the determination of 1.0 mg/L acyclovir solution in 11 repeated measurements. The method has been applied to the determination of acyclovir in pharmaceuticals, with satisfactory results. The possible reaction mechanism is also discussed briefly. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
224.
Zi Chen Benjamen A. Filas Victor D. Varner Larry A. Taber 《Birth defects research. Part C, Embryo today : reviews》2012,96(2):132-152
In the developing embryo, tissues differentiate, deform, and move in an orchestrated manner to generate various biological shapes driven by the complex interplay between genetic, epigenetic, and environmental factors. Mechanics plays a key role in regulating and controlling morphogenesis, and quantitative models help us understand how various mechanical forces combine to shape the embryo. Models allow for the quantitative, unbiased testing of physical mechanisms, and when used appropriately, can motivate new experimentaldirections. This knowledge benefits biomedical researchers who aim to prevent and treat congenital malformations, as well as engineers working to create replacement tissues in the laboratory. In this review, we first give an overview of fundamental mechanical theories for morphogenesis, and then focus on models for specific processes, including pattern formation, gastrulation, neurulation, organogenesis, and wound healing. The role of mechanical feedback in development is also discussed. Finally, some perspectives aregiven on the emerging challenges in morphomechanics and mechanobiology. Birth Defects Research (Part C) 96:132–152, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
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Yong-Ke You Wei-Feng Wu Xiao-Ru Huang Hai-Di Li Ye-Ping Ren Jin-Cheng Zeng Haiyong Chen Hui Yao Lan 《International journal of biological sciences》2021,17(14):3911
Introduction and Aims: Elevated plasma levels of C-reactive protein (CRP) are closely associated with progressive renal injury in patients with chronic kidney disease (CKD). Here, we tested a hypothesis that CRP may promote renal fibrosis and inflammation via a TGF-β/Smad3-dependent mechanism.Methods: Role and mechanisms of TGF-β/Smad3 in CRP-induced renal fibrosis and inflammation were examined in a mouse model of unilateral ureteral obstruction (UUO) induced in CRP Tg/Smad3 KO mice and in a rat tubular epithelial cell line in which Smad3 gene is stably knocked down (S3KD-NRK52E).Results: We found that mice overexpressing the human CRP gene were largely promoted renal inflammation and fibrosis as evidenced by increasing IL-1β, TNF-α, MCP-1 expression, F4/80+ macrophages infiltration, and marked accumulation of α-smooth muscle actin (α-SMA), collagen I and fibronectin in the UUO kidney, which were blunted when Smad3 gene was deleted in CRPtg-Smad3KO. Mechanistically, we found that the protection of renal inflammation and fibrosis in the UUO kidney of CRPtg-Smad3KO mice was associated with the inactivation of CD32-NF-κB and TGF-β/Smad3 signaling.Conclusion: In conclusion, Smad3 deficiency protects against CRP-mediated renal inflammation and fibrosis in the UUO kidney by inactivating CD32-NF-κB and TGF-β/Smad3 signaling. 相似文献
227.
Hormonal regulation of trehalose metabolism in the blowfly, Phormia regina: interaction between hypertrehalosemic and hypotrehalosemic hormones 总被引:1,自引:0,他引:1
Hypertrehalosemia occurs two days after cardiacectomy of adult male Phormia regina with no attendant change in fat body glycogen. In spite of this, cardiacectomized flies caused to fly for 10 min show a lower rate of haemolymph trehalose turnover, and seem to have a decreased capability for synthesizing trehalose from haemolymph glucose. Phormia brain is shown to contain a hypotrehalosemic hormone whose release depends on the integrity of the stomatogastric nervous system. It is possible that the hypertrehalosemic condition in cardiacectomized flies is a result of the absence of this hormone from the blood. 相似文献
228.
Anla Hu Li Li Chuanlai Hu Daoming Zhang Chen Wang Yan Jiang Meng Zhang Chunmei Liang Wenjun Chen Qingli Bo Qihong Zhao 《Biological trace element research》2018,182(1):21-28
Data on the effects of magnesium-zinc-calcium-vitamin D co-supplementation on hormonal profiles, biomarkers of inflammation, and oxidative stress among women with polycystic ovary syndrome (PCOS) are scarce. The objective of this study was to assess the effects of magnesium-zinc-calcium-vitamin D co-supplementation on hormonal profiles, biomarkers of inflammation, and oxidative stress in women with PCOS. Sixty PCOS women were randomized into two groups and treated with 100 mg magnesium, 4 mg zinc, 400 mg calcium plus 200 IU vitamin D supplements (n = 30), or placebo (n = 30) twice a day for 12 weeks. Hormonal profiles, biomarkers of inflammation, and oxidative stress were assessed at baseline and at end-of-treatment. After the 12-week intervention, compared with the placebo, magnesium-zinc-calcium-vitamin D co-supplementation resulted in significant reductions in hirsutism (?2.4 ± 1.2 vs. ?0.1 ± 0.4, P < 0.001), serum high sensitivity C-reactive protein (?0.7 ± 0.8 vs. +0.2 ± 1.8 mg/L, P < 0.001), and plasma malondialdehyde (?0.4 ± 0.3 vs. +0.2 ± 1.0 μmol/L, P = 0.01), and a significant increase in plasma total antioxidant capacity concentrations (+46.6 ± 66.5 vs. ?7.7 ± 130.1 mmol/L, P = 0.04). We failed to find any significant effect of magnesium-zinc-calcium-vitamin D co-supplementation on free androgen index, and other biomarkers of inflammation and oxidative stress. Overall, magnesium-zinc-calcium-vitamin D co-supplementation for 12 weeks among PCOS women had beneficial effects on hormonal profiles, biomarkers of inflammation, and oxidative stress. 相似文献
229.
Biobased poly(propylene sebacate) as shape memory polymer with tunable switching temperature for potential biomedical applications 总被引:2,自引:0,他引:2
From the point of better biocompatibility and sustainability, biobased shape memory polymers (SMPs) are highly desired. We used 1,3-propanediol, sebacic acid, and itaconic acid, which have been industrially produced via fermentation or extraction with large quantities as the main raw materials for the synthesis of biobased poly(propylene sebacate). Diethylene glycol was used to tailor the flexibility of the polyester. The resulted polyesters were found to be promising SMPs with excellent shape recovery and fixity (near 100% and independent of thermomechanical cycles). The switching temperature and recovery speed of the SMPs are tunable by controlling the composition of the polyesters and their curing extent. The continuously changed switching temperature ranging from 12 to 54 °C was realized. Such temperature range is typical for biomedical applications in the human body. The molecular and crystalline structures were explored to correlate to the shape memory behavior. The combination of potential biocompatibility and biodegradability of the biobased SMPs makes them suitable for fabricating biomedical devices. 相似文献
230.
Lu SC Atangan L Won Kim K Chen MM Komorowski R Chu C Han J Hu S Gu W Véniant M Wang M 《Journal of lipid research》2012,53(4):643-652
The aim of this study is to investigate the capability of an apoA-I mimetic with multiple amphipathic helices to form HDL-like particles in vitro and in vivo. To generate multivalent helices and to track the peptide mimetic, we have constructed a peptibody by fusing two tandem repeats of 4F peptide to the C terminus of a murine IgG Fc fragment. The resultant peptidbody, mFc-2X4F, dose-dependently promoted cholesterol efflux in vitro, and the efflux potency was superior to monomeric 4F peptide. Like apoA-I, mFc-2X4F stabilized ABCA1 in J774A.1 and THP1 cells. The peptibody formed larger HDL particles when incubated with cultured cells compared with those by apoA-I. Interestingly, when administered to mice, mFc-2X4F increased both pre-β and α-1 HDL subfractions. The lipid-bound mFc-2X4F was mostly in the α-1 migrating subfraction. Most importantly, mFc-2X4F and apoA-I were found to coexist in the same HDL particles formed in vivo. These data suggest that the apoA-I mimetic peptibody is capable of mimicking apoA-I to generate HDL particles. The peptibody and apoA-I may work cooperatively to generate larger HDL particles in vivo, either at the cholesterol efflux stage and/or via fusion of HDL particles that were generated by the peptibody and apoA-I individually. 相似文献