1. |
- Tian, Xiaohe, et al.
(författare)
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Probe for simultaneous membrane and nucleus labeling in living cells and in vivo bioimaging using a two-photon absorption water-soluble Zn(II) terpyridine complex with a reduced pi-conjugation system
- 2017
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Ingår i: Chemical Science. - : ROYAL SOC CHEMISTRY. - 2041-6520 .- 2041-6539. ; 8:1, s. 142-149
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Tidskriftsartikel (refereegranskat)abstract
- Small, biocompatible and water-soluble molecules with high two-photon absorption (2PA) cross-section values (delta) are in high demand for specific bioimaging applications. Here, two novel terpyridine derivative ligands with donor-acceptor (D-A) (L1) and donor-pi-acceptor (D-pi-A) (L2) models, and their corresponding Zn(II) complexes are designed and characterized. It was found that the two-photon absorption cross section values (d) in the near-infrared region (NIR, about 800 nm) are significantly enhanced for complexes 1 and 2 compared to their free D-A type ligand L1, while those of complexes 3 and 4 were greatly decreased relative to their free ligand L2, thus confirming that the smaller ligand (D-A type) displays a suitable Turn-ON fluorescence pair for two-photon fluorescence microscopy (2PFM). Firstly, the potential of simultaneously labeling a live cell plasma membrane and nucleus using complex 1 is demonstrated. In addition, live larval and adult zebrafish incubated with an optimal concentration of 1 demonstrated clear brain uptake. Lastly and importantly, using such a probe to visualize the blood-brain- barrier (BBB) capillary endothelial cells and penetrate the BBB into the central nervous system (CNS) intravenously in a mouse model is also explored.
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2. |
- Li, Jingwen, et al.
(författare)
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Nisin electroadsorption-enabled multifunctional bacterial cellulose membranes for highly efficient removal of organic and microbial pollutants in water
- 2022
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Ingår i: Chemical Engineering Journal. - : Elsevier BV. - 1385-8947 .- 1873-3212. ; 440, s. 135922-
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Tidskriftsartikel (refereegranskat)abstract
- Membranes fabricated from bacteria-produced cellulose have many practical and technological advantages over other means of cellulose fiber production, however, their functionality for targeted applications is limited and requires complex, multi-stage processing, while the mechanisms underpinned the optimum improvements remain largely unknown. Focusing on one of the highest-demand applications in wastewater treatment, here we resolve the three persistent issues in bacterial cellulose membranes (BCMs), namely poor fibrillar network quality, insufficient functionality and unsatisfactory performance, and discover the counterintuitive, yet most effective mechanism of imparting the multifunctional properties. First, innovative application of the Hestrin-Shramm medium instead of the CM0986 medium stimulated Taonella mepensis to produce BCMs with higher yields, more uniform fibrils and developed fibrillar networks, higher crystallinity indexes, better mechanical and thermal properties. Second, a novel but facile electroadsorption method was developed to enhance BCM functionality via bonding a natural bactericidal peptide-Nisin to the deliberately activated terminals on the BCM surface, achieving great antibacterial activity, good durability, well-preserved nanoporous network, outstanding water retention and low toxicity. Third, due to the synergetic effects of surface adsorption, ionic bonding, physical retention and active microbial killing, the Nisin-decorated BCMs enabled outstanding organic dye removal and excellent disinfection performance, among the best in the available reports. Collectively, this study demonstrates that electroadsorption is a promising and potentially generic strategy to fabricate Nisin-decorated and functionalized BCMs for next-generation membrane filters toward water purification.
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3. |
- Wang, Tao, et al.
(författare)
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The benefit of taxane-based therapies over fluoropyrimidine plus platinum (FP) in the treatment of esophageal cancer : a meta-analysis of clinical studies
- 2019
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Ingår i: Drug Design, Development and Therapy. - 1177-8881. ; 13, s. 539-553
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Fluoropyrimidine plus platinum (FP) is currently the standard treatment for esophageal cancer (EC). In recent years, taxane-based chemotherapy has also been used and has shown good efficacy in EC. This study aims to investigate the advantages of taxane-based over FP chemotherapy, as well as discuss its drawbacks, in the treatment of EC. Patients and methods: A literature search was done for studies comparing clinical outcomes between taxane-based and FP chemotherapy in EC. Pooled analyses were performed to compare the efficacy and grade 3/4 adverse events in patients who received neoadjuvant chemotherapy (NACT), neoadjuvant chemoradiotherapy (NACRT), or definitive chemoradiotherapy (dCRT). Subgroup analyses were also conducted in esophageal squamous cell carcinoma (ESCC). Results: Thirty-one studies with a total of 3,912 patients were included in the analysis. Better long-term survival was found in patients who received taxane-based NACT (progression-free survival (PFS): pooled HR=0.58, P=0.0008; and overall survival (OS): pooled HR=0.50, P<0.00001) and dCRT (PFS: pooled HR=0.75, P<0.0001). In NACRT, taxane-based treatment and FP showed similar efficacy. In ESCC patients, taxane-based treatment showed better OS (NACT: pooled HR=0.57, P=0.02; NACRT: pooled HR=0.51, P=0.03; and dCRT: pooled HR=0.73, P<0.0001) than FP chemotherapy. Furthermore, taxane-based therapy also showed a better short-term response (complete response (CR), objective response rate (ORR), disease control rate (DCR), or pathologic complete response (pCR). However, taxane-based therapy was significantly correlated with a higher incidence of grade 3/4 leukopenia, neutropenia, and diarrhea. Conclusion: Compared to FP, taxane-based therapy produced better clinical response and outcomes in EC patients receiving NACT or dCRT, and in all types of therapy in patients with ESCC. Taxane-based treatment is associated with more frequent toxicity.
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4. |
- Yao, Qiuyu, et al.
(författare)
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The vasodilatory effect of sulfur dioxide via SGC/cGMP/PKG pathway in association with sulfhydryl-dependent dimerization
- 2016
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Ingår i: American Journal of Physiology. Regulatory Integrative and Comparative Physiology. - : AMER PHYSIOLOGICAL SOC. - 0363-6119 .- 1522-1490. ; 310:11, s. R1073-R1080
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Tidskriftsartikel (refereegranskat)abstract
- The present study was designed to explore the role of soluble guanylate cyclase (sGC)/cyclic guanosine monophosphate (cGMP)/PKG pathway in sulfur dioxide (SO2)-induced vasodilation. We showed that SO2 induced a concentration-dependent relaxation of phenylephrine (PE)precontracted rat aortic rings in association with an increase in cGMP concentration, whereas L-aspartic acid beta-hydroxamate (HDX), an inhibitor of SO2 synthase, contracted rings in a dose-dependent manner. Pretreatment of aortic rings with the sGC inhibitor ODQ (30 mu M) attenuated the vasodilatory effects of SO2, suggesting the involvement of cGMP pathway in SO2-induced vasodilation. Mechanistically, SO2 upregulated the protein levels of sGC and PKG dimers, while HDX inhibited it, indicating SO2 could promote cGMP synthesis through sGC activation. Furthermore, the dimerization of sGC and PKG and vasodilation induced by SO2 in precontracted rings were significantly prevented by thiol reductants dithiothreitol (DTT). In addition, SO2 reduced the activity of phosphodiesterase type 5 (PDE5), a cGMP-specific hydrolytic enzyme, implying that SO2 elevated cGMP concentration by inhibiting its hydrolysis. Hence, SO2 exerted its vasodilatory effects at least partly by promoting disulfide-dependent dimerization of sGC and PKG, resulting in an activated sGC/cGMP/PKG pathway in blood vessels. These findings revealed a new mode of action and mechanisms by which SO2 regulated the vascular tone.
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5. |
- Zhu, Mingzhu, et al.
(författare)
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L-Cystathionine Inhibits the Mitochondria-Mediated Macrophage Apoptosis Induced by Oxidized Low Density Lipoprotein
- 2014
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Ingår i: International Journal of Molecular Sciences. - : MDPI. - 1661-6596 .- 1422-0067. ; 15:12, s. 23059-23073
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Tidskriftsartikel (refereegranskat)abstract
- This study was designed to investigate the regulatory role of L-cystathionine in human macrophage apoptosis induced by oxidized low density lipoprotein (ox-LDL) and its possible mechanisms. THP-1 cells were induced with phorbol 12-myristate 13-acetate (PMA) and differentiated into macrophages. Macrophages were incubated with ox-LDL after pretreatment with L-cystathionine. Superoxide anion, apoptosis, mitochondrial membrane potential, and mitochondrial permeability transition pore (MPTP) opening were examined. Caspase-9 activities and expression of cleaved caspase-3 were measured. The results showed that compared with control group, ox-LDL treatment significantly promoted superoxide anion generation, release of cytochrome c (cytc) from mitochondrion into cytoplasm, caspase-9 activities, cleavage of caspase-3, and cell apoptosis, in addition to reduced mitochondrial membrane potential as well as increased MPTP opening. However, 0.3 and 1.0 mmol/L L-cystathionine significantly reduced superoxide anion generation, increased mitochondrial membrane potential, and markedly decreased MPTP opening in ox-LDL + L-cystathionine macrophages. Moreover, compared to ox-LDL treated-cells, release of cytc from mitochondrion into cytoplasm, caspase-9 activities, cleavage of caspase-3, and apoptosis levels in L-cystathionine pretreated cells were profoundly attenuated. Taken together, our results suggested that L-cystathionine could antagonize mitochondria-mediated human macrophage apoptosis induced by ox-LDL via inhibition of cytc release and caspase activation.
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