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1.
Acta Biomater ; 173: 314-324, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-37949201

ABSTRACT

In-stent restenosis (ISR) after percutaneous coronary intervention is a major reason for limited long-term patency due to complex neointimal proliferation caused by vascular injury. Drug-coated balloon (DCB) has been developed to treat various cardiovascular diseases including ISR by providing anti-proliferative drugs into blood vessel tissues. However, a significant proportion of the drug is lost during balloon tracking, resulting in ineffective drug delivery to the target region. In this study, we report an everolimus-coated balloon (ECB) using everolimus-loaded gelatin-hydroxyphenyl propionic acid microgel (GM) with enhanced everolimus delivery to vascular walls for long-term patency. GM with high drug loading (> 97%) was simply prepared by homogenizing enzyme-mediated crosslinked hydrogels. The optimal condition to prepare GM-coated ECB (GM-ECB) was established by changing homogenization time and ethanol solvent concentration (30 ∼ 80%). In vitro sustained everolimus release for 30 d, and cellular efficacy using smooth muscle cells and vascular endothelial cells were evaluated. Additionally, an in vivo drug transfer levels of GM-ECB using rabbit femoral arteries were assessed with reduced drug loss and efficient drug delivery capability. Finally, using ISR-induced porcine models, effective in vivo vascular patency 4 weeks after treatment of ECBs was also confirmed. Thus, this study strongly demonstrates that GM can be used as a potential drug delivery platform for DCB application. STATEMENT OF SIGNIFICANCE: We report an ECB using everolimus-loaded GM prepared by homogenization of enzymatic cross-linked hydrogel. GM showed efficient drug loading (> 97 %) and controllable size. GM-ECB exhibited potential to deliver everolimus in a sustained manner to target area with drug efficacy and viability against SMC and EC. Although GM-ECB had much lower drug content compared to controls, animal study demonstrated enhanced drug transfer and reduced drug loss of GM-ECB due to the protection of encapsulated drugs by GM, and the possible interaction between GM and endothelium. Finally, vascular patency and safety were assessed using ISR-induced porcine models. We suggest an advanced DCB strategy to alleviate rapid drug clearance by bloodstream while improving drug delivery for a long-term vascular patency.


Subject(s)
Cardiovascular Agents , Coronary Restenosis , Microgels , Animals , Swine , Rabbits , Everolimus/pharmacology , Gelatin , Endothelial Cells , Vascular Patency , Risk Factors , Treatment Outcome , Catheters/adverse effects , Coated Materials, Biocompatible , Coronary Restenosis/etiology , Coronary Restenosis/therapy , Paclitaxel
2.
SAGE Open Med Case Rep ; 11: 2050313X231177108, 2023.
Article in English | MEDLINE | ID: mdl-37274938

ABSTRACT

In a United Nations (UN) staff member headquarters in South Sudan, we present a rare typhoid fever complicated by syncope due to relative bradycardia. A 25-year-old male presented to our hospital with a high fever, diarrhea, and no vomiting. He had no substantial medical background. He was diagnosed with an unspecified digestive disorder and received initial treatment. Two syncope episodes were recorded in the Level 1 hospital. He was referred to our hospital at the 30th hour and the third fainting occurred. Electrocardiogram showed bradycardia with a heart rate of 40 beats/min. The atropine test was negative; the initial diagnosis was sinus sickness syndrome. Microbiology tests later suggested typhoid infection. Then, the diagnosis changed to relative bradycardia caused by Salmonella typhi; and he was orally treated with the third-generation Quinolone antibiotic. He significantly improved and got discharged on the seventh day. In conclusion, typhoid remains a real and present threat to UN staff and civilians in South Sudan.

3.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 12): 1861-1865, 2019 Dec 01.
Article in English | MEDLINE | ID: mdl-31871746

ABSTRACT

In the title compound, C17H21NO4S, the 1,4-di-hydro-pyridine ring has an envelope conformation with the Csp 3 atom at the flap. The thio-phene ring is nearly perpendicular to the best plane through the 1,4-di-hydro-pyridine ring, the dihedral angle being 82.19 (13)°. In the crystal, chains running along the b-axis direction are formed through N-H⋯O inter-actions between the 1,4-di-hydro-pyridine N atom and one of the O atoms of the ester groups. Neighbouring chains are linked by C-H⋯O and C-H⋯π inter-actions. A Hirshfeld surface analysis shows that the most prominent contributuion to the surface contacts are H⋯H contacts (55.1%).

4.
Mol Biol Rep ; 46(2): 2177-2185, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30798487

ABSTRACT

Plant defensins are divided into 18 groups and are multifunctional proteins. The Zea mays defensin 1 (ZmDEF1) gene encodes the defensin 1 protein, which can inhibit alpha-amylase in the insect gut. In this study, the ZmDEF1 gene was transferred into two maize cultivars, LC1 and LVN99, to improve weevil resistance in maize. The recombinant ZmDEF1 protein was assessed for its ability to inhibit alpha-amylase in the gut of the larvae of the maize weevil (Sitophilus zeamais Motsch.). ZmDEF1 was cloned into a pBetaPhaso-dest vector, which harbours phaseolin, a seed-specific promoter, and the Agrobacterium tumefaciens strain C58 harbouring the pBetaPhaso-ZmDEF1 vector was used to transfer the ZmDEF1 gene into two maize cultivars using immature embryos. Transformed calluses were selected on selection media containing kanamycin. The stable integration of the ZmDEF1 transgene into the transgenic maize plant genome was confirmed using Southern blotting. The recombinant ZmDEF1 protein of approximately 10 kDa was expressed in three transgenic maize lines from the LC1 cultivar (C1, C3, and C5) and two transgenic maize lines from the LVN99 cultivar (L1 and L3). The ZmDEF1 transgenic efficiency based on the results of PCR, as well as Southern and Western blotting, was 1.32% and 0.82%, respectively, which depends on the genotypes of LC1 and LVN99. The recombinant ZmDEF1 protein inhibited the alpha-amylase activity of the maize weevil larvae, and its ability to inhibit alpha-amylase is 54.52-63.09% greater than the ZmDEF1 protein extracted from non-transgenic plants.


Subject(s)
Defensins/genetics , Pest Control, Biological/methods , Zea mays/genetics , Agrobacterium tumefaciens/genetics , Animals , Crop Protection/methods , Larva/metabolism , Plants, Genetically Modified/genetics , Seeds/genetics , Transgenes/genetics , Weevils/pathogenicity , Zea mays/metabolism , alpha-Amylases/antagonists & inhibitors
5.
Nano Lett ; 17(6): 3327-3333, 2017 06 14.
Article in English | MEDLINE | ID: mdl-28534635

ABSTRACT

In this paper, the Li4SiO4 nanowires (NWs) were shown to be promising for CO2 capture with ultrafast kinetics. Specifically, the nanowire powders exhibited an uptake of 0.35 g g-1 of CO2 at an ultrafast adsorption rate of 0.22 g g-1 min-1 at 650-700 °C. Lithium silicate (Li4SiO4) nanowires and nanopowders were synthesized using a "solvo-plasma" technique involving plasma oxidation of silicon precursors mixed with lithium hydroxide. The kinetic parameter values (k) extracted from sorption kinetics obtained using NW powders are 1 order of magnitude higher than those previously reported for the Li4SiO4-CO2 reaction system. The time scales for CO2 sorption using nanowires are approximately 3 min and two orders magnitude faster compared to those obtained using lithium silicate powders with spherical morphologies and aggregates. Furthermore, Li4SiO4 nanowire powders showed reversibility through sorption-desorption cycles indicating their suitability for CO2 capture applications. All of the morphologies of Li4SiO4 powders exhibited a double exponential behavior in the adsorption kinetics indicating two distinct time constants for kinetic and the mass transfer limited regimes.

6.
Angew Chem Int Ed Engl ; 56(13): 3645-3649, 2017 03 20.
Article in English | MEDLINE | ID: mdl-28229519

ABSTRACT

Electrochemical conversion of CO2 into energy-dense liquids, such as formic acid, is desirable as a hydrogen carrier and a chemical feedstock. SnOx is one of the few catalysts that reduce CO2 into formic acid with high selectivity but at high overpotential and low current density. We show that an electrochemically reduced SnO2 porous nanowire catalyst (Sn-pNWs) with a high density of grain boundaries (GBs) exhibits an energy conversion efficiency of CO2 -into-HCOOH higher than analogous catalysts. HCOOH formation begins at lower overpotential (350 mV) and reaches a steady Faradaic efficiency of ca. 80 % at only -0.8 V vs. RHE. A comparison with commercial SnO2 nanoparticles confirms that the improved CO2 reduction performance of Sn-pNWs is due to the density of GBs within the porous structure, which introduce new catalytically active sites. Produced with a scalable plasma synthesis technology, the catalysts have potential for application in the CO2 conversion industry.

7.
Cell Biol Int ; 34(7): 769-75, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20402666

ABSTRACT

The effect of GS (ginsenosides) on proliferation of chicken GCs (granulosa cells) from prehierarchical SYF (small yellow follicles) was evaluated, and involvement of the PKC (protein kinase C) signalling pathway as well as mRNA expression of cyclins and CDK (cyclin-dependent kinase) were investigated. Whole SYF or GCs isolated from SYF were cultured in Medium 199 supplemented with 0.5% FCS (fetal calf serum). After 16 h, the cells were challenged with GS alone or in combination with PKC inhibitor H7 or activator PMA (phorbol 12-myristate 13-acetate) for 24 h in serum-free medium. Results showed that in both whole follicles and pure GCs monolayer culture system, GS (0.1-10 microg/ml) significantly increased the number of GCs in SYF in a dose-dependent manner, and this stimulatory effect was inhibited by H7, but enhanced by PMA. Meanwhile, the PCNA-LI (proliferating cell nuclear antigen labelling index) of GCs displayed similar changes with the cell number. Mechanism of GS action was further evaluated in cultured GCs separated from SYF. Western blot analysis showed that 10 microg/ml GS increased PKC translocation from cytoplasm to the plasma membrane of the GCs to become the active state. This effect was blocked by H7. Furthermore, GS up-regulated the expression of cyclin D1/CDK6 and cyclin E/CDK2 mRNAs in GCs; however, inhibition of PKC with H7 attenuated this stimulatory effect. These results indicated that GS could stimulate proliferation of chicken GCs through activated PKC-involved up-regulation of cyclin D1/CDK6 and cyclin E/CDK2 genes, subsequently promoting development of the chicken prehierarchical follicles.


Subject(s)
Cell Proliferation/drug effects , Cyclins/genetics , Gene Expression Regulation, Developmental/drug effects , Ginsenosides/pharmacology , Granulosa Cells/physiology , Ovarian Follicle/cytology , Protein Kinase C/metabolism , Animals , Cell Cycle/physiology , Cells, Cultured , Chickens , Cyclins/metabolism , Enzyme Activation , Female , Granulosa Cells/cytology , Granulosa Cells/drug effects , Ovarian Follicle/drug effects
8.
Prostaglandins Other Lipid Mediat ; 83(4): 285-94, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17499748

ABSTRACT

The interactive actions of prostaglandin (PG) and epidermal growth factor (EGF) on proliferation of granulosa cells was investigated in prehierarchical small yellow follicles (SYF) of laying hens. The granulosa layers were dispersed into single cells by 12.5 microg/ml collagenase. After 16 h pre-incubation in 0.5% fetal calf serum-supplemented medium, the medium was replaced with serum-free medium. Immunocytochemical staining showed that granulosa cells expressed EGF and its receptor, and their expression was increased by PGE(1) (1-100 ng/ml) or forskolin (10(-7) to 10(-5)M) treatments. EGF receptor was also induced by its ligand EGF. The specific prostaglandin synthase inhibitors SC560 (for COX-1) and NS398 (for COX-2) suppressed EGF-stimulated increase of the granulosa cell number. Furthermore, the effect of EGF was confirmed by the immunocytochemical staining of the proliferating cell nuclear antigen in granulosa cells. Though EGF promoted the expression of both COX-1 and COX-2, the rescue experiment indicated that combined treatment of PGE(1) showed better rescuing effect on NS398 inhibition than SC560 at 10(-6)M, which implies COX-2 plays the predominant role in mediating EGF action. The above results indicate that reciprocal stimulation of intracellular PG and EGF production may enhance proliferation of granulosa cells, hence to facilitate development of chicken prehierarchical follicles.


Subject(s)
Cell Proliferation/drug effects , Epidermal Growth Factor/pharmacology , Granulosa Cells/drug effects , Prostaglandins/pharmacology , Animals , Cells, Cultured , Chickens , Cyclooxygenase 1/metabolism , Cyclooxygenase 2/metabolism , Cyclooxygenase Inhibitors/pharmacology , Dose-Response Relationship, Drug , ErbB Receptors/metabolism , Female , Granulosa Cells/cytology , Granulosa Cells/metabolism , Immunohistochemistry , Nitrobenzenes/pharmacology , Ovarian Follicle/cytology , Ovarian Follicle/drug effects , Ovarian Follicle/metabolism , Proliferating Cell Nuclear Antigen/analysis , Pyrazoles/pharmacology , Sulfonamides/pharmacology
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