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991.
The major cause of hemodialysis vascular access dysfunction (HVAD) is the occurrence of stenosis followed by thrombosis at venous anastomosis sites due to the aggressive development of venous neointimal hyperplasia. Local delivery of antiproliferative drugs may be effective in inhibiting hyperplasia without causing systemic side effects. We have previously demonstrated that paclitaxel-coated expanded poly(tetrafluoroethylene) (ePTFE) grafts, by a dipping method, could prevent neointimal hyperplasia and stenosis of arteriovenous (AV) hemodialysis grafts, especially at the graft-venous anastomoses; however, large quntities of initial burst release have remained a problem. To achieve controlled drug release, paclitaxel (Ptx)-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (Ptx-PLGA-NPs) were prepared by the emulsion-solvent evaporation method and then transferred to the luminal surface and inner part of ePTFE vascular grafts through our micro tube pumping and spin penetration techniques. Scanning electron microscope (SEM) images of various stages of Ptx-PLGA-NPs unequivocally showed that micro tube pumping followed by spin penetration effectively transferred Ptx-PLGA-NPs to the inner part, as well as the luminal surface, of an ePTFE graft. In addition, the in vitro release profiles of paclitaxel demonstrated that this new system achieved controlled drug delivery with a reduced initial burst release. These results suggest that loading of Ptx-PLGA-NPs to the luminal surface and the inner part of an ePTFE graft is a promising strategy to ultimately inhibit the development of venous neointimal hyperplasia. 相似文献
992.
During in vivo tissue regeneration, cell behavior is highly influenced by the surrounding environment. Thus, the choice of scaffold material and its microstructure is one of the fundamental steps for a successful in vitro culture. An efficacious method for scaffold fabrication should prove its versatility and the possibility of controlling micro- and nanostructure. In this paper, hyaluronic acid 3D scaffolds were developed through lamination of micropatterned membranes, fabricated after optimization of a soft-lithography method. The scaffold presented here is characterized by a homogeneous hexagonal lattice with porosity of 69%, specific surface area of 287 cm-1, and permeability of 18.9 microm2. The control over the geometry was achieved with an accuracy of 20 mum. This technique allowed not only fabrication of planar 3D scaffolds but also production of thin wall tubular constructs. Mechanical tests, performed on dry tubular scaffolds, show high rupture tensile strength. This construct could be promising not only as engineered vascular grafts but also for regeneration of skin, urethra, and intestinal walls. The biocompatibility of a 3D planar scaffold was tested by seeding human fibroblasts. The cells were cultured in both static and dynamic conditions, in a perfusion bioreactor at different flow rates. Microscope analysis and MTT test showed cell proliferation and viability and a uniform cell distribution likely due to an appropriate lattice structure. 相似文献
993.
Barbara Casillas-Prez Christopher D. Pull Filip Naiser Elisabeth Naderlinger Jiri Matas Sylvia Cremer 《Ecology letters》2022,25(1):89-100
Infections early in life can have enduring effects on an organism's development and immunity. In this study, we show that this equally applies to developing ‘superorganisms’––incipient social insect colonies. When we exposed newly mated Lasius niger ant queens to a low pathogen dose, their colonies grew more slowly than controls before winter, but reached similar sizes afterwards. Independent of exposure, queen hibernation survival improved when the ratio of pupae to workers was small. Queens that reared fewer pupae before worker emergence exhibited lower pathogen levels, indicating that high brood rearing efforts interfere with the ability of the queen's immune system to suppress pathogen proliferation. Early-life queen pathogen exposure also improved the immunocompetence of her worker offspring, as demonstrated by challenging the workers to the same pathogen a year later. Transgenerational transfer of the queen's pathogen experience to her workforce can hence durably reduce the disease susceptibility of the whole superorganism. 相似文献
994.
Harańczyk Michał Konieczyńska Małgorzata Płazak Wojciech 《Sleep and biological rhythms》2022,20(1):65-72
Sleep and Biological Rhythms - Obstructive sleep apnea syndrome (OSAS) is considered to be an important predisposing factor for cardiovascular diseases. The main objective of this study was to... 相似文献
995.
996.
Piotr Zabielski Jarosław Daniluk Hady Razak Hady Adam R. Markowski Monika Imierska Jan Górski Agnieszka U. Blachnio-Zabielska 《Journal of cellular physiology》2019,234(2):1851-1861
Liver, as one of the most important organs involved in lipids and glucose metabolism, is perceived as a key tissue for pharmacotherapy of insulin resistance (IRes) and type 2 diabetes. Ceramides (Cer) are biologically active lipids, which accumulation is associated with the induction of muscle IRes. We sought to determine the role of intrahepatic bioactive lipids production on insulin action in liver of insulin-resistant rats and after myriocin administration. The experiments were conducted on male Wistar rats divided into three groups: Control, fed high-fat diet (HFD), and fed HFD and treated with myriocin (HFD/Myr). Before sacrifice, the animals were infused with a [U-13C]palmitate to calculate lipid synthesis rate by means of tracer incorporation technique in particular lipid groups. Liver Cer, diacylglycerols (DAG), acyl-carnitine concentration, and isotopic enrichment were analyzed by LC/MS/MS. Proteins involved in lipid metabolism and insulin pathway were analyzed by western blot analysis. An OGTT and ITT was also performed. HFD-induced IRes and increased both the synthesis rate and the content of DAG and Cer, which was accompanied by inhibition of an insulin pathway. Interestingly, myriocin treatment reduced synthesis rate not only of Cer but also DAG and improved insulin sensitivity. We conclude that the insulin-sensitizing action of myriocin in the liver is a result of the lack of inhibitory effect of lipids on the insulin pathway, due to the reduction of their synthesis rate. This is the first study showing how the synthesis rate of individual lipid groups in liver changes after myriocin administration. 相似文献
997.
Claudia Abbruzzese Silvia Matteoni Michele Persico Barbara Ascione Silvia Schenone Francesca Musumeci Rosario Amato Nicola Perrotti Paola Matarrese Marco G. Paggi 《Journal of cellular physiology》2019,234(12):22529-22542
The small molecule SI113 is an inhibitor of the kinase activity of SGK1, a key biological regulator acting on the PI3K/mTOR signal transduction pathway. Several studies demonstrate that this compound is able to strongly restrain cancer growth in vitro and in vivo, alone or in associative antineoplastic treatments, being able to elicit an autophagic response, either cytotoxic or cytoprotective. To elucidate more exhaustively the molecular mechanisms targeted by SI113, we performed activity-based protein profiling (ABPP) proteomic analysis using a kinase enrichment procedure. This technique allowed the identification via mass spectrometry of novel targets of this compound, most of them involved in functions concerning cell motility and cytoskeletal architecture. Using a glioblastoma multiforme, hepatocarcinoma and colorectal carcinoma cell line, we recognized an inhibitory effect of SI113 on cell migration, invading, and epithelial-to-mesenchymal transition. In addition, these cancer cells, when exposed to this compound, showed a remarkable subversion of the cytoskeletal architecture characterized by F-actin destabilization, phospho-FAK delocalization, and tubulin depolimerization. These results were definitely concordant in attributing to SI113 a key role in hindering cancer cell malignancy and, due to its negligible in vivo toxicity, can sustain performing a Phase I clinical trial to employ this drug in associative cancer therapy. 相似文献
998.
Elżbieta Supruniuk Agnieszka Mikłosz Adrian Chabowski Bartłomiej Łukaszuk 《Journal of cellular physiology》2019,234(7):11923-11941
Pyrroloquinoline quinone (PQQ) acts as a powerful modulator of PGC-1α activation and therefore regulates multiple pathways involved in cellular energy homeostasis. In the present study, we assessed the effects of L6 myotubes incubation with 0.5, 1, and 3 μM PQQ solution for 2 and 24 hr with respect to the cells' lipid metabolism. We demonstrated that PQQ significantly elevates PGC-1α content in a dose- and time-dependent manner with the highest efficiency for 0.5 and 1 µM. The level of free fatty acids was diminished (24 hr: −66%), while an increase in triacylglycerol (TAG) amount was most pronounced after 0.5 μM (2 hr: +93%, 24 hr: +139%) treatment. Ceramide (CER) content was elevated after 2 hr incubation with 0.5 µM and after prolonged exposure to all PQQ concentrations. The cells treated with PQQ for 2 hr exhibited decreased sphinganine (SFA) and sphinganine-1-phosphate (SFA1P) level, while 24 hr incubation resulted in an elevated sphingosine (SFO) amount. In summary, PGC-1α activation promotes TAG and CER synthesis. 相似文献
999.
Nunzia Zanotta Giuseppina Campisciano Sara Morassut Eugenia Castro-Silva Viviana Luksa Gabriella Zito Stefania Luppi Monica Martinelli Claudia Colli Francesco De Seta Giuseppe Ricci Barbara Suligoi Manola Comar 《Journal of cellular physiology》2019,234(10):17905-17911
Recently, there are controversial opinions on the presence of Mycoplasmas/Ureaplasmas as colonizers or pathogens, and on the use of a targeted therapy. This study aimed to characterize Mycoplasmas/Ureaplasmas infections in reproductive age women, including the acquisition of sexually transmitted (ST) pathogens and poor birth outcomes. A total of 646 healthy Italian women fulfilled the inclusion criteria including 521 infertile women, 65 pregnant women, and 60 fertile women with identified risk factors and symptomatic for vaginitis/cervicitis. Multiplex and quantitative molecular techniques and direct automatic DNA sequencing were performed to assess the genome structure of Mycoplasma/Ureaplasma species and ST infected pathogens. Ureaplasma parvum serovar 3 represented the predominant colonizer of the urogenital tract of this series and the unique species significantly associated with ST pathogens coinfection (p < 0.01). U. parvum load >104 bacteria/ml, suggestive of active infection, has been measured only in asymptomatic high-risk human papillomavirus infected women (24.3%) and in 40% of women with idiopathic infertility. To note, 16% of the follicular fluid from these idiopathic women resulted infected with U. parvum. In conclusion, the present study focused the attention on U. parvum serovar 3 as emerging microorganism in sexually active women that may have the benefit of targeted therapy. 相似文献
1000.
Giacomo Zaccone John Maina Antonino Germanà Giuseppe Montalbano Gioele Capillo Luisa Aragona Michał J. Kuciel Eugenia Rita Lauriano José M. Icardo 《Acta zoologica》2019,100(2):160-166
Available studies that have examined O2 sensing in fish have indicated that oxygen-sensitive neuroepithelial cells (NECs) are O2 sensors in the gills and initiate cardiorespiratory reflexes in aquatic vertebrates. This is the first study describing the occurrence of NECs in accessory respiratory organs in the air-breathing catfish Clarias gariepinus. Immunocytochemical stainings with specific neuronal markers such as nNOS, VAchT, 5-HT and TH have been shown to be very useful for location and distribution of these cells in the gill fans and suprabranchial chamber that take origin from the transformation of the gill tissue. But the response of these putative O2 chemoreceptors, their role in the respiratory reflexes and their innervation await investigation. 相似文献