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排序方式: 共有734条查询结果,搜索用时 17 毫秒
251.
Chuan-Ching Lai Rathinasamy Baskaran Chih-Yu Tsao Li-Heng Tuan Pei-Fen Siow Mahalakshmi Palani Lukas Jyuhn-Hsiarn Lee Chih-Min Liu Hai-Gwo Hwu Li-Jen Lee 《International journal of molecular sciences》2022,23(16)
Symptoms of schizophrenia (SZ) typically emerge during adolescence to young adulthood, which gives a window before full-blown psychosis for early intervention. Strategies for preventing the conversion from the prodromal phase to the psychotic phase are warranted. Heterozygous (Het) Disc1 mutant mice are considered a prodromal model of SZ, suitable for studying psychotic conversion. We evaluated the preventive effect of chronic N-acetylcysteine (NAC) administration, covering the prenatal era to adulthood, on the reaction following the Amph challenge, which mimics the outbreak or conversion of psychosis, in adult Het Disc1 mice. Biochemical and morphological features were examined in the striatum of NAC-treated mice. Chronic NAC treatment normalized the Amph-induced activity in the Het Disc1 mice. Furthermore, the striatal phenotypes of Het Disc1 mice were rescued by NAC including dopamine receptors, the expression of GSK3s, MSN dendritic impairments, and striatal PV density. The current study demonstrated a potent preventive effect of chronic NAC treatment in Disc1 Het mice on the acute Amph test, which mimics the outbreak of psychosis. Our findings not only support the benefit of NAC as a dietary supplement for SZ prodromes, but also advance our knowledge of striatal dopamine receptors, PV neurons, and GSK3 signaling pathways as therapeutic targets for treating or preventing the pathogenesis of mental disorders. 相似文献
252.
Lukas Wesemann Jon Rickett Jingchao Song Jieqiong Lou Elizabeth Hinde Timothy J.Davis Ann Roberts 《光:科学与应用(英文版)》2021,10(6):957-962
The ability to visualise transparent objects such as live cells is central to understanding biological processes. Here we experimentally demonstrate a novel nan... 相似文献
253.
Jamie Dunning Anvay Patil Liliana D'Alba Alexander L. Bond Gerben Debruyn Ali Dhinojwala Matthew Shawkey Lukas Jenni 《Journal of the Royal Society Interface》2023,20(200)
Until recently, and when compared with diurnal birds that use contrasting plumage patches and complex feather structures to convey visual information, communication in nocturnal and crepuscular species was considered to follow acoustic and chemical channels. However, many birds that are active in low-light environments have evolved intensely white plumage patches within otherwise inconspicuous plumages. We used spectrophotometry, electron microscopy, and optical modelling to explain the mechanisms producing bright white tail feather tips of the Eurasian woodcock Scolopax rusticola. Their diffuse reflectance was approximately 30% higher than any previously measured feather. This intense reflectance is the result of incoherent light scattering from a disordered nanostructure composed of keratin and air within the barb rami. In addition, the flattening, thickening and arrangement of those barbs create a Venetian-blind-like macrostructure that enhances the surface area for light reflection. We suggest that the woodcocks have evolved these bright white feather patches for long-range visual communication in dimly lit environments. 相似文献
254.
Lukas M. Bollmann Alexander J. Skerhut Yodita Asfaha Nadine Horstick Helmut Hanenberg Alexandra Hamacher Thomas Kurz Matthias U. Kassack 《International journal of molecular sciences》2022,23(21)
The treatment of leukemias, especially acute myeloid leukemia (AML), is still a challenge as can be seen by poor 5-year survival of AML. Therefore, new therapeutic approaches are needed to increase the treatment success. Epigenetic aberrations play a role in pathogenesis and resistance of leukemia. Histone deacetylase (HDAC) inhibitors (HDACIs) can normalize epigenetic disbalance by affecting gene expression. In order to decrease side effects of so far mainly used pan-HDACIs, this paper introduces the novel highly selective class IIa HDACI YAK540. A synergistic cytotoxic effect was observed between YAK540 and the proteasome inhibitor bortezomib (BTZ) as analyzed by the Chou-Talalay method. The combination of YAK540 and BTZ showed generally increased proapoptotic gene expression, increased p21 expression, and synergistic, caspase 3/7-mediated apoptosis. Notably, the cytotoxicity of YAK540 is much lower than that of pan-HDACIs. Further, combinations of YAK540 and BTZ are clearly less toxic in non-cancer HEK293 compared to HL-60 leukemia cells. Thus, the synergistic combination of class IIa selective HDACIs such as YAK540 and proteasome inhibitors represents a promising approach against leukemias to increase the anticancer effect and to reduce the general toxicity of HDACIs. 相似文献
255.
Robert Greite Li Wang Lukas Gohlke Sebastian Schott Kirill Kreimann Julian Doricic Andreas Leffler Igor Tudorache Jawad Salman Ruslan Natanov Fabio Ius Christine Fegbeutel Axel Haverich Ralf Lichtinghagen Rongjun Chen Song Rong Hermann Haller Vijith Vijayan Magnus Gram Irina Scheffner Faikah Gueler Wilfried Gwinner Stephan Immenschuh 《International journal of molecular sciences》2022,23(21)
Cell-free hemoglobin (CFH), a pro-oxidant and cytotoxic compound that is released in hemolysis, has been associated with nephrotoxicity. Lung transplantation (LuTx) is a clinical condition with a high incidence of acute kidney injury (AKI). In this study, we investigated the plasma levels of CFH and haptoglobin, a CFH-binding serum protein, in prospectively enrolled LuTx patients (n = 20) with and without AKI. LuTx patients with postoperative AKI had higher CFH plasma levels at the end of surgery compared with no-AKI patients, and CFH correlated with serum creatinine at 48 h. Moreover, CFH levels inversely correlated with haptoglobin levels, which were significantly reduced at the end of surgery in LuTx patients with AKI. Because multiple other factors can contribute to AKI development in the complex clinical setting of LuTx, we next investigated the role of exogenous CFH administration in a mouse model of mild bilateral renal ischemia reperfusion injury (IRI). Exogenous administration of CFH after reperfusion caused overt AKI with creatinine increase, tubular injury, and enhanced markers of renal inflammation compared with vehicle-treated animals. In conclusion, CFH is a possible factor contributing to postoperative AKI after LuTx and promotes AKI in an experimental model of mild transient renal ischemia. Targeting CFH might be a therapeutic option to prevent AKI after LuTx. 相似文献
256.
Alberto de la Iglesia Paula Jauregi Meritxell Jodar Ferran Barrachina Lukas Ded Carme Mallofr Leonardo Rodríguez-Carunchio Juan Manuel Corral Josep Lluís Ballesc Katerina Komrskova Judit Castillo Rafael Oliva 《International journal of molecular sciences》2022,23(20)
Male germ cells experience a drastic chromatin remodeling through the nucleo-histone to nucleo-protamine (NH-NP) transition necessary for proper sperm functionality. Post-translational modifications (PTMs) of H4 Lys5, such as acetylation (H4K5ac), play a crucial role in epigenetic control of nucleosome disassembly facilitating protamine incorporation into paternal DNA. It has been shown that butyrylation on the same residue (H4K5bu) participates in temporal regulation of NH-NP transition in mice, delaying the bromodomain testis specific protein (BRDT)-dependent nucleosome disassembly and potentially marking retained nucleosomes. However, no information was available so far on this modification in human sperm. Here, we report a dual behavior of H4K5bu and H4K5ac in human normal spermatogenesis, suggesting a specific role of H4K5bu during spermatid elongation, coexisting with H4K5ac although with different starting points. This pattern is stable under different testicular pathologies, suggesting a highly conserved function of these modifications. Despite a drastic decrease of both PTMs in condensed spermatids, they are retained in ejaculated sperm, with 30% of non-colocalizing nucleosome clusters, which could reflect differential paternal genome retention. Whereas no apparent effect of these PTMs was observed associated with sperm quality, their presence in mature sperm could entail a potential role in the zygote. 相似文献
257.
Nele Wagener Wolfgang Lehmann Lukas Weiser Katharina Jckle Pietro Di Fazio Arndt F. Schilling Kai O. Bker 《International journal of molecular sciences》2022,23(18)
Attention deficit hyperactivity disorder (ADHD) is one of the most common worldwide mental disorders in children, young and adults. If left untreated, the disorder can continue into adulthood. The abuse of ADHD-related drugs to improve mental performance for studying, working and everyday life is also rising. The potentially high number of subjects with controlled or uncontrolled use of such substances increases the impact of possible side effects. It has been shown before that the early ADHD drug methylphenidate influences bone metabolism negatively. This study focused on the influence of three more recent cognitive enhancers, modafinil, atomoxetine and guanfacine, on the differentiation of mesenchymal stem cells to osteoblasts and on their cell functions, including migration. Human mesenchymal stem cells (hMSCs) were incubated with a therapeutic plasma dosage of modafinil, atomoxetine and guanfacine. Gene expression analyses revealed a high beta-2 adrenoreceptor expression in hMSC, suggesting it as a possible pathway to stimulate action. In bone formation assays, all three cognitive enhancers caused a significant decrease in the mineralized matrix and an early slight reduction of cell viability without triggering apoptosis or necrosis. While there was no effect of the three substances on early differentiation, they showed differing effects on the expression of osterix (OSX), receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) in the later stages of osteoblast development, suggesting alternative modes of action. All three substances significantly inhibited hMSC migration. This effect could be rescued by a selective beta-blocker (Imperial Chemical Industries ICI-118,551) in modafinil and atomoxetine, suggesting mediation via beta-2 receptor stimulation. In conclusion, modafinil, atomoxetine and guanfacine negatively influence hMSC differentiation to bone-forming osteoblasts and cell migration through different intracellular pathways. 相似文献
258.
T Kohsaka G Min G Lukas S Trupin ET Campbell OD Sherwood 《Canadian Metallurgical Quarterly》1998,59(4):991-999
Relaxin is secreted during pregnancy, but it has no verified effects in humans. The objective of the present study was to identify the cells containing specific relaxin-binding sites in the uterine cervix, vagina, uterus, mammary glands, mammary nipples, and term placenta in the human. The uterine cervix, vagina, and uterus were obtained from hysterectomy specimens. Mammary glands and nipples were obtained after modified radical mastectomy. Placenta was obtained after normal delivery. Tissue samples were cut into slices (0.5-3 cm3), frozen in liquid nitrogen, and cryosectioned (8 microm). Cells that bind relaxin were identified by sequential application of biotinylated porcine relaxin probe, antibiotin immunoglobulin G conjugated to 1 nm colloidal gold, and silver enhancement for signal amplification. Relaxin bound with specificity to epithelial cells, smooth muscle cells, and blood vessels in the cervix, vagina, uterus, and mammary nipples; to epithelial cells and blood vessels in the mammary glands; and to skin of the mammary nipples. In addition, relaxin bound to individual cell types within the term placenta (amnion epithelium, syncytiotrophoblasts, blood vessels), and to sebaceous glands within the nipples. We conclude that the specific relaxin-binding cells probably contain relaxin receptors. Identification of putative relaxin receptors may provide insight into physiological and/or therapeutic roles of relaxin in the human. 相似文献
259.
Lukas B. Moser Christoph Bauer Vivek Jeyakumar Eugenia-Paulina Niculescu-Morzsa Stefan Nehrer 《International journal of molecular sciences》2021,22(21)
The current study aimed to investigate the cytotoxicity of co-administrating local anesthetics (LA) with glucocorticoids (GC) and hyaluronic acid (HA) in vitro. Human articular cartilage was obtained from five patients undergoing total knee arthroplasty. Chondrocytes were isolated, expanded, and seeded in 24-well plates for experimental testing. LA (lidocaine, bupivacaine, ropivacaine) were administered separately and co-administered with the following substances: GC, HA, and GC/HA. Viability was confirmed by microscopic images, flow cytometry, metabolic activity, and live/dead assay. The addition of HA and GC/HA resulted in enhanced attachment and branched appearance of the chondrocytes compared to LA and LA/GC. Metabolic activity was better in all LA co-administered with HA and GC/HA than with GC and only LA. Flow cytometry revealed the lowest cell viability in lidocaine and the highest cell viability in ropivacaine. This finding was also confirmed by live/dead assay. In conclusion, HA supports the effect of GC and reduces chondrotoxic effects of LA in vitro. Thereby, the co-administration of HA to LA and GC offers an alternative less chondrotoxic approach for treating patients with symptomatic osteoarthritis of the knee. 相似文献
260.
Tomas Floris Petr Kluson Lukas Bartek Helena Pelantova 《Applied Catalysis A: General》2009,366(1):160-165
Chiral catalytic complex (R)—[RuCl(binap)(p-cymene)]Cl was used in asymmetric hydrogenation of methyl acetoacetate to methyl-3-hydroxybutyrate in the mixed methanol-ionic liquid phase. Quaternary ammonium salts ionic liquids, namely n-alkyl-triethylammonium bis(trifluoromethane sulfonyl) imides (NR222Tf2N, R = 6, 7, 8, 10, 12, 14), were prepared and employed in this transformation. Enough evidence was provided that only a small amount of this type of IL in a conventional solvent was necessary to accommodate the catalytic complex and that the reaction could be carried out with very high enantioselectivity. Similarly it was proved that under optimized conditions the catalytic complex immobilized in this manner could be used repeatedly. A part of the work was focused on the role of the alkyl chain length in the NR222Tf2N ionic liquid which was found as very essential. Role of the reaction impurities with origin in the synthesis of the employed ILs was also investigated. 相似文献