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961.
Nakashima H Miyake K Clark CR Bekisz J Finbloom J Husain SR Baron S Puri RK Zoon KC 《Cancer immunology, immunotherapy : CII》2012,61(7):1081-1092
Interferon-activated monocytes are known to exert cytocidal activity against tumor cells in vitro. Here, we have examined whether a combination of IFN-α2a and IFN-γ and human monocytes mediate significant antitumor effects against human ovarian and melanoma tumor xenografts in mouse models. OVCAR-3 tumors were treated i.t. with monocytes alone, IFN-α2a and IFN-γ alone or combination of all three on day 0, 15 or 30 post-tumor implantation. Mice receiving combination therapy beginning day 15 showed significantly reduced tumor growth and prolonged survival including complete regression in 40% mice. Tumor volumes measured on day 80 in mice receiving combination therapy (206 mm(3)) were significantly smaller than those of mice receiving the IFNs alone (1,041 mm(3)), monocytes alone (1,111 mm(3)) or untreated controls (1,728 mm(3)). Similarly, combination therapy with monocytes and IFNs of much larger tumor also inhibited OVCAR-3 tumor growth. Immunohistochemistry studies showed a large number of activated macrophages (CD31(+)/CD68(+)) infiltrating into OVCAR-3 tumors and higher densities of IL-12, IP10 and NOS2, markers of M1 (classical) macrophages in tumors treated with combination therapy compared to the controls. Interestingly, IFNs-activated macrophages induced apoptosis of OVCAR-3 tumor cells as monocytes alone or IFNs alone did not mediate significant apoptosis. Similar antitumor activity was observed in the LOX melanoma mouse model, but not as profound as seen with the OVCAR-3 tumors. Administration of either mixture of monocytes and IFN-α2a or monocytes and IFN-γ did not inhibit Lox melanoma growth; however, a significant inhibition was observed when tumors were treated with a mixture of monocytes, IFN-α2a and IFN-γ. These results indicate that monocytes and both IFN-α2a and IFN-γ may be required to mediate profound antitumor effect against human ovarian and melanoma tumors in mouse models. 相似文献
962.
Liang G Aldous S Merriman G Levell J Pribish J Cairns J Chen X Maignan S Mathieu M Tsay J Sides K Rebello S Whitely B Morize I Pauls HW 《Bioorganic & medicinal chemistry letters》2012,22(2):1049-1054
A solid phase combinatorial library was designed based on X-ray structures and in-silico models to explore an inducible S4+ pocket, which is formed by a simple side-chain rotation of Tyr95. This inducible S4+ pocket is unique to β-tryptase and does not exist for other trypsin-like serine proteases of interest. Therefore, inhibitors utilizing this pocket have inherent advantages for being selective against other proteases in the same family. A member of this library was found to be a potent and selective β-tryptase inhibitor with a suitable pharmacokinetic profile for further clinical evaluation. 相似文献
963.
Burgoyne JR Haeussler DJ Kumar V Ji Y Pimental DR Zee RS Costello CE Lin C McComb ME Cohen RA Bachschmid MM 《FASEB journal》2012,26(2):832-841
Here we demonstrate a new paradigm in redox signaling, whereby oxidants resulting from metabolic stress directly alter protein palmitoylation by oxidizing reactive cysteine thiolates. In mice fed a high-fat, high-sucrose diet and in cultured endothelial cells (ECs) treated with high palmitate and high glucose (HPHG), there was decreased HRas palmitoylation on Cys181/184 (61±24% decrease for cardiac tissue and 38±7.0% in ECs). This was due to oxidation of Cys181/184, detected using matrix-assisted laser desorption/ionization time of flight (MALDI TOF)-TOF. Decrease in HRas palmitoylation affected its compartmentalization and Ras binding domain binding activity, with a shift from plasma membrane tethering to Golgi localization. Loss of plasma membrane-bound HRas decreased growth factor-stimulated ERK phosphorylation (84±8.6% decrease) and increased apoptotic signaling (24±6.5-fold increase) after HPHG treatment that was prevented by overexpressing wild-type but not C181/184S HRas. The essential role of HRas in metabolic stress was made evident by the similar effects of expressing an inactive dominant negative N17-HRas or a MEK inhibitor. Furthermore, the relevance of thiol oxidation was demonstrated by overexpressing manganese superoxide dismutase, which improved HRas palmitoylation and ERK phosphorylation, while lessening apoptosis in HPHG treated ECs. 相似文献
964.
Jenna M. McCullough Leo Joseph Robert G. Moyle Michael J. Andersen 《Zoologica scripta》2019,48(4):411-418
Molecular systematics is bringing taxonomy into the 21st Century by updating our nomenclature to reflect phylogenetic relationships of taxa. This transformation is evidenced by massive changes in avian taxonomy, ranging from ordinal to subspecies changes. In this study, we employ target capture of ultraconserved elements to resolve genus‐level systematics of a problematic group of honeyeaters (Aves: Meliphagidae). With near complete species‐level taxon sampling of the Australo‐Papuan species within the traditionally recognized Meliphaga and Oreornis, we investigate generic limits using a genomic dataset. Likelihood and species tree methods confirm two clades within this group and found the New Guinea endemic Oreornis chrysogenys embedded within one of these clades. Our study supports earlier recommendations that Meliphaga Lewin, 1808 should be restricted to three species, M. aruensis, M. lewinii and M. notata. We make a case for recognizing three genera in the remaining species, Oreornis van Oort, 1910, Microptilotis Mathews, 1912 and Territornis Mathews, 1924. 相似文献
965.
966.
Eugene Tulchinsky Oleg Demidov Marina Kriajevska Nickolai A. Barlev Evgeny Imyanitov 《生物化学与生物物理学报:癌评论》2019,1871(1):29-39
Epithelial mesenchymal transition (EMT) is a reversible developmental genetic programme of transdifferentiation of polarised epithelial cells to mesenchymal cells. In cancer, EMT is an important factor of tumour cell plasticity and has received increasing attention for its role in the resistance to conventional and targeted therapies. In this paper we provide an overview of EMT in human malignancies, and discuss contribution of EMT to the development of the resistance to Epidermal Growth Factor Receptor (EGFR)-targeted therapies in non-small cell lung cancer (NSCLC). Patients with the tumours bearing specific mutations in EGFR have a good clinical response to selective EGFR inhibitors, but the resistance inevitably develops. Several mechanisms responsible for the resistance include secondary mutations in the EGFR gene, genetic or non-mutational activation of alternative survival pathways, transdifferentiation of NSCLC to the small cell lung cancer histotype, or formation of resistant tumours with mesenchymal characteristics. Mechanistically, application of an EGFR inhibitor does not kill all cancer cells; some cells survive the exposure to a drug, and undergo genetic evolution towards resistance. Here, we present a theory that these quiescent or slow-proliferating drug-tolerant cell populations, or so-called “persisters”, are generated via EMT pathways. We review the EMT-activated mechanisms of cell survival in NSCLC, which include activation of ABC transporters and EMT-associated receptor tyrosine kinase AXL, immune evasion, and epigenetic reprogramming. We propose that therapeutic inhibition of these pathways would eliminate pools of persister cells and prevent or delay cancer recurrence when applied in combination with the agents targeting EGFR. 相似文献
967.
968.
969.
Carmel Bilu Haim Einat Katy Tal-Krivisky Joseph Mizrahi Vicktoria Vishnevskia-Dai Galila Agam 《Chronobiology international》2019,36(7):919-926
Despite the common use of bright light exposure for treatment of seasonal affective disorder (SAD), the underlying biology of the therapeutic effect is not clear. Moreover, there is a debate regarding the most efficacious wavelength of light for treatment. Whereas according to the traditional approach full-spectrum light is used, recent studies suggest that the critical wavelengths are within the range of blue light (460 and 484 nm). Our previous work shows that when diurnal rodents are maintained under short photoperiod they develop depression- and anxiety-like behavioral phenotype that is ameliorated by treatment with wide-spectrum bright light exposure (2500 lux at the cage, 5000 K). Our current study compares the effect of bright wide-spectrum (3,000 lux, wavelength 420- 780 nm, 5487 K), blue (1,300 lux, wavelength 420-530 nm) and red light (1,300 lux, wavelength range 600-780 nm) exposure in the fat sand rat (Psammomys Obesus) model of SAD. We report results of experiments with six groups of sand rats that were kept under various photoperiods and light treatments, and subjected to behavioral tests related to emotions: forced swim test, elevated plus maze and social interactions. Exposure to either intense wide-spectrum white light or to blue light equally ameliorated depression-like behavior whereas red light had no effect. Bright wide-spectrum white light treatment had no effect on animals maintained under neutral photoperiod, meaning that light exposure was only effective in the pathological-like state. The resemblance between the effects of bright white light and blue light suggests that intrinsically photosensitive retinal ganglion cells (ipRGCs) are involved in the underlying biology of SAD and light therapy. 相似文献
970.
Eugene A. Marino 《American journal of physical anthropology》1995,97(2):127-133
The articular surfaces and vertebral foramen area of the first cervical vertebra are sexually dimorphic and can be used to sex complete or fragmentary specimens. Eight measurements were taken from the articular regions (superior and inferior) of 100 first cervical vertebrae from Terry collection specimens housed at the Smithsonian Institution. Seven regression and seven discriminant function equations were created that predict sex with 77–85% and 75–85% accuracy, respectively. In separate control tests, measurements from 100 first cervical vertebrae from Hamann-Todd collection individuals (Cleveland Museum of Natural History) and from 34 archaeological specimens were used with the Terry equations. The control samples were sexed with 60—85% accuracy. © 1995 Wiley-Liss, Inc. 相似文献