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21.
Nikolaos Salakius 《Geobios》1982,15(6):873-889
A new, strongly spiroconvex Globotruncana species,Globotruncana pseudoconica nov. sp., is described from the Maastrichtian of Tunisia. It is distinguished from Globotruncana conicaWhite in morphology and phylogeny. Some Maastrichtian, strongly spiroconvex specimens referred to as Globotruncana conicaWhite, are shown to be identical to Globotruncana pseudoconica nov. sp. The new species reveals close affinity with Globotruncana falsostuartiSigal from which it has evolved during the middle Lower Maastrichtian. 相似文献
22.
Nikolaos Pagonas Wolfgang Vautz Luzia Seifert Rafael Slodzinski Joachim Jankowski Walter Zidek Timm H. Westhoff 《PloS one》2012,7(9)
Background
Although “uremic fetor” has long been felt to be diagnostic of renal failure, the compounds exhaled in uremia remain largely unknown so far. The present work investigates whether breath analysis by ion mobility spectrometry can be used for the identification of volatile organic compounds retained in uremia.Methods
Breath analysis was performed in 28 adults with an eGFR ≥60 ml/min per 1.73 m2, 26 adults with chronic renal failure corresponding to an eGFR of 10–59 ml/min per 1.73 m2, and 28 adults with end-stage renal disease (ESRD) before and after a hemodialysis session. Breath analysis was performed by ion mobility spectrometryafter gas-chromatographic preseparation. Identification of the compounds of interest was performed by thermal desorption gas chromatography/mass spectrometry.Results
Breath analyses revealed significant differences in the spectra of patients with and without renal failure. Thirteen compounds were chosen for further evaluation. Some compounds including hydroxyacetone, 3-hydroxy-2-butanone and ammonia accumulated with decreasing renal function and were eliminated by dialysis. The concentrations of these compounds allowed a significant differentiation between healthy, chronic renal failure with an eGFR of 10–59 ml/min, and ESRD (p<0.05 each). Other compounds including 4-heptanal, 4-heptanone, and 2-heptanone preferentially or exclusively occurred in patients undergoing hemodialysis.Conclusion
Impairment of renal function induces a characteristic fingerprint of volatile compounds in the breath. The technique of ion mobility spectrometry can be used for the identification of lipophilic uremic retention molecules. 相似文献23.
24.
Theoharides TC Alysandratos KD Angelidou A Delivanis DA Sismanopoulos N Zhang B Asadi S Vasiadi M Weng Z Miniati A Kalogeromitros D 《Biochimica et biophysica acta》2012,1822(1):21-33
Mast cells are well known for their role in allergic and anaphylactic reactions, as well as their involvement in acquired and innate immunity. Increasing evidence now implicates mast cells in inflammatory diseases where they are activated by non-allergic triggers, such as neuropeptides and cytokines, often exerting synergistic effects as in the case of IL-33 and neurotensin. Mast cells can also release pro-inflammatory mediators selectively without degranulation. In particular, IL-1 induces selective release of IL-6, while corticotropin-releasing hormone secreted under stress induces the release of vascular endothelial growth factor. Many inflammatory diseases involve mast cells in cross-talk with T cells, such as atopic dermatitis, psoriasis and multiple sclerosis, which all worsen by stress. How mast cell differential responses are regulated is still unresolved. Preliminary evidence suggests that mitochondrial function and dynamics control mast cell degranulation, but not selective release. Recent findings also indicate that mast cells have immunomodulatory properties. Understanding selective release of mediators could explain how mast cells participate in numerous diverse biologic processes, and how they exert both immunostimulatory and immunosuppressive actions. Unraveling selective mast cell secretion could also help develop unique mast cell inhibitors with novel therapeutic applications. This article is part of a Special Issue entitled: Mast cells in inflammation. 相似文献
25.
Athina Lani Nikolaos Kourkoumelis Gerasimos Baliouskas Margaret Tzaphlidou 《Journal of biological physics》2014,40(4):401-412
Fourier transform infrared spectroscopy is utilized to examine the effects of increased calcium, vitamin D, and combined calcium-vitamin D supplementation on osteoporotic rabbit bones with induced inflammation. The study includes different bone sites (femur, tibia, humerus, vertebral rib) in an effort to explore possible differences among the sites. We evaluate the following parameters: mineral-to-matrix ratio, carbonate content, and non-apatitic species (labile acid phosphate and labile carbonate) contribution to bone mineral. Results show that a relatively high dose of calcium or calcium with vitamin D supplementation increases the bone mineralization index significantly. On the other hand, vitamin D alone is not as effective in promoting mineralization even with high intake. Mature B-type apatite was detected for the group with calcium supplementation similar to that of aged bone. High vitamin D intake led to increased labile species concentration revealing bone formation. This is directly associated with the suppression of pro-inflammatory cytokines linked to induced inflammation. The latter is known to adversely alter bone metabolism, contributing to the aetiopathogenesis of osteoporosis. Thus, a high intake of vitamin D under inflammation-induced osteoporosis does not promote mineralization but suppresses bone resorption and restores metabolic balance. 相似文献
26.
Rottoli P Magi B Perari MG Liberatori S Nikiforakis N Bargagli E Cianti R Bini L Pallini V 《Proteomics》2005,5(5):1423-1430
The aim of this study was to analyze the type of immune response (Th1, Th2) and protein composition of bronchoalveolar lavage (BAL) of patients with sarcoidosis, pulmonary fibrosis associated with systemic sclerosis (SSc) and idiopathic pulmonary fibrosis (IPF). Flow cytometry analysis of intracellular cytokines revealed different patterns: in IPF and SSc Th2 profiles were predominant, whereas in sarcoidosis Th1 prevailed. The proteomic analysis of BAL fluid (BALF) showed that there were quantitative differences between the three diseases. These were more evident between sarcoidosis and IPF, confirming our previous observations, whereas SSc had an intermediate profile between the two, however with some peculiarities. Comparison of BALF protein maps, constructed with the same quantity of total proteins, enabled us to identify the main profiles of the three diseases: an increase in plasma protein prevalent in sarcoidosis and also present in SSc, though for fewer proteins with respect to IPF and a greater abundance of low molecular weight proteins, mainly locally produced, in IPF. These findings are in line with the different pathogenesis of these diseases: IPF is considered a prevalently fibrotic disorder limited to the lung, with intense local production of functionally different proteins, whereas sarcoidosis and SSc are systemic immunoinflammatory diseases. 相似文献
27.
Estimation of hand forces and propelling efficiency during front crawl swimming with hand paddles 总被引:1,自引:0,他引:1
Gourgoulis V Aggeloussis N Vezos N Kasimatis P Antoniou P Mavromatis G 《Journal of biomechanics》2008,41(1):208-215
The aim of the study was to investigate possible modifications caused by hand paddles in the relative contribution of the lift and drag forces of the hand and in the propelling efficiency, during front crawl swimming. Eight female swimmers swam 25 m with maximal intensity without paddles, with small (116 cm(2)) and with large paddles (268 cm(2)). Four cameras operating at 60 Hz were used to record the images and the Ariel Performance Analysis System was used for the digitisation. The results showed that, although during swimming with hand paddles the hand's velocity decreased, the greater propulsive area of the hand paddle caused an increase in the drag, lift, resultant and effective forces of the hand. However, the relative contribution of lift and drag forces on swimming propulsion was not modified, nor was the direction of the resultant force. Hand paddles also increased the propelling efficiency, the stroke length and the swimming velocity, mainly because of the larger propulsive areas of the hand in comparison with free swimming. However, the significant decrease of the stroke rate, might argue the effectiveness of hand paddle training, particularly when large paddles are used in front crawl swimming. 相似文献
28.
Mobilization of photosystem II induced by intense red light in the Cyanobacterium Synechococcus sp PCC7942 下载免费PDF全文
We use confocal fluorescence microscopy and fluorescence recovery after photobleaching to show that a specific light signal controls the diffusion of a protein complex in thylakoid membranes of the cyanobacterium Synechococcus sp PCC7942 in vivo. In low light, photosystem II appears completely immobile in the membrane. However, exposure to intense red light triggers rapid diffusion of up to approximately 50% of photosystem II reaction centers. Particularly intense or prolonged red light exposure also leads to the redistribution of photosystem II to specific zones within the thylakoid membranes. The mobilization does not result from photodamage but is triggered by a specific red light signal. We show that mobilization of photosystem II is required for the rapid initiation of recovery from photoinhibition. Thus, intense red light triggers a switch from a static to a dynamic configuration of thylakoid membrane protein complexes, and this facilitates the rapid turnover and repair of the complexes. The localized concentrations of photosystem II seen after red light treatment may correspond to specific zones where the repair cycle is active. 相似文献
29.
Variation in plant diversity in mediterranean‐climate ecosystems: the role of climatic and topographical stability 下载免费PDF全文
30.
Croasdale R Wartha K Schanzer JM Kuenkele KP Ries C Mayer K Gassner C Wagner M Dimoudis N Herter S Jaeger C Ferrara C Hoffmann E Kling L Lau W Staack RF Heinrich J Scheuer W Stracke J Gerdes C Brinkmann U Umana P Klein C 《Archives of biochemistry and biophysics》2012,526(2):206-218
In this study we present novel bispecific antibodies that simultaneously target the insulin-like growth factor receptor type I (IGF-1R) and epidermal growth factor receptor (EGFR). For this purpose disulfide stabilized scFv domains of the EGFR/ADCC antibody GA201 were fused via serine-glycine connectors to the C-terminus of the heavy (XGFR2) or light chain (XGFR4), or the N-termini of the light (XGFR5) or heavy chain (XGFR3) of the IGF-1R antibody R1507 as parental IgG1 antibody. The resulting bispecific IGF-1R-EGFR antibodies XGFR2, XGFR3 and XGFR4 were successfully generated with yields and stability comparable to conventional IgG1 antibodies. They effectively inhibited IGF-1R and EGFR phosphorylation and 3D proliferation of H322M and H460M2 tumor cells, induced strong down-modulation of IGF-1R as well as enhanced EGFR down-modulation compared to the parental EGFR antibody GA201 and were ADCC competent. The bispecific XGFR derivatives showed a strong format dependent influence of N- or C-terminal heavy and light chain scFv attachment on ADCC activity and an increase in receptor downregulation over the parental combination in vitro. XGFR2 and XGFR4 were selected for in vivo evaluation and showed potent anti-tumoral efficacy comparable to the combination of monospecific IGF-1R and EGFR antibodies in subcutaneous BxPC3 and H322M xenograft models. In summary, we have managed to overcome issues of stability and productivity of bispecific antibodies, discovered important antibody fusion protein design related differences on ADCC activity and receptor downmodulation and show that IGF-1R-EGFR antibodies represent an attractive therapeutic strategy to simultaneously target two key components de-regulated in multiple cancer types, with the ultimate goal to avoid the formation of resistance to therapy. 相似文献