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81.
Niggli HJ Tudisco S Privitera G Applegate LA Scordino A Musumeci F 《Journal of biomedical optics》2005,10(2):024006
Photobiological research in the last 30 yr has shown the existence of ultraweak photon emission in biological tissue, which can be detected with sophisticated photomultiplier systems. Although the emission of this ultraweak radiation, often termed biophotons, is extremely low in mammalian cells, it can be efficiently increased by ultraviolet light. Most recently it was shown that UV-A (330 to 380 nm) releases such very weak cell radiation in differentiated human skin fibroblasts. Based on these findings, a new and powerful tool in the form of UV-A-laser-induced biophotonic emission of cultured cells was developed with the intention to detect biophysical changes between carcinogenic and normal cells. With suspension densities ranging from 1 to 8 x 10(6) cells/mL, it was evident that an increase of the UV-A-laser-light induced photon emission intensity could be observed in normal as well as melanoma cells. Using this new detection procedure of ultraweak light emission, photons in cell suspensions as low as 100 microL could be determined, which is a factor of 100 lower compared to previous procedures. Moreover, the detection procedure has been further refined by turning off the photomultiplier system electronically during irradiation leading to the first measurements of induced light emission in the cells after less than 10 micros instead of 150 ms, as reported in previous procedures. This improvement leads to measurements of light bursts up 10(7) photons/s instead of several hundred as found with classical designs. Overall, we find decreasing induction ratings between normal and melanoma cells as well as cancer-prone and melanoma cells. Therefore, it turns out that this highly sensitive and noninvasive device enables us to detect high levels of ultraweak photon emission following UV-A-laser-induced light stimulation within the cells, which enables future development of new biophysical strategies in cell research. 相似文献
82.
Vegetarians may have subtle nutritional deficiencies which have been related to the occurrence of an unrecognized malabsorption syndrome. The excess phytate content in cereals, nuts, legumes and oilseeds which represent the mainstay of their food intake, seems to play a central role in the pathogenesis of this malabsorption syndrome as an inverse relationship has been shown to link the phytate content of the diet with the intestinal absorption of trace minerals and proteins. We postulate that manipulating the endogenous digestive microflora of subjects on a vegetarian diet through administering probiotic lactic bacteria would represent an innovative tool to counteract the occurrence of the malabsorption syndrome dependent on the high phytate content of their diet. Even though there are no data about the composition of endogenous digestive microflora in subjects on a vegetarian diet, we expect that probiotic lactobacilli can interact with or affect distinct yet interrelated components within the intestinal milieu, such as epithelial cells, enteric flora, and/or mucosal immune cells. This would ultimately translate into the correction of the unregulated mechanisms implicated in the altered intestinal absorption of trace metals and proteins commonly seen in vegetarians. Clinical experience with probiotic therapy of patients with inflammatory bowel disease fully agrees with this view. One additional point of interest is that probiotic lactobacilli, and other species of the endogenous digestive microflora as well, are an important source of the enzyme phytase which catalyses the release of phosphate from phytate and hydrolyses the complexes formed by phytate and metal ions or other cations, rendering them more soluble ultimately improving and facilitating their intestinal absorption. The regular intake of probiotic preparation, may represent a cheap and safe tool in order to convert a diet with a low potential for bioavailability of trace minerals and proteins, such as the vegetarian diet, into a diet with a high bioavailability potential. The benefit of such an approach would not be restricted to vegetarians. 相似文献
83.
Carolina Scagnolari Francesca Bellomi Ombretta Turriziani Francesca Bagnato Valentina Tomassini Vito Lavolpe Marilena Ruggieri Fabrizio Bruschi Giuseppe Meucci Giordano Dicuonzo Guido Antonelli 《Journal of interferon & cytokine research》2002,22(2):207-213
The frequencies of anti-interferon-beta (IFN-beta) antibody development reported to date in patients treated with different IFN-beta preparations are not readily comparable mainly because of differences in underlying diseases and assay methods. Thus, the frequency of neutralizing antibody (NAb) and binding antibody (BAb) development was analyzed in a sample of sera derived from a homogeneous group of relapsing-remitting multiple sclerosis (RRMS) patients treated with different IFN-beta preparations. The frequency of developing NAb and BAb to IFN-beta varied according to the IFN-beta given. Specifically, the NAb seroconversion frequency was significantly higher in patients treated with Betaferon, Schering AG, Berlin, Germany (31.3%) than in patients treated with both preparations of recombinant IFN-beta 1a (Rebif, Serono, Geneva, Switzerland [7.4%] or Avonex, Biogen, Cambridge, MA [6.3%]). Analysis of BAb seroconversion frequency in the same patients revealed that different IFN-beta preparations may also have different capability to induce BAb development and that BAb are produced during IFN-beta therapy at a significantly higher rate than NAb. Our main conclusion is that different human IFN-beta preparations may possess different immunogenicities, leading to varying frequency of development of antibody to IFN-beta in RRMS. 相似文献
84.
85.
Ruggero Ridolfi Massimiliano Petrini Laura Fiammenghi Monica Stefanelli Laura Ridolfi Michela Ballardini Giuseppe Migliori Angela Riccobon 《Journal of translational medicine》2006,4(1):36-11
Background
We present our experience of therapeutic vaccination using dendritic cells (DC) pulsed with autologous tumor antigens in patients with advanced melanoma. 相似文献86.
87.
Foxl2 disruption causes mouse ovarian failure by pervasive blockage of follicle development 总被引:6,自引:0,他引:6
Uda M Ottolenghi C Crisponi L Garcia JE Deiana M Kimber W Forabosco A Cao A Schlessinger D Pilia G 《Human molecular genetics》2004,13(11):1171-1181
FOXL2 mutations cause gonadal dysgenesis or premature ovarian failure (POF) in women, as well as eyelid/forehead dysmorphology in both sexes (the 'blepharophimosis-ptosis-epicanthus inversus syndrome', BPES). Here we report that mice lacking Foxl2 recapitulate relevant features of human BPES: males and females are small and show distinctive craniofacial morphology with upper eyelids absent. Furthermore, in mice as in humans, sterility is confined to females. Features of Foxl2 null animals point toward a new mechanism of POF, with all major somatic cell lineages failing to develop around growing oocytes from the time of primordial follicle formation. Foxl2 disruption thus provides a model for histogenesis and reproductive competence of the ovary. 相似文献
88.
Patrizia Canale Francesco Squadrito Domenica Altavilla Mariapatrizia Ioculano Basilia Zingarelli Giuseppe M. Campo Giuseppe Urna Aurora Sardella Giovanni Squadrito Achille P. Capuli 《Inflammation research》1994,42(3-4):128-134
The aim of this study was to evaluate: (1) the accumulation of leukocytes in the ileum and the lung during splanchnic artery occlusion (SAO) shock; (2) the role of platelet-activating factor (PAF) and tumor necrosis factor (TNF-) in this phenomenon. Untreated anesthetized rats subjected to total occlusion of the celiac, superior and inferior mesenteric arteries for 45 min, followed by reperfusion, uniformly died within 90 min after reperfusion. The mean survival time was 93±7 min. The neutrophilic infiltrate was quantitated in the ileum and in the lung using a myeloperoxidase (MPO) assay. MPO activity in the ileum and in the lung averaged 0.05±0.03 and 0.4±0.02 U×10–3/g protein in animals killed before occlusion. MPO activity did not change in rats killed immediately before reperfusion and was significantly elevated (0.11±0.02 and 1.7±0.6 U×10–3/g protein in the ileum and the lung, respectively) in those killed 80 min after the beginning of the reperfusion. The histological examination confirmed the accumulation of leukocytes in the mucosa of the ileum and the lung over the 80 min. SAO shocked rats exhibited leukopenia and increased serum levels of TNF-. In order to evaluate the role of PAF and TNF- in SAO shock, a powerful PAF receptor antagonist, TCV-309 (5 g/kg i.v.), was injected 5 min after reperfusion. TCV-309 increased survival time, lowered serum TNF-, reduced MPO activity in both the ileum and the lung and ameliorated leukopenia induced by SAO shock. In addition, the drug significantly reduced ileal necrosis and pulmonary morphological alterations induced by shock. These results suggest an important role for PAF in the adhesion of leukocytes in SAO shock. 相似文献
89.
Giuseppe Giuffrè Rosario Alberto Caruso Gaetano Barresi G. Tuccari 《Virchows Archiv : an international journal of pathology》1998,432(3):261-266
To assess the prognostic significance of silver-stained nucleolar organizer region (AgNOR) proteins, a standardized AgNOR
analysis was performed on 78 patients affected by early (EGC, n=24) or advanced (AGC, n=54) gastric carcinomas. The histopathological diagnosis, grading and staging were done according to WHO and UICC recommendations;
the mean follow-up time was 56.9 months. Visualization and quantification of AgNORs were made in formalin-fixed, paraffin-embedded
sections as specified in the guidelines of the Committee on AgNOR Quantification (1995). Statistical analysis was performed
on the mean AgNOR area values (NORA). Highly significant differences (P<0.001) were found in NORA values between EGC and AGC, between low- and high-grade gastric carcinomas and between patients
dead from gastric cancer and living patients. In addition, significant P values were found on comparison of NORA values relating to pT status, pN status and stage. Comparison of Kaplan-Meier survival
curves revealed that patients affected by gastric carcinomas with higher NORA values (>5.213 μm2) had a worse prognosis. Finally, using Cox multiple regression analysis, the AgNOR quantity emerged as a useful independent
prognostic variable to predict the final outcome of patients affected by EGC or AGC.
Received: 26 September 1997 / Accepted: 26 January 1998 相似文献
90.