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41.
Bjarnarson SP Jakobsen H Del Giudice G Trannoy E Siegrist CA Jonsdottir I 《European journal of immunology》2005,35(4):1037-1045
The aim of vaccination is to rapidly elicit protective immunity and generate memory for sustained protection. We studied the induction and persistence of polysaccharide (PS)-specific memory in neonatal and infant mice primed with pneumococcal conjugate (Pnc1-TT) by assessing the response to native pneumococcal PS (PPS-1), the kinetics of the PPS-1-specific IgG response to a second Pnc1-TT dose and affinity maturation. A subcutaneous (s.c.) Pnc1-TT booster induced a rapid increase in PPS-1-specific IgG, indicating efficient priming for memory by a single dose of Pnc1-TT already at 1 week of age. High levels were maintained for >12 weeks. However, a PPS-1 booster induced no response in neonatal or infant mice. The adjuvant LT-K63 significantly enhanced the IgG response and affinity to Pnc1-TT by both the s.c. and the intranasal (i.n.) route in all age groups. In neonatal and infant mice, PPS-1 and LT-K63 induced a booster response only when given i.n. following either s.c. or i.n. priming with Pnc1-TT and LT-K63. In contrast, PPS-1 with or without LT-K63 administered s.c. compromised the ongoing PPS-1-specific response elicited in neonatal mice by either s.c. or i.n. priming with Pnc1-TT and LT-K63. These results demonstrate the advantage of the mucosal route for elicitation of PS-specific memory responses in early life. 相似文献
42.
Lucia MB Rutella S Leone G Larocca LM Vella S Cauda R 《Journal of acquired immune deficiency syndromes (1999)》2002,30(4):369-378
P-glycoprotein (P-gp) transports a wide range of structurally unrelated drugs, such as HIV protease inhibitors (PIs) and cytotoxic compounds such as anthracyclines. Because modification of P-gp phenotype and function is an important underlying mechanism of drug interactions, the current study was conducted in order to evaluate whether highly active antiretroviral therapy (HAART), HIV plasma viral load (VL), or cancer chemotherapy may induce in vivo changes of P-gp phenotype in peripheral blood mononuclear cells (PBMCs) from HIV-infected treatment-naive and -experienced subjects at different stages of HIV infection and/or disease, including patients with HIV-associated Kaposi sarcoma (KS). Our results show that neither HAART nor HIV VL, nor the stage of HIV infection and/or disease, significantly alter P-gp expression on PBMCs. In particular, surface P-gp expression is expressed at low levels by T-cell subsets, B cells, and NK cells, whereas almost all monocytes are double positive and these results are not modified by HIV PI-containing regimens. By contrast, a significant phenotype modification is detected in PBMCs from AIDS/KS patients after challenge with the liposomal formulation of the anthracycline doxorubicin (L-DOX) with the higher expression reached 24 hours after the end of the drug infusion. In addition, accumulation of L-DOX is unaffected by P-gp-mediated drug efflux as documented by in vitro experiments, in sharp contrast to the kinetic of free DOX, based on HIV PI blockade experiments. Finally, P-gp expression was found in KS spindle cells from HIV-infected treatment-naive AIDS/KS patients. We conclude that P-gp phenotype in PBMCs and specific subsets is not altered by HAART and/or HIV, whereas a significant increase is induced by specific anticancer drugs such as L-DOX. Moreover, HIV PIs possess an inhibitory effect on P-gp function that may improve DOX sensitivity in KS spindle cells. 相似文献
43.
Maristella?D'Uva Ida?Strina Antonio?Mollo Antonio?Ranieri Giuseppe?De Placido Pierpaolo?Di MiccoEmail author 《Journal of translational medicine》2005,3(1):43
Background
Antiphospholipid syndrome (APS) has been often associated to RPL since 1980 and some reports in the Literature rarely described antibodies to factor XII in patients with APS. 相似文献44.
Nappi C Di Spiezio Sardo A Guerra G Di Carlo C Bifulco G Acunzo G Sammartino A Galli V 《Menopause (New York, N.Y.)》2004,11(4):447-455
OBJECTIVE: To compare nasal symptomatology and function and local concentrations of estradiol (E2), estradiol receptor (ERalpha), vasoactive intestinal peptide (VIP), substance P (SP) and neuropeptide Y (NPY) in nasal biopsies of 20 postmenopausal women complaining of paradoxical nasal stuffiness before and after treatment with intranasal or transdermal E2. DESIGN: Twenty healthy postmenopausal women willing to start hormone therapy (HT) were allocated to one of two groups, using a computer-generated randomization list.Ten postmenopausal women were treated with transdermal 17beta-estradiol 50 microg daily plus nomegestrole acetate 5 mg/day for 12 days per 28-day cycle for 6 months (Group A). Ten postmenopausal women were treated with intranasal 17beta-estradiol 300 microg/day (one spray delivery of 150 microg per nostril) plus nomegestrole acetate 5 mg/day for 12 days per 28-day cycle for 6 months (Group B). Fourteen fertile women undergoing nasal mucosa biopsy during plastic surgery were used as controls for the immunohistochemical evaluation (Group C).All women in groups A and B underwent evaluation of nasal stuffiness score, mucociliary transport time, rhinoscopy, and active anterior rhinomanometry at the beginning of the study and after, VIP, SP, and 6 months of HT. Nasal biopsies and evaluation of local concentrations of E2, ERalpha NPY were performed in groups A and B before and after 6 months of HT and in group C. RESULTS: Both intranasal and transdermal HT improve nasal symptomatology and nasal mucosa appearance and reduce mean mucociliary transport time. The effectiveness of intranasally administered therapy at improving nasal function is significantly better than transdermal therapy. In comparison with premenopausal controls, untreated postmenopausal women of group A and B showed significantly decreased immunopositivity for E2, ERalpha, and SP. HT induced a significant increase in E2, ERalpha, VIP, and SP and a decrease in NPY immunopositivity. Intranasal therapy was associated with a significantly higher immunopositivity for VIP and SP. CONCLUSIONS: HT improves nasal function and symptomatology in postmenopausal women with paradoxical nasal stuffiness, modulating nasal mucosa function through an action on cholinergic, adrenergic, and sensory peptides. Intranasally administered HT is more effective at improving nasal function than transdermal HT. 相似文献
45.
Effects of HDL3 on the expression of matrix-degrading proteases in human endothelial cells 总被引:1,自引:0,他引:1
Norata GD Pellegatta F Hamsten A Catapano AL Eriksson P 《International journal of molecular medicine》2003,12(1):73-78
Modified lipoproteins have been suggested to modulate the expression of matrix-degrading proteases in the vascular wall. Since oxidized high density lipoprotein (HDL) has been found in atheromatous plaques and receptors for modified HDL are present on endothelial cells, we investigated the role of native and oxidized HDL3 on the expression of 35 proteases and their inhibitors in human endothelial cells using microarray analysis. Matrix metalloproteinase (MMP)-1, -2, -10, -13 and -14, tissue inhibitor of MMP (TIMP)-1, -2 and -3, cathepsin B and D, and cystatin C were expressed under basal conditions, of which MMP-10 and cystatin C expression have not been described before in endothelial cells. Native HDL3 increased MMP-1 and MMP-14 expression and decreased MMP-13 expression, whereas oxidized HDL3 increased PAI-1 and MMP-1 expression. The expression pattern was confirmed by quantitative real-time PCR. In summary, a large repertoire of matrix-degrading proteases is expressed in endothelial cells, an expression that can be modulated by native and oxidized HDL3. 相似文献
46.
Radi O Parma P Imbeaud S Nasca MR Uccellatore F Maraschio P Tiepolo L Micali G Camerino G 《American journal of medical genetics. Part A》2005,(3):241-246
We describe a large inbred Sicilian family that includes four 46, XX (SRY-) brothers. Palmoplantar hyperkeratosis (PPK) and an associated predisposition to squamous cell carcinoma (SCC) of the skin, segregates as a recessive trait within the family. Interestingly, all the PPK-affected members of the family are phenotypic males (46,XY or 46,XX) while seven XX sibs are healthy phenotypic females with no signs of PPK. We propose that homozygosity for a single mutational event, possibly including contiguous genes, may cause PPK/SCC in both XY or XX individuals and sex reversal in XX individuals. The family is informative for linkage analysis for the PPK trait and allows linkage exclusion for the sex reversal trait. Here we show that 15 loci involved in PPK etiology, skin differentiation, function or malignancy, and nine loci involved in sex determination/differentiation are not implicated in the phenotype of this family. 相似文献
47.
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
48.
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
49.
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
50.