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1.
Alternative pathway complement activation induces proinflammatory activity in human proximal tubular epithelial cells 总被引:7,自引:1,他引:6
David S; Biancone L; Caserta C; Bussolati B; Cambi V; Camussi G 《Nephrology, dialysis, transplantation》1997,12(1):51-56
Background. Proximal tubular epithelial cells express
a surface C3-convertase activity which induces C fixation and insertion of
the C5b-9 membrane attack complex (MAC) into the cell plasma membrane. The
physiopathological consequences of this phenomenon are unknown.
Methods. The effect of C fixation on the production of
inflammatory mediators by human proximal tubular epithelial cells in
culture was explored. Results. Proximal tubular
epithelial cells incubated with a sublytic amount of normal human serum as
a source of C, but not with heat-inactivated human serum, showed a
time-dependent calcium influx and a concomitant release of
14C-arachidonic acid
(14C-AA). Eicosanoid synthesis following the
arachidonic acid mobilization was studied as prostaglandin E2 release.
Mg2+/EGTA, which did not prevent C activation by the
C3-convertase, and p-bromodiphenacyl bromide, a phospholipase A2-inhibitor,
inhibited mobilization of 14C-AA. These results
suggest the activation of an extracellular
Ca2+-dependent, phospholipase A2. Complement
fixation was associated with the synthesis of proinflammaotry cytokines
such as IL-6 and TNF-&agr;. Experiments with C6-deficient sera
indicated that the release of 14C-AA and the
production of cytokines were dependent on the insertion of the terminal
components of complement in the plasma membrane. Indeed, the reconstitution
of normal haemolytic activity of C6-deficient sera with purified C6
restored also the release of 14C-AA and the
production of cytokines. Conclusion. In
vitro complement activation on the proximal tubular cell surface
triggers the generation of proinflammatory mediators, which may potentially
contribute to the pathogenesis of tubulointerstitial injury. 相似文献
2.
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4.
Pheochromocytoma and paraganglioma: comparison of MR imaging with CT and I-131 MIBG scintigraphy 总被引:6,自引:0,他引:6
To ascertain the magnetic resonance (MR) imaging characteristics of pheochromocytomas and paragangliomas and to compare MR with computed tomography (CT) and iodine-131 metaiodobenzylguanidine (I-131 MIBG), 19 patients (18 with pheochromocytomas, one with a paraganglioma) were studied. The 18 patients with pheochromocytomas had had positive findings with I-131 MIBG scintigraphy. Abdominal pheochromocytomas were generally hypointense compared with normal liver on T1-weighted MR images and extremely hyperintense on T2-weighted MR images. MR imaging was preferable to CT in the evaluation of primary pheochromocytomas due to superior tissue characterization, particularly in the patient with hypertension and borderline catecholamine levels. For patients with recurrent or metastatic disease, the data suggest that I-131 MIBG scintigraphy is the examination of choice. 相似文献
5.
IR. B. J. Hartog D. H. Liem 《Pharmacy World & Science》1981,3(1):273-283
Conclusie De verscheidenheid aan conserveermiddelen die in cosmetica worden toegepast, is zeer groot. Het is wenselijk het gebruik van deze verbindingen zo beperkt mogelijk te houden in verband met ongewenste bijwerkingen voor de gebruikers. Een effectieve conservering van produkten, waarin micro-organismen goed kunnen groeien, is echter noodzakelijk. Deskundige microbiologische begeleiding bij de ontwikkeling en fabricage van cosmetische produkten is dan ook essentieel.
Voordracht gehouden tijdens het symposium Conserveermiddelen op 13 november 1980 te Rotterdam.
Dit artikel wordt gelijktijdig geplaatst in De Waren Chemicus. 相似文献
Voordracht gehouden tijdens het symposium Conserveermiddelen op 13 november 1980 te Rotterdam.
Dit artikel wordt gelijktijdig geplaatst in De Waren Chemicus. 相似文献
6.
Emanuele D’Amico Silvia Messina Cinzia Caserta Francesco Patti 《Expert opinion on drug safety》2015,14(7):1157-1168
Introduction: Daclizumab (DAC) is a mAb that binds to CD25, a receptor on the surface of lymphocytes for IL-2, a chemical messenger in the immune system. This prevents activation and proliferation of lymphocytes, which are involved in the immune attack in multiple sclerosis (MS).Areas covered: In this review, we will focus on newly emerging DAC-high-yield process (HYP) therapy for MS. Based on published original articles and citable meeting abstracts, we will discuss its mode of action as well as data on efficacy and safety.Expert opinion: DAC has been observed to have multiple (biological) effects, which may contribute to beneficial effects in immune-related disease and particularly in relapsing-remitting MS. The positive results in the clinical studies represent achievement of an important milestone in the development of DAC-HYP as a potential new treatment option for MS patients. The benefit/risk ratios of this new biological agent in MS therapy are still being evaluated. Soon, DAC-HYP might qualify as MS therapy. A safety monitoring program is recommended in the clinical practice. 相似文献
7.
Inhibition of heparanase-mediated degradation of extracellular matrix heparan sulfate by non-anticoagulant heparin species 总被引:12,自引:0,他引:12
Incubation of human platelets, human neutrophils, or highly metastatic mouse lymphoma cells with sulfate-labeled extracellular matrix (ECM) results in heparanase-mediated release of labeled heparan sulfate cleavage fragments (0.5 less than Kav less than 0.85 on Sepharose 6B). This degradation was inhibited by native heparin both when brought about by intact cells or their released heparanase activity. Degradation of heparan sulfate in ECM may facilitate invasion of normal and malignant cells through basement membranes. The present study tested the heparanase inhibitory effect of nonanticoagulant species of heparin that might be of potential use in preventing heparanase mediated extravasation of bloodborne cells. For this purpose, we prepared various species of low-sulfated or low-mol-wt heparins, all of which exhibited less than 7% of the anticoagulant activity of native heparin. N-sulfate groups of heparin are necessary for its heparanase inhibitory activity but can be substituted by an acetyl group provided that the O-sulfate groups are retained. O-sulfate groups could be removed provided that the N positions were resulfated. Total desulfation of heparin abolished its heparanase inhibitory activity. Heparan sulfate was a 25-fold less potent heparanase inhibitor than native heparin. Efficiency of low-mol-wt heparins to inhibit degradation of heparan sulfate in ECM decreased with their main molecular size, and a synthetic pentasaccharide, representing the binding site to antithrombin III, was devoid of inhibitory activity. Similar results were obtained with heparanase activities released from platelets, neutrophils, and lymphoma cells. We propose that heparanase inhibiting nonanticoagulant heparins may interfere with dissemination of bloodborne tumor cells and development of experimental autoimmune diseases. 相似文献
8.
Coppola L Caserta F Grassia A Mastrolorenzo L Altrui L Tondi G Verde S Coppola A 《Archives of gerontology and geriatrics》2002,35(1):27-34
Urinary incontinence is a common problem in older subjects, very often wrongfully accepted as a normal part of the aging process. A total of 520 subjects (208 males and 312 females; mean age 74.8 +/- 11.8 years), from both private- and nursing-home dwelling populations, were included in this study aimed to estimate the incidence of urinary incontinence and identify factors associated with condition, in aged subjects. The incidence and type of urinary incontinence (stress, urge or mixed incontinence) were assessed by structured questionnaires and diagnosis was confirmed by a seven-day consecutive voiding diary. Assessment of physical, cognitive and emotional functions was performed on each subject using the Mini Mental State Examination (MMSE), Instrumental Activities of Daily Living Scale (IADL), Tinetti Scale (gait), Tinetti Scale (balance) and Geriatric Depression Scale (GDS) instruments. In the total population sample the incidence of urinary incontinence was 47.9%. The incontinence cases were classified, according to the different types, as: stress incontinence (males: 3.4%; females: 8.7%; males+females: 6.5%); urge incontinence (males: 27.4%; females: 31.4%; males+females: 29.8%); mixed incontinence (males: 20.2%; females: 5.8%; males+females: 11.5%). In the total population sample, no significant relationship was found between age and prevalence of urinary incontinence. In the elderly female group, age significantly correlated in a direct manner with urge incontinence (P<0.01) and inversely with stress incontinence (P<0.001). Only in the male sex group age significantly correlated with mixed incontinence (P<0.005). Multiple linear regression analysis showed that the dependent variable 'incontinence' could be predicted by MMSE (P<0.001) in the male sex group and by the Tinetti Scale (gait) (P<0.001) in the female sex group. 相似文献
9.
Biological evaluation of intervertebral disc cells in different formulations of gellan gum‐based hydrogels 下载免费PDF全文
G Khang SK Lee HN Kim J Silva‐Correia ME Gomes CAA Viegas IR Dias JM Oliveira RL Reis 《Journal of tissue engineering and regenerative medicine》2015,9(3):265-275
Gellan gum (GG)‐based hydrogels are advantageous in tissue engineering not only due to their ability to retain large quantities of water and provide a similar environment to that of natural extracellular matrix (ECM), but also because they can gelify in situ in seconds. Their mechanical properties can be fine‐tuned to mimic natural tissues such as the nucleus pulposus (NP). This study produced different formulations of GG hydrogels by mixing varying amounts of methacrylated (GG‐MA) and high‐acyl gellan gums (HA‐GG) for applications as acellular and cellular NP substitutes. The hydrogels were physicochemically characterized by dynamic mechanical analysis. Degradation and swelling abilities were assessed by soaking in a phosphate buffered saline solution for up to 170 h. Results showed that as HA‐GG content increased, the modulus of the hydrogels decreased. Moreover, increases in HA‐GG content induced greater weight loss in the GG‐MA/HA‐GG formulation compared to GG‐MA hydrogel. Potential cytotoxicity of the hydrogel was assessed by culturing rabbit NP cells up to 7 days. An MTS assay was performed by seeding rabbit NP cells onto the surface of 3D hydrogel disc formulations. Viability of rabbit NP cells encapsulated within the different hydrogel formulations was also evaluated by Calcein‐AM and ATP assays. Results showed that tunable GG‐MA/HA‐GG hydrogels were non‐cytotoxic and supported viability of rabbit NP cells. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
10.