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1.
Effects of atrial natriuretic factor on human platelet function 总被引:1,自引:0,他引:1
We examined the hypothesis that atrial natriuretic factor (ANF), a substance with known vasorelaxant activities, shares with other vasodilators the property of inhibiting platelet function. Aggregation of citrated platelet-rich plasma (PRP) from 23 healthy volunteers induced by ADP, adrenaline, arachidonic acid, collagen, gamma-thrombin, the endoperoxide analogue U-44069, serotonin, the calcium ionophore A-23187 or platelet aggregating factor was measured after incubation of PRP with ANF for 3 minutes at concentrations of 4 X 10(-9), 4 X 10(-8) and 4 X 10(-7) M or vehicle as control. ANF decreased ADP-induced aggregation significantly (P less than 0.02), but only at the highest concentration used and to a minor extent (control: 73.6 +/- 11.2%; after ANF 4 X 10(-7) M: 60.0 +/- 17.1%, mean +/- S.D., n = 39) by a selective inhibitory effect on the secondary wave; neither aggregation by all other agents tested nor thromboxane B2 generation induced by ADP and adrenaline was altered by incubation with ANF. Although ANF thus has detectable effects on ADP-induced platelet aggregation in vitro, these data suggest that ANF is unlikely to be a physiologically significant modulator of platelet function. 相似文献
2.
Transfer factor in chronic mucocutaneous candidiasis 总被引:3,自引:0,他引:3
Fifteen patients suffering from chronic mucocutaneous candidiasis were treated with an in vitro produced TF specific for Candida
albicans antigens and/or with TF extracted from pooled buffy coats of blood donors. CMI of the patients was assessed using
the LMT and the LST in presence of candidine. The aim of the study was the clinical evaluation of TF treatment and the incidence
of positive tests before, during, and after therapy. Immunological data were matched using the Chi square test. 87 LMT were
performed for each antigen dose and at the dilution of 1/50, 58.9% (33/56) tests were positive during non-treatment or non-specific
TF treatment. On the contrary 83.9% (26/31) were positive during specific TF treatment (P<0.05). In the LST, a significant
decrease of thymidine uptake in the control cultures in presence of autologous or AB serum was observed when patients were
matched according to non-treatment, and both non specific (P<0.05) and specific TF treatment (P<0.01). Only during specific
TF treatment was a significant increase of reactivity against the Candida antigen at the highest concentration noticed, when
compared with the period of non specific treatment (P<0.01). Clinical observations were encouraging: all but one patient experienced
significant improvement during treatment with specific TF. These data confirm that orally administered specific TF, extracted
from induced lymphoblastoid cell-lines, increases the incidence of reactivity against Candida antigens in the LMT. LST reactivity
appeared not significantly increased with respect to the periods of non treatment, but was significantly increased when it
was compared to the non-specific TF treatment periods. At the same time, a clinical improvement was noticed. 相似文献
3.
A preliminary report on the use of transfer factor for treating stage D3 hormone-unresponsive metastatic prostate cancer 总被引:4,自引:0,他引:4
Dr. Giancarlo Pizza Caterina De Vinci Diego Cuzzocrea Domenico Menniti Ernesto Aiello Paolo Maver Giuseppe Corrado Piero Romagnoli Ennio Dragoni Giuseppe LoConte Umberto Riolo Aldopaolo Palareti Paolo Zucchelli Vittorio Fornarola Dimitri Viza 《Biotherapy》1996,9(1-3):123-132
As conventional treatments are unsuccessful, the survival rate of stage D3 prostate cancer patients is poor. Reports have
suggested the existence of humoral and cell-mediated immunity (CMI) against prostate cancer tumour-associated antigens (TAA).
These observations prompted us to treat stage D3 prostate cancer patients with an in vitro produced transfer factor (TF) able
to transfer, in vitro and in vivo, CMI against bladder and prostate TAA. Fifty patients entered this study and received one
intramuscular injection of 2–5 units of specific TF monthly. Follow-up, ranging from 1 to 9 years, showed that complete remission
was achieved in 2 patients, partial remission in 6, and no progression of metastatic disease in 14. The median survival was
126 weeks, higher than the survival rates reported in the literature for patients of the same stage. 相似文献
4.
Spartaco Santi Silvia Rubbini Caterina Cinti Stefano Squarzoni Alessandro Matteucci Elisabetta Caramelli Lia Guidotti Nadir M. Maraldi 《Biology of the cell / under the auspices of the European Cell Biology Organization》1994,81(1):47-57
Summary— In the sperm nuclei the DNA is packaged into a highly condensed form and is not organized into nucleosome and solenoid but is bound and stabilized mainly by the protamines that arrange the DNA in an almost crystalline state. As demonstrated for somatic cells, the sperm DNA has been reported to be organized in loop domains attached to the nuclear matrix structures. However, the possible role of the sperm head matrix in maintaining the loop organization in absence of a typical nucleosomal structures has not been fully elucidated. By using in situ nick translation at confocal and electron microscope level, we analyzed the organization of the DNAprotamine complex and its association with the sperm nuclear matrix. The data obtained indicate that the chromatin organization in sperm nuclei is maintained during the sperm condensation by means of interactions with the nuclear matrix at fixed sites. The fine stucture of sperm nucleus and of sperm nuclear matrix, investigated on sections and replicas of freeze-fractured specimens, suggests that the lamellar array, observed by freeze-fracturing in the sperm nuclei, could depend on the inner matrix which presents a regular organization of globular structures possibly involved in the maintenance of chromatin domains in highly condensed sperm nuclei also. 相似文献
5.
Cloning and functional characterization of LCR-F1: a bZIP transcription factor that activates erythroid-specific,human globin gene expression. 下载免费PDF全文
DNase I hypersensitive site 2 (HS 2) of the human beta-globin Locus Control Region (LCR) directs high level expression of the beta-globin gene located 50 kilobases downstream. Experiments in cultured cells and in transgenic mice demonstrate that duplicated AP1-like sites in HS 2 are required for this powerful enhancer activity. A cDNA clone encoding a basic, leucine-zipper protein that binds to these sites was isolated and designated Locus Control Region-Factor 1 (LCR-F1). This protein is a member of a new family of regulatory factors that contain a 63 amino acid ''CNC domain'' overlapping the basic region. This domain is approximately 70% identical in the Drosophila Cap N Collar (CNC) protein, NF-E2 and LCR-F1. LCR-F1 transactivates an HS 2/gamma-globin reporter gene over 170-fold in transient transfection experiments specifically in erythroid cells. These results suggest that LCR-F1 may be a critical factor involved in LCR-mediated, human globin gene expression. 相似文献
6.
Alfonso Pompella Caterina Cambiaggi Silvia Dominici Aldo Paolicchi Roberto Tongiani Mario Comporti 《Histochemistry and cell biology》1996,105(3):173-178
Confocal laser scanning fluorescence microscopy coupled to image analysis was employed in order to develop and evaluate procedures for the appraisal at the single-cell level of: (1) protein-bound 4-hydroxynonenal, the specific product of membrane peroxidation (by means of immunocytochemistry with biotin-avidin revelation); (2) protein oxidation (by reaction of protein carbonyls with 2,4-dinitrophenyl-hydrazine followed by immunocytochemistry of dinitrophenyl moieties); and (3) cellular protein thiols (by direct alkylation of sulfhydryl groups with thiol-specific fluorescent reagents possessing different cell permeabilities). The procedures proved able to reveal the subcellular distribution of cytochemical parameters useful as indices of oxidative stress conditions, and may allow redox phenotyping of isolated cells, which would provide an efficient tool in selected experimental models. 相似文献
7.
Giovanni Spinelli Marialuisa Melli Eva Arnold Caterina Casano Fabrizio Gianguzza Mirella Ciaccio 《Journal of molecular biology》1980,139(2):111-122
Sea urchin RNA extracted from early and mesenchyme blastula embryos and oocytes and fractionated on denaturing sucrose density gradients, was hybridized with histone DNA recombinants of Psammechinus miliaris (clone λh22) and of Paracentrotus lividus (clone pPH70). Histone sequences are found in the 9 S and larger than 9 S regions of the formamide/sucrose density gradients. The melting of the RNA-DNA duplexes obtained by hybridization of polysomal and high molecular weight RNA of embryos of P. lividus at the stage of early blastula, suggests a degree of heterogeneity in the high Mr RNA. The high Mr RNA contains at least four of the five histone gene sequences covalently linked. 相似文献
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10.
Viggiano E Passavanti MB Pace MC Sansone P Spaziano G Viggiano A Aurilio C Monda M Viggiano A Pota V De Luca B De Luca E 《Journal of cellular physiology》2012,227(5):1988-1991
Glutamine (gln) is the most abundant free amino acid in the blood. It is involved in important metabolic and biochemical processes, like cell proliferation and oxidative stress. Previous studies have demonstrated that gln concentration in human plasma decreases in several conditions such as sepsis, ischemia-reperfusion, trauma, major surgery and burn. The aim of the present work was to compare the acute effects of different types of surgical interventions and of anesthetization on blood gln concentration. Plasma samples from 88 subjects (30 males and 58 females) were collected before and after major or minor surgery and the gln concentration was analyzed with high-performance liquid chromatography. The results showed that plasma gln concentration after surgery was lower than pre-surgery values and that in major surgery the decrease of gln was higher than in minor surgery. No significant effect was shown for sex or type of anesthesia. These results demonstrate the importance of a gln supplementation before a surgical intervention and show that the amount of gln supplementation should also be adjusted based on the type of surgery. 相似文献