Search results for "complement"
showing 10 items of 2113 documents
Studies on the mechanism of PMN activation. I. By dextran sulfates.
1982
Evidence is presented that enhanced reduction of the dye nitroblue-tetrazolium (NBT) by polymorphonuclear leukocytes (PMN) which are stimulated by dextran sulfates (DS) is not exclusively due to the phagocytosis of particles formed by NBT and DS. Not only the size of phagocytizable particles but the degree of substitution determines the acceleration of NBT-reduction. A likely cause of this acceleration is the triggering of the alternative pathway of the complement activation.
Drimane-type Sesquiterpene Coumarins from Ferula gummosa Fruits Enhance Doxorubicin Uptake in Doxorubicin-resistant Human Breast Cancer Cell Line
2014
ABSTRACT Multidrug resistance (MDR) is the main cause of failure in the chemotherapy of cancer patients. The present study aimed to evaluate the effects of sesquiterpene coumarins of Ferula gummosa fruits on P-glycoprotein (P-gp)–mediated MDR. Drimane-type sesquiterpene coumarins from the fruits of F. gummosa were extracted with dichloromethane and subjected to column chromatography. The effects of the isolated compounds on P-gp–mediated MDR were evaluated in the breast cancer cell line MCF-7 which shows high resistance to doxoribicin (MCF-7/Dox). Phytochemical investigation of dichloromethane extract of F. gummosa fruits resulted in three sesquiterpene coumarins including conferone (1), mo…
C1q secreted in the tumour microenvironment promotes tumour growth in the absence of complement activation
2012
We have recently shown that locally secreted C1q is involved in trophoblast invasion of decidua during pregnancy (Agostinis et al., J. Immunol. 2010;185;4420–4429). Since this physiologic process resembles to some extent tumor progression, we sought to investigate if C1q plays a similar role in tumor development and progression. Immunohistochemical analysis of several solid tumours including colon, prostate, lung and breast cancer and melanoma revealed the presence of C1q that was localized on the vascular endothelium and also distributed in the stroma in the absence of C4. To investigate the in vivo role of C1q in tumour development, 6/8 week old female WT and C1q−/− C57BL/6 mice received …
Binding and activation of human and mouse complement by Cryptosporidium parvum (Apicomplexa) and susceptibility of C1q- and MBL-deficient mice to inf…
2008
Cryptosporidium parvum is a protozoan parasite (Apicomplexa) that causes gastrointestinal disease in animals and humans. Whereas immunocompetent hosts can limit the infection within 1 or 2 weeks, immunocompromised individuals develop a chronic, life-threatening disease. The importance of the adaptive cellular immune response, with CD4+ T-lymphocytes being the major players, has been clearly demonstrated. Several non-adaptive immune mechanisms have been suggested to contribute to the host defence, such as interferon-gamma (IFN-gamma) from NK cells, certain chemokines, beta-defensins and pro-inflammatory cytokines, but the influence of the complement systems has been less well studied. We ana…
The eighth component of human complement: molecular basis of C8A (C81) polymorphism.
1995
Using an exon-specific polymerase chain reaction (PCR) followed by direct DNA sequence analysis we have analyzed the polymorphism of the alpha-chain of the eighth component of human complement (C8) at the DNA level. We found that two common alleles, C8A*A and C8A*B, are characterized by the substitution of a single amino acid (Gln to Lys), which is caused by a point mutation of a single nucleotide (C to A) in exon 3 at position 187 of the mature C8 alpha cDNA sequence. Based on this mutation, an allele-specific PCR was designed detecting the two alleles of C8A. We applied this method to type the C8A polymorphism using DNA samples from a Chinese Han population. The comparison with the data o…
European and Chinese Cognitive Styles and Their Impact on Teaching Mathematics
2010
A General Framework and Theoretical References.- The Chinese Written Language as Tool for a Possible Historical and Epistemological Reflections on the Mathematics and the Impact of Teaching/Learning of Mathematics.- The Meta-rules between Natural Language and History of Mathematics.- Common Sense and Fuzzy Logic.- The Experimental Epistemology as a Tool to Observe and Preview Teaching/Learning Phenomena.- Strategy and Tactics in the Chinese and European Culture: Chess and Weich'i.- Rhythm and Natural Language in the Chinese and European Culture.- Conclusions.
TAKING A LOOK AT CHINESE PEDAGOGY IN SHUXUE [MATHEMATICS]: A DIALOGUE BETWEEN CULTURES TO APPROACH ARITHMETIC AT FIRST AND SECOND ITALIAN PRIMARY CLA…
2013
The purpose of this paper is to analyze two cases of task design about straws and word problems in different cultural traditions (the Eastern and Western one). By means of two paradigmatic examples developed in Italy, we aim at showing, on the one hand, the effects and advantages of intercultural dialogue and, on the other hand, the need to take into account and to respect culturally rooted pedagogies, avoiding uncritical transfer from one culture to another. This perspective implies a reciprocal respect of the different approach modalities and hence a continuous back and forth between the practical and the deeply related theoretical dimension
Can we learn from “outside”? A dialogue with a Chinese teacher: the “two basics” as a meaningful approach to mathematics teaching
2015
Since many years Confucian heritage students (Chinese ones in particular), acquire leading positions in numerous international scientific programmes and display excellent performance in international assessments as PISA or TIMMS (OECD, 2013). To understand the “reasons” of this excellence we tried to explore some aspects of the cultural background of teaching practices and classroom life in those countries. With this aim a Chinese teacher was interviewed; we asked him about principles, values and beliefs and their impact on teaching/learning Math in classroom. The paper discusses what emerged from this dialogue and in particular from the idea of the “Two Basics” mathematics teaching approac…