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Background  

Endometriosis is a common gynaecological disorder characterized by the presence of endometrial tissue outside of the uterus. The fragments in normal menstruation are composed of necrotic and living cells, which do not survive in ectopic locations because of programmed cell death. The aim of this study was to evaluate if the balance between cell proliferation and apoptosis is changed in eutopic endometrium from women with endometriosis throughout the menstrual cycle by studying bax (pro-apoptotic), c-myc (regulator of cell cycle) and TGF-beta1 (involved in cell differentiation) genes.  相似文献   

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Intravenously infused liposomes may induce cardiopulmonary distress in some human subjects, which is a manifestation of "complement activation-related pseudoallergy." We have now examined liposome-mediated complement activation in human sera with elevated lipoprotein (LDL and HDL) levels, since abnormal or racial differences in serum lipid profiles seem to modulate the extent of complement activation and associated adverse responses. In accordance with our earlier observations, cholesterol-rich (45 mol% cholesterol) liposomes activated human complement, as reflected by a significant rise in serum level of S-protein-bound form of the terminal complex (SC5b-9). However, liposome-induced rise of SC5b-9 was significantly suppressed when serum HDL cholesterol levels increased by 30%. Increase of serum LDL to levels similar to that observed in heterozygous familial hypercholesterolemia also suppressed liposome-mediated SC5b-9 generation considerably. While intravenous injection of cholesterol-rich liposomes into pigs was associated with an immediate circulatory collapse, the drop in systemic arterial pressure following injection of liposomes preincubated with human lipoproteins was slow and extended. Therefore, surface-associated lipoprotein particles (or apolipoproteins) seem to lessen liposome-induced adverse haemodynamic changes, possibly as a consequence of suppressed complement activation in vivo. PEGylated liposomes were also capable of activating the human complement system, and the presence of surface projected methoxypoly(ethylene glycol) chains did not interfere with generation of C3 opsonic fragments. We also show that poly(ethylene glycol) is not responsible for PEGylated liposome-mediated complement activation. The net anionic charge on the phosphate moiety of the phospholipid-mPEG conjugate seemed to play a critical role in activation of both the classical and alternative pathways of the complement system.  相似文献   

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Kaposi's sarcoma-associated human herpesvirus (KSHV) is thought to cause Kaposi's sarcoma, primary effusion lymphoma, and multicentric Castleman's disease. Previously, we reported that the KSHV complement control protein (KCP) encoded within the viral genome is a potent regulator of the complement system; it acts both as a cofactor for factor I and accelerates decay of the C3 convertases (Spiller, O. B., Blackbourn, D. J., Mark, L., Proctor, D. G., and Blom, A. M. (2003) J. Biol. Chem. 278, 9283-9289). KCP is a homologue to human complement regulators, being comprised of four complement control protein (CCP) domains. In this, the first study to identify the functional sites of a viral homologue at the amino acid level, we created a three-dimensional homology-based model followed by site-directed mutagenesis to locate complement regulatory sites. Classical pathway regulation, both through decay acceleration and factor I cleavage of C4b, required a cluster of positively charged amino acids in CCP1 stretching into CCP2 (Arg-20, Arg-33, Arg-35, Lys-64, Lys-65, and Lys-88) as well as positively (Lys-131, Lys-133, and His-135) and negatively (Glu-99, Glu-152, and Asp-155) charged areas at opposing faces of the border region between CCPs 2 and 3. The regulation of the alternative pathway (via factor I-mediated C3b cleavage) was found to both overlap with classical pathway regulatory sites (Lys-64, Lys-65, Lys-88 and Lys-131, Lys-133, His-135) as well as require unique, more C-terminal residues in CCPs 3 and 4 (His-158, His-171, and His-213) and CCP 4 (Phe-195, Phe-207, and Leu-209). We show here that KCP has evolved to maintain the spatial structure of its functional sites, especially the positively charged patches, compared with host complement regulators.  相似文献   

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The chirality of the title heterocycles is discussed considering their genesis by desymmetrization of the corresponding adamantanes. Some rules for the specification of the absolute configurations of the enantiomers (R or S) for this type of compounds are proposed. © 1996 Wiley-Liss, Inc.  相似文献   

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The neutrophil-stimulating activity of C. albicans before and after opsonization in the system of the alternative way of complement activation (AWCA) was studied. The study revealed that, in comparison with zymosan, C. albicans exhibited a considerably lower index of AWCA-dependent opsonic effect in reaction with neutrophils. This did not correlate with the capacity of substrates to activate the alternative cascade and with the intensity of phagocytosis. The suggestion on the involvement of C. albicans thermolabile cell-wall components into the negative regulation AWCA-dependent opsonic effect was substantiated.  相似文献   

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Various methods, including random regression, structured antedependence models, and character process models, have been proposed for the genetic analysis of longitudinal data and other function-valued traits. For univariate problems, the character process models have been shown to perform well in comparison to alternative methods. The aim of this article is to present an extension of these models to the simultaneous analysis of two or more correlated function-valued traits. Analytical forms for stationary and nonstationary cross-covariance functions are studied. Comparisons with the other approaches are presented in a simulation study and in an example of a bivariate analysis of genetic covariance in age-specific fecundity and mortality in Drosophila. As in the univariate case, bivariate character process models with an exponential correlation were found to be quite close to first-order structured antedependence models. The simulation study showed that the choice of the most appropriate methodology is highly dependent on the covariance structure of the data. The bivariate character process approach proved to be able to deal with quite complex nonstationary and nonsymmetric cross-correlation structures and was found to be the most appropriate for the real data example of the fruit fly Drosophila melanogaster.  相似文献   

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Complement control protein modules (CCP) typically mediate protein:protein interaction during immune response in vertebrates. Using NMR chemical shift perturbation mapping, we present previously lacking experimental evidence for intermolecular interactions between the CCP1 and CCP2 modules of the human C1r serine protease (SP). The identified interface is clearly distinct from that observed in the covalently linked CCP1-CCP2 pair. Structural models of the CCP1-CCP2-SP segments of two C1r molecules built on the basis of shift perturbation data are fully consistent with an extended interaction interface and suggests the possibility of a structural rearrangement as a switch between functional states of human C1r.

Structured summary

MINT-8045767: CCP1 (uniprotkb:P00736) and CCP2 (uniprotkb:P00736) bind (MI:0407) by nuclear magnetic resonance (MI:0077)  相似文献   

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For the all pairwise comparisons for equivalence of k (k≥2) treatments Lauzon and Caffo proposed simply to divide the type I error level α by k-1 to achieve a Bonferroni-based familywise error control when declaring pairs of two treatments equivalent. This rule is shown to be too liberal for k≥4. It works for k=3 yet for reasons not considered by Lauzon and Caffo. Based on the two one-sided testing procedures and using the closure test principle we develop valid alternatives based on Bonferroni's inequality. The set H of intersection hypotheses reveals a rich structure, leading to the possibility to present H as a directed acyclic graph (DAG). This in turn allows using some graph theoretical theorems and eases proving properties of the resulting multiple testing problems.  相似文献   

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The serum of patient suffering genetically conditioned C2 defect showed a weak bactericidal activity against Pseudomonas aeruginosa strains. Out of 23 tested strains one was susceptible comparing with 16 ones sensitive to normal human serum. The normal cord serum exerted a bactericidal effect on 8 strains. All sera were found to be active against Salmonella strains tested.  相似文献   

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Recent psychophysiological investigations have shown that biofeedback and operant conditioning procedures are associated with changes in genital vasomotor activity in men and women. Although the exact role played by biofeedback or operant contingencies in the establishment of genital vasomotor control has not been conclusively established, some degree of voluntary control has been reliably demonstrated over a response that is traditionally viewed as an involuntary component of the human sexual response cycle. The present article critically reviews the experimental literature pertinent to the issue of voluntary self-control of sexual responding and makes recommendations concerning future research. The implications of this literature for traditional etiological theories and treatment approaches for sexual dysfunctions are discussed. The potential of biofeedback and operant techniques for shaping genital responses, increasing discriminability, enhancing body awareness, and facilitating cognitive labeling of genital sensations are discussed as they relate to the stated goals of sex therapy.  相似文献   

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