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81.
Background aimsMesenchymal stromal cells (MSC) possess immunomodulatory activity both in vitro and in vivo. However, little information is available regarding their function during the initiation of immunologic responses through their interactions with monocytes. While many studies have shown that MSC impair the differentiation of monocytes into dendritic cells and macrophages, there are few articles showing the interaction between MSC and monocytes and none of them has addressed the question of monocyte subset modulationMethodsTo understand better the mechanism behind the benefit of MSC infusion for graft-versus-host treatment through monocyte involvement, we performed mixed leucocyte reactions (MLR) in the presence and absence of MSC. After 3 and 7 days, cultures were analyzed by flow cytometry using different approachesResultsMSC induced changes in monocyte phenotype in an MLR. This alteration was accompanied by an increase in monocyte counting and CD14 expression. MSC induced monocyte alterations even without contact, although the parameters above were more pronounced with cell–cell contact. Moreover, the presence of MSC impaired major histocompatibility complex (MHC) I and II, CD11c and CCR5 expression and induced CD14 and CD64 expression on monocytes. These alterations were accompanied by a decrease in interleukin (IL)-1β and IL-6 production by these monocytes, but no change was observed taking into account the phagocytosis capacity of these monocytesConclusionsOur results suggest that MSC impair the differentiation of CD14++ CD16? CD64+ classical monocytes into CD14++ CD16+ CD64++ activated monocytes, having an even earlier role than the differentiation of monocytes into dendritic cells and macrophages.  相似文献   
82.
BackgroundSquamous cells are normally not found inside the breast. Therefore, a primary squamous cell carcinoma of the breast is an exceptional phenomenon and the management of this type of disease is still debated.AimClinical outcome assessment of a patient with squamous cell carcinoma of the breast.Materials and methodsWe report a case of primary squamous cell carcinoma of the breast (T1cN0M0) in a 51-years-old woman who underwent breast conserving surgery plus adjuvant chemotherapy and radiation therapy (RT).ResultsWith a follow up of 43 months, the patient is alive with no evidence of local or distant recurrence. The patient had Grade 2 acute skin toxicity. No late skin or respiratory toxicity was observed.ConclusionsPure primary squamous cell carcinoma of the breast is a rare and aggressive disease, often treatment-refractory. Our case shows that the addition of RT after breast conserving surgery, allows to achieve a high local control without adding severe toxicity. A multidisciplinary approach seems to be the optimal management for early stages in this rare disease.  相似文献   
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84.
Glutathione peroxidase (GPx) of mammalian cells and Escherichia coli formate dehydrogenase both contain a selenocysteine (SeCys) in their amino acid (aa) sequence. In these two enzymes, this aa is encoded by a UGA codon, which is usually a stop codon for protein synthesis. We constructed plasmids to test the synthesis of GPx in E. coli. These constructions permitted high-level production of GPx mutants, where the SeCys codon was replaced by cysteine (UGC, UGU) or serine (UCA) codons, but synthesis of selenoprotein could not be detected: our data suggest that signals used for the recognition of the UGA codon as a SeCys codon are not conserved between E. coli and mammalian cells.  相似文献   
85.
Staphylococcus aureus has emerged as a significant pathogen causing severe invasive disease in otherwise healthy people. Despite considerable advances in understanding the epidemiology, resistance mechanisms, and virulence factors produced by the bacteria, there is limited knowledge of the in vivo host immune response to acute, invasive S. aureus infections. Herein, we report that peripheral blood mononuclear cells from patients with severe S. aureus infections demonstrate a distinctive and robust gene expression profile which is validated in a distinct group of patients and on a different microarray platform. Application of a systems-wide modular analysis framework reveals significant over-expression of innate immunity genes and under-expression of genes related to adaptive immunity. Simultaneous flow cytometry analyses demonstrated marked alterations in immune cell numbers, with decreased central memory CD4 and CD8 T cells and increased numbers of monocytes. CD14+ monocyte numbers significantly correlated with the gene expression levels of genes related to the innate immune response. These results demonstrate the value of applying a systems biology approach that reveals the significant alterations in the components of circulating blood lymphocytes and monocytes in invasive S. aureus infections.  相似文献   
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87.
The Cre-loxP system is widely used for making conditional alterations to the mouse genome. Cre-mediated recombination is frequently monitored using reporter lines in which Cre expression activates a reporter gene driven by a ubiquitous promoter. Given the distinct advantages of fluorescent reporters, we developed a transgenic reporter line, termed IRG, in which DsRed-Express, a red fluorescent protein (RFP) is expressed ubiquitously prior to Cre-mediated recombination and an enhanced green fluorescent protein (EGFP) following recombination. Besides their utility for monitoring Cre-mediated recombination, we show that in IRG mice red and green native fluorescence can be imaged simultaneously in thick tissue sections by confocal microscopy allowing for complex reconstructions to be created that are suitable for analysis of neuronal morphologies as well as neurovascular interactions in brain. IRG mice should provide a versatile tool for analyzing complex cellular relationships in both neural and nonneural tissues.  相似文献   
88.
The utility of mammary prosthesis texturing in the prevention of capsular contracture was established some 20 years ago. Various models of implant texturing are currently on the market. We decided to study two of the most popular implants with two different surface texturings: the Biocell RTV and the Mentor 1600 Siltex. An observation at the electron microscopic level of the implants' surfaces was achieved. At the time of a prospective survey on 10 patients, the capsule fragments corresponding to these two prostheses have been analyzed at the electron microscopic level. All prostheses were removed from the patients because of asymmetry or bad positioning. The aim of our study was to establish a correlation between these two frequent texturing surfaces and their corresponding capsules. Our results showed that only the Biocell's capsules present a mirror image with correspondence of the depressions on the prosthesis and contacts on the capsule. This phenomenon seems linked to the existence of a critical size of the pores constituting the implant surface. This observation leads us to the hypothesis of an adhesive effect between the prosthesis and its capsule. If this last is not directly linked to the prevention of capsular contracture, it can have an effect on implant stabilization in the primary mammary reconstruction and in the secondary corrections of asymmetry or bad position.  相似文献   
89.
Two genomic tools for the study of Lepidoptera and the holocentric structure of their chromosomes are presented in this paper. A bacterial artificial chromosome (BAC) library was constructed using nuclear DNA partially digested with HindIII from eggs of Spodoptera frugiperda. The library contains a total of 36,864 clones with an average insert size of 125 kb, which corresponds to approximately 11.5 genome equivalents. Hybridization screening of the library was performed with eight single-copy genes, giving an average hit of 10 clones per marker gene. Colinearity between the genome and BACs was demonstrated at the triose phosphate isomerase (tpi) locus. Probing of the library with a PCR fragment internal to the 18S ribosomal gene allowed an estimation of the rDNA locus size close to 115 repeats per haploid genome. A new vector (pBAC3.6eGFP) for transient transfection into S. frugiperda cell lines has been constructed. It is based on the BAC vector, pBAC3.6e, in which a gene encoding GFP was inserted under the control of the densovirus P9 promoter. This vector has the advantage to accommodate large genomic inserts and to be transfected in a large lepidopteran host range. It was used to construct a second BAC library from Sf9 cell nuclear DNA in order to allow a comparison between somatic and cell line genome organization.  相似文献   
90.
Clones either strongly or barely expressing the Tn and Sialyl-Tn antigens were isolated from a rat colon carcinoma cell line. Expression of the antigens in normal rat tissues was very restricted and vaccination using Ovine Submaxillary Mucin as the immunogen could delay growth of the Sialyl-Tn positive cells, but not of the Sialyl-Tn negative cells in syngeneic rats. The model should be useful for testing new anti-Tn or Sialyl-Tn vaccination protocols.  相似文献   
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