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101.
Background/AimMultiple sclerosis (MS) is an inflammatory, demyelinating disease of the central nervous system. Effector T helper cells, mainly Th1 and Th17, cytotoxic T-cells, B-cells, macrophages, microglia, and the cytokines they secrete, are implicated in the initiation and maintenance of a deregulated immune response to myelin antigens and the ensuing immune-mediated demyelination. In this study, we investigated whether signature cytokines exist in MS patients at presentation to gain an insight into the underlying immunopathogenic processes at the early stage of the disease.MethodsWe collected serum and cerebrospinal fluid (CSF) samples from 123 patients at presentation, eventually diagnosed with MS or non-inflammatory (NIND) or inflammatory neurological diseases (IND) or symptomatic controls (SC). The levels of cytokines IFN-γ, TNF-α, TGF-β1, IL-2, IL-4, IL-6, IL-10 and IL-17 were measured, and cytokine ratios, such as Th1/Th2, Th1/Th17, and Type-1/Type-2, were calculated. All parameters were tested for their correlations with the intrathecal IgG synthesis.ResultsCytokine levels in CSF were lower than in serum in all the patients, with the exception of IL-6. Serum or CSF cytokine levels of MS patients did not differ significantly from NIND or SC, with the exception of serum IFN-γ and TNF-α that were significantly higher in NIND. IND patients presented with the highest levels of all cytokines in serum and CSF, with the exception of serum IL-10 and CSF IL-17. MS patients had a significantly lower serum Th1/Th2 ratio compared to the NIND and IND groups, and significantly lower serum Type-1/Type-2, IFN-γ/IL-10 and CSF Th1/Th17 ratios compared to IND patients. MS patients had a significantly higher CSF IL-17/IL-10 ratio compared to IND patients. The IgG index was higher in MS patients compared to the control groups; the differences reached statistical significance between the MS and the NIND and SC groups. Reiber-Felgenhauer analysis of the QIgG and QAlb indices revealed higher intrathecal IgG synthesis in MS patients, and higher blood-CSF barrier dysfunction in IND patients. The IgG index correlated with CSF IL-4 in MS patients only.ConclusionsWe found no signature cytokines or profiles thereof in MS patients at presentation. Only IND patients presented with a clear Th1 cytokine polarization in serum and CSF. The parameters that distinguished MS patients from patients with other neurological disorders were IgG intrathecal synthesis, the IgG index and its correlation with CSF IL-4 levels.  相似文献   
102.
Granulocyte colony-stimulating factor (G-CSF) plays an essential role in regulating multiple aspects of hematopoiesis. To elucidate the role of G-CSF in controlling hematopoietic cell migration capabilities, we studied inducible expression of the myeloid-specific marker, integrin alpha(M)beta(2) (CD11b/CD18, Mac-1), in the myeloid cell line, 32D. We found that G-CSF stimulates the synthesis and cell surface expression of alpha(M) and beta(2) integrin subunits. Induction of both alpha(M) and beta(2) is dependent on Stat3, a major G-CSF-responsive signaling protein. However, the kinetics of expression suggested the involvement of an intermediate protein regulated by Stat3. Our results demonstrate that Stat3 signaling stimulates the expression of PU.1, a critical regulator of myelopoiesis. Furthermore, we show that PU.1 is an essential intermediate for the inducible expression of alpha(M)beta(2) integrin. Thus, Stat3 promotes alpha(M)beta(2) integrin expression through its activation of PU.1. These findings indicate that G-CSF-dependent Stat3 signals stimulate the changes in cell adhesion and migration capabilities that occur during myeloid cell development. These data also demonstrate a link between Stat3 and PU.1, suggesting that Stat3 may play an instructive role in hematopoiesis.  相似文献   
103.
Two-dimensional (2D) gel electrophoresis and mass spectrometry (MS) have been used in comparative proteomics but inherent problems of the 2D electrophoresis technique lead to difficulties when comparing two samples. We describe a method (sub-proteome differential display) for comparing the proteins from two sources simultaneously. Proteins from one source are mixed with radiolabelled proteins from a second source in a ratio of 100:1. These combined proteomes are fractionated simultaneously using column chromatographic methods, followed by analysis of the pre-fractionated proteomes (designated sub-proteomes) using 2D gel electrophoresis. Silver staining and (35)S autoradiography of a single gel allows precise discrimination between members of each sub-proteome, using commonly available computer software. This is followed by MS identification of individual proteins. We have demonstrated the utility of the technology by identifying the product of a transfected gene and several proteins expressed differentially between two renal carcinoma proteomes. The procedure has the capacity to enrich proteins prior to 2D electrophoresis and provides a simple, inexpensive approach to compare proteomes. The single gel approach eliminates differences that might arise if separate proteome fractionations or 2D gels are employed.  相似文献   
104.
MbeA and MbeC are two key proteins in plasmid ColE1 conjugal mobilization. Isothermal titration calorimetry was used to detect and quantify an interaction between MbeA and MbeC. As a result of this interaction, the affinity of MbeA for single stranded DNA increased. The interaction was confirmed in vivo using a bacterial two-hybrid system, which revealed that MbeA-MbeC complexes are formed through the amino-terminal region of MbeA and the carboxy-terminal region of MbeC. To the best of our knowledge, this is the first report of direct interactions between conjugative proteins encoded by a mobilizable plasmid.  相似文献   
105.
Ventilation rate and turnover rate of dry air vary among different types of ventilation systems used with individually ventilated cages (IVCs) and can affect the well-being of rodents housed in these cages. The authors compared the effects of two types of IVC systems, forced-air IVCs and motor-free IVCs, on 4-week-old C57Bl/6J male mice. The mice were acclimatized to the cages for 8 d and then monitored for 87 d. Their body weights, food and water consumption and preferred resting areas were recorded. Mice that were housed in motor-free IVCs had a significantly greater increase in body weight than those housed in forced-air IVCs, despite having similar food consumption. Mice in forced-air IVCs had greater water consumption than mice in motor-free IVCs. In addition, mice in forced-air IVCs were more frequently located in the front halves of their cages, whereas mice in motor-free IVCs were located with similar frequency in the front and back halves of their cages, perhaps because of the higher ventilation rate or the location of the air inlets and outlets in the rear of the cage. These results suggest that body weight, food and water consumption and intracage location of growing male mice are influenced by the type of ventilation system used in the cages in which the mice are housed.  相似文献   
106.
107.
The agouti viable (Avy) locus is considered a model to understand how retroelements function as controlling elements in mammals. Epigenetic factors, principally CpG methylation, are widely held to play a dominant regulatory role in controlling the locus'' activity. The purpose of this study was to examine its behavior in ES cells and determine if this locus could be exploited for use in screen-based investigations. We have derived multiple Avy ES cell lines from the C57BL/6 strain and generated a cell line carrying a GFP-reporter gene (Avy/AGFP). Use of the DNA demethylating drug 5-azacitidine on various ES cell lines does not induce either agouti or GFP expression. Methylation analysis reveals that although most lines display normal methylation at IAP elements in general, the Avy IAP element is essentially unmethylated. In addition, we find that different repeat compartments are epigenetically unstable in a number of derived cell lines.  相似文献   
108.
109.

Objective

To determine if there is any non-linearity in the biomagnetic recordings of uterine myomas and to find any differences that may be present in the mechanisms underlying their signal dynamics.

Methods

Twenty-four women were included in the study. Sixteen of them were characterised with large myomas and 8 with small ones. Uterine artery waveform measurements were evaluated by use of Pulsatility Index (PI) (normal value PI<1.45).

Results

Applying nonlinear analysis to the biomagnetic signals of the uterine myomas, we observed a clear saturation value for the group of large ones (mean = 11.35 ± 1.49) and no saturation for the small ones.

Conclusion

The comparison of the saturation values in the biomagnetic recordings of large and small myomas may be a valuable tool in the evaluation of functional changes in their dynamic behavior.
  相似文献   
110.
Enteropathogenic Escherichia coli (EPEC) is a diarrhoeal pathogen that adheres to epithelial cells of the small intestine and uses a type III secretion system to inject effector proteins into host cells. EPEC infection leads to disruption of host intestinal tight junctions that are important for maintaining intestinal barrier function. This disruption is dependent on the bacterial type III secretion system, as well as the translocated effectors EspF and Map. Here we show that a third type III translocated bacterial effector protein, NleA, is also involved in tight junction disruption during EPEC infection. Using the drug Brefeldin A, we demonstrate that the effect of NleA on tight junction integrity is related to its inhibition of host cell protein trafficking through COPII-dependent pathways. These results suggest that NleA's striking effect on virulence is mediated, at least in part, via its role in disruption of intestinal barrier function.  相似文献   
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