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A positively charged tetraphenylethene (TPE) derivative, TPE-4MN, was synthesized as a probe for heparin based on aggregation induced emission. On the addition of 5.0 μg/mL of heparin, TPE-4MN showed an enhanced emission of about 10-fold. The change in fluorescence at 475 nm was linear over a range of heparin concentrations of 0-1.0 μg/mL with an R = 0.99988 and the limit of detection (LOD) was calculated to be 0.75 μg/mL. The mechanism of the detection was proven to be through an ion pairing interaction. TPE-4MN showed good selectivity for heparin over other types of polysaccharides and could easily distinguish heparin from heparan sulfate, a glycosaminoglycan having a similar structure to that of heparin., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background Aims: Mesenchymal stromal cells (MSC) have been shown to be a promising candidate for tissue regeneration and cancer therapy. However, their therapeutic potential against chemotherapy-induced side-effects remains unclear., Methods: We treated murine Lewis lung carcinoma (LLC) and xenograft human colon tumors with adriamycin (ADM) for 3 consecutive days followed by one intravenous (i.v.) injection of human umbilical cord (hUC) MSC for several cycles., Results: MSC treatment mitigated ADM-induced cardiomyopathy, reduced the extent of ADM-induced apoptosis in intestinal crypts, suppressed body weight loss in mice treated with ADM and increased the survival rate of mice treated with a lethal dose of ADM. The examination of hematologic parameters indicated a moderate recovery in MSC-injected mice. Systemic administration of MSC did not increase the growth of murine LLC cells and human colon carcinoma in vivo while it strongly inhibited the lung metastases of LLC cells., Conclusions: We evaluated the prophylactic and therapeutic action of hUC MSC on the chemotherapy agent ADM-induced side-effects in two different tumor models. Our observations suggest that MSC can be used as auxiliary means in chemotherapy for certain tumor types.

Background: There is no data that demonstrates what anaesthesia is suitable for patients who have a high risk of fat embolism syndrome (FES). We investigated the mortality rates of rats that received a half lethal dose (LD(50)) of fat by intravenous injection after induction of general or spinal anaesthesia., Methods: An LD(50) of fat for rats was determined by using a toxicological method. Three hundred and seventy five rats were randomly assigned to receive general anaesthesia (group GA, n=125), or spinal block (group SA, n=125), or no anaesthesia (group C, n=125). The rats were injected with the LD(50) of fat at 20 min after anaesthesia induction. The mortality rates were recorded at 2, 8, 12, and 24h after fat injection., Results: The LD(50) of fat was 0.706 ml/kg and its 95% CI was 0.622 ml/kg-0.801 ml/kg. The mortality rate was lower in the group GA than in the group SA (p<0.01), whilst there was no statistical difference between the group SA and the group C (p=0.442)., Conclusion: It is feasible to assess the efficacy of various treatments for FES by comparing the mortality rates of animals after injection of an LD(50) of fat. The mortality rate of rats was lower when FES was induced under general anaesthesia than under spinal anaesthesia which implies that general anaesthesia is superior to spinal anaesthesia for patients who have a high risk of FES., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The human Fcγ receptor (FcγR) system is composed of 2 opposing families, the activating FcγRs (FcγRI, FcγRIIa, and FcγRIII) and the inhibitory FcγR (FcγRIIb). The disturbed balance of the activating and inhibitory FcγRs has been implicated in the pathogenesis of many autoimmune diseases. In this study, the expression of FcγRs on monocytes was determined in 23 patients with primary immune thrombocytopenia (ITP) before and after high-dose dexamethasone (HD-DXM) treatment. The FcγRI expression was significantly higher in ITP patients and decreased after HD-DXM treatment. The ratio of FcγRIIa/IIb mRNA expression on monocytes was significantly higher in untreated patients than in healthy controls. After HD-DXM therapy, the ratio decreased and the increased expression of FcγRIIb mRNA and protein coincided with a remarkable decrease in the expression of FcγRIIa, FcγRI, and monocyte phagocytic capacity. There was no significant difference in FcγRIII expression on monocytes between patients and controls. In vitro cell-culture experiments showed that DXM could induce FcγRIIa and FcγRIIb expression in monocytes from ITP patients, with FcγRIIb at higher amplitudes. These findings suggested that the disturbed FcγR balance might play a role in the pathogenesis of ITP, and that HD-DXM therapy could shift monocyte FcγR balance toward the inhibitory FcγRIIb in patients with ITP.

CD4(+)CD25(+) regulatory T cells (Treg) play the critical role in maintenance of peripheral immune tolerance. However, the numbers of naturally occurring Treg (nTreg) that can be isolated from periphery are far too small to be clinically effective. The isolation and expansion of nTreg for treatment of autoimmune diseases encounter great difficulties. Whether autoantigen-specific Treg could be converted from CD4(+)CD25(-) T cells in patients with autoimmune diseases has not been reported. Here, we demonstrated that platelet glycoprotein (GP)-specific induced Treg (GP-iTreg) could be generated de novo from nonregulatory CD4(+)CD25(-)CD45RA(+) cells in patients with idiopathic thrombocytopenic purpura and induced both antigen-specific and linked suppression. GP-iTreg mediated regulatory effects via modulating the T cell-stimulatory capacity of dendritic cells. By investigating the gene expression profile of iTreg-modulated dendritic cells, we provided a genome-wide assessment of the changes induced by antigen-specific iTreg and identified that the Toll-like receptor, Notch and transforming growth factor-beta signaling pathways were related to the GP-specific tolerance, with the Toll-like receptor pathway being dominant. The findings in patients with idiopathic thrombocytopenic purpura will facilitate our understanding of the mechanisms of induction and maintenance of autoantigen-specific tolerance and highlight the considerable potential of antigen-specific iTreg for targeted immunotherapy in human auto-immune diseases.

Background: Platelet glycoprotein (GP)-reactive CD4+ T cells are essential for the stimulation and maintenance of antiplatelet autoantibody production in chronic idiopathic thrombocytopenic purpura (ITP). Blocking costimulatory signals could result in platelet-specific T-cell anergy., Methods: GP-specific CD4+ T cells from patients with ITP were made anergic using cytotoxic T-lymphocyte-associated antigen 4 immunoglobulin (CTLA4-Ig). The CTLA4-Ig-induced GP-specific anergic T cells were investigated for their inhibitory function on GP-reactive T-cell proliferation and antibody production with in vitro culture systems. To further analyze their tolerizing mechanisms, we cocultured GP-anergic T cells with dendritic cells (DCs) from patients with ITP., Results: Our studies demonstrated that the anergized GP-specific T cells have profound effects on both GP-specific T-cell proliferation and antibody production. These anergic T cells exerted their suppressive effects mainly in a cell contact-dependent manner, and they were not constitutively suppressive but required specific antigen stimulation to make DCs tolerogenic. The anergic T-cell-modulated DCs could induce the autoreactive T cells to be tolerant, and this effect was not restricted to T cells of the same specificity., Conclusion: Our studies demonstrate the efficacy of CTLA4-Ig in suppressing the pathologic autoimmune responses in ITP. These findings provide new insights into the underlying mechanisms of anergy induction in chronic ITP.

An ideal expression algorithm should be able to tell truly different expression levels with small false positive errors and be robust to assay changes. We propose two algorithms. PQN is the non-central trimmed mean of perfect match intensities with quantile normalization. DQN is the non-central trimmed mean of differences between perfect match and mismatch intensities with quantile normalization. The quantiles for normalization can be either empirical or theoretical. When array types and/or assay change in a study, the normalization to common quantiles at the probe set level is essential. We compared DQN, PQN, RMA, GCRMA, DCHIP, PLIER and MAS5 for the Affymetrix Latin square data and our data of two sets of experiments using the same bone marrow but different types of microarrays and different assay. We found the computation for AUC of ROC at affycomp.biostat.jhsph.edu can be improved.

We hypothesized that lymphoid organs within intestinal allografts contribute to their immunogenicity. Consistent with this hypothesis recipient T cells rapidly migrated to the lymph nodes and Peyer's patches of syngeneic and allogeneic intestinal grafts such that at 24 h approximately 50% of the lymphocytes isolated from donor lymphoid organs were of recipient origin. However, only in the lymphoid organs of allografts did recipient T cells display an activated phenotype, proliferate and produce IFNgamma. Rejection of allogeneic intestines lacking lymphoid organs was dramatically impaired in splenectomized, lymph node-deficient recipients compared to lymph node bearing, wild-type allogeneic intestines. This demonstrates the important role of donor lymphoid organs in the rejection process. Furthermore, recipient T cells proliferated more extensively and produced more IFNgamma in donor lymphoid organs than in recipient lymphoid organs, indicating that donor lymphoid organs play a dominant role in initiating the recipient anti-donor immune response following intestinal transplantation.

Objective: To evaluate the value of MR dynamic Gadolinium-enhanced fast multiplanar spoiled gradient-echo (FMPSPGR) and spin-echo (SE) T1-weighted fat-suppressed techniques in the diagnosis of pancreatic carcinoma., Methods: Eighteen cases of pancreatic carcinoma verified by surgical and pathologic results were examined by MR, and the MR sequences included SE T1WI, FSE T2WI, SE T1-weighted fat-suppressed and dynamic Gadolinium-enhanced FMPSPGR., Results: Of 18 pancreatic carcinomas, 10, 6, and 2 tumors showed respectively hypo-intensity, iso-intensity and hyper-intensity on SE T1WI, meanwhile, 8, 6, and 4 tumors displayed hyper-intensity, iso-intensity and hypo-intensity on FSE T2WI in comparison with the normal pancreatic tissue. All of the tumors showed hypo-intensity on SE T1-weighted fat-suppressed and also obvious non-enhancement or slight enhancement on MR dynamic Gadolinium-enhanced FMPSPGR images during the arterial dominant phase scanning., Conclusion: SE T1-weighted fat-suppressed and MR dynamic Gadolinium-enhanced FMPSPGR sequences could evidently improve the sensitivity and specificity in the diagnosis of pancreatic carcinoma.

The import of subunit VII, the so-called ubiquinol binding protein of the cytochrome bc1 complex of yeast mitochondria, has been investigated by subcloning the gene for subunit VII into the expression vector pSP64. The precursor to subunit VII synthesized in vitro by a transcription/translation system had the same molecular weight as the mature form of this protein present in mitochondria, confirming earlier reports that subunit VII does not contain a cleavable presequence. The subunit VII precursor was imported efficiently into a protease-resistant compartment of isolated yeast mitochondria in a reaction dependent upon a membrane potential and the presence of ATP both in the mitochondrial matrix and in the extramitochondrial space. After import, the radiolabeled subunit VII was bound to the mitochondrial inner membrane through protein-protein interactions and could not be detected in the matrix fraction or in the intermembrane space. Subunit VII was also imported into mitoplasts, where the protein was associated with the inner membrane facing the matrix side of the membrane. By contrast, after import into mitochondria obtained from yeast cells lacking cytochrome b, subunit VII was localized in the supernatant fraction, suggesting that the presence of cytochrome b may be required for the association of subunit VII with the inner mitochondrial membrane.