Construction of micelles and hollow spheres the self-assembly behavior of poly(styrene-HPMI) copolymers with poly(4-vinylpyridine) derivatives mediated by hydrogen bonding interactions.

This study describes the preparation of hydrogen bonding connected micelles, consisting of a poly(styrene--(-hydroxyphenylmaleimide)) [poly(S--pHPMI)] core and a poly(4-vinylpyridine) (P4VP) derivative shell in a selective solvent. The aim was to modify hydrogen bonding interaction sites at the core/shell interface by synthesizing P4VP derivatives in three different sequences, namely, P4VP homopolymers, PS--P4VP random copolymers, and block copolymers. TEM images showed the successful self-assembly of poly(S--pHPMI)/PS--P4VP inter-polymer complexes into spherical structures.

Intra- and Intermolecular Hydrogen Bonding in Miscible Blends of CO/Epoxy Cyclohexene Copolymer with Poly(Vinyl Phenol).

In this study, we synthesized a poly(cyclohexene carbonate) (PCHC) through alternative ring-opening copolymerization of CO with cyclohexene oxide (CHO) mediated by a binary LZnOAc catalyst at a mild temperature. A two-dimensional Fourier transform infrared (2D FTIR) spectroscopy indicated that strong intramolecular [C-HO=C] hydrogen bonding (H-bonding) occurred in the PCHC copolymer, thereby weakening its intermolecular interactions and making it difficult to form miscible blends with other polymers. Nevertheless, blends of PCHC with poly(vinyl phenol) (PVPh), a strong hydrogen bond donor, were miscible because intermolecular H-bonding formed between the PCHC C=O units and the PVPh OH units, as evidenced through solid state NMR and one-dimensional and 2D FTIR spectroscopic analyses.

Meso/Microporous Carbons from Conjugated Hyper-Crosslinked Polymers Based on Tetraphenylethene for High-Performance CO Capture and Supercapacitor.

In this study, we successfully synthesized two types of meso/microporous carbon materials through the carbonization and potassium hydroxide (KOH) activation for two different kinds of hyper-crosslinked polymers of TPE-CPOP1 and TPE-CPOP2, which were synthesized by using Friedel-Crafts reaction of tetraphenylethene (TPE) monomer with or without cyanuric chloride in the presence of AlCl as a catalyst. The resultant porous carbon materials exhibited the high specific area (up to 1100 m g), total pore volume, good thermal stability, and amorphous character based on thermogravimetric (TGA), N adsoprtion/desorption, and powder X-ray diffraction (PXRD) analyses. The as-prepared TPE-CPOP1 after thermal treatment at 800 °C (TPE-CPOP1-800) displayed excellent CO uptake performance (1.

Synthesis of Sodium Complexes Supported with NNO-Tridentate Schiff Base Ligands and Their Applications in the Ring-Opening Polymerization of L-Lactide.

A series of sodium complexes bearing NNO-tridentate Schiff base ligands with an N-pendant arm were synthesized and used as catalysts for the ring-opening polymerization of L-lactide (L-LA). Electronic effects of ancillary ligands coordinated by sodium complexes substantially influence the catalysis, and ligands with electron-donating groups increase the catalytic activity of the sodium complexes for catalyzing L-LA polymerization. In particular, a sodium complex bearing a 4-methoxy group has the highest activity with conversion up to 95% within 30 s at 0 °C and a low polydispersity index of 1.

IL-6 production stimulated by CD14(+) monocytes-paracrined IL-1β does not contribute to the immunosuppressive activity of human umbilical cord mesenchymal stem cells.

Background/aims: Human umbilical cord mesenchymal stem cells (hUC-MSCs) possess immunosuppressive activities but the mechanisms of such activities are not fully understood. Here, we investigated the role of IL-6, one of the characteristic factors of MSCs, in the immunoregulating effect of hUC-MSCs on CD4(+) T lymphocytes.

Methods: The condition media from human peripheral blood mononuclear cells (hPBMCs) or CD14+/- cell were tested if stimulating IL-6 production by hUC-MSCs.

Decreased expression of MBD2 and MBD4 gene and genomic-wide hypomethylation in patients with primary immune thrombocytopenia.

Genome-wide hypomethylation has been confirmed in patients with primary immune thrombocytopenia (ITP). Proteins containing methylcytosine-binding domain (MBD) are involved in promoter methylation as transcriptional repressors and promote the gene-silencing effect of DNA methylation. The purpose of this study was to investigate the methylation pattern of T cells and the relationship between genomic methylation and the expression of MBD2 and MBD4 in ITP patients.

[Construction and identification of a novel adeno-integrase hybrid system for hemophilia B].

This study was aimed to construct an adenovirus hybrid system with high transduction efficiency and site-specific integration. By a series of DNA manipulation, a hybrid system of two adenovirus vectors was constructed. One vector contains loxP-flanked transgene expression cassette, in which there are hFIX and DsRed coding sequences and attB for phiC31 recolonization.

CD14+ monocytes promote the immunosuppressive effect of human umbilical cord matrix stem cells.

Here, the effect of CD14(+) monocytes on human umbilical cord matrix stem cell (hUC-MSC)-mediated immunosuppression was studied in vitro. hUC-MSCs exerted a potent inhibitory effect on the proliferation and interferon-gamma (IFN-gamma) secretion capacities of CD4(+) and CD8(+) T cells in response to anti-CD3/CD28 stimulation. Transwell co-culture system revealed that the suppressive effect was primarily mediated by soluble factors.

Human umbilical cord mesenchymal stem cells hUC-MSCs exert immunosuppressive activities through a PGE2-dependent mechanism.

Human umbilical-cord-derived mesenchymal stem cells (hUC-MSCs) constitute an attractive alternative to bone-marrow-derived MSCs for potential clinical applications because of easy preparation and lower risk of viral contamination. In this study, both proliferation of human peripheral blood mononuclear cells (hPBMCs) and their IFN-gamma production in response to mitogenic or allogeneic stimulus were effectively inhibited by hUC-MSCs. Co-culture experiments in transwell systems indicated that the suppression was largely mediated by soluble factor(s).

Mesenchymal stem cells from bone marrow show a stronger stimulating effect on megakaryocyte progenitor expansion than those from non-hematopoietic tissues.

In order to evaluate whether mesenchymal stem cells (MSCs) from non-hematopoietic tissues are able to regulate megakaryocytopoiesis, we identified human MSCs from adult bone marrow (ABM), fetal pancreas (FPan) and umbilical cord (UC), and their abilities to support megakaryocyte (MK) differentiation from CD34(+) hematopoietic progenitor cells (HPCs) were comparatively studied. First, MSCs were isolated from ABM, FPan and UC then their growth kinetics, molecular characterization and mesodermal differentiation capacity were determined. ABM-MSCs, FPan-MSCs and UC-MSCs were irradiated and cocultured with human umbilical cord blood (UCB) CD34(+) cells, and the expansion efficiency of MK progenitor cells and MK formation were analysed and compared.

[Combined deficiency of factors V and VIII caused by a novel compound heterozygous mutation of gene Lman1].

Combined deficiency of factor V and VIII (F5F8D) is a rare, autosomal recessive disorder caused by mutations of either lman1 or mcfd2. To identify mutations of these two genes in a Chinese F5F8D family, the samples of peripheral blood were collected from the proband and her parents. Coagulation tests were carried out, including activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT), fibrinogen (Fg) and coagulate activity of FV, FVIII (FV:C, FVIII:C).

[Comparative study of in vitro hematopoietic supportive capability of human mesenchymal stem cells derived from bone marrow and umbilical cord].

The present study was aimed to isolate and identify human mesenchymal stem cells from adult bone marrow (BM-MSC) and umbilical cord (UC-MSC), and to compare their ability to support in vitro long-term hematopoiesis. MSC from bone marrow and umbilical cord were isolated by using density gradient centrifugation or enzyme digestion. MSC were further purified by adherent culture.

[Genetic analysis of an inherited afibrinogenemia family caused by a novel frameshift mutation in FGA].

Inherited afibrinogenemia is a rare autosomal recessive bleeding disease characterized by complete absence of fibrinogen in blood. To identify the genotype in a Chinese family with inherited afibrinogenemia, the samples of peripheral blood were collected from 6 members of 3 generations. The activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT) and fibrinogen (Fg, clauss) were tested.

[Analysis of complicated anemia in 60 patients with systemic lupus erythematosus].

The study was aimed to explore the characteristics of clinical manifestation, laboratory indicators and bone marrow examination of SLE patients with anemia. 60 SLE patients with anemia were analyzed for their clinical manifestation, laboratory indicators and bone marrow examination in comparison with 40 contemporaneous SLE patients without anemia. The results indicated that there were significant differences in clinical manifestations of fatigue between the SLE patients with anemia and those without anemia.

[Transfusion of allogeneic mesenchymal stem cells promotes progression of atherosclerotic plaque in rabbits].

The present study was purposed to evaluate the safety of mesenchymal stem cell (MSC)-based therapy impacting on atherosclerosis. Allogeneic MSCs were obtained from rabbit bone marrow aspirates and expanded in vitro. New Zealand white rabbits were divided into three groups: 24 rabbits with hypercholesterolemia receiving intravenous injection of either 5 x 10(7) MSCs (n = 12) or saline (n = 12) after 5 weeks on a high lipid diet and additional rabbits (n = 6) fed with standard rabbit diet were served as controls.

[Reversal of leukemia multidrug resistance by sequence-specific short hairpin RNA].

This study was aimed to design and screen short hairpin RNA (shRNA) molecules targeting multidrug resistance gene (mdr1), as well as to investigate the effects of shRNA expression vector on K562/A02 cells. Mdr1-shRNA expression vector was transfected into K562/A02 cells by lipofectamine 2000, and G418 was added to screen and establish the stable expression cell strain. The expressions of mdr1 mRNA and protein were detected by real-time RT-PCR and Western blot respectively.

Neural ganglioside GD2 identifies a subpopulation of mesenchymal stem cells in umbilical cord.

In contrast to hematopoietic stem cells, there is still a lack of definitive cell markers for specific isolation and identification of mesenchymal stem cells (MSCs). Thus a homogenous population of MSCs is only obtained after several passages, when multilineage potential or other distinctive features of very early progenitors may be already somewhat compromised. Recently a novel surface marker the neural ganglioside GD2 has been reported to distinguish MSCs from all other cells within marrow.

The role of T-cell immunoglobulin- and mucin-domain-containing molecule-3 polymorphisms in idiopathic thrombocytopenic purpura.

The family of T-cell immunoglobulin- and mucin-domain-containing molecules (TIMs) has an important role in immune regulation. TIM-3 is a transmembrane protein preferentially expressed on terminally differentiated Th1 cells and plays a role in T-helper (Th)-1-mediated autoimmune disease. Idiopathic thrombocytopenic purpura (ITP) is an acquired organ-specific autoimmune disease with a polarization of Th1.

[Neovascularization potential of mobilized peripheral mononuclear cells from diabetes patients].

Objective: To determine whether mobilized peripheral blood mononuclear cells (M-PBMNCs) obtained from patients with diabetes was impaired in therapeutic neovascularization in limb ischemia, and to explore the pathological mechanisms of the impairment.

Methods: Endothelial progenitor cells (EPC) were cultured in EGM-2MV, and then characterized by uptake of 1, 1-dioctadecyl-3, 3, 3, 3-tetramethylindocarbocyanine-labeled acetylated low density lipoprotein (Dil-AcLDL) and binding of ulex europaeus agglutinin (UEA). The number of EPC was compared between M-PBMNCs obtained from diabetic patients and those from normal subjects.

In vitro and in vivo differentiation of human umbilical cord derived stem cells into endothelial cells.

The successful use of tissue-engineered transplants is hampered by the need for vascularization. Recent advances have made possible the using of stem cells as cell sources for therapeutic angiogenesis, including the vascularization of engineered tissue grafts. The goal of this study was to examine the endothelial potential of human umbilical cord-derived stem (UCDS) cells.

Human umbilical cord derived stem cells for the injured heart.

The limited ability of the heart to regenerate damaged tissue following a myocardial infarct results in progressive dysfunctions and consequently leads to heart failure. Cell therapy with stem cells for cardiac repair is emerging as an alternative strategy and demonstrates promising results. Recent advances suggest human umbilical cord may be a new source for stem cells.