Thienoisoindigo (TII)-Based Quinoidal Small Molecules for High-Performance n-Type Organic Field Effect Transistors.

A novel quinoidal thienoisoindigo (TII)-containing small molecule family with dicyanomethylene end-capping units and various alkyl chains is synthesized as n-type organic small molecules for solution-processable organic field effect transistors (OFETs). The molecular structure of the 2-hexyldecyl substituted derivative, TIIQ-b16, is determined via single-crystal X-ray diffraction and shows that the TIIQ core is planar and exhibits molecular layers stacked in a "face-to-face" arrangement with short core intermolecular distances of 3.28 Å. The very planar core structure, shortest intermolecular N···H distance (2.52 Å), existence of an intramolecular non-bonded contact between sulfur and oxygen atom (S···O) of 2.80 Å, and a very low-lying LUMO energy level of -4.16 eV suggest that TIIQ molecules should be electron transporting semiconductors. The physical, thermal, and electrochemical properties as well as OFET performance and thin film morphologies of these new TIIQs are systematically studied. Thus, air-processed TIIQ-b16 OFETs exhibit an electron mobility up to 2.54 cm2 V-1 s-1 with a current ON/OFF ratio of 105-106, which is the first demonstration of TII-based small molecules exhibiting unipolar electron transport characteristics and enhanced ambient stability. These results indicate that construction of quinoidal molecule from TII moiety is a successful approach to enhance n-type charge transport characteristics.

Attenuating spinal cord injury by conditioned medium from human umbilical cord blood-derived CD34⁺ cells in rats.

OBJECTIVE: Intravenous or intraspinal transplantation of human umbilical cord blood cells-derived CD34(+) cells (human CD34(+) cells) or mesenchymal stem cells after spinal cord injury (SCI) improved hind limb functional recovery in adult rats. The objective of this study is to ascertain whether SCI in rats can be attenuated by conditioned medium (CM) or secretome obtained from cultured human CD34(+) stem cells. MATERIALS AND METHODS: Sprague-Dawley rats were assigned to one of the following five groups: the sham group, the SCI group treated with vehicle solution (SCI + V), the SCI group treated with CM (SCI + CM), the SCI group treated with 17ß-estradiol E2 (10 µg; SCI + E2), and the SCI group treated with CM plus E2 (SCI + CM + E2). A 0.5-mL volume of CM or vehicle solution was administered intravenously immediately after SCI. RESULTS: Compared with the sham group, the (SCI + V) group had significantly higher scores of neurological motor dysfunction as well as inflammation apoptosis, oxidative stress, and astrogliosis in the injured spinal cord. The neurological deficits, numbers of apoptotic cell, extent of inflammation, oxidative stress, and astrogliosis in the injured spinal cord were significantly attenuated by CM, E2, or CM plus E2, but not by the vehicle solution. In addition, the neuroprotective effect exerted by a combination of CM and E2 is superior to that exerted by CM- or E2-alone therapy. CONCLUSION: The neuroprotective effects of CM from cultured human CD34(+) cells are similar to those of human CD34(+) cells and the CM was found to enhance the neuroprotective effects of E2 in rat SCI.

Selective Criteria and Markers in Adipose-Derived Stromal Cells Collection Quality and Expansion Potency.

BACKGROUND: Adipose tissue-derived stromal cells (ADSCs) have been extensively used in clinical trials for various therapeutic applications. However, there is a paucity of selective criteria regarding collection and expansion procedures. The purpose of this study was to investigate the effect of liposuction and donor age on ADSCs and to assess the criteria and markers for ADSC long-term expansion potential. METHODS: Adipose tissues were collected using syringe liposuction, water-jet, or ultrasonic techniques. Tissue/cell viability was evaluated using the XTT assay. CD34 and SSEA-4 expression were examined using flow cytometry. SOX2 gene expression was estimated using quantitative polymerase chain reaction, and Nile-red staining was performed to evaluate the adipogenesis potency during ADSC expansion. RESULTS: The lipoaspirates obtained from syringe and ultrasonic liposuction methods were superior to those of the water-jet method in stromal vascular fraction yield and durability during temporary storage. SSEA-4, SOX2 expression, and adipogenesis potency of early-passage ADSCs were significantly correlated with the P15 cumulative population doublings data. CD34 expression was strongly correlated with P0 ADSC yield and doubling time. Tissue viability, P0 ADSC CD34⁺ percentage, and P15 cumulative population doublings were decreased along with donor age. CONCLUSIONS: This study established criteria and markers to determine whether lipoaspirate tissue and cultured ADSCs are suitable for further large-scale expansion and allogenic universal cell banking.

Time-Series Expression of Toll-Like Receptor 4 Signaling in Septic Mice Treated with Mesenchymal Stem Cells.

Sepsis remains an important cause of mortality worldwide, and early deaths resulting from overwhelming inflammation in septic patients have been reported. Vigorous immune reactions are beneficial for bacterial clearance in this circumstance but at the price of self-tissue damage. Mesenchymal stem cells (MSCs) have been found to modulate immune function and attenuate sepsis. As the Toll-like receptor 4 pathway plays an important role in response to infections, here we investigated the mechanisms of MSC-mediated immunomodulation by determining the expression of Toll-like receptor 4 signaling in the liver and by circulating cytokines at 0, 1, 2, 3, and 6 h after cecal ligation and puncture (CLP)-induced sepsis in mice. We found that administration of umbilical cord-derived MSCs (UCMSCs) was beneficial for survival. Six hours after CLP, UCMSC administration decreased the expression of MyD88 mRNA and protein in the liver tissues of the mice, and also the ratio of NFκB phosphorylation (P = 0.041 and 0.005, respectively). Serum levels of TNF-α, MCP-1, IFN-γ, and IL-6 were significantly lower and IL-10 significantly higher 6 h after CLP in the mice receiving UCMSCs compared with those receiving PBS only. Our study provides the first in vivo evidence for the association of the MyD88-NFκB pathway and MSC-mediated immunomodulation during sepsis. The immunomodulatory effect of UCMSCs was noted from 3 to 6 h after injection, and the MyD88-NFκB pathway played an important role in response to the immunomodulatory signals from UCMSCs.

Physiology and potential application of NKT cells: a minireview.

CD1d-restricted T (NKT) cells are potent regulators of autoimmunity, tumor immunity, and transplantation-related immunity. NKT cells are a subset of innate lymphocytes that recognize endogenous or exogenous glycolipids in the context of CD1d molecules. Recent progress in the research of NKT cells has proved that NKT cells function as a bridge between innate and adaptive immunity in anticancer immunity. Furthermore, NKT cells also function as a bridge to tolerance or rejection of grafts in organ transplantation. Harnessing the function of NKT cells, and trying to put it into clinical application in the treatment of autoimmune disease, anticancer cell immunotherapy, and organ transplantation are the dreams of immunologists. This minireview will focus on the physiology of NKT cells and potential clinical application.

Hepatocyte growth factor gene therapy prevents radiation-induced liver damage.

AIM: To transfer human HGF gene into the liver of rats by direct electroporation as a means to prevent radiation-induced liver damage. METHODS: Rat whole liver irradiation model was accomplished by intra-operative approach. HGF plasmid was injected into liver and transferred by electroporation using a pulse generator. Control rats (n = 8) received electrogene therapy (EGT) vehicle plasmid and another 8 rats received HGF-EGT 100 mug 48 h before WLIR. Expression of HGF in liver was examined by RT-PCR and ELISA methods. Apoptosis was determined by TUNEL assay. Histopathology was evaluated 10 wk after whole liver irradiation. RESULTS: Marked decrease of apoptotic cells and down-regulation of transforming growth factor-beta 1 (TGF-beta1) mRNA were observed in the HGF-EGT group 2 d after liver irradiation compared to control animals. Less evidence of radiation-induced liver damage was observed morphologically in liver specimen 10 wk after liver irradiation and longer median survival time was observed from HGF-EGT group (14 wk) compared to control rats (5 wk). (P = 0.031). CONCLUSION: For the first time it has been demonstrated that HGF-EGT would prevent liver from radiation-induced liver damage by preventing apoptosis and down-regulation of TGF-beta1.